How to Identify Male Cyclists at Risk of RED-S?

Relative energy deficiency in sport (RED-S) is a clinical model that describes the potential adverse health and performance consequences of low energy availability (LEA) in male and female athletes. Identification of athletes at risk of LEA can potentially prevent these adverse clinical outcomes.

Athletes at risk of RED-S are those involved in sports where low body weight confers a performance or aesthetic advantage. In the case of competitive road cycling, being light  weight results in favourable power to weight ratio to overcome gravity when cycling uphill. How can male cyclists at risk of LEA be effectively identified in a practical manner?

Energy availability (EA) is defined as the residual energy available from dietary intake, once energy expenditure from exercise training has been subtracted. This available energy is expressed as KCal/Kg fat free mass (FFM). A value of 45 KCal/Kg FFM is roughly equivalent to basal metabolic rate, in other words the energy required to sustain health. In order to quantify EA, accurate measurements of energy intake and expenditure, and FFM assessed from dual X ray absorptiometry (DXA), need to be undertaken. However this is not practical or feasible to undertake all these measurements outside the research setting. Furthermore, methodology for assessing energy intake and expenditure is laborious and fraught with inaccuracies and subjectivity in the case of diet diaries for “free living athletes“. Even if a value is calculated for EA, this is only valid for the time of measurement and does not give any insights into the temporal aspect of EA. Furthermore, an absolute EA threshold has not been established, below which clinical symptoms or performance effects of RED-S occur.

Self reported questionnaires have been shown to be surrogates of low EA in female athletes. However there are no such sport specific questionnaires, or any questionnaires for male athletes. Endocrine and metabolic markers have been proposed as quantitative surrogate measures of EA and shown to be linked to the RED-S clinical outcome of stress fractures in runners. In female athletes the clinical sign of regular menstruation demonstrates a functioning H-P ovarian axis, not suppressed by LEA. What about male athletes? Although hypothalamic suppression of the reproductive axis due to LEA can result in low testosterone, high training loads, in presence of adequate EA, can lead to the same negative effect on testosterone concentration.

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Male cyclists present a further level of complexity in assessing EA status. In contrast to runners, stress fracture will not be an early clinical warning sign of impaired bone health resulting from low EA. Furthermore cyclists are already at risk of poor bone health due to the non weight bearing nature of the sport. Nevertheless, traumatic fracture from bike falls is the main type of injury in cycling, with vertebral fracture requiring the longest time off the bike. Chris Boardman, a serial Olympic medal winner in cycling, retired in his early 30s with osteoporosis. In other words, in road cycling, the combined effect of the lack of osteogenic stimulus and LEA can produce clinically significant adverse effects on bone health.

What practical clinical tools are most effective at identifying competitive male cyclists at risk of the health and performance consequences of LEA outlined in the RED-S model? This was the question our recent study addressed. The lumbar spine is a skeletal site known to be most impacted by nutrition and endocrine factors and DXA is recognised as the “gold standard” of quantifying age matched Z score for bone mineral density (BMD) in the risk stratification of RED-S. What is the clinical measure indicative of this established and clinically significant sign of RED-S on lumbar spine BMD? Would it be testosterone concentration, as suggested in the study of runners? Another blood marker? Cycle training load? Off bike exercise, as suggested in some previous studies? Clinical assessment by interview?

Using a decision tree approach, the factor most indicative of impaired age matched (Z score) lumbar spine BMD was sport specific clinical assessment of EA. This assessment took the form of a newly developed sports specific energy availability questionnaire and interview (SEAQ-I). Reinforcing the concept that the most important skill in clinical medical practice is taking a detailed history. Questionnaire alone can lead to athletes giving “correct” answers on nutrition and training load. Clinical interview gave details on the temporal aspects of EA in the context of cycle training schedule: whether riders where experiencing acute intermittent LEA, as with multiple weekly fasted rides, or chronic sustained LEA with prolonged periods of suppressed body weight. Additionally the SEAQ-I provided insights on attitudes to training and nutrition practices.

Cyclists identified as having LEA from SEAQ-I, had significantly lower lumbar spine BMD than those riders assessed as having adequate EA. Furthermore, the lowest lumbar spine BMD was found amongst LEA cyclists who had not practised any load bearing sport prior to focusing on cycling. This finding is of particular concern, as if cycling from adolescence is not integrated with weight bearing exercise and adequate nutrition when peak bone mass (PBM) is being accumulated, then this risks impaired bone health moving into adulthood.

Further extension of the decision tree analysis demonstrated that in those cyclists with adequate EA assessed from SEAQ-I, vitamin D concentration was the factor indicative of lumbar spine BMD. Vitamin D is emerging as an important consideration for athletes, for bone health, muscle strength and immune function. Furthermore synergistic interactions with other steroid hormones, such as testosterone could be significant.

What about the effects of EA on cycling performance? For athletes, athletic performance is the top priority. In competitive road cycling the “gold standard” performance measure is functional threshold power (FTP) Watts/Kg, produced over 60 minutes. In the current study, 60 minute FTP Watts/Kg had a significant relationship to training load. However cyclists in chronic LEA were under performing, in other words not able to produce the power anticipated for a given training load. These chronic LEA cyclists also had significantly lower testosterone concentration. Periodised carbohydrate intake for low intensity sessions is a strategy for increasing training stimulus. However if this acute intermittent LEA is superimposed on a background of chronic LEA, then this can be counter productive in producing beneficial training adaptations. Increasing training load improves performance, but this training is only effective if fuelling is tailored accordingly.

Male athletes can be at risk of developing the health and performance consequences of LEA as described in the RED-S clinical model. The recent study of competitive male road cyclists shows that a sport specific questionnaire, combined with clinical interview (SEAQ-I) is an effective and practical method of identifying athletes at risk of LEA. The temporal dimension of LEA was correlated to quantifiable health and performance consequences of RED-S.

References 

Low energy availability assessed by a sport-specific questionnaire and clinical interview indicative of bone health, endocrine profile and cycling performance in competitive male cyclists  Keay, Francis, Hind, BMJ Open in Sport and Exercise Medicine 2018

2018 UPDATE: Relative Energy Deficiency in Sport (RED-S) Keay, BJSM 2018

Fuelling for Cycling Performance Science4Performance

Pitfalls of Conducting and Interpreting Estimates of Energy Availability in Free-Living Athletes International Journal of Sport Nutrition and Exercise Metabolism 2018

IOC consensus statement on relative energy deficiency in sport (RED-S): 2018 update BJSM 2018

The LEAF questionnaire: a screening tool for the identification of female athletes at risk for the female athlete triad BJSM 2013

Low Energy Availability Is Difficult to Assess but Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes International Journal of Sport Nutrition and Exercise Metabolism 2018

Treating exercise-associated low testosterone and its related symptoms The Physician and Sports Medicine 2018

Male Cyclists: bones, body composition, nutrition, performance Keay, BJSM 2018

Cyclists: Make No Bones About It Keay, BJSM 2018

Male Athletes: the Bare Bones of Cyclists

Cyclists: How to Support Bone Health?

Synergistic interactions of steroid hormones Keay BJSM 2018

Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis Sports Medicine 2018

 

Healthy Hormones

Is your training in tune with your hormones and nutrition to optimise your athletic performance?

Hormones are internal chemical messengers regulating all aspects of your health and athletic performance. Discussed at recent BASEM conference “Health Hormones and Human Performance”

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Bone health can be at risk if hormone status not optimal

How? To enable your hormones to do the best job they can for your health and sport performance, you need to find a balance between what, how much and when you train, eat and sleep. In the diagram below, this represents staying on the healthy green plateau. Too much, or too little of any of these choices can lead to imbalances and tipping off the green plateau into the red, less healthy peripheries.

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Integrated periodisation of training, nutrition and recovery for optimal health and performance (Keay, BJSM 2017)

What? Imbalances between training load, nutrition and recovery can cause problems in the Endocrine system: the whole network of hormone interactions throughout your body. The bottom line is that if insufficient energy is provided through nutrition to cover both your training demands and the “housekeeping” activities within the body to keep you alive, then your body goes into energy saving mode. This situation is called relative energy deficiency in sports (RED-S) and has the potential to adversely impact one or more of the important systems in your body vital for optimal health and performance.

RED-S has evolved from the female athlete triad described in 1980s by Barbara Drinkwater in NEJM, where although female runners were consuming same dietary intake, those with higher training load were more likely to have menstrual dysfunction and low bone mineral density. Since this original description it has become obvious that the reproductive axis is just one of several hormone networks to be impacted by low energy availability and that RED-S also impacts the other half of the population: men.

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Potential Multisystem effects of RED-S (IOC statement BJSM 2014)

Why? Suboptimal levels of energy availability to support health and performance can arise unintentionally, for example with increased training loads and/or times of growth and development in young athletes. Intentionally restrictive eating patterns can also be the cause of RED-S, particularly in sports/dance where low body weight confers a performance or aesthetic advantage. It is an indisputable fact that in order cycle up a mountain you need to overcome gravity and produce high watts/kg. Equally it is pretty impossible to do pointe work, let alone 32 fouttées en tournant en pointe unless you are a lightweight dancer. However if this at the expense of disrupting your hormones, then the advantage of being low body weight will be lost.

How to know? How to know if you, a teammate or a fellow athlete is at risk of RED-S? If you are a female athlete then your hormones are in balance if you are having regular periods (this does not include withdrawal bleeds as result of being on the oral contraceptive pill). Any woman of reproductive age from 16 years to the menopause should have regular periods (unless pregnant). Regular menstruation acts as the barometer of healthy hormones in women. If this is not the case, whether you are an athlete or not, you need to get this checked out medically to exclude underlying medical conditions. Having excluded these, then you need to review the integrated periodisation of training, nutrition and recovery. In male athletes there is not such an obvious sign that your hormones are at healthy levels. However recurrent injury/illness/fatigue can be warning signs. The diagram below shows all the potential adverse effects of RED-S on performance. Be aware that you do not have to have all, or indeed be aware of any of these effects if you develop RED-S.

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Potential Performance effects of RED-S (IOC statement BJSM 2014)

So What? If you are an athlete/dancer, you may be thinking that none of this applies to you. You are feeling and performing fine. Maybe you have not yet experienced any of the detrimental effects of RED-S. However, you will never know how good an athlete you could be and whether you truly are performing to your full potential unless you put yourself in the best position in terms of your hormones to achieve this goal.

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Suboptimal performance as result of RED-S (Keay, BJSM 2017)

Key Points

• Insufficient nutrition intake (quantity and quality), whether intentional or not, results in RED-S and multiple hormonal disruptions

• RED-S has detrimental health and athletic performance consequences in both the short and the long term

• Some consequences of RED-S are irreversible for example poor bone health, unless intervention is swift

Check points

• Are you suffering with frequent injuries/fatigue/illness over last 3 months or more?

• Female athletes: if 16 years or older have your periods not started? Have you missed more than 3 consecutive periods?

If yes to any of above, seek medical advice from someone with experience Sports Endocrinology. Now! The longer you leave the situation the harder it will be to rectify. Initially underlying Endocrine conditions per se have to be ruled out. RED-S is a functional dysfunction of the Endocrine system, so a diagnosis of exclusion. Having established RED-S as the diagnosis, monitoring Endocrine markers can be very helpful as these are examples of objective metrics in monitoring energy availability and therefore response to optimising integrated periodisation of nutrition, training and recovery.

Slide1
Integrated periodisation of key training factors support healthy hormones to drive improvements in performance

What to do? Don’t ignore! Although you may think you are fine, if your hormones are not working for you, then you will never reach your full potential as an athlete/dancer. For female athletes having regular periods means your hormones are in healthy ranges and this is normal. Not starting and/or missing periods is not healthy, for any woman.

For both male and female athletes, if you are experiencing recurrent injury, fatigue or illness, you need to get this checked out. There may be a simple explanation such as viral infection, low vitamin D or iron. However it may be that the underlying reason is due to hormone issues.

If you are an athlete, coach, teacher or parent and concerned that you/an athlete in your care has not got the balance right to optimise health and athletic performance, then a 3 way discussion will help and support the decision to seek medical advice as appropriate.

References

Lifestyle Choices for optimising health: exercise, nutrition, sleep Keay, BJSM 2017

Optimal health: including female athletes! Part 1 BJSM 2017

Optimal health: including male athletes! Part 2 BJSM 2017

Optimal Health: Especially Young Athletes! Part 3 BASEM 2017

Optimal Health: For All Athletes! Part 4 BASEM 2017

Low Energy Availability is Difficult to Assess But Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes Sport Nutrition and exercise Metabolism 2017

Cumulative Endocrine Dysfunction in Relative Energy Deficiency in Sport (RED-S) BJSM 2018

Presentation at BASEM conference “Health, Hormones and Human Performance”

 

Male Athletes: the Bare Bones of Cyclists

Chris Boardman is an Olympic gold medal winner and world record breaking cyclist. However, he explains in his biography that he retired in his early thirties with weak bones and low testosterone. At the time he was treated with medication aimed at improving his bone strength, but this severely impacted his performance on the bike.

What was the cause of this superlative male athlete’s unhealthy condition that ultimately lead to his retirement? Is this still an issue for male cyclists today? Is it limited to elite professional riders?

Slide1
Periodisation of key training factors support the Endocrine system to optimise performance

In 2014 the IOC published a description of relative energy deficiency in sports (RED-S), where nutrition intake is insufficient to cover training demands and the basic “housekeeping” activities of the body. This induces an energy-saving mode that impacts health and therefore athletic performance. The female athlete triad had been previously described as the combination of disordered eating, menstrual disruption and impaired bone health. RED-S goes beyond the female athlete triad to include a broader range of  impacts on systems other than just the bones and female hormone production. Significantly RED-S includes male athletes. Today, Chris Boardman would be diagnosed with RED-S.

Has this new information improved the identification and support of male athletes at risk of RED-S? In a recent pilot study, 5 out of 10 competitive amateur riders (Category 2 and above) were in the lowest age-matched percentile of body fat and 9 out 10 where in the lowest 6% relative to the population of similar age. Significantly, 7 out of 10 riders had below-average for age bone mineral density (BMD) in the lumbar spine, with two males having bone densities that would be low for an 85 year old.

Why is poor bone health a particular risk for competitive male cyclists? Depending on the type of exercise, beneficial adaptations include mechanical strengthening of specific parts of the skeletal system. For example, assuming good nutrition, runners tend to have strong hips, whereas rowers have more robust spines in terms of BMD and bone microarchitecture. Conversely the non-weight-bearing nature of cycling and the generally lower level of upper-body musculature reduce the mechanical loading forces though the spine: low osteogenic (bone building) stimuli. Although similar to swimming, in the sense that body weight is supported in the water, the major difference between these two forms of exercise is that in cycling, particularly for climbing, low body mass confers a performance advantage. This brings in the additional factor for bone health of potential inadequacies in nutrition and therefore consequences on hormone production.

An optimal balance of training, nutrition and recovery drives beneficial adaptations to exercise throughout the body. The body’s Endocrine system releases hormones that stimulate positive changes, such as the process of improving the efficiency of delivering and utilising oxygen and nutrients to exercising tissues, including the skeletal system. Any imbalances in periodisation between the three inputs of training, nutrition and recovery will compromise health and athletic performance.

Cyclists are at particular risk of insufficient fuelling. This may be an intentional attempt to maintain low body weight, which can lead to healthy eating becoming an unhealthy orthorexic pattern, where vital food groups for endurance sport, such as carbohydrates are excluded. There is also a practical element to fuelling adequately during long rides and refuelling afterwards. Consistency of nutrition throughout the day has been highlighted in a recent study of male endurance athletes where although an average 24 hour intake may be sufficient, if there are any significant deficits during this time, then this is reflected in increased adverse impact on catabolic Endocrine makers. In another study of male athletes if refuelling with carbohydrate and protein after training did not occur promptly, this lead to an increase in bone resorption over formation markers.

Recovery is an essential part of a training schedule, because the adaptations to exercise occur during rest. Sleep, in particular, is a major stimulus for growth hormone release, which drives positive adaptive changes in terms of body composition and bone turnover. Conversely, insufficient recovery time due to a packed schedule of training and work, places extra stresses on the Endocrine system. Getting to bed half an hour earlier than usual every day quickly adds up to an extra night’s sleep.

Does it matter if some areas of the skeleton are weaker than others? Yes, because this increases your risk of fracture, not just if you come off your bike, but also with relatively low force impacts. In the case of runners and triathletes, bone stress injuries are more likely to occur as an early warning sign of impaired bone health due to RED-S. Since low impact forces are absent in cycling, it may take a crash to reveal the strength of a rider’s bones. Studying the list of injuries in elite cyclists there are many fractures, with longer recovery time for vertebral fractures. So potentially cyclists can develop more severe bone health issues than other athletes, before becoming aware of the situation.

If you are a male cyclist, what can you do to prevent issues of bone health and risk of developing RED-S and suboptimal performance on the bike? Watch this space! A study is planned to investigate practical and effective strategies to optimise health and performance on the bike. In meantime there will be more discussion on “Health, Hormones and Human Performance” at the BASEM conference 22 March. All welcome, including athletes and coaches, alongside healthcare professional working with athletes.

References

Mechanisms for optimal health…for all athletes! BJSM 2017

Optimal health: including female athletes! Part 1 Bones BJSM 2017

Optimal health: including male athletes! Part 2 Relative Energy Deficiency in sports BJSM 2017

Lifestyle Choices for optimising health: exercise, nutrition, sleep BJSM 2017

Sports Endocrinology – what does it have to do with performance? BJSM 2017

Relative Energy Deficiency in Sports (RED-S) Practical considerations for endurance athletes

Within-day Energy Deficiency and Metabolic Perturbation in Male Endurance Athletes International Journal of Sport Nutrition and Exercise Metabolism 2018

The Effect of Postexercise Carbohydrate and Protein Ingestion on Bone Metabolism Translational Journal of the American College of Sports Medicine 2017

Sleep for health and sports performance BJSM 2017

 

 

 

Male Cyclists: Bones, Body composition, Nutrition, Performance

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There has been much recent coverage regarding female runners suffering with health and performance issues due to relative energy deficiency in sports (RED-S). What about male athletes? A recent article about male cyclists who explained how they developed RED-S, did not receive as sympathetic a response as articles concerning female athletes. Yet multiple Endocrine network disruption in RED-S, associated with suboptimal health and performance, is equally applicable to male and female athletes.

Although competitive road cycling is excellent for cardiovascular (CV) fitness, why are male cyclists at particular risk of impaired bone health and RED-S? Cycling is a non-weight bearing type of exercise, as is swimming, so does not provide much osteogenic (bone building) stimulus. The additional element in road cycling is that, in the short term, low body weight, with associated low body fat, confers a performance advantage. However this can lead to restrictive nutrition and RED-S, that have adverse effects on health and performance, over the longer term.

A recent study looking at bone acquisition in adolescent males found that bone mass, microarchitecture and makers of bone formation were more favourable in footballers compared with cyclists and swimmers. Swimmers had the lowest Vitamin D, presumably as this is generally an indoor sport (unless you live in Australia where outdoor 50m pools abound). Another study found reduction in femoral neck bone mineral accumulation in adolescent male cyclists compared against increases over the same time frame seen in controls.

What about adult male road cyclists? When runners and cyclists were matched for age and body weight, there were no significant differences in hormone or nutrition status, yet cyclists were 7 times more likely to have osteopenia of the lumbar spine than runners. Similar results were found in another study where competitive male road cyclists were found to have reduced lumbar spine bone mineral density (BMD) for age, despite normal levels of testosterone and insulin-like growth factor 1 (IGF1), although intriguingly an inverse correlation with lumbar spine BMD and IGF1 was found. It appears that the biomechanical stress patterns on the spine in cycling are not oesteogenic in nature, which contrasts with rowing where, although also seated, the biomechanical load exerted through the spine does provide an osteogenic effect.

In addition to the non-load bearing nature of cycling on the skeleton, restrictive nutrition can contribute to suboptimal bone health. Reducing energy availability by restricting energy intake whilst increasing training load can be a strategy, especially during pre-season training to reduce body weight and body fat. Essentially, cycling up a steep incline demands less power through the pedals if your body weight is low. Nevertheless, reducing energy availability runs the risk of developing RED-S, associated Endocrine dysfunction and suboptimal bone health, on top of the non-beneficial mechanical osteogenic effect of cycling. On a practical note, with long training rides in the saddle it can be physically and practically difficult to fuel optimally. Recent research in female athletes shows that within day energy deficits magnify hormonal disruption. Could this be a factor in male cyclists where consistent fuelling is either actively avoided and/or practically difficult?

The psychological element of disordered eating has been described amongst elite male cyclists. Male cyclists, in particular, collect many metrics associated with training and racing which could be a manifestation of a drive to perfectionism. Determination and attention to detail are laudable qualities for athletes, but there is a fine line when the balance swings to behaviours and attitudes that can be detrimental to health and performance. Even starting off with good intentions can lead to problems as seen with the growing emergence of orthorexia: “clean eating”, which, ironically, becomes detrimental to health and performance with exclusion of food groups such as carbohydrates.

Exclusively practising a non weight bearing sport such as cycling although great for CV fitness, is not so good for bone health. Does this matter? Potentially injury is more likely in bike spills, which occur both in training and competition even for the most experienced bike handler. Combined with the drive for low body weight in competitive road cycling, health and performance issues can be compounded with RED-S. What are the solutions for the cyclist to support favourable body composition and bone health, which ultimately also optimises performance? A further planned study, following a current pilot study of competitive road cyclists, aims to investigate the potential beneficial effects of strength and conditioning to load the skeleton combined with a review of nutrition. See details of next study to see if you wish to participate.

For more discussion on the Endocrine aspects of Sports and Exercise Science and Medicine, BASEM Spring conference 22 March 

References

Cumulative Endocrine Dysfunction in Relative Energy Deficiency in Sport (RED-S)

Optimal health: including male athletes! Part 2 Relative Energy Deficiency in sports BJSM 2017

Too healthy to ride? How clean living could slow you down Cycling Weekly 2017

Body Composition for Health and Sports Performance

Longitudinal Adaptations of Bone Mass, Geometry, and Metabolism in Adolescent Male Athletes: The PRO-BONE Study JBMR 2017

Bone Related Health Status in Adolescent Cyclists Plos 2011

Participation in road cycling vs running is associated with lower bone mineral density in men Metabolism 2008

Evaluation of the Bone Status in High-Level Cyclists Journal of Clinical Densitometry 2012

Effect of exercise training programme on bone mineral density in novice college rowers BJSM 1995

Energy Intake and Energy Expenditure of Elite Cyclists During Preseason Training Int J Sports Med 2005
Kings and Queens of the Mountains Science4Performance 2017

Cumulative Endocrine Dysfunction in Relative Energy Deficiency in Sport (RED-S)

Perfectionism and Risk for Disordered Eating among Young French Male Cyclists of High Performance Perceptual and Motor Skills 2004

Kings and Queens of the Mountains Science4Performance 2017

Addiction to Exercise – what distinguishes a healthy level of commitment from exercise addiction? BJSM 2017

Optimal Health: For All Athletes! Part 4 – Mechanisms BASEM 2017

 

 

 

 

 

Cumulative Endocrine Dysfunction in Relative Energy Deficiency in Sport (RED-S)

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Unfortunately I continue to see athletes, both male and female, whose health and athletic performance is hampered due to Relative Energy Deficiency in Sports (RED-S). There have been some high profile athletes who have been very open about how RED-S has affected them, alerting younger athletes to potential pitfalls.

Does this issue warrant highlighting? Yes! The athletes I see and those that speak out are only just the tip of the iceberg. In a study of exercising females, half were found to have subtle menstrual hormone disruption such as luteal phase deficit or anovulation. A third were amenorrhoeic, with no periods at all. All women of reproductive age, whether an athlete or not, should have regular periods, otherwise there are potential serious health and performance sequaelae. However studies in both the USA and Australia have revealed that the majority of young exercising women are not aware of the link between menstrual disruption and deleterious, potentially irreversible effects on bone health.

The impact of non-integrated periodisation of training, nutrition and recovery has evolved since the early description of the female athlete triad. The constellation of amenorrhoea, disordered eating and osteoporosis is now considered to be a clinical spectrum. In turn the female athlete triad is part of a much broader picture of RED-S, which includes adverse multi-system effects beyond bone health and is also seen in male athletes.

Although an athlete may appear healthy, what are the underlying Endocrine disruptions occurring in RED-S that ultimately will impede both optimal health and performance to full potential? In general, female exercisers are more susceptible to internal and external perturbations as the female Endocrine system is more finely balanced than in males. Nevertheless, in a study of male athletes, in the short time period after completing a training session, bone turnover was adversely affected, with an increase in markers of resorption relative to formation, if an athlete did not refuel rapidly with protein and carbohydrate. In the now classic research by Loucks, 5 days of manipulated energy restricted availability, via dietary intake and exercise output, caused disruption in LH pulsatility in previously eumenorrhoeic women. From this research and subsequent studies, not only is the reproductive axis disrupted with reduced energy availability, in addition hypothalamus-pituitary-thyroid (decreased T3) and adrenal axes (increased cortisol) and decreased IGF1 due to relative GH resistance are all disrupted. These interactive hormonal dysfunctions occur even before reduction in sex steroids. A recent study demonstrated that beyond the average energy availability over a 24 hour time window, within day energy deficits in terms of duration and magnitude are associated with a greater degree of disruption of Endocrine and metabolic markers, in particular decreased oestradiol and increased cortisol. So consistency of nutrition, not only during a training season but from day to day is vital.

Although energy availability is the crucial factor in the pathophysiology of RED-S, measuring this is not practical for all athletes in terms of accuracy and cost. Clinical menstrual status in female athletes and basic Endocrine markers are proposed as being more reliable and accessible. The Endocrine system is very sensitive to internal and external perturbations, as described above, and presages performance consequences of RED-S, such as injury. An important starting point is for all female athletes is to ask themselves: are my periods regular? This is also a vital question that coaches and parents need to consider for athletes in their care. If the answer is no, then this needs to be assessed, ideally by those with experience in Sports Endocrinology.

Why are these clinical and biochemical markers of Endocrine dysfunction important for athletes? Essentially there are significant health and performance implications for athletes. As outlined in the stories of female athletes, by the time career limiting stress fractures become obvious, typically in early twenties, the Endocrine system has been in disarray for a significant time. Long term, irreversible poor bone health and adverse body composition have been established.

In my opinion, emphasis should be placed on the positive outcome of integrating periodised training, nutrition and recovery to support a functional Endocrine system and therefore optimal health and ability to reach full athletic potential. For example for female athletes, competing in sports where low body mass confers a performance advantage, such as ballet, gymnastics and road cycling, finely tuned neuromuscular skills are essential to reach maximal potential and minimise injury risk. Yet these are the athletes most at risk of developing RED-S, with consequential adverse effects on menstrual cycles, endogenous oestrogen secretion and neuromuscular function.

Rather than reading headlines about the concerning health issues amongst athletes, more guidance for athletes and those working with them, on the warning signs and how to combat RED-S are needed so that athletes can reach their full potential and the headlines become about athlete achievements.

For more discussion on the Endocrine and Metabolic aspects of Sport and Exercise Medicine, all members of multi-disciplinary team working with athletes, including athletes and coaches are welcome to the BASEM Spring Conference

BAsem2018_SpringConf_BJSM

References

Relative Energy Deficiency in Sports (RED-S) Practical considerations for endurance athletes

British middle-distance runner Bobby Clay is struggling with osteoporosis but wants her experience to act as a lesson for fellow young athletes Athletics Weekly 2017

In a special AW report, former English Schools champion Jen Walsh reveals the devastation that the female athlete triad can wreak Athletics Weekly 2017

Optimal Health: Especially Young Athletes! Part 3 – Consequences of Relative Energy Deficiency in Sports BASEM 2017

Prevalence High prevalence of subtle and severe menstrual disturbances in exercising women: confirmation using daily hormone measures. Human Repro 2010

Energy deficiency, menstrual disturbances, and low bone mass: what do exercising Australian women know about the female athlete triad? Int J Sport Nutr Exerc Metab. 2012

Female adolescent athletes’ awareness of the connection between menstrual status and bone health J Pediatr Adolesc Gynecol. 2011

Optimal health: including female athletes! Part 1 Bones BJSM 2017

Optimal Health: For All Athletes! Part 4 – Mechanisms BASEM 2017

Optimal health: including male athletes! Part 2 Relative Energy Deficiency in sports BJSM 2017

Sports Endocrinology – what does it have to do with performance? BJSM 2017

The Effect of Postexercise Carbohydrate and Protein Ingestion on Bone Metabolism Translational Journal of the American College of Sports Medicine 2017

Luteinizing hormone pulsatility is disrupted at a threshold of energy availability in regularly menstruating women JCEM 2003

Within-day energy deficiency and reproductive function in female endurance athletes Scandinavian Journal of Science and medicine in Sports 2017

Low Energy Availability is Difficult to Assess But Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes Sports Nutrition and Exercise Metabolism 2017

Body Composition for Health and Sports Performance

Reduced Neuromuscular Performance in Amenorrheic Elite Endurance Athletes Medicine & Science in Sports & Exercise 2017

Relative Energy Deficiency in Sports (RED-S) Practical considerations for endurance athletes

EnergyBalance

Introduction Relative Energy Deficiency in Sport (RED-S) has evolved from the previously described Female Athlete Triad (menstrual dysfunction, disordered eating and decreased bone mineral density). The reason for the development of this clinical model of RED-S is that it has become apparent that low energy availability, ie not eating enough calories to support the combined energy demands of health and training, has more widespread adverse impacts on health and consequently performance in athletes and dancers than previously recognised. Furthermore, the RED-S model includes both male and female athletes– so if you are a male athlete, please do not stop reading! Low energy availability can impact male and female exercises of all levels and of all ages. Young developing athletes can be at particular risk of RED-S as this represents a time of growth and development, which entails many nutritional demands, in addition to those to support training. This represents a time to set up the template for health into adulthood.

Why does RED-S occur? RED-S is particularly prevalent in sports where low body weight confers a performance advantage or for aesthetic reasons. For example: long distance running, triathlon, gymnastics, dance and cycle road racing. However, RED-S could also occur not as an intentional strategy to control body weight, but rather during cycles of increased training load where periodised nutrition has not been synchronised with the increased demand on the body.

What is RED-S? Fundamentally there is a mismatch between food intake (in terms of energy and micronutrients) and the demand for nutrition required to cover expenditure, both of exercise training and for basic “housekeeping” tasks in the body to maintain health. If there is insufficient energy availability, then the body switches into an energy saving mode. This “go slow” mode has implications for hormone production and metabolic processes, which impacts all systems throughout the body. The reason why RED-S was originally described as the Female Athlete Triad is that in women the “energy saving mode” involves menstrual periods being switched off: a pretty obvious external sign as all women of child bearing age should have periods (apart from when pregnant). Low oestrogen levels have an adverse effect on bone health, resulting in decrease in bone mineral density. This effectively renders young women at increased risk of both soft tissue and bone injury, as seen in post-menopausal women. As described in the IOC statement published 2014 and updated 2018 in British Journal of Sports Medicine , the Female Athlete Triad is now recognised as just the tip of the iceberg. Disruption of hormone levels does not only adversely impact menstrual periods and bone health. There are knock on effects impacting the immune system, cardiovascular system, muscles, nervous system, gut health and the list goes on. Importantly, it is recognised that this situation is also seen in male athletes: low energy availability resulting in adverse health and performance consequences. Although exercise/dance is known to have many beneficial effects on health, all these beneficial effects are negated by low energy availability. For example, whether or not a sport is weight bearing, which traditionally improves bone health, in RED-S the predominant effect of disrupted hormones is to decrease bone density, leading to increased fracture risk.

Male cyclists Road cyclists are doubly at risk of the detrimental effects of RED-S on bone health. Performing a non-weight bearing form of exercise deprives the skeleton of the positive effect of mechanical skeletal loading on bone health. Furthermore being low body weight is a performance advantage for road cyclists when it comes to riding up hills/mountains in order to produce higher Watts/Kg over 60 minutes (60 minute functional threshold power FTP). This puts cyclists at risk of developing low energy availability, endocrine dysfunction and consequent impairment of bone health. In weight bearing sport the warning sign of suboptimal bone health if often stress fracture. This will be absent in cyclists. Hence low energy availability may go unrecognised until a bike fall results in serious fracture and indeed fractures appears as the most common type of injury amongst cyclists. Furthermore, the lumbar spine is recognised as the site most susceptible to endocrine dysfunction in RED-S. Vertebral fracture is recorded as the type of fracture in cyclists requiring the longest time off the bike. In a recent study, it was found that the factor most indicative of 60 minute FTP, was training load and NOT low body fat. Furthermore, training in low energy availability state will not result in the expected 60 minute FTP performance. So far more effective to train with sufficient nutrition on board, rather than restricting intake which will render training less effective.

What is the significance of RED-S? Do these effects of RED-S matter? Yes: there is a detrimental effect on not only health, but on all elements of sports performance. These include an inability to improve as expected in response to training and increased risk of injury. In the long-term there are potential implications for health with inability to reach peak bone mass for young athletes and at the other end of the scale, irreversible bone loss being seen in retired athletes.

Here is a summary of the potential impact of RED-S:

• Endocrine dysfunction: decreased training response

• Metabolic disruption: decreased endurance performance

• Bone health: increased risk bone stress injuries

• Decreased functional immunity: prone to infection

• Gut malfunction: impaired absorption of nutrients

• Decreased neuromuscular co-ordination: injury risk

• Psychological impact: inability to recognise risk developing RED-S

As you can see, these adverse effects are all relevant to performance in endurance sport.

What to do if you are concerned you may have RED-S?

Health Considerations:

• Women: even if your adult weight is steady, if you are a female athlete of reproductive age whose periods have stopped, then do not ignore this! In the first instance, you need to exclude any other causes (for example polycystic ovary syndrome and other hormone issues) in conjunction with your doctor. Then take a look at how you are eating in line with your training load – see the nutritional considerations section below.

• Men: if you are a male athlete struggling to improve sport performance, then review both your training load and your periodised nutrition and recovery. If the cause is RED-S then do not wait until your sport performance drops or you get injured before taking action. You may also want to consider having your testosterone levels measured to check that these are in the normal range.

Nutritional Considerations: From colleague Jo Scott-Dalgleish BSc (Hons), mBANT, CNHC

It is important to consider whether the energy deficiency that you are experiencing is intentional or unintentional.

Intentional: you may be deliberately restricting your calorie intake to lose weight and body fat, although you are already a healthy weight, as you believe this will improve your power-to-weight ratio or run speed.

  • If you are trying to lose weight – or anxious about gaining weight – and experiencing issues with hormones (such as missing your periods or not experiencing morning erections) or bone health (such as getting a stress fracture) or finding that your performance is declining rather than improving, it may be time to seek support.
  • This is particularly important if your eating patterns have become disordered, eg exclusion of multiple food groups, binge eating and/or purging, or deliberately avoiding social situations around food.
  • Please visit the resources section of an excellent campaign website that has been put together to help athletes talk more openly about their experiences with food, disordered eating and RED-S and find help: https://trainbrave.org/resources/.
  • Another great resource to learn more about RED-S and how it can adversely affect your health is http://health4performance.co.uk/athlete-dancer/

Unintentional: eating fewer calories than your body needs when you are training hard is common in endurance athletes and often not deliberate.

  • You may not yet be experiencing the symptoms of RED-S outlined as above, but you are greatly at risk of doing so if you continue to under-eat relative to your training over a period of months or years.
  • You do not need to be losing weight to be energy deficient, as your body’s metabolism adjusts to a lower intake but compromises on other functions while your weight stays the same. For example, you may experience constipation or bloating due to slowed digestive function. Here are some tips to help you meet your energy needs.

Here are some tips to help you to better manage your energy intake if you are at unintentional risk of RED-S.

  • Track your food intake vs energy expenditure for a short period. Use My Fitness Pal or a similar app to track these daily over the course of week. On any day when you train, if you are consuming fewer than 2500 calories as a male endurance athlete and 2000 calories as a female endurance athlete after taking your energy expenditure through training into account, your intake is likely to be inadequate as these are the guidelines for the general population. Use this data to learn more about appropriate food choices and serving sizes and introduce some changes to increase your intake in line with your training load. But I do not suggest using apps like these on a long-term basis as they may encourage an unhealthy obsession with your food intake.
    • Periodise your carbohydrate intake in line with your training. Increase your intake of starches and sugars (including vegetables and fruit) on your heavier training days. A low daily carbohydrate intake might be in the range of 2-4 g/kg of body weight. This is OK for lower volume training days but should be increased to 5-8 g/kg when training for 2-3 hours or more in a single day. This would include use of sports nutrition products like bars, gels and sports drinks during training. Again, use an app like My Fitness Pal for a week to help you assess your carbohydrate intake.
  • Pay attention to your recovery nutrition. Consuming 15-25g of protein and 45-75g of carbohydrate in the hour after exercise, whether as a snack or as part of a meal will help you to each your energy intake goals, restock your glycogen stores for your next training session and protect lean muscle mass.
  • Avoid excluding foods, whole food groups or following ‘fad diets’. Unless you have a genuine allergy or a diagnosed medical condition such as coeliac disease or lactose intolerance. Or you have been advised to avoid certain foods by a dietician or other well-qualified nutrition practitioner to help manage a health condition such as Irritable Bowel Syndrome. If you are vegetarian or vegan, see my blog here [link to https://www.endurancesportsnutritionist.co.uk/blog/vegan-diets-guide-endurance-athlete/] for tips on ensuring a well-balanced approach.
  • Focus on nutrient density. Make good quality food choices to help you get enough vitamins and minerals as well as carbohydrates, protein, fat and fibre. Try to eat fresh, minimally processed foods rather than too much packaged food, including 3-5 servings of vegetables and 2-3 pieces of fresh fruit each day.

If you are experiencing relative energy deficiency, avoid following approaches like fasted training, where the training benefits are likely to be outweighed by the pitfalls of inadequate calorie intake. I also suggest avoiding low carb-high fat diets (LCHF) due to potential adverse effects on thyroid hormones, particularly T3, which may slow down metabolism and impact on performance. It can also be difficult to obtain adequate calories from these types of diets due to the near exclusion of a whole food group – which is why they may be very effective for weight loss in people who are overweight – and the lack of carbohydrate may harm performance through a loss of metabolic flexibility, ie ability to utilise carbohydrate as fuel when required for high intensity efforts.

Conferences in Sport/Dance, Exercise Science and Medicine 2018

References

Raising Awareness of RED-S in Male and Female Athletes and Dancers Dr N. Keay, British Journal of Sport Medicine 2018

2018 UPDATE: Relative Energy Deficiency in Sport (RED-S) Dr N. Keay, British Journal of Sport Medicine 2018

Low energy availability assessed by a sport-specific questionnaire and clinical interview indicative of bone health, endocrine profile and cycling performance in competitive male cyclists. Keay N, Francis G, Hind K. BMJ Open Sport & Exercise Medicine 2018

Optimal health: including female athletes! Part 1 Bones Dr N. Keay, British Journal of Sport Medicine 2017

Optimal health: including male athletes! Part 2 Relative Energy Deficiency in sports Dr N. Keay, British Journal of Sport Medicine 2017

Optimal Health: Especially Young Athletes! Part 3 – Consequences of Relative Energy Deficiency in Sports Dr N. Keay, British Association of Sport and Exercise Medicine 2017

Mechanisms for optimal health…for all athletes! Dr N. Keay, British Journal of Sport Medicine 2017

The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S) British Journal of Sports Medicine 2014

Nutritional considerations for vegetarian endurance athletes Jo Scott-Dalgleish, Endurance Sports Nutrition 2017

 

Athletic Fatigue: Part 2

A degree of athletic fatigue following a training session, as described in part 1, is required to set in motion mechanisms to drive beneficial adaptations to exercise. At what point does this process of functional over-reaching tip into non-functional over-reaching denoted by failure to improve sports performance? Or further still along the spectrum and time scale, the chronic situation of overtraining and decrease in performance? Is this a matter of time scale, or degree, or both?

Slide1
Integrated Periodisation of Training Load, Nutrition and Recovery keeps an individual on the green plateau, avoiding descent into the red zone, due to an excess or deficiency

Determining the tipping point between these fatigue situations is important for health and performance. A first step is always to exclude underlying organic disease states, be these of Endocrine, systemic inflammatory or infective aetiologies. Thereafter the crucial step is to assess whether the periodisation of training, nutrition and recovery are integrated over a training block and in the longer term over a training season.

What about the application of Endocrine markers to monitor training load? Although the recent studies described below are more applicable to research scenarios, they give some interesting insights into the interactive networks effects of the Endocrine system and the multifactorial nature of fatigue amongst individual athletes.

In the short term, during a 2 day rowing competition, increases in wakening salivary cortisol were noted followed by return towards baseline in subsequent 2 day recovery. Despite individual variability with salivary cortisol measurement, this does at least offer a noninvasive way to adjust training loads around competition time for elite athletes.

Over an 11 day stimulated training camp and recovery during the sport specific preparatory phase of the training season, blood metabolic and Endocrine markers were measured. In the case of an endurance based training camp in cyclists, a significant increase in urea (due to protein breakdown associated with high energy demand training) and decrease in insulin-like growth factor 1 (IGF1) from baseline were noted. Whereas for the strength-based athletes for ball sports, an increase in creatine kinase (CK) was seen, as a result of muscle damage. This study demonstrates how different markers of fatigue are specific to sport discipline and mode of training. Large inter-individual variability existed between the degree of change in markers and degree of fatigue.

In the longer term, for the case of overtraining syndrome potential Endocrine markers have been reviewed. Whilst basal levels of most measured hormones remained stable, a blunted submaximal exercise response of growth hormone (GH), prolactin and ACTH could be indicative of developing overtraining syndrome. Whilst this review is interesting, dynamic testing is not a practical approach and these findings are not specific to over training. Rather this blunted dynamic exercise response would indicate relative suppression of the neuroendocrine hypothalamic-pituitary axis which could potentially involve other stressors such as inadequate sleep or poor nutrition. Although basal levels may lie “within the normal range”, if both pituitary derived stimulating hormone and end endocrine gland hormone concentrations fall in the lower end of the normal ranges (eg low end of range TSH and T4) this is consistent with mild hypothalamic suppression observed over the range of training and fatigue conditions (functional/non-functional and overtraining) and/or Relative Energy Deficiency in Sports (RED-S).

Although the studies above are of research interest, non invasive monitoring, specific to an athlete is more practical for monitoring the effects of training. Several useful easily measurable metrics can give clues: resting heart rate, heart rate variability, power output. Tools on Strava and Training Peaks provide practical insights in monitoring training effectiveness via these metrics. A range of mobile apps makes it ever easier to augment a personal training log to include these training metrics, along with feel, sleep and nutrition. Such a log provides feedback on health and fitness for the individual athlete, in order to personalise training plans. Certainly adding the results from any standard basal blood tests will also help add to the picture, along the lines of building a longitudinal personal biological passport. After all, “normal ranges” are based on the general population, of which top level athletes may represent a subgroup. The more personalised the metics recorded over a long time scale, the more sensitive and useful the process to guide improvement in sport performance.

Context is key when considering athletic fatigue: temporal considerations and individual variation. Certainly the interactive network effects of the Endocrine system are important in determining the degree of adaptation to exercise and therefore sports performance. However the Endocrine system acts in conjunction with many other systems (metabolic, immune and inflammatory), in determining the effectiveness of training in improving sports performance. So it is not surprising that one metric or marker in isolation is not predictive of fatigue status in individual athletes.

For more discussion on Health, Hormones and Human Performance come to the British Association of Sport and Exercise Medicine annual conference

Presentations

References

Athletic Fatigue: Part 1

Endocrine system: balance and interplay in response to exercise training

Temporal considerations in Endocrine/Metabolic interactions Part 1

Fatigue, sport performance and hormones..more on the endocrine system Dr N Keay, British Journal of Sports Medicine 2017

Sport Performance and RED-S, insights from recent Annual Sport and Exercise Medicine and Innovations in Sport and Exercise Nutrition Conferences Dr N Keay, British Journal of Sports Medicine 2017

Capturing effort and recovery: reactive and recuperative cortisol responses to competition in well-trained rowers British Journal of Sports Medicine

Blood-Borne Markers of Fatigue in Competitive Athletes – Results from Simulated Training Camps Plos One

Hormonal aspects of overtraining syndrome: a systematic review BMC Sports Science, Medicine and Rehabilitation 2017

Clusters of Athletes – A follow on from RED-S blog series to put forward impact of RED-S on athlete underperformance Dr N Keay, British Association of Sport and Exercise Medicine 2017

Strava Fitness and Freshness Science4Performance 2017

From population based norms to personalised medicine: Health, Fitness, Sports Performance Dr N Keay, British Journal of Sports Medicine 2017

Sports Endocrinology – what does it have to do with performance? Dr N Keay, British Journal of Sports Medicine 2017

Athletic Fatigue: Part 1

Interpreting athletic fatigue is not easy. Consideration has to be given to context and time scale. What are the markers and metrics that can help identify where an athlete lies in the optimal balance between training, recovery and nutrition which support beneficial adaptations to exercise whilst avoiding the pitfalls of fatigue and maladaptation? This blog will discuss the mechanisms of athletic fatigue in the short term.

Screen Shot 2017-08-30 at 09.17.58
Proposed causes of fatigue dependent on duration and intensity of training session

In the short term, during an endurance training session or race, the temporal sequence of athletic fatigue depends on duration and intensity. It is proposed that below lactate threshold (LT1), a central mechanism governs: increasing central motor drive is required to maintain skeletal muscular power output until neuromuscular fatigue cannot be overcome. From lactate threshold (LT1) to lactate turn point (LT2), a combination of central and peripheral factors (such as glycogen depletion) are thought to underpin fatigue. During high intensity efforts, above LT2 (which correspond to efforts at critical power), accumulation of peripheral metabolites and inability to restore homeostasis predominate in causing fatigue and ultimately inability to continue, leading to “task failure”. Of course there is a continuum and interaction of the mechanisms determining this power-duration relationship. As glycogen stores deplete this impacts muscle contractility by impairing release of calcium from the sarcoplasmic reticulum in skeletal muscle. Accumulation of metabolites could stimulate inhibitory afferent feedback to central motor drive for muscle contraction, combined with decrease in blood glucose impacting central nervous system (CNS) function.

Even if you are a keen athlete, it may not be possible to perform a lactate tolerance or VO2 max test under lab conditions. However a range of metrics, such as heart rate and power output, can be readily collected using personalised monitoring devices and then analysed. These metrics are related to physiological markers. For example heart rate and power output are surrogate markers of plasma lactate concentration and thus can be used to determine training zones.

A training session needs to provoke a degree of training stress, reflected by some short term fatigue, to set in motion adaptations to exercise. At a cellular level this includes oxidative stress and exerkines released by exercising tissues, backed up by Endocrine responses that continue to take effect after completing training during recovery and sleep. Repeated bouts of exercise training, followed by adequate recovery, result in a stepwise increase in fitness. Adequate periodised nutrition to match variations in demand from training also need to be factored in to prevent the Endocrine system dysfunction seen in Relative Energy Deficiency in Sports (RED-S), which impairs Endocrine response to training and sports performance. Integrated periodisation of training/recovery/nutrition is essential to support beneficial multi-system adaptations to exercise on a day to day time scale, over successive training blocks and encompassing the whole training and competition season. Psychological aspects cannot be underestimated. At what point does motivation become obsession?

In Part 2 the causes of athletic fatigue over a longer time scale will be discussed, from training blocks to encompassing whole season.

For more discussion on Health, Hormones and Human Performance come to the British Association of Sport and Exercise Medicine annual conference

Presentations

References

Endocrine system: balance and interplay in response to exercise training

Power–duration relationship: Physiology, fatigue, and the limits of human performance European Journal of Sport Science 2016

Strava Ride Statistics Science4Performance 2017

Sleep for health and sports performance Dr N Keay, British Journal of Sports Medicine 2017

Relative Energy Deficiency in Sports (RED-S) Practical Considerations for Endurance Athletes

Sports Endocrinology – what does it have to do with performance? Dr N Keay, British Journal of Sports Medicine 2017

Optimal Health: For All Athletes! Part 4 – Mechanisms Dr N Keay, British Association of Sport and Exercise Medicine 2017

Addiction to Exercise – what distinguishes a healthy level of commitment from exercise addiction? Dr N Keay, British Journal of Sports Medicine 2017

 

 

Addiction to Exercise

ExerciseAddiction

Health is not just the absence of illness, but rather the optimisation of all components of health: physical, mental and social. Exercise has numerous benefits on all these aspects. However, a recent article in the British Medical Journal described how exercise addiction can have detrimental physical, mental and social effects.

Dedication and determination are valuable qualities required to be successful in life, including achieving sporting prowess. Yet, there is a fine line between dedication and addiction.

To improve sports performance, cumulative training load has to be increased in a quantified fashion, to produce an overload and hence the desired physiological and Endocrine adaptive responses. Integrated periodisation of training, recovery and nutrition is required to ensure effective adaptation. Sufficient energy availability and quality of nutrition are essential to support health and desired adaptations. On the graph above the solid blue line represents a situation of energy balance, where the demands of increased training load are matched by a corresponding rise in energy availability. This can be challenging in sports where low body weight confers a performance or aesthetic advantage, where the risk of developing relative energy deficiency in sport (RED-S) has implications for Endocrine dysfunction, impacting all aspects of health and sports performance.

Among those participating in high volumes of exercise, what distinguishes a healthy level of commitment from exercise addiction? Physical factors alone are insufficient: all those engaging in high levels of training can experience overuse injuries and disruption in Endocrine, metabolic and immune systems. Equally, in all these exercising individuals, overtraining can result in underperformance.

Psychological factors are the key distinguishing features between the motivated athlete and the exercise addict. In exercise addiction unhealthy motivators and emotional connection to exercise can be identified as risk factors. In exercise addiction the motivation to exercise is driven by the obsession to comply with an exercise schedule, above all else. This can result in negative effects and conflict in social interactions, as well as negative emotional manifestations, such as anxiety and irritability if unable to exercise, including the perceived necessity to exercise even if fatigued or injured.

Two categories of exercise addiction have been described. Primary exercise addiction is the compulsion to follow an excessive training schedule. Without balancing energy intake, the physical consequence may be a relative energy deficiency, as indicated on the graph by the dashed blue line. In secondary exercise addiction, the situation is compounded by a desire specifically to control body weight. These individuals consciously limit energy intake, almost inevitably developing the full clinical syndrome described in RED-S, dragging them down to the position indicated by the dotted blue line on the chart. These situations of exercise addiction can lead to varying risk categories of RED-S.

As described at the start of this blog, there is a blurred boundary between the dedicated athlete and the exercise addict. In practice there is most likely a cross over. For example, an athlete may start with healthy motivators and positive emotional connection to exercise, which can become a primary addiction to adhere rigidly to a training schedule, rather than putting the emphasis on the outcome of such training. In the case of an athlete where low body weight is an advantage, it is easy to appreciate how this could become a secondary exercise addiction, where the motivation for exercising becomes more driven by the desire to control weight, rather than performance.

In order to support those with exercise addiction, discussion needs to focus on adopting a more flexible approach to exercise, by recognising that exercise addiction has detrimental effects on all aspects of current and long term health. Furthermore, in the case of athletes, a multi-disciplinary approach is desirable to help the individual refocus on the primary objective of training: to improve performance. In all situations, discussion should explore modifications to exercise and nutrition, in order to prevent the negative effects of RED-S on health and performance.

Exercise has numerous health benefits and is usually viewed as positive behaviour. However, the outcome of exercise is related to the amount of training, appropriate nutrition and motivation for exercising.

For further discussion on Endocrine and Metabolic aspects of SEM come to the BASEM annual conference 22/3/18: Health, Hormones and Human Performance

References

Addiction to Exercise British Medical Journal 2017

Clusters of Athletes British Association of Sport and Exercise Medicine 2017

Sport performance and relative energy deficiency in sport British Journal of Sport Medicine 2017

Balance of recovery and adaptation for sports performance British Association of Sport and Exercise Medicine 2017

Optimal Health for all athletes Part 4 Mechanisms of RED-S British Journal of Sport Medicine 2017

Sports Endocrinology – what does it have to do with performance? British Journal of Sport Medicine 2017

Inflammation: Why and How Much? British Association of Sport and Exercise Medicine 2017

Clusters of Athletes

 At some time, most athletes experience periods of underperformance. What are the potential causes and contributing factors?

classification

Effective training improves sports performance through a process of adaptation that occurs, at both the cellular and system levels, during the recovery phase. Training overload must be balanced with sufficient subsequent recovery. A long-term improvement in form is expected, following a temporary dip in performance, due to short-term fatigue.

However, when an athlete experiences a stagnation of performance, what are the potential underlying causes? How should these be addressed to prevent an acute situation developing into a more chronic spiral of decreasing performance?

Depending on clinical presentation, the first step is to exclude medical conditions. Potential infective causes include Epstein Barr virus (particularly in young athletes), Lyme disease and Weil’s disease. Systemic inflammatory conditions should be considered. Endocrine and metabolic causes include pituitary, gonadal, adrenal, thyroid  dysfunction, blood sugar control,  and malabsorption.

If medical conditions are excluded, attention should turn to the athlete’s energy balance in the context of adherence to the current training plan. Potential causes of underperformance, the inability to improve in training and competition, are illustrated in the diagram above.

Athletes in the upper right quadrant fail to live up to performance expectations, in spite of maintaining a good energy balance while adhering to the prescribed training plan. However, they may represent non-functional overreaching, where overload is not balanced with sufficient recovery. In other words, the periodisation of training and recovery is not optimised. The balance between chronic training load (fitness) and acute training load (fatigue) provides a useful metric for assessing form. Heart rate variability (HRV) can be another potentially useful measure in detecting aerobic, endurance fatigue. If the training plan is not producing the expected improvements, then this plan needs revising. Don’t forget that sleep is essential to facilitate endocrine driven adaptations to exercise training.

Athletes in the lower right quadrant are of more concern. Inadequate energy balance, especially during periods of increased training load or intentional weight loss, can be a cause of underperformance, despite the athlete being able to adhere to the training plan. This would correspond to being at risk of developing relative energy deficiency in sport (RED-S) on the amber warning in the risk stratification laid out by the International Olympic Committee.

Both of these groups are able to adhere to a training plan, but suboptimal training and recovery periodisation and/or insufficient energy intake can produce a situation of underperformance. Intervention is required to prevent them moving into the clusters on the left, representing a more chronic underperformance scenarios that are therefore more difficult to rectify.

Athletes in the upper left quadrant exhibit overtraining syndrome: a prolonged maladaptation process accompanied by a decrease in performance (not merely stagnation) and inability to adhere to training plan. The metric of decreased HRV and inability of heart rate to accelerate in response to exercise have been suggested as markers of overtraining.

Those athletes in the lower left quadrant fall into the RED-S category, where multiple interacting Endocrine networks are impacted by an energy deficient state. RED-S not only impairs sports performance, but impacts both current and future health. For example low endogenous levels of sex steroids and insulin-like growth factor 1 (IGF1) disrupt formation of bone microarchitecture and bone mineralisation, resulting in increased risk of recurrent stress fracture in addition to potentially irreversible bone loss in the longer term. In cases of recurrent injury and underperformance amongst athletes it is imperative to exclude Endocrine dysfunction and then consider whether RED-S is the fundamental cause.

There are many potential causes of underperformance in athletes. Once medical conditions have been excluded, the main aim should be to prevent acute situations becoming chronic and therefore more difficult to resolve.

For further discussion on Endocrine and Metabolic aspects of SEM come to the BASEM annual conference 22/3/18: Health, Hormones and Human Performance

References

Sport Endocrinology Dr N. Keay, British Journal of Sport Medicine 2017

Sport Performance and RED-S, insights from recent Annual Sport and Exercise Medicine and Innovations in Sport and Exercise Nutrition Conferences Dr N.Keay, British Journal of Sport Medicine 2017

Relative Energy Deficiency in Sport CPD module for British Association of Sport and Exercise Medicine

Optimal Health: For All Athletes! Part 4 – Mechanisms, Dr N. Keay, British Association of Sport and Exercise Medicine

Balance of recovery and adaptation for sports performance Dr N. Keay, British Association of Sport and Exercise Medicine

Sleep for health and sports performance Dr N. Keay, British Journal of Sport Medicine

Optimal health: including female athletes! Part 1 Bones Dr N.Keay, British Journal of Sport Medicine

Inflammation: why and how much? Dr N. Keay, British Association of Sport and Exercise Medicine

Fatigue, Sport Performance and Hormones… Dr N.Keay, British Journal of Sport Medicine

Part 3: Training Stress Balance—So What? Joe Friel

Heart Rate Variability (HRV) Science for Sport

Relative Energy Deficiency in sport (REDs) Lecture by Professor Jorum Sundgot-Borgen, IOC working group on female athlete triad and IOC working group on body composition, health and performance. BAEM Spring Conference 2015.

Prevention, Diagnosis, and Treatment of the Overtraining Syndrome: Joint Consensus Statement of the European College of Sport Science and the American College of
Sports Medicine. Joint Consensus Statement. Medicine & Science in Sports & Exercise 2012