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

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Performance Implications of RED-S (IOC statement 2014)

Introduction Relative Energy Deficiency in Sport (RED-S) has developed out of the concept of the Female Athlete Triad (menstrual dysfunction, disordered eating and decreased bone mineral density) as it has become apparent that low energy availability, ie not eating enough calories to support training levels, has more widespread adverse impacts on health consequently performance in athletes than previously recognised. RED-S can impact both male and female athletes of all ages – if you are a male athlete, please do not stop reading! 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 for training and for basic “housekeeping” tasks in the body. 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 in British Journal of Sports Medicine on RED-S, 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, this situation is also seen in male athletes: 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.

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

• Ensure an adequate energy intake. Use My Fitness Pal or a similar app to track your food intake 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, your intake is likely to be inadequate as these are the guidelines for the general population. If you are taking in fewer than 2750 calories (male) or 2250 calories (female) on a day when you are training for two hours or more, you are likely to be at increased risk of RED-S. 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.

• 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.

• 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 Jo’s blog here for tips on ensuring a well-balanced approach.

• 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. Again, use an app like My Fitness Pal for a week to help you assess your carbohydrate intake. If you are experiencing RED-S, avoid following approaches like fasted training or low carb-high fat diets (LCHF) due to potential adverse effects on hormones.

• 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.

Jo Scott-Dalgleish BSc (Hons), mBANT, CNHC, is a registered nutritional therapist specialising in nutrition for endurance sport, based in London. She works with triathletes, distance runners and cyclists to help optimise both their performance and their health through the creation of an individual nutritional plan. For more details, please visit www.endurancesportsnutritionist.co.uk.

For further discussion on Health, Hormones and Human Performance, come to the BASEM annual conference

References

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

 

Temporal considerations in Endocrine/Metabolic interactions Part 1

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It is not a simple question of what, but when we eat, sleep and exercise.

The Endocrine system displays temporal variation in release of hormones. Integrating external lifestyle factors with this internal, intrinsic temporal dimension is crucial for supporting metabolic and Endocrine health.

Amplitude and frequency of hormonal secretion display a variety of temporal patterns:

  • Diurnal variation, synchronised with external light/dark. Orchestrated by a specific area of the hypothalamus, the neuroendocrine gatekeeper.
  • Circadian rhythm, roughly 24-25 hours which can vary with season according to duration of release of melatonin from the pineal gland.
  • Infradian rhythms longer than a day, for example lunar month seen in patterns of hypothalamic-pituitary-ovarian axis hormone release during the menstrual cycle.
  • Further changes in these temporal release and feedback patterns occur over a longer timescale during the lifespan.

Hormones influence gene expression and hence protein synthesis over varying timescales outlined above. The control system for hormone release is based on interactive feedback loops. The hypothalamus is the neuroendocrine gatekeeper, which integrates external inputs and internal feedback.  The net result is to maintain intrinsic biological clocks, whilst orchestrating adaptations to internal perturbations stimulated by external factors such as sleep pattern, nutrition and exercise.

Circadian alignment refers to consistent temporal patterns of sleep, nutrition and physical activity. Circadian misalignment affects sleep-architecture and subsequently disturbs the interaction of metabolic and Endocrine health. This includes gut-peptides, glucose-insulin interaction, substrate oxidation, leptin & ghrelin concentrations and hypothalamic-pituitary-adrenal/gonadal-axes. The main stimuli for growth hormone release are sleep and exercise. Growth hormone is essential for supporting favourable body composition. These integrated patterns of environmental factors may have a more pronounced effect on those with a genetic predisposition or during crucial stages of lifespan. For example curtailed sleep during puberty can impact epigenetic factors such as telomere length and thus may predispose to metabolic disruption in later life. Regarding activity levels, there are strong relationships between time spent looking at screens and markers, such as insulin resistance, for risk of developing type 2 diabetes mellitus in children aged 9 to 10 years.

In addition to adverse metabolic effects set in motion by circadian misalignment, bone turnover has also shown to be impacted. Circadian disruption in young men resulted in uncoupling of bone turnover, with decreased formation and unchanged bone resorption as shown by monitoring bone markers. In other words a net negative effect on bone health, which was most pronounced in younger adult males compared with their older counterparts. These examples underline the importance of taking into account changes in endogenous temporal patterns during the lifespan and hence differing responses to external lifestyle changes.

For male and female athletes, integrated periodised training, nutrition and recovery has to be carefully planned over training seasons to support optimal adaptations in Endocrine and metabolic networks to improve performance. Training plans that do not balance these all these elements can result in underperformance, potentially relative energy deficiency in sport and consequences for health in both short and long term.

Part 2 will consider the longer term consequences and interactions of these temporal patterns of lifestyle factors, including seasonal training patterns in male and female athletes, on the intrinsic biochronometry controlling the Endocrine and metabolic networks during lifespan.

For further discussion on Health, Hormones and Human Performance, come to the BASEM annual conference

References

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

One road to Rome: Metabolic Syndrome, Athletes, Exercise Dr N. Keay

Metabolic and Endocrine System Networks Dr N. Keay

Endocrine system: balance and interplay in response to exercise training Dr N.Keay

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

Factors Impacting Bone Development Dr N. Keay

Sleep, circadian rhythm and body weight: parallel developments Proc Nutr Soc

Sleep Duration and Telomere Length in Children Journal of Paediatrics 2017

Screen time is associated with adiposity and insulin resistance in children Archives of Disease in Childhood

Circadian disruption may lead to bone loss in healthy men Endocrine today 2017

Successful Ageing Dr N. Keay, British Association of Sport and Exercise Medicine 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

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

Medically young, older athletes

Spot the differences?

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You don’t have to be a Radiologist to see that there are some differences between the two X-rays above. Both are from adults of the same age 51 years. Female on left as you look at screen and male on right. In both cases, these adults would be described as “medically young”. Always physically active and reasonably accomplished as athletes in their respective sport disciplines. Never smoked, never overweight, good nutrition.

As discussed at the recent conference at the Royal Society of Medicine (RSM) on “Sports Injuries and Sports Orthopaedics” in the session on the “Ageing Athlete”, there are challenges for athletes in Masters’ age groups, including mechanical joint issues associated with increasing age.

Looking at the male X-ray on right there is small gap between femoral head (ball-like structure) and acetabulum (socket in which femoral head lies). This gap is where the articular cartilage reduces friction between articulating surfaces of this ball and socket joint. In contrast in female X-ray on left of screen, this gap is reduced as cartilage has been worn away so that on right hip (left as you look at screen) bone is grinding on bone. Ouch!

Look again at the femoral heads (ball like structures). In the male these have smooth contours and are symmetrical on both sides. In contrast, in the female there is marked asymmetry with squashed appearance on right side (left of screen) of the femoral head with honeycomb appearance suggesting that there is cyst formation and impaction into socket of joint. This results in shorter leg and weakness of the bone architecture so more likely to compress further. Strangely the blood supply to femoral head is retrograde, meaning it flows backwards from origin of supplying blood vessel to provide vital nutrients to bone, which is a living tissue. If this blood supply is disrupted then the bone dies (avascular necrosis) and become more fragile. The femoral neck (slim area below femoral head) where blood supply courses, has been telescoped down and looks stubby compared to opposite side in female.

Although in the female, the right hip aches and is stiff, it is actually the left hip (right as you look at screen) that hurts more, both at rest and when trying to exercise. Why? If you look carefully on the upper boarder of acetabulum (socket) you will see small cysts. I imagine that pain is caused when the synovial fluid (lubricating fluid) in joint is forced into exposed bone, in hydraulic action especially when moving the hip joint.

So what to do? Total hip replacement (THR) is the only feasible option for the female above, due to extensive damage to the hip joints. Why are some people more prone to this type of joint damage? Apart from underlying medical pathologies that damage joints, the nature of some types of exercise can contribute. For example Ballet is demanding on the hip joint in terms of range of movement and load bearing. The individual can also be predisposed in biomechanical terms to joint issues: in the female X-ray above the femoral head is more exposed than the male.

Although the perception is that THR is more for the elderly wishing to be able to walk to the shops, with improvements in materials and technology used in hip protheses, there are examples of young athletes successfully returning to previous pre-operative levels of exercise training without pain. Recently a 28 year old male soloist dancer of the Paris Opera Ballet had a THR and returned to professional dancing. The medically young athlete will probably have the required motivation and physical ability to rehab effectively. A house in the south of France with private pool and climate for rehab outside would certainly add to motivation. Nevertheless, return to dancing at a professional level in a top level Ballet company after THR is remarkable as classical dance requires a unique combination of outstanding strength, control, proprioception and flexibility. At the conference at the RSM, during the lecture on “Can I run after my hip replacement?” hip replacements in the medically young, active population were reported to have good success rate with athletes able to return to previous level of sport with predicted lifespan of replacement of up to 25 years. Of course every individual athlete should weigh up the pros and cons. Taking up a new impact sport would probably not be sensible. Delaying surgery too long, apart from increasing pain, can compromise biomechanics and therefore replacement outcome. On the other hand, any operation carries a risk, however small and THR requires extensive rehabilitation in order to return to sport.

Deciding on the timing of THR in medically young, older athlete is not straight forward, especially if considering your own hips. Ultimately in such a person, the decision to go for surgery is based on quality of life and limitation to current sport activity, combined with the desire to return to previous level of activity, without the pain. What would you do?

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

Successful Ageing Dr N. Keay, British Association of Sport and Exercise Medicine 2017

Conference: Sports Injuries and Sports Orthopaedics, Royal Society of Medicine, 18/1/17, Session “The Ageing athlete”. Including lectures on: “Can I run after my hip replacement? Current recommendations for impact exercise following joint replacement” Mr Konan and “Managing acute injuries in worn joints” Mr Oussedik

 

 

 

Sports Endocrinology

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The Endocrine system comprises various glands distributed throughout the body that secrete hormones to circulate in the blood stream. These chemical messengers, have effects on a vast range of tissue types, organs and therefore regulate metabolic and physiological processes occurring in systems throughout the body.

The various hormones produced by the Endocrine system do not work in isolation; they have interactive network effects. The magnitude of influence of a hormone is largely determined by its circulating concentration. This in turn is regulated by feedback loops. For example, too much circulating hormone will have negative feedback effect causing the control-releasing system to down regulate, which will in turn bring the level of the circulating hormone back into range. Ovulation in the menstrual cycle is a rare example of a process induced by positive hormonal feedback.

In the control system of hormone release, there are interactions with other inputs in addition to the circulating concentration of the hormone. The hypothalamus (gland in the brain) is a key gateway in the neuro-endocrine system, coordinating inputs from many sources to regulate output of the pituitary gland, which produces the major stimulating hormones to act on the Endocrine glands throughout the body.

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The Endocrine system displays complex dynamics. There are temporal variations in secretion of hormones both in the long term during an individual’s lifetime and on shorter timescales, as seen in the diurnal variation of some hormones such as cortisol, displaying a circadian rhythm of secretion. The most fascinating and complex control system is found in the hypothalamic-pituitary-ovarian axis. Variation in both frequency and amplitude of gonadotrophin releasing factor (GnRH) secretion from the hypothalamus dictates initiation of menarche and the subsequent distinct pattern of cyclical patterns of the sex steroids, oestrogen and progesterone.

So what have the Endocrine system and hormone production got to do with athletes and sport performance?

  1. Exercise training stimulates release of certain hormones that support favourable adaptive changes. For example, exercise is a major stimulus of growth hormone, whose action positively affects body composition in terms of lean mass, bone density and reduction of visceral fat.
  2. Disruption of hormones secreted from the Endocrine system can impair sport performance and have potential long term adverse health risks for athletes. This picture is seen in the female athlete triad (disordered eating, amenorrhoea and low density) and relative energy deficiency in sport (RED-S) with multi-system effects. In this situation there is a mismatch between dietary energy intake (including diet quality) and energy expenditure through training. The net result is a shift to an energy saving mode in the Endocrine system, which impedes both improvement in sport performance and health. RED-S should certainly be considered among the potential causes of sport underperformance, suboptimal health and recurrent injury,  with appropriate medical support being provided.
  3. Caution! Athletic hypothalamic amenorrhoea, as seen in female athletes (in female athlete triad and RED-S) is a diagnosis of exclusion. Other causes of secondary amenorrhoea (cessation of periods >6 months) should be excluded such as pregnancy, polycystic ovary syndrome (PCOS), prolactinoma, ovarian failure and primary thyroid dysfunction.
  4. Unfortunately the beneficial effects of some hormones on sport performance are misused in the case of doping with growth hormone, erythropoeitin (EPO) and anabolic steroids. Excess administered exogenous hormones not only disrupt the normal control feedback loops, but have very serious health risks, which are seen in disease states of excess endogenous hormone secretion.

So the Endocrine system and the circulating hormones are key players not only in supporting health, but in determining sport performance in athletes.

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 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 17/3/17

Teaching module on RED-S for British Association of Sport and Exercise Medicine as CPD for Sports Physicians

Optimal Health: Including Female Athletes! Part 1 – Bones Dr N. Keay, British Journal of Sport Medicine 26/3/17

Optimal Health: Including Male Athletes! Part 2 – REDs Dr N. Keay, British Journal of Sport Medicine 4/4/17

Optimal health: especially young athletes! Part 3 Consequences of Relative Energy Deficiency in sports Dr N. Keay, British Association of Sport and Exercise Medicine 13/4/17

Optimal health: for all athletes! Part 4 Mechanisms Dr N. Keay, British Association of Sport and Exercise Medicine 13/4/17

Enhancing sport performance: part 1 Dr N. Keay, British Association of Sport and Exercise Medicine

Enhancing sports performance: part 3

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

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

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

Clusters of athletes Dr N. Keay, British Association of Sport and Exercise 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

Keay N, Logobardi S, Ehrnborg C, Cittadini A, Rosen T, Healy ML, Dall R, Bassett E, Pentecost C, Powrie J, Boroujerdi M, Jorgensen JOL, Sacca L. Growth hormone (GH) effects on bone and collagen turnover in healthy adults and its potential as a marker of GH abuse in sport: a double blind, placebo controlled study. Journal of Endocrinology and Metabolism. 85 (4) 1505-1512. 2000.

Wallace J, Cuneo R, Keay N, Sonksen P. Responses of markers of bone and collagen turover to exercise, growth hormone (GH) administration and GH withdrawal in trained adult males. Journal of Endocrinology and Metabolism 2000. 85 (1): 124-33.

Keay N. The effects of growth hormone misuse/abuse. Use and abuse of hormonal agents: Sport 1999. Vol 7, no 3, 11-12.

Wallace J, Cuneo R, Baxter R, Orskov H, Keay N, Sonksen P. Responses of the growth hormone (GH) and insulin-like factor axis to exercise,GH administration and GH withdrawal in trained adult males: a potential test for GH abuse in sport. Journal of Endocrinology and Metabolism 1999. 84 (10): 3591-601.

Keay N, Logobardi S, Ehrnborg C, Cittadini A, Rosen T, Healy ML, Dall R, Bassett E, Pentecost C, Powrie J, Boroujerdi M, Jorgensen JOL, Sacca L. Growth hormone (GH) effects on bone and collagen turnover in healthy adults and its potential usefulness as in the detection of GH abuse in sport: a double blind, placebo controlled study. Endocrine Society Conference 1999.

Wallace J, Cuneo R, Keay N. Bone markers and growth hormone abuse in athletes. Growth hormone and IGF Research, vol 8: 4: 348.

Keay N, Fogelman I, Blake G. Effects of dance training on development,endocrine status and bone mineral density in young girls.Current Research in Osteoporosis and bone mineral measurement 103, June 1998.

Keay N, Effects of dance training on development, endocrine status and bone mineral density in young girls, Journal of Endocrinology, November 1997, vol 155, OC15.

Keay N, Fogelman I, Blake G. Bone mineral density in professional female dancers. British Journal of Sports Medicine, vol 31 no2, 143-7, June 1997.

Keay N. Bone mineral density in professional female dancers. IOC World Congress on Sports Sciences. October 1997.

Keay N, Bone Mineral Density in Professional Female Dancers, Journal of Endocrinology, November 1996, volume 151, supplement p5.

Sport Performance and Relative Energy Deficiency in Sport

performance-potentialThe Holy Grail of any training program is to improve performance and achieve goals.

Periodisation of training is essential in order to maximise beneficial adaptations for improved performance. Physiological adaptations occur after exercise during the rest period, with repeated exercise/rest cycles leading to “super adaptation”. Adaptations occur at the system level, for example cardiovascular system, and at the cellular level in mitochondria. An increase in mitochondria biogenesis in skeletal muscle occurs in response to exercise training, as described by Dr Andrew Philip at a recent conference at the Royal Society of Medicine (RSM). This cellular level adaptation translates to improved performance with a right shift of the lactate tolerance curve.

The degree of this response is probably genetically determined, though further research would be required to establish causal links, bearing in mind the ethical considerations laid out in the recent position statement from the Australian Institute of Sport (AIS) on genetic testing in sport. Dr David Hughes, Chief Medical Officer of the AIS, explored this ethical stance at a fascinating seminar in London. Genetic testing in sport may be a potentially useful tool for supporting athletes, for example to predict risk of tendon injury or response to exercise and therefore guide training. However, genetic testing should not be used to exclude or include athletes in talent programmes. Although there are polymorphisms associated with currently successful endurance and power athletes, these do not have predictive power. There are many other aspects associated with becoming a successful athlete such as psychology. There is no place for gene doping to improve performance as this is both unethical and unsafe.

To facilitate adaptation, exercise should be combined with periodised rest and nutrition appropriate for the type of sport, as described by Dr Kevin Currell at the conference on “Innovations in sport and exercise nutrition”. Marginal gains have a cumulative effect. However, as discussed by Professor Asker Jeukendrup, performance is more than physiology. Any recommendations to improve performance should be given in context of the situation and the individual. In my opinion women are often underrepresented in studies on athletes and therefore further research is needed in order to be in a position to recommend personalised plans that take into account both gender and individual variability. As suggested by Dr Courtney Kipps at the Sport and Exercise Conference (SEM) in London, generic recommendations to amateur athletes, whether male or female, taking part in marathons could contribute to women being at risk of developing exercise associated hyponatraemia.

For innovation in sport to occur, complex problems approached with an open mind are more likely to facilitate improvement as described by Dr Scott Drawer at the RSM. Nevertheless, there tends to be a diffusion from the innovators and early adapters through to the laggards.

Along the path to attaining the Holy Grail of improved performance there are potential stumbling blocks. For example, overreaching in the short term and overtraining in the longer term can result in underperformance. The underlying issue is a mismatch between periodisation of training and recovery resulting in maladapataion. This situation is magnified in the case of athletes with relative energy deficiency in sport (RED-S). Due to a mismatch of energy intake and expenditure, any attempt at increase in training load will not produce the expected adaptations and improvement in performance. Nutritional supplements will not fix the underlying problem. Nor will treatments for recurrent injuries. As described by Dr Roger Wolman at the London SEM conference, short term bisphosphonante treatment can improve healing in selected athletes with stress fractures or bone marrow lesions.  However if the underlying cause of drop in performance or recurrent injury is RED-S, then tackling the fundamental cause is the only long term solution for both health and sport performance.

Network effects of interactions lead to sport underperformance. Amongst underperforming athletes there will be clusters of athletes displaying certain behaviours and symptoms, which will be discussed in more detail in my next blog. In the case of RED-S as the underlying cause for underperformance, the most effective way to address this multi-system issue is to raise awareness to the potential risk factors in order to support athletes in attaining their full potential.

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

Teaching module RED-S British Association Sport and Exercise Medicine

From population based norms to personalised medicine: Health, Fitness, Sports Performance Dr N. Keay, British Journal of Sport Medicine 22/2/17

Balance of recovery and adaptation for sports performance Dr N. Keay, British Association Sport and Exercise Medicine 21/1/17

Sleep for health and sports performance Dr N. Keay, British Journal of Sport Medicine 7/7/17

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

Annual Sport and Exercise Medicine Conference, London 8/3/17

Bisphosphonates in the athlete. Dr Roger Wolman, Consultant in Rheumatology and Sport and Exercise Medicine, Royal National Orthopaedic Hospital

Collapse during endurance training. Dr Courtney Kipps, Consultant in Sport and Exercise Medicine. Consultant to Institute of Sport, medical director of London and Blenheim Triathlons

Innovations in Sport and Exercise Nutrition. Royal Society of Medicine 7/3/17

Identifying the challenges: managing research and innovations programme. Dr Scott Drawer, Head of Performance, Sky Hub

Exercise and nutritional approaches to maximise mitochondrial adaptation to endurance exercise. Dr Andrew Philip, Senior Lecturer, University of Birmingham

Making technical nutrition data consumer friendly. Professor Asker Jeukendrup, Professor of Exercise Metabolism, Loughborough University

Innovation and elite athletes: what’s important to the applied sport nutritionists? Dr Kevin Currell, Director of Science and Technical Development, The English Institute of Sport

Genetic Testing and Research in Sport. Dr David Hughes, Chief Medical Officer Australian Institute of Sport. Seminar 10/3/17

Effects of adaptive responses to heat exposure on exercise performance

Over Training Syndrome, Ian Craig, Webinar Human Kinetics 8/3/17

The Fatigued Athlete BASEM Spring Conference 2014

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.

Mountjoy M, Sundgot-Borgen J, Burke L, Carter S, Constantini N, Lebrun C, Meyer N, Sherman R, Steffen K, Budgett R, Ljungqvist A. The IOC consensus statement: beyond the Female Athlete Triad-Relative Energy Deficiency in Sport (RED-S).Br J Sports Med. 2014 Apr;48(7):491-7.

Optimal health: for all athletes! Part 4 Mechanisms

As described in previous blogs, the female athlete triad (disordered eating, amenorrhoea, low bone mineral density) is part of Relative Energy Deficiency in sports (RED-S). RED-S has multi-system effects and can affect both female and male athletes together with young athletes. The fundamental issue is a mismatch of energy availability and energy expenditure through exercise training. As described in previous blogs this situation leads to a range of adverse effects on both health and sports performance. I have tried to unravel the mechanisms involved. Please note the diagram below is simplified view: I have only included selected major neuroendocrine control systems.

REDs

Low energy availability is an example of a metabolic stressor. Other sources of stress in an athlete will be training load and possibly inadequate sleep. These physiological and psychological stressors input into the neuroendocrine system via the hypothalamus. Low plasma glucose concentrations stimulates release of glucagon and suppression of the antagonist hormone insulin from the pancreas. This causes mobilisation of glycogen stores and fat deposits. Feedback of this metabolic situation to the hypothalamus, in the short term is via low blood glucose and insulin levels and in longer term via low levels of leptin from reduced fat reserves.

A critical body weight and threshold body fat percentage was proposed as a requirement for menarche and subsequent regular menstruation by Rose Frisch in 1984. To explain the mechanism behind this observation, a peptide hormone leptin is secreted by adipose tissue which acts on the hypothalamus. Leptin is one of the hormones responsible for enabling the episodic, pulsatile release of gonadotrophin releasing hormone (GnRH) which is key in the onset of puberty, menarche in girls and subsequent menstrual cycles. In my 3 year longitudinal study of 87 pre and post-pubertal girls, those in the Ballet stream had lowest body fat and leptin levels associated with delayed menarche and low bone mineral density (BMD) compared to musical theatre and control girls. Other elements of body composition also play a part as athletes tend to have higher lean mass to fat mass ratio than non-active population and energy intake of 45 KCal/Kg lean mass is thought to be required for regular menstruation.

Suppression of GnRH pulsatility, results in low secretion rates of pituitary trophic factors LH and FSH which are responsible for regulation of sex steroid production by the gonads. In the case of females this manifests as menstrual disruption with associated anovulation resulting in low levels of oestradiol. In males this suppression of the hypothamlamic-pituitary-gonadal axis results in low testosterone production. In males testosterone is aromatised to oestradiol which acts on bone to stimulate bone mineralisation. Low energy availability is an independent factor of impaired bone health due to decreased insulin like growth factor 1 (IGF-1) concentrations. Low body weight was found to be an independent predictor of BMD in my study of 57 retired pre-menopausal professional dancers. Hence low BMD is seen in both male and female athletes with RED-S. Low age matched BMD in athletes is of concern as this increases risk of stress fracture.  In long term suboptimal BMD is irrecoverable even if normal function of hypothamlamic-pituitary-gonadal function is restored, as demonstrated in my study of retired professional dancers. In young athletes RED-S could result in suboptimal peak bone mass (PBM) and associated impaired bone microstructure. Not an ideal situation if RED-S continues into adulthood.

Another consequence of metabolic, physiological and psychological stressor input to the hypothalamus is suppression of the secretion of thyroid hormones, including the tissue conversion of T4 to the more active T3. Athletes may display a variation of “non-thyroidal illness/sick euthyroid” where both TSH and T4 and T3 are in low normal range. Thyroid hormone receptors are expressed in virtually all tissues which explains the extensive effects of suboptimal levels of T4 and T3 in RED-S including on physiology and metabolism.

In contrast, a neuroendocrine control axis that is activated in RED-S is the hypothalamic-pituitary-adrenal axis. In this axis, stressors increase the amplitude of the pulsatile secretion of CRH, which in turn increases the release of ACTH and consequently cortisol secretion from the adrenal cortex. Elevated cortisol suppresses immunity and increases risk of infection. Long term cortisol elevation also impairs the other hormone axes: growth hormone, thyroid and reproductive. In other words the stress response in RED-S amplifies the suppression of key hormones both directly and indirectly via endocrine network interactions.

The original female athlete triad is part of RED-S which can involve male and female athletes of all ages. There are a range of interacting endocrine systems responsible for the multi-system effects seen in RED-S. These effects can impact on current and future health and sports performance.

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

Teaching module on RED-S for BASEM as CPD for Sports Physicians

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

Optimal health: including male athletes! Part 2 Relative Energy Deficiency in sports Dr N.Keay, British Journal of Sport Medicine 4/4/17

Optimal health: especially young athletes! Part 3 Consequences of Relative Energy Deficiency in sports Dr N. Keay, British Association of Sport and Exercise Medicine

Keay N, Fogelman I, Blake G. Effects of dance training on development,endocrine status and bone mineral density in young girls. Current Research in Osteoporosis and bone mineral measurement 103, June 1998.

Jenkins P, Taylor L, Keay N. Decreased serum leptin levels in females dancers are affected by menstrual status. Annual Meeting of the Endocrine Society. June 1998.

Keay N, Dancing through adolescence. Editorial, British Journal of Sports Medicine, vol 32 no 3 196-7, September 1998.

Keay N, Effects of dance training on development, endocrine status and bone mineral density in young girls, Journal of Endocrinology, November 1997, vol 155, OC15.

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.

Mountjoy M, Sundgot-Borgen J, Burke L, Carter S, Constantini N, Lebrun C, Meyer N, Sherman R, Steffen K, Budgett R, Ljungqvist A. The IOC consensus statement: beyond the Female Athlete Triad-Relative Energy Deficiency in Sport (RED-S).Br J Sports Med. 2014 Apr;48(7):491-7.

“Subclinical hypothydroidism in athletes”. Lecture by Dr Kristeien Boelaert at BASEM Spring Conference 2014 on the Fatigued Athlete

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