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.

Sam

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

 

Successful Ageing

As I am discovering, ageing is an inevitable process. However what can you do to keep as healthy as possible in order to get the most out of life?

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If you are a Masters athlete, you will know that moving into these age groups means it is advisable to change training emphasis in order to prevent injury and compete successfully. As discussed at the recent conference Royal Society of Medicine on Sports Injuries and Sports Orthopaedics, during the session on “The Ageing Athlete”, older athletes need a longer dynamic warm up with controlled mobilisation and muscle activation, together with strength and conditioning sessions to prevent injury. Moving into next age group every five years gives the opportunity to assess and modify training accordingly.

Childhood development has an impact on long term adult health. Essentially the most rapid changes and potential peaks attained during childhood and adolescence reflect optimal physical and cognitive functioning in later life. The evidence from population cohort studies was presented by Professor Diana Kuh, director of MRC Unit for Lifelong Health and Ageing, at the recent conference at the Royal Society of Medicine. Up to 66% of the decline in functional ability in ageing adults is related to childhood development. In the case of pubertal timing, Professor Kuh described that delay causes 20% reduction of volumetric trabecular bone accrual. In my 3 year longitudinal study of 87 pre and post pubertal girls, high levels of training delayed menarche and blunted attainment of peak bone mass (PBM). Conversely an optimal level of training did not delay menarche and improved bone mineral density compared to age marched sedentary controls. A similar long term effect is seen in older female athletes who have experienced amenorrhoea of more than 6 months duration. Even after retirement and resumption of menses pre-menopause, irreversible loss of bone mineral density (BMD) is seen. Professor Kuh argued for specific and personalised recommendations to individuals to support successful ageing.

From a personalised medical perspective, what about hormonal changes associated with ageing? Although in men testosterone levels decline with age, nevertheless the change is more dramatic in women at menopause where the ovaries stop producing oestrogen and progesterone. This results in increased risk after the menopause of osteoporosis, cardiovascular disease and stroke, together with other vasomotor symptoms and mood changes. With increased life expectancy comes an increasing number of women with menopausal symptoms and health issues which can negatively impact on quality of life. What about hormone replacement therapy (HRT)? HRT improves menopausal symptoms and reduces the risk of post menopausal long term health problems, provided HRT is started within ten years after the menopause. After this window of opportunity replacement oestrogen can actually accelerate cell damage. As with any medical treatment there will be those for whom HRT is contra-indicated. Otherwise the risk:benefit ratio for each individual has to be weighed up so that women can arrive at an informed decision. Regarding the risk of breast cancer, this is increased by 4 cases per 1,000 women aged 50-59 years on combined HRT. This compares to an additional 24 cases in women who have body mass index (BMI)>30 and are not on HRT. This underlines the important of lifestyle which is crucial in all areas of preventative medicine.

What type of HRT has the most favourable risk:benefit ratio? Oral preparations undergo first pass metabolism in the liver, so other routes of delivery such as transdermal may be preferred. There is also an argument that hormones with identical molecular structure are preferable to bio-similar hormones. What functional effect could a slight difference in sex steroid structure have? For example no methyl group and a side chain with hydroxyl group (C-OH) rather than a carbonyl group (C=O)? That is the difference between oestradiol and  testosterone.

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Testosterone
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Oestradiol

In the case of hormones with identical molecular structure to those produced endogenously, there are no potential unwanted side effects or immunogenic issues as the molecule is identical to that produced by the body. Although the oestradiol component in most HRT preparations in the UK has an identical molecular structure to endogenous oestradiol, there is only one licensed micronised progesterone preparation that is has an identical molecular structure. Synthetic, bio-similar progestins have additional glucocorticoid and androgenic effects compared to molecular identical progesterone which exerts a mild anti-mineralocorticoid (diuretic) effect.

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Progesterone
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Norethisterone (synthetic progestin)

With an increasing ageing population and increase in life expectancy, it is important to support successful ageing and quality of life with a personalised and specific approach.

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

Conference Royal Society of Medicine 17/1/17 “Sports Injuries and Sports Orthopaedics” Session on “The Ageing Athlete”

Optimal health: especially young athletes! Part 3 Consequences of Relative Energy Deficiency in sports Dr N. Keay, 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

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

Bio-identical hormone replacement therapy course. Marion Gluck Training Academy 27/1/17

The British Menopause Society

Royal College of Obstetricians and Gynaecologists 

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

Optimal health: especially young athletes! Part 3 Consequences of Relative Energy Deficiency in sports

In my previous blogs I have described the adverse effects of Relative Energy Deficiency in sports (RED-S) in both female and male athletes both in terms of current health and sport performance and potential long term health problems. What about young aspiring athletes? There is concern that early sport specialisation, imbalances in training not covering the full range of the components of fitness, together with reduced sleep, all combine to increase injury risk. Young athletes are particularly vulnerable to developing RED-S during a period of growth and development accompanied by a high training load.

Sufficient energy availability and diet quality, including micronutrients, is especially important in young athletes. To investigate further I undertook a three year longitudinal study involving 87 pre- and post-pubertal girls, spread across control pupils at day school together with students in vocational training in both musical theatre and ballet streams. There was a gradation in hours of physical exercise training per week ranging from controls with least, followed by musical theatre, through to ballet stream with the most.

In all girls dietary, training and menstrual history were recorded and collected every six months. At the same visit anthropometric measurements were performed by an experienced Paediatric nurse and bloods were taken for Endocrine markers of bone metabolism and leptin. Annual DEXA scans measured body composition, total body bone mineral density (BMD) and BMD at lumbar spine (including volumetric) and BMD at femoral neck.

The key findings included a correlation between hours of training and the age of menarche and subsequent frequency of periods. In turn, any menstrual dysfunction was associated with low age-matched (Z score) BMD at the lumbar spine. There were significant differences between groups for age-matched (Z score) of BMD at lumbar spine, with musical theatre students having the highest and ballet students the lowest. There were no significant differences in dietary intake between the three groups of students, yet the energy expenditure from training would be very different. In other words, if there is balance between energy availability and energy expenditure from training, resulting in concurrent normal menstrual function, then such a level of exercise has a beneficial effect on BMD accrual in young athletes, as demonstrated in musical theatre students. Conversely if there is a mismatch between energy intake and output due to high training volume, this leads to menstrual dysfunction, which in turn adversely impacts BMD accrual, as shown in the ballet students.

I was fortunate to have two sets of identical twins in my study. One girl in each twin pair in the ballet stream at vocational school had a twin at a non-dance school. So in each twin set, there would be identical genetic programming for age of menarche and accumulation of peak bone mass (PBM). However the environmental influence of training had the dominant effect, as shown by a much later age of menarche and decreased final BMD at the lumbar spine in the ballet dancing girl in each identical twin pair.

After stratification for months either side of menarche, the peak rate of change for BMD at the lumbar spine was found to be just before menarche, declining rapidly to no change by 60 months post menarche. These findings suggest that optimal PBM and hence optimal adult BMD would not be attained if menarche is delayed due to environmental factors such as low energy density diet. If young athletes such as these go on to enter professional companies, or become professional athletes then optimal, age-matched BMD may never be attained as continued low energy density diet and menstrual dysfunction associated with RED-S may persist. Associated low levels of vital hormones such as insulin like growth factor 1 (IGF-1) and sex steroids impair bone microarchitecture and mineralisation. Thus increasing risk of injury such as stress fracture and other long term health problems. The crucial importance of attaining peak potential during childhood and puberty was described at a recent conference at the Royal Society of Medicine based on life course studies. For example, delay in puberty results in 20% reduction of bone mass.

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It is concerning that RED-S continues to occur in young athletes, with potential current and long term adverse consequences for health. Young people should certainly be encouraged to exercise but with guidance to avoid any potential pitfalls where at all possible. In my next blog I will delve into the Endocrine mechanisms involved in RED-S: the aetiology and the outcomes.

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

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

Keay N. The modifiable factors affecting bone mineral accumulation in girls: the paradoxical effect of exercise on bone. Nutrition Bulletin 2000, vol 25, no 3. 219-222.

Keay N The effects of exercise training on bone mineral accumulation in adolescent girls. Journal of Bone and Mineral Research. Vol 15, suppl 1 2000.

Keay N, Frost M, Blake G, Patel R, Fogelman I. Study of the factors influencing the accumulation of bone mineral density in girls. Osteoporosis International. 2000 vol 11, suppl 1. S31.

New S, Samuel A, Lowe S, Keay N. Nutrient intake and bone health in ballet dancers and healthy age matched controls: preliminary findings from a longitudinal study on peak bone mass development in adolescent females, Proceedings of the Nutrition Society, 1998

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

Bone health and fractures in children. National Osteoporosis Society

Lifetime influences on musculoskeletal ageing and body composition. Lecture by Professor Diana Kuh, Director of MRC Unit for Lifelong Healthy Ageing, at Royal Society of Medicine, conference on Sports Injuries and sports orthopaedics. 17/1/17

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.

Health and fitness in young people

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

skijump

As discussed in my previous blog Optimal health: including female athletes! Part 1 Bones, the female athlete triad is well described since 1984. The triad comprises disordered eating, amenorrhoea and reduced bone mineral density (BMD). What was uncertain was whether this was a reversible training effect. My study of professional retired pre-menopausal female dancers demonstrated that such bone loss is irreversible, despite resumption of menses. Furthermore, low body weight, independent of amenorrhoea, causes BMD loss. A few female athletes in my subsequent longitudinal study of professional dancers in the English National Ballet company were “robust” and continued to menstruate, in spite of low body weight. However this could have involved anovulatory cycles and therefore low oestrogen. One parameter cannot be considered in isolation.

Furthermore, it has become apparent that the female athlete triad is just part of a much larger picture, known as Relative Energy Deficiency in sport (RED-S). The fundamental issue is that of energy deficiency caused by a mismatch of energy intake and energy expenditure from exercise training. Quality of diet, including micronutrients is also important.

If you are a male athlete, you may be thinking that this is all just a problem for female counterparts? No. Male athletes can also develop RED-S, especially in sports where low body weight confers a sport performance advantage, for example long-distance runners and road cyclists (especially climbers). In a fascinating lecture, Professor Jorum Sundgot-Borgen from the Department of Sport Medicine, at the Norwegian School of Sport and Exercise Science, described the occurrence in male ski jumpers.

This energy deficient state in RED-S in both female and male athletes produces a cascade, network effect on multiple systems: immune, cardiovascular, endocrine, metabolic and haematological effects. Clearly suboptimal functioning in these key areas has implications for current physical and psychological health of athletes and therefore their sport performance. The psychological element is of note as this may be both cause and effect of RED-S. After all in order to be a successful, especially in sport, a high level of motivation, bordering on obsession, is required. Although athletes with RED-S may not fall into a defined clinical disease state, they demonstrate a subclinical condition that impacts health. Performance implications include decreased training response with reduced endurance, muscle strength and glycogen storage, alongside an increased risk of injury, probably due to impaired adaptive response to training and a decrease in co-ordination and concentration. Psychological sequelae include depression and irritability.

Some features of RED-S may be lead to irreversible health issues in the future, as seen in the case of athletic hypothalamic amenorrhoea in female athletes with permanent loss of BMD. In both male and female athletes low energy density diet relative to energy expenditure with training results in low levels of insulin like growth factor 1 (IGF-1) and sex steroid hormones which impair not only sport performance but bone microarchitecture and mineralisation. Although hypothalamic suppression in females is manifest by lack of menstruation, there is no such obvious clinical sign in males, who may nevertheless also be experiencing suppression of the hypothalamic-pituitary-gonadal axis. It has been shown that oestradiol is the key sex steroid hormone in promoting bone mineralisation: for both male and female. In males testosterone is aromatised to oestradiol which in turn acts on bone. As the same mechanisms are involved in the aetiology and effects of RED-S, then the long term consequences will most likely be the same for both female and male athletes.

In my next blog I will explore the consequences of RED-S in young athletes and delve into the Endocrine mechanisms involved in the aetiology and multi-system outcomes for male and female athletes of all ages.

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

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

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.

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

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.

Margo Mountjoy, IOC Medical Commission Games Group. Relative Energy Deficiency in Sport. Aspetar Sports Medicine Journal.

Optimal health: including female athletes! Part 1 Bones

webmd_rm_photo_of_porous_bonesIt is hard to dispute that women are underrepresented in medical research and certainly there are not many studies that include female athletes. Does this matter? After all whatever your gender the same physiological and metabolic processes occur. However the Endocrine system is where there are distinct differences in sex steroid production, which in turn have different responses in multiple target cells.

Although studies on changes in exercise performance in response to various dietary interventions and training regimes are often very interesting and well described, I am left feeling slightly uneasy when the subjects are all males. The cause for my concern is that the female hypothalamus-pituitary-ovarian axis is a particularly sensitive system with complex feedback loops and interacting networks.

Menstrual disturbance is not unusual amongst women in sport/dance where low body weight is an advantage. When a ballet dancer performs pointe work, putting full body weight through the big toe is hard enough, without extra load! Some women might consider it a convenience to be spared the hassle of menstruation. At age 24, I was perfectly fine never having had a period (primary amenorrhoea), or so I thought, being no more tired than other hospital medical colleagues working full time, studying for postgraduate medical exams and also involved in exercise training.

While working as a SHO at Northwick Park Hospital, I volunteered to be included in a study at the British Olympic Medical Association. The study was of female lightweight rowers and ballet dancers to look at VO2 max, percentage body fat and bone mineral density (BMD). I had been doing Ballet intensively (and obsessively) from a very young age, together with restricted fat and carbohydrate intake. Sounds a familiar scenario? Although I looked perfectly healthy (and I did not fit into a clinical condition requiring treatment), worked and danced well, my bone density was worryingly low. So if you are a female doing weight-bearing exercise or resistance training which loads the skeleton, these activities promoting osteogenesis will be negated if you are not ovulating and producing adequate oestrogens. The female athlete triad composed of disordered eating, amenorrhoea and low BMD was originally described by Drinkwater in 1984. However, once pathological states causing amenorrhoea have been excluded, in medical terms the female athlete triad did not necessarily constitute a disease state requiring intervention, rather subset of the “normal population”.

How significant is having low BMD compared to the age-matched population during your 20s? Could this even be viewed as a reversible adaptation to training, reflected in site specific differences in BMD according to sport? After all, when female athletes retire with decreased training “stress” and more “relaxed” diet, menses often resume and therefore does BMD also improve? This was the question I sought to answer in my study on 57 premenopausal retired professional dancers. Even with return of menses, if these athletes had experienced previous amenorrhoea of more than 6 month duration, then bone loss was irrecoverable. Current low BMD was also correlated to lowest body weight (independent of amenorrhoea) during dance career and later age of menarche. There did not appear to be any protective effect of being on the oral contraceptive pill. Constructing a model of BMD using multiple regression 33.6% of total variation in z (age matched) score for BMD at lumbar spine was accounted for by duration of amenorrhea, age at menarche and lowest body weight during dance career. So “athletic” hypothalamic amenorrhea rather than being a reversible, adaptive response has long term, irreversible effects on BMD.

Apart from bone metabolism, what other systems are impacted by mismatch of energy intake and expenditure in overtly healthy athletes? Are the endocrine and metabolic systems in male athletes also affected by subtle imbalances in training energy expenditure and dietary intake? What about young athletes? In my next blog I will explore the rationale behind the original female athlete triad now being described as part of Relative Energy Deficiency in sports (RED-S). The implications for current health and sports performance, as well as long term health in both adult men and women and young 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

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.

Keay N, Bone Mineral Density in Female Dancers, abstract Clinical Science, Volume 91, no1, July 1996, 20p.

Keay N, Dancers, Periods and Osteoporosis, Dancing Times, September 1995, 1187-1189

Keay N, A study of Dancers, Periods and Osteoporosis, Dance Gazette, Issue 3, 1996, 47

Fit to Dance? Report of National inquiry into dancers’ health

Fit but fragile. National Osteoporosis Society

Your body your risk. Dance UK

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

Optimal Health: Including Male Athletes! Part 2 – REDs Dr N. Keay, British Association Sport and Exercise Medicine

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

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

Factors Impacting Bone Development

Optimal body mass index (BMI) coupled with favourable body composition of lean mass and visceral fat is associated with accrual of bone mineral density (BMD) and peak bone mass (PBM) which is vital for setting up BMD within normal ranges for adult life.

New research demonstrates that high BMI exerts a negative effect on the accumulation of BMD and bone architecture in young people. This is something of a surprise. Elevated BMI in young people is known to have a deleterious effect on cardio-metabolic health. However, to date the thinking has been that raised BMI would at least mean that weight bearing exercise would be “weighted” and hence favour accumulation of BMD. Rather it is reported that elevated BMI with increased visceral fat results in impaired bone architecture and BMD. Coupled with decreased lean mass, this means less muscle to exert force on the skeleton to promote BMD accumulation. This distorted body composition impairs attainment of PBM.screen-shot-2016-12-01-at-08-29-56

In my research, deficiency of BMD was found to be irreversible later in adult life, despite normalising body weight, shown for those at the other end of the spectrum of BMI. Those with relative energy deficiency in sports (REDs), formally known as the female athlete triad, demonstrated suboptimal BMD correlated with previous duration of low weight, amenorrhea and delayed onset of menarche, many years on despite return to optimal body weight and normal menstrual status.

Adverse body composition with increased deposition of visceral fat is seen in patients with growth hormone (GH) deficiency, for example post pituitary surgery. Interestingly in these young people with high levels of visceral fat, low levels of GH were recorded. The proposed mechanism of suppression of GH secretion in overweight young people has been discussed. Interestingly high levels of leptin are found in overweight youngsters, compared to low levels found my studies of low weight young dancers with menstrual disturbance. In other words, there appears to be feedback between body weight, body composition and the endocrine system. The other disadvantage of high levels of adipose tissue is that fat soluble vitamin D is “fat locked” and unable to support bone mineral accumulation.

Optimal BMI and body composition are factors associated with accrual of BMD and PBM which is vital for setting up BMD within normal ranges for adult life. In those young people with high BMI and disrupted body composition, dietary measures are needed to reduce body weight. Combined with exercise, including resistance and cardiovascular weight bearing forms, to improve body composition and thus bone architecture and BMD accrual.

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

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

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

Science Daily

EurekaAlert

Paediatric Reports

Optimising Health, Fitness and Sports Performance for young people

Version 2Young people need information in order to make life decisions on their health, fitness and sport training with the support of their families, teachers and coaches.

As discussed in my previous blog anima sana in corpore sano, exercise has a positive effect on all aspects of health: physical, mental and social. The beneficial impact of exercise is particularly important during adolescence where bodies and minds are changing. This time period presents a window of opportunity for young people to optimise health and fitness, both in the short term and long term.

The physical benefits of exercise for young people include development of peak bone mass, body composition and enhanced cardio-metabolic health. Exercise in young people has also been shown to support cognitive ability and psychological wellbeing.

Optimising health and all aspects of fitness in young athletes is especially important in order to train and compete successfully. During this phase of growth and development, any imbalances in training, combined with changes in proportions and unfused growth plates can render young athletes more susceptible to overuse injuries. A training strategy for injury prevention in this age group includes development of neuromuscular skills when neuroplasticity is available. Pilates is an excellent form of exercise to support sport performance.

In athletes where low body weight is an advantage for aesthetic reasons or where this confers a competitive advantage, this can lead to relative energy deficiency in sport (RED-S). Previously known as the female athlete triad, this was renamed as male athletes can also be effected. The consequences of this relative energy deficiency state are negative effects on metabolic rate, menstrual function, bone health, protein synthesis and immunity. If this situation arises in young athletes, then this is of concern for current health and may have consequences for health moving into adulthood.

A well informed young person can make decisions to optimise health, fitness and sports performance.

Link to Workshops

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

Optimal Health: Especially Young Athletes! Part 3 – Consequences of Relative Energy Deficiency in Sports Dr N. Keay, British Association Sport and Exercise Medicine 13/4/17

Report from Chief Medical Officer

Cognitive benefits of exercise

Injuries in young athletes

Young people: neuromuscular skills for sports performance

IOC consensus statement\

Exercise and fitness in young people – what factors contribute to long term health? Dr N. Keay, British Journal of Sports Medicine