exercise

Personal Energy Availability Questionnaire (PEAQ)

12 April 2025

If you are striving to reach your peak performance, then the PEAQ can help you reach your personal full potential. Click here to get started on the PEAQ

Matching your energy intake to your energy demands helps you reach your personal peak health and exercise performance. On the other hand, failing to meet your energy demands results in low energy availability. This increases your risk of developing relative energy deficiency (REDs) and its adverse health and performance consequences.

People of any age, whatever their level and type of exercise, can be at risk of developing REDs; from elite dancers and athletes to recreational exercisers.

The PEAQ is a mobile Application that will guide you through a series of questions about exercise, physical characteristics, nutrition, hormone function and well-being. It just takes a few minutes.

Your PEAQ report instantly generates a REDs Risk Score and provides valuable insights into your energy status and potential risks, along with guidance. The PEAQ is intended for those 16 years of age and over.

The PEAQ has been developed based on in several published research studies where the questionnaire responses and scores have been correlated with measurements of hormones and bone health in athletes in various sports [1-7] and dancers [8-12]. These questionnaires were cited in the updated International Olympic Committee (IOC) consensus statement on REDs 2013.

However the PEAQ it is not a substitute for seeking medical advice. Dr Nicky Keay offers personalised health advisory appointments

Get started on your journey to reach peak performance by completing the PEAQ.

References

Keay, Francis, Hind 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 BMJ Open Sports and Exercise Medicine 2018
Keay, Francis, Hind Clinical evaluation of education relating to nutrition and skeletal loading in competitive male road cyclists at risk of relative energy deficiency in sports (RED-S): 6-month randomised controlled trial BMJ Open Sports and Exercise Medicine 2019
Keay, Francis, Hind Bone health risk assessment in a clinical setting: an evaluation of a new screening tool for active populations MOJSports Medicine 2022;5(3):84-88. doi: 10.15406/mojsm.2022.05.00125
Assessment of Relative Energy Deficiency in Sport, Malnutrition Prevalence in Female Endurance Runners by Energy Availability Questionnaire, Bioelectrical Impedance Analysis and Relationship with Ovulation status. Clinical Nutrition Open Science 2025S.
Body composition, malnutrition, and ovulation status as RED-S risk assessors in female endurance athletes, Clinical Nutrition ESPEN 2023, 58 :720-721
Keay N, Craghill E, Francis G Female Football Specific Energy Availability Questionnaire and Menstrual Cycle Hormone Monitoring. Sports Injr Med 2022; 6: 177
Keay N. Current views on relative energy deficiency in sport (REDs). Focus Issue 6: Eating disorders. Cutting Edge Psychiatry in Practice CEPiP. 2024.1.98-102
Keay N, Francis G, AusDancersOverseas Indicators and correlates of low energy availability in male and female dancers. BMJ Open in Sports and Exercise Medicine 2020
Nicolas J, Grafenuer S. Investigating pre-professional dancer health status and preventative health knowledge Front. Nutr. Sec. Sport and Exercise Nutrition. 2023 (10)
Keay N, Francis G. Longitudinal investigation of the range of adaptive responses of the female hormone network in pre- professional dancers in training March 2025 ResearchGate DOI: 10.13140/RG.2.2.30046.34880
Nicola Keay, Martin Lanfear, Gavin Francis. Clinical application of monitoring indicators of female dancer health, including application of artificial intelligence in female hormone networks. Internal Journal of Sports Medicine and Rehabilitation, 2022; 5:24.
Nicola Keay, Martin Lanfear, Gavin Francis. Clinical application of interactive monitoring of indicators of health in professional dancers J Forensic Biomech, 2022, 12 (5) No:1000380
Mountjoy M, Ackerman KE, Bailey DM et al 2023 International Olympic Committee’s (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs) British Journal of Sports Medicine 2023;57:1073-1098
Keay N “Hormones, Health and Human Potential: A guide to understanding your hormones to optimise your health and performance” Sequoia books 2022

The state of play on relative energy deficiency in sport (REDs)

2 October 2023

Long-term low energy availability leads to adaptive changes throughout the body resulting in the clinical outcomes of REDs

Earlier this week the updated consensus statement from the International Olympic Committee (IOC) on relative energy deficiency in sport (REDs) 2023 was published in the British Journal of Sport Medicine (BJSM)[1]. What are the key points from the range of papers presented in this issue dedicated to REDs?

What’s in a name change?

Making “s” lower case is helpful as relative energy deficiency is not limited to those involved in sport. You can still be at risk of REDs even if you would not consider yourself an athlete; rather “just” someone that does regular exercise. Furthermore, most genres of dance are not sport, yet dancers are another group who can be at risk.

Time scale of low energy availability

The type of adaptive responses to low energy availability is dependent on the temporal component of this energy deficient. Energy availability is the amount of energy “available” once demand from exercise has been accounted for. If this available energy is not sufficient to maintain all the “housekeeping” physiological processes, then the body will respond by going into “eco” mode and down regulating body systems[2]. A small, short-term energy deficit may not be problematic. We have all been in situations where eating patterns don’t go according to plan. For example, a particularly busy time at work, disruption to travel plans, or lack of food availability.

However, sustained, cumulative energy deficit can lead to progressive adaptation shown in the figure.

These adaptive changes across many body systems have adverse outcomes on both health and performance. This is REDs. The clinical syndrome of health and performance consequences of long-term low energy availability. This is what happened in our study of male cyclists referenced in the BJSM publication. We quantified the negative effects of low energy availability on hormone networks, bone health and performance in male cyclists[3]. Those cyclists in low energy availability lost bone mass commensurate with an astronaut in space for 6 months and underperformed in races[4]. This negative impact of low energy availability on performance was underlined in our other studies of male athletes, referenced in the IOC papers [5,6]. Ultimately these are particularly important findings for athletes and their coaches, where performance is the priority.

Menstrual cycles

This concept of a gradated adaptive response to the combined effects of training load, nutrition and recovery can be applied when considering the spectrum of reproductive axis responses in female athletes and dancers, ranging from eumenorrhoea, subclinical ovulatory disturbances to functional hypothalamic amenorrhoea[7] shown in figure of Subclinical Ovulatory Disturbance. Functional hypothalamic amenorrhoea (FHA) is potentially just the tip of the iceberg when it comes to adaptive change to low energy availability. Report of menstruation and even signs of ovulation, may belie suboptimal production of progesterone. As progesterone increases metabolic rate, low production could be considered an early response to low energy availability. This hypothesis is currently being tested in a study of dancers, funded by the British Association of Sport and exercise Medicine.

Carbohydrate availability

Although we talk about low energy availability, the updated IOC consensus statement highlights that carbohydrate availability is the key. This is based on evidence that carbohydrate is the main substrate for exercise above a certain intensity. Furthermore, the hormones of the reproductive axis are particularly sensitive to carbohydrate availability. The IOC statement highlights studies, where despite isocaloric diets, those low in carbohydrate resulted in hormone disruption and poorer athletic performance outlined in the statement.

Health is essential for performance

Another important theme is that optimal health is a prerequisite for performance. This includes both physical and mental aspects of health. Many of the psychological characteristics of athletes and dancers can predispose individuals to developing REDs. For example, although dedication, perfectionism and motivation are laudable qualities, these can spill over into behaviours around training and nutrition. This can be associated with exercise dependence and disordered eating patterns.

If an individual is anxious about body shape, weight and food, this can have a negative health outcome. For example, in our study of dancers[8], quoted as a reference in the updated IOC statement, we found that there were significant relationships between anxiety about controlling weight and eating and missing training, and physical outcomes of low BMI and physiological health in terms of lack of regular menstrual cycles. Regular menstrual cycles in women are a barometer of internal healthy hormones. Similarly in another referenced study, we found that cognitive restraint in male athletes had an adverse effect on hormone profiles[9]. How you think impacts hormone health. This interaction is shown by the reversible arrow between psychological factors as both a driver and result of REDs shown in the updated REDs health conceptual model.

Weighty matter

Weight is a measurement of gravity, not athletic potential. Being a certain weight or body composition does not guarantee athletic success. This fact was emphasised by the lead author of the special edition on REDs on the BJSM podcast. Realistically most types of exercise will involve overcoming gravity, nevertheless, there comes a tipping point where being too light weight and/or having too low body fat means being unhealthy and compromising both physical and mental performance. Furthermore, we are all individuals so our personal optimal weight and body composition will be personal to each of us. Not the generic “lighter is faster”.

Identification

Ultimately low energy availability is a concept and not measured outside of research settings. Rather, making a diagnosis of REDs is a diagnosis of exclusion. In other words, other potential medical conditions must be excluded. This can be achieved through a process of identifying those at risk with energy availability questionnaires, followed by assessing clinical symptoms and signs: such as growth trajectories in young athletes and menstrual status in female athletes and dancers. Readily available and reliable investigations such as blood tests and DXA scans are outlined. These clinical findings have been presented as primary, severe indicators (hypothalamic reproductive disruption in men and women), primary indicators, secondary indicators and other supportive factors.

When considering hormone tests is really important to emphasise that even if a result is not out of range, where the result lies in the range is crucial. Together with considering hormones as networks providing a pattern that is informative. For example, in correctly identifying subclinical down regulation of the thyroid or reproductive axis[2].

Risk stratification

Each of indicators described in the consensus statement carries a score, so that an individual can be risk stratified. The REDsCAT2 has a finer grained zone compromising of green, yellow, orange and red, replacing the 3 zoned traffic light system.

Clinical management

Ultimately as the underlying aetiology of REDs is low energy availability, then the aim of supporting an individual experiencing REDs is to restore sufficient energy availability through a combination of nutrition and possibility reducing demand from intense training. As this will involve behaviour change, this can be challenging and a multidisciplinary team approach is advised. Highlighted for female athletes experiencing functional hypothalamic amenorrhoea (FHA) and associated poor bone health, that the combined oral contraceptive pill is not advised. Rather for bone protection in the short-term HRT (transdermal oestradiol and cyclic micronised progesterone) is recommended in line with updated NICE guidelines in UK[10].

The risk of low energy availability and REDs in dancers will be dicsuused at the forthcoming British Association of Sports and Exercise Medicine annual conference 6/10/23. https://health4performance.basem.co.uk/

References

1 An update on REDs IOC consensus statement 2023 British Journal of Sports Medicine September 2023 https://bjsm.bmj.com/content/57/17?current-issue=y

2 Keay N. Hormones, Health and Human Potential Sequoia books 2023

3 Keay N, Francis G, Hind K 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. BMJ Open Sport Exerc Med 2018;4:e000424. doi:10.1136/bmjsem-2018-000424

4 Keay N, Francis G, Entwistle I et al Clinical evaluation of education relating to nutrition and skeletal loading in competitive male road cyclists at risk of relative energy deficiency in sports (RED-S): 6-month randomised controlled trial BMJ Open Sport & Exercise Medicine 2019;5:e000523. doi: 10.1136/bmjsem-2019-000523

5 Jurov I, Keay N, Spudić D et al Inducing low energy availability in trained endurance male athletes results in poorer explosive power. Eur J Appl Physiol 2022;122:503–13. doi:10.1007/s00421-021-04857-4

6 Jurov I, Keay N, Rauter S Reducing energy availability in male endurance athletes: a randomized trial with a three-step energy reduction. Journal of the International Society of Sports Nutrition 2022;19:179–95. doi:10.1080/15502783.2022.2065111

7 Keay N. Interactions of the female hormone network, exercise training and nature of adaptation. ResearchGate. June 2023 DOI: 10.13140/RG.2.2.28787.71204

8 Keay N, Overseas A, Francis G Indicators and correlates of low energy availability in male and female dancers. BMJ Open Sport ExercMed 2020;6:e000906. doi:10.1136/bmjsem-2020-000906

9 Jurov I, Keay N, Hadžić V et al Relationship between energy availability, energy conservation and cognitive restraint with performance measures in male endurance athletes. J Int Soc Sports Nutr 2021;18:24. doi:10.1186/s12970-021-00419-3

10 British Association of Sports and Exercise Medicine 2023 ‘Concerning’ lack of awareness of how best to reduce risk of stress fractures in female athletes and dancers, a year after change in NICE guidelines” https://basem.co.uk/concerning-lack-of-awareness-of-how-best-to-reduce-risk-of-stress-fractures-in-female-athletes-and-dancers-a-year-after-change-in-nice-guidelines/

Different Facets of the same Underlying Imbalances in Athlete Behaviours

11 April 2023

The Masques of Unbalanced Athlete Behaviours

Although relative energy deficiency in sport (RED-S) and overtraining syndrome (OTS) are often described as distinct entities, these can be considered as different facets of the same unbalanced behaviours. For an exerciser these behaviours consist of exercise training load, nutritional intake and recovery.

What is RED-S?

RED-S is a clinical syndrome describing adverse consequences in terms of health and performance due to sustained low energy availability (LEA). LEA is where there is a mismatch between energy intake and the combined energy demand from exercise and resting metabolic rate.

What is OTS?

OTS is a clinical syndrome describing adverse consequences in terms of health and performance when there is sustained non-functional overreaching (NFOR). NFOR is where there is an imbalance between training load relative to recovery.

It’s all about time scales

Thinking about RED-S and OTS in more detail, neither suddenly occur overnight. Rather it is the cumulative effect of energy deficit, or lack of recovery, that causes these syndromes over longer time scales of months.

Short time scales

Facets of LEA and NFOR

For example, the occasional day of suboptimal fuelling/high energy demand, with accompanying relative low energy availability, although not ideal, is nevertheless recoverable. This is shown by the warning masque of LEA of the rotating cube. On the opposite side is the warning masque of NFOR, where there have been some occasions of insufficient recovery over a short time scale of days. As with LEA, this is potentially a recoverable situation.

Longer time scales

Facets of RED-S and OTS

In practical terms, imagine you have been on a training camp or a dance intensive over a week or two. You may have unintentionally incurred a degree of LEA and NFOR, but if you take some time to rest and refuel afterwards, then you will be able to resume usual training fitter and stronger. On the other hand, if you continue to try and train at high intensity, in relative energy deficit you will progress after more weeks and months into the alert red masques of OTS and RED-S. In each case these outcomes are different facets of the same underlying imbalances in athlete/dancer behaviours around training load, nutrition and recovery.

Practical implications

When an athlete or dancer presents with symptoms that could include fatigue, poor sleep, menstrual disruption, recurrent injury (soft tissue or bone), digestive issues and other issues; it is very important to exclude medical conditions. Once this has been done and a diagnosis of exclusion made to confirm a functional issue, then deciding whether to use the terminology RED-S or OTS has a subtle nuance because in practice these syndromes are facets of the same underlying imbalance in athlete behaviours. In all cases the most important aspect is to outline a course of action for the athlete that includes training load, nutrition and recovery, in combination.

Athlete and dancer support

For example, athletes experiencing RED-S often ask if they can restore healthy hormone network function by simply eating more while maintaining a high training load. The simple answer is that this makes recovery less certain as a high training load, specifically high intensity, will most likely mean there is also a degree of NFOR. Therefore, adjustment in all athlete behaviours in synchrony is more effective for health and performance restoration. Similarly in an athlete experiencing OTS, in addition to reduction in training load, optimising nutritional intake will help.

Prevention is always better than cure

The prevention of adverse outcomes for the athlete or dancer is the other important practical implication of considering these clinical syndromes as facets of the same underlying issue. From the rotating cube of unbalanced athlete behaviours, LEA is the precursor to RED-S. Similarly, NFOR is the precursor to OTS. The progression in each case being determined by a longer time scale. Early identification of those at risk is essential to prevent this negative progression. Reversing the situation is a far easier task physiologically and psychological at an early stage of LEA and NFOR, rather than once in a “deeper hole” of RED-S or OTS.

Conclusions

RED-S and OTS being different facets of the same underlying issues of unbalanced athlete behaviours is a concept with practical implications.

References

Keay N. Hormones, Health and Human Potential. 2022 Sequoia books Act 1 Scene 9 “A Balancing Act” and Act 1 Scene 10 “In the Red”.

Excess is a Fatal Thing. Nothing Succeeds like Moderation

1 January 2023

Oscar Wilde quipped that “Moderation is a fatal thing. Nothing succeeds like excess.” However, when it comes to enjoying a healthy lifespan, nothing succeeds like moderation.

**Harnessing Hormones through Lifestyle Choices for Health**

Personalising Health through Lifestyle

Hippocrates advocated that giving each individual just the right amount of exercise and nourishment, not too little and not too much, is the safest way the health. Although Hippocrates is often known as the father of medicine, more accurately he could be described as the father of health. Health being not just the absence of disease, rather the positive combination of physical, mental and social health.

In ancient Greek times it was not known why moderation, of nutrition and exercise surely lead to health. As I describe in “Hormones, Health and Human Potential” it is the interactions of these behaviours with our hormone networks that maintain internal harmony known as homeostasis. Homeostasis is equilibrium of the internal environment to support all physiological processes for health. Hormone networks can adapt and withstand a certain degree of external excess in the form of too much or too little nutrition or exercise. However there comes a critical point, personal for each individual, where continued excess of unbalanced behaviours will tip over into adverse effects on health. Incidentally in this situation it is not hormones that become unbalanced, rather unbalanced behaviours have forced hormone networks into extensive adaptive changes.

Rebalancing Lifestyle Choices

There are certainly ever emerging challenges for attaining just the right amount and timing of each lifestyle choice around nutrition and exercise. Everyone likes a “quick fix”: apart from your hormones and your health. This is why New Year’s resolutions around extreme dieting or exercise at either end of the spectrum don’t lead to long term benefits. Another problem is that it is difficult to override in-build “safety” mechanisms, so it is challenging psychologically to stick to original intentions. Your body and millions of years of evolution knows best. This can leave you deflated and demotivated. You can’t stick to your plan and this plan does not bring the success you expected. What are the ways to set you on the surest path for optimal heath?

Lifestyle choices for 2023

There are two very important factors in your choice of exercise. Firstly, that this is something you personally enjoy. Studies show that those who chose exercise that they enjoy are more likely to keep exercising and make healthy food choices. My personal favourite is taking a ballet class with my excellent teacher and friends of many years. Dance also covers the second important point about exercise choice in that it should involve different types of fitness. I see many people just focusing on a cardiovascular type of exercise, neglecting strength, flexibility and neuromuscular skills. However, if ballet is not your thing, then choose your exercise types wisely for enjoyment and to cover all bases of fitness.

Nutrition

Nutrition is very similar to exercise in that food choices should cover all the nutritional requirements for the individual and not neglect the enjoyment element of eating. Trying to adhere rigidly to any type of diet that does not encompass these elements will not end well for health in the long run. I see a lot of exercisers who end up in unintentional or intentional low energy availability with associated adaptative down regulation of hormones, which can be challenging to rectify. At the other end of the spectrum, for those who maybe have favoured energy intake over energy expenditure, the type of weight reduction diets that purport to give rapid weight loss, can often be counterproductive in the long term. If it sounds too good to be true, it probably is.

Sleep

“Sleep is the chief nourisher in life’s great feast”. Although Shakespeare did not realise at the time of writing “Macbeth”, sleep certainly is the chief nourisher when it comes to hormones. Many hormone biological clocks, biochronometers, are set according to our sleep patterns with recent research showing that lack of sleep adversely impacts hormone health for men and women. So aiming for good sleep patterns is something relatively straight forward and actionable to support health.

Stress management

We often have our own personal responses to “stress”. This could be responding through an excess of behaviour at either end of spectrum: eating and/or exercising too little or too much. Especially when combined with disrupted sleep patterns, this creates the perfect storm for challenging hormone health. This vicious circle can become a repeating pattern of response to “stress”. I put “stress” in inverted commas intentionally, because “stress” is our personal interpretation of external stressors. We each have our own interpretation of events and our personal response.

For this reason, “stress” management strategies are a personal choice. Identifying your personal triggers for deviating away from balanced behaviours is an important starting point. Then noting what tends to be your typical response is to these triggers. Can you explore more helpful ways to deal with your personal triggers? Is this listening to music, reading, mediation, meeting with friends or as Hippocrates advised going for a walk? I often see people (including myself) who have tendency to over exercise when confronted with stress provoking situations. So, in this case, going for more walks wouldn’t be the best option. Make sure your strategies are personal to you.

Moderation for Optimal Health 2023

The top tip for optimal health in 2023 and beyond is to aim for moderation and balance across the key lifestyle choices of exercise, nutrition and sleep. Combined with your personal stress management strategies to avoid too much or too little of any of these behaviours, this is the surest way to health as Hippocrates advised. If you do need to modify or fine tune your choices, making small changes that you can sustain over the whole year and beyond will bring success in health.

Next steps

“Hormones, Health and Human Potential: A guide to understanding your hormones to optimise your health and performance” is available in paperback and Kindle (illustrations in colour) from Amazon and direct from Sequoia books (ship overseas)

Hormone Health advisory appointments are available

Presentations and workshops

Hormones, Health and Human Potential

25 November 2022

“Hormones, Health and Human Potential” explains how hormones play a crucial role in determining health. Hormone networks provide the feedback mechanism by which our lifestyle and behaviours enable us to reach our personal potential.

Introduction

Over 2,000 years ago Hippocrates advocated that the “safest way to health” was through “the right amount of nourishment and exercise” for “every individual”. As it turns out Hippocrates was way ahead of his time in articulating the principles of personalised and preventative medicine.

Hormones as the missing link to health

Although Hippocrates understood that lifestyle and behaviours are key to health, he did not know why. We now know that hormones are the key players in this vital role. Hormones are instigators in bringing our DNA to life by determining gene expression. Hormones direct the production of proteins, in the optimal amounts and at the right time. Hormones work as networks to maintain mental and physical health.

Lifestyle factors influencing health through hormones networks

Complex internal negative feedback loops between hormones and the biological variables that they regulate, enable homeostasis for good physiological function. Challenges to homeostasis, due to our interactions with the environment are detected by the hypothalamus, which manages hormone network response. In this way there is another layer of feedback loops between lifestyle behaviours and hormones.

Well-balance lifestyle behaviours, in terms of quantity and timing, support healthy hormone network function, leading us to the “safest way to health”. Conversely, circadian misalignment, where lifestyle choices conflict between internal biochronometers, can lead to hormone dysregulation found in conditions such as metabolic syndrome.

Harnessing hormones as preventative and supportive medicine

A good balance of lifestyle factors can harness hormones as a form of supportive and preventative medicine. This is particularly relevant for type 2 diabetes mellitus and metabolic syndrome. For women, where there are physiological changes in hormones, such as occurs at menopause, attendant symptoms and impacts on long term health can be mitigated by lifestyle as part of the management of menopause. For example, exercise has been shown to have a beneficial effect on temperature regulation, metabolism, body composition, bone health and reducing the risk of breast cancer.

Athlete performance mediated by hormones

Hormones mediate the positive adaptive changes due to exercise training. Understanding these mechanisms can benefit both athletes and patients .

Imbalances in behaviours causing hormone dysregulation

Too little exercise and excess nutrition can lead to hormone dysregulation, seen in metabolic syndrome and type 2 diabetes mellitus. On the other hand, too much of a “good thing” can also cause health and performance issues in exercisers. Relative energy deficiency in sport (RED-S) can occur in exercisers of all ages and levels, where there is either an unintentional or intentional mismatch between energy intake and energy demand. Consequent low energy availability causes hormone network disruption, which in the long-term results in adverse effects on both health and performance .

Conclusions

• Hormone network function plays an important role in mental and physical health
• Hormones are influenced by our lifestyle behaviours of exercise, nutrition and sleep
• The benefits of lifestyle behaviours are derived from the positive adaptive changes driven by hormones
• Imbalances in lifestyle behaviours can cause hormone disruption leading to adverse effects on health and exercise performance

References

Keay N. Health Hormones and Human Potential. Sequoia books. 2022

McCarthy O, Pitt J, Keay N et al Passing on the exercise baton: What can endocrine patients learn from elite athletes? Clinical Endocrinology 2022 96;(6):781-792

Keay N, Francis G Infographic. Energy availability: concept, control and consequences in relative energy deficiency in sport (RED-S) British Journal of Sports Medicine 2019;53:1310-1311.

Energy Availability: Concept, Control and Consequences in relative energy deficiency in sport (RED-S)

24 May 2019

Relative energy deficiency in sport (RED-S) is an issue of increasing concern in sports and exercise medicine. RED-S impact exercisers of all levels and ages, particularly where low body weight confers a performance or aesthetic advantage. Key to mitigating adverse health and performance consequences of RED-S is supporting athletes and dancers to change behaviours. These infographics aim to assist clinicians in communicating the concepts to exercisers and in implementing effective management of athletes in their care[1].

Figure 1 illustrates the concept of energy availability (EA) in RED-S. Preferentially energy derived from dietary intake covers the demands of training and the remaining energy, EA, is, quantified in Kcal/Kg of fat free mass[2]. In Figure 1, the central bar illustrates adequate EA in an athlete where energy intake is sufficient to cover the demands of training and fundamental life processes to maintain health. Conversely, low energy availability (LEA) is a situation of insufficient EA to cover basic physiological demands. LEA leads to the adverse consequences of RED-S[3]. LEA can arise unintentionally or intentionally, due to a mismatch between energy intake and energy requirement. In Figure 1 the bar on the left shows LEA resulting from reduced energy intake with maintained training load. On the right, LEA is a consequence of increased training load with maintained energy intake.

Figure 2 illustrates that EA is under the control of an athlete[4]. The three behaviours relating to training, nutrition and recovery determine EA. Integrated periodisation of these behaviours results in optimal health and performance. Conversely, an imbalance in these behaviours results in suboptimal functionally. LEA in the case of high training loads relative to nutritional intake. Thus, this figure reinforces the important point in the IOC statements on RED-S that psychological factors which determine these behaviours are key in both the development, continuation and management of RED-S[2,3].

Figure 2 also shows the temporal, synergistic effect of these behaviours to ensure a fully functioning endocrine system. Hormones are key for health and to drive positive adaptations to exercise, to improve athletic performance. Thus hormones can be informative in tracking the response of an individual to these three input variables. Furthermore, endocrine markers relate to the RED-S clinical outcome of stress fracture in athletes, being more reliable as objective, quantifiable indicators of EA than numerical calculation of EA from direct assessment[5].

Authors

Nicola Keay¹, Gavin Francis²

¹ Department of Sport and Exercise Sciences, Durham University

²Science4Perforamnce, London

Br J Sports Med 2019;0:1–2. doi:10.1136/bjsports-2019-100611

References

1 http://health4performance.co.uk (accessed 21/01/2019) Health4Performance Educational BASEM website raising awareness of RED-S Working group on RED-S British Association of Sport and Exercise Medicine 2018

2 Mountjoy M, Sundgot-Borgen J, Burke L et al. IOC consensus statement on relative energy deficiency in sport (RED-S): 2018 update Br J Sports Med2018;52(11):687-697

3 Mountjoy M, Sundgot-Borgen J, Burke L et al. The IOC consensus statement: beyond the Female Athlete Triad–Relative Energy Deficiency in Sport (RED-S). Br J Sports Med2014;48(7):491-7

4 Burke L, Lundy B, Fahrenholtz L et al, & Melin. Pitfalls of conducting and interpreting estimates of energy availability in free-living athletes. International Journal of Sport Nutrition and Exercise Metabolism2018; 28(4):350–363. https://doi.org/10.1123/ijsnem.2018-0142

5 2Heikura I, Uusitalo A, Stellingwerff T et al. 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 Metabolism2018; 28(4):403–411. https://doi.org/10.1123/ijsnem.2017-0313

Raising Awareness of RED-S in Male and Female Athletes and Dancers

11 October 2018

Health4Performance is a recently developed BASEM open access educational resource

This is a world premier: a resource developed for and by athletes/dancers, coaches/teachers, parents/friends and healthcare professionals to raise awareness of Relative Energy Deficiency in Sport (RED-S)

What?

Optimal health is required to attain full athletic potential. Low energy availability (LEA) can compromise health and therefore impair athletic performance as described in the RED-S clinical model.

Dietary energy intake needs to be sufficient to cover the energy demands of both exercise training and fundamental physiological function required to maintain health. Once the energy demands for training have been covered, the energy left for baseline “housekeeping” physiological function is referred to as energy availability (EA). EA is expressed relative to fat free mass (FFM) in KCal/Kg FFM. The exact value of EA to maintain health will vary between genders and individuals, roughly equivalent to resting metabolic rate of the individual athlete/dancer. LEA for an athlete or dancer will result in the body going into “energy saving mode” which has knock on effects for many interrelated body systems, including readjustment to lower the resting metabolic rate in the longer term. So although loss in body weight may be an initial sign, body weight can be steady in chronic LEA due to physiological energy conservation adaptations. Homeostasis through internal biological feedback loops in action.

The most obvious clinical sign of this state of LEA in women is cessation of menstruation (amenorrhea). LEA as a cause of amenorrhoea is an example of functional hypothalamic amenorrhoea (FHA). In other words, amenorrhoea arising as a result of an imbalance in training load and nutrition, rather than an underlying medical condition per se, which should be excluded before arriving at a diagnosis of FHA. All women of reproductive age, however much exercise is being undertaken, should have regular menstrual cycles, which is indicative of healthy hormones. This explains why LEA was first described as the underlying aetiology of the female athlete triad, as women in LEA display an obvious clinical sign of menstrual disruption. The female athlete triad is a clinical spectrum describing varying degrees of menstrual dysfunction, disordered nutrition and bone mineral density. However it became apparent that the clinical outcomes of LEA are not limited to females, nor female reproductive function and bone health in female exercisers. Hence the evolution of the clinical model of RED-S to describe the consequences of LEA on a broader range of body systems and including male athletes.

A situation of LEA in athletes and dancers can arise unintentionally or intentionally. In the diagram below the central column shows that an athlete where energy intake is sufficient to cover the demands from training and to cover basic physiological function. However in the column on the left, although training load has remained constant, nutritional intake has been reduced. This reduction of energy intake could be an intentional strategy to reduce body weight or change body composition in weight sensitive sports and dance. On the other hand in the column on the right, training load and hence energy demand to cover this has increased, but has not been matched by an increase in dietary intake. In both these situations, whether unintentional or intentional, the net results is LEA, insufficient to maintain health. This situation of LEA will also ultimately impact on athletic performance as optimal health is necessary to realise full athletic potential.

Although LEA is the underlying aetiology of RED-S, there are many methodological and financial issues measuring LEA accurately in “free living athletes“. In any case, the physiological response varies between individuals and depends on the magnitude, duration and timing of LEA. Therefore it is more informative to measure the functional responses of an individual to LEA, rather than the value calculated for EA. As such, Endocrine markers provide objective and quantifiable measures of physiological responses to EA. These markers also reflect the temporal dimension of LEA; whether acute or chronic. In short, as hormones exert network effects, Endocrine markers reflect the response of multiple systems in an individual to LEA. So by measuring these key markers, alongside taking a sport specific medical history, provides the information to build a detailed picture of EA for the individual, with dimensions of time and magnitude of LEA. This information empowers the athlete/dancer to modify the 3 key factors under their control of training load, nutrition and recovery to optimise their health and athletic performance.

Why?

Who is at risk of developing RED-S? Any athlete involved in sports or dance where being light weight confers a performance or aesthetic advantage. This is not restricted to elite athletes and dancers. Indeed the aspiring amateur or exerciser could be more at risk, without the benefit of a support team present at professional level. Young athletes are at particular risk during an already high energy demand state of growth and development. Therefore early identification of athletes and dancers at risk of LEA is key to prevention of development of the health and performance consequences outlined in the RED-S clinical model. Although there is a questionnaire available for screening for female athletes at risk of LEA, more research is emerging for effective and practical methods which are sport specific and include male athletes.

How?

Early medical input is important as RED-S is diagnosis of exclusion. In other words medical conditions per se need to be ruled out before arriving at a diagnosis of RED-S. Prompt medical review is often dependent on other healthcare professionals, fellow athletes/dancers, coaches/teachers and parents/friends all being aware and therefore alert to RED-S. With this in mind, the Health4Performance website has areas for all of those potentially involved, with tailored comments on What to look out for? What to do? Ultimately a team approach and collaboration between all these groups is important. Not only in identification of those at risk of LEA, but in an integrated support network for the athlete/dancer to return to optimal health and performance.

References

Heath4Performance BASEM Educational Resource

Video introduction to Health4Performance website

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

What is Dance Medicine? BJSM 2018

Identification and management of RED-S Podcast 2018

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

How to Identify Male Cyclists at Risk of RED-S? 2018

Pitfalls of Conducting and Interpreting Estimates of Energy Availability in Free-Living Athletes IJSNM 2018

Low Energy Availability Is Difficult to Assess but Outcomes Have Large Impact on Bone Injury Rates in Elite Distance Athletes IJSNM 2017

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

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

What is Dance Medicine?

22 July 2018

Traditionally dance medicine has been somewhat the poor relation of sports medicine. Why is this the case? There is no doubt that dancers, of whatever genre, require the physical and psychological attributes of athletes. However, dance involves an additional artistic component where ultimately performance on stage is judged not according to a score card as in aesthetic sports, rather on the ability of the dancers to forge an emotional connection with the audience.

As with athletes, injuries are always an important topic for dancers: how to recognise the aetiology of injuries and thus develop prevention strategies. Dance UK have published two reports on national enquiries into the health of dancers. Dance UK has now evolved into the organisation One Dance which includes the National Institute of Dance Medicine and Science (NIDMS). One Dance provides delivery of the Healthier Dancer Programme (HDP) whose talks regularly engage 1500+ dancers and dance professionals per year and which will be a part of the One Dance UK conference at the end of November, an overarching event for the entire dance sector. One Dance holds a list of healthcare professionals with experience and expertise in dance. One Dance is an especially an important resource for independent dancers who will not have access to the provision for those working in larger dance companies.

However, beyond injury management, there are important aspects of the health of dancers which need to be considered, highlighted in an information booklet “Your body, Your risk” from Dance UK. The female athlete triad is well established as a clinical spectrum comprising of disordered eating, menstrual dysfunction and impaired bone health. Indeed impaired bone mineral density many persist even after retirement in female dancers. The recent evolution of the female athlete triad into relative energy deficiency in sports (RED-S) provides an important clinical model. RED-S includes male athletes/dancers, involves multiple body systems and crucially, evidence of detrimental effects on athletic performance is being researched and described. In other words RED-S is not restricted to female dancers/athletes with bone stress injuries.

BalletDials — Integrated periodisation of training, nutrition and recovery support perforamnce

The fundamental cause of RED-S is low energy availability where nutritional intake is insufficient to cover energy requirements for training and resting metabolic rate. In this situation the body goes into energy saving mode, which includes shut down of many hypothalamic-pituitary axes and hence endocrine network dysfunction. As hormones are crucial to backing up adaptations to exercise training, dysfunction will therefore have an effect not just on health, but on athletic performance. In dance, neuromuscular skills and proprioception are key for performance. Hence, of concern is that these skills are adversely impacted in functional hypothalamic amenorrhoea, which together with impaired bone health from RED-S, greatly increases injury risk.

Low energy availability can arise in dance and sport where low body weight confers an aesthetic and/or performance advantage. There is no doubt that being light body weight facilitates pointe work in female dancers and ease of elevation in male dancers. Thus, low energy availability can occur intentionally in an effort to achieve and maintain low body weight. Low energy availability can also be unintentional as a result of increased expenditure from training, rehearsal and performance demands and the practicality of fuelling. This situation is of particular concern for young dancers in training, as this represents a high energy demand state, not just for full time training, additionally in terms of energy demands for growth and development, including attainment of peak bone mass.

Despite the significance of RED-S in terms of negative consequences on health and performance, as outlined by the IOC in the recent consensus update, further work is required in terms of raising awareness, identification and prevention. Fortunately these issues are being addressed with the development of an online educational resource on RED-S for athletes/dancers, their coaches/teachers/parents and healthcare professionals which is backed by British Association of Sport and Exercise Medicine (BASEM) and with input from One Dance and NIDMS. In terms of research to facilitate the proliferation of evidence base in dance medicine, One Dance lists calls for research, whilst NHS NIDMS clinics provide access to clinical dance medicine. The importance of the application of this growing field of dance medicine and science for the health and performance of dancers was recently outlined in an article “Raising the barre: how science is saving ballet dancers“.

On the international stage, the International Association for Dance Medicine & Science (IADMS) strives to promote an international network of communication between dance and medicine. To this end, IADMS will hold its 28th Annual Conference in Helsinki, Finland from October 25-28, 2018. In addition to extensive discussion of dance injuries, there will be presentations on “Sleep and Performance” and “Dance Endocrinology”.

So maybe Dance Medicine and Science is not so much the poor relation of Sports Medicine, rather showing the way in terms of integrating input between dancers, teachers and healthcare professionals to optimise the health of dancers and so enable dancers to perform their full potential.

References

Presentations

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

Fit to Dance 2 Dance UK

One Dance

Your body your risk. Dance UK

Fit but fragile. National Osteoporosis Society

Bone mineral density in professional female dancers N. Keay, BJSM

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

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

Dancing through Adolescence Dr N Keay BJSM

Healthy Hormones Dr N Keay BASEM 2018

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

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

Raising the barre: how science is saving ballet dancers The Guardian 2018

International Association for Dance Medicine and Science Medicine & Science in Sports and Exercise

Relative Energy Deficiency in Sport (RED-S) 2018 update

24 May 2018

What updates are presented in the IOC consensus statement on RED-S 2018?

Prevention

Awareness is the key to prevention. Yet RED-S continues to go unrecognised. Less than 50% of clinicians, physiotherapists and coaches are reported as able to identify the components of the female athlete triad. In a survey of female exercisers in Australia, half were unaware that menstrual dysfunction impacts bone health. Note that these concerning statistics relate to the female athlete triad. Lack of awareness of RED-S in male athletes is even more marked. RED-S as a condition impacting males, as well as females, was described in the initial IOC consensus statement published in 2014. However there is evidence of the occurrence of RED-S in male athletes pre-dating this.

Identification

Identifying an athlete/dancer with RED-S is not always straight forward. In dance or sports where being light weight confers a performance or aesthetic advantage, how can a coach/teacher distinguish between athletes who have this type of physique “naturally” and those who have disordered eating and are at risk of RED-S? Equally, low energy availability could be a result either of intentional nutrition restriction to control body weight and composition, or an unintentional consequence of not matching an increase in energy expenditure (due to increased training load), with a corresponding increase in energy intake.

Performance effects

Performance is paramount to any athlete or dancer. Apart from physical ability, being driven and determined are important characteristics to achieve success. If weight loss is perceived as achieving a performance advantage, then this can become a competitive goal in its own right: in terms of the individual and amongst teammates. This underlies the interactive effect of psychological factors in the development and progression in the severity of RED-S.

There is both theoretical and practical evidence that short term low energy availability impairs athletic performance as the body is less able to undertake high quality sessions and benefit from the physiological adaptations to exercise. Within day energy deficits have been shown to have adverse effects in both male and female athletes in terms of impact on oestradiol/testosterone and cortisol concentrations. Failure to refuel with carbohydrate and protein promptly after a training session in male runners has been shown to have an adverse effect on bone turnover markers.

To underline the adverse performance effect of low energy availability, a recent study demonstrated that in female athletes, those with functional hypothalamic amenorrhea displayed decreased neuromuscular performance compared to their eumenorrhoeic counterparts. This adverse effect on performance is of particular concern where such skills are crucial in precisely those sports/dance where RED-S is most prevalent. Clearly this situation puts such athletes at increased injury risk, especially if associated with adverse bone mineral density (BMD) due to low energy availability.

Ironically the long term consequences of low energy availability produce adverse effects on body composition: increased fat/lean and reduction in BMD. In other words, the precise opposite effects of what an energy restricted athlete is trying to achieve. In terms of bone health, the lumbar spine is most sensitive to nutrition/endocrine factors (apart from rowers where mechanical loading can attenuate BMD loss at this site in RED-S). Suboptimal BMD is associated with an increased risk of bone injury and therefore impaired performance.

Medical Assessment

Low energy availability is the fundamental issue driving the multi-system dysfunction in the endocrine, metabolic, haematological, cardiovascular, gastrointestinal, immunological and psychological systems in RED-S. However, there are practical issues with directly quantifying energy availability as this is subject to the inaccuracies of reliably measuring energy intake and output. Endocrine and metabolic markers have been shown to more objective indicators of low energy availability, which in turn are correlated to performance outcomes such as bone stress injury in male and female athletes. In the case of female athletes there is an obvious clinical indicator of sufficient energy availability: menstrual cycles. As there is no such obvious clinical sign in male athletes is this why RED-S is less frequently recognised? In both female and male athletes there is some degree of clinical variation: there is no absolute threshold cut off with a set temporal component of low energy availability resulting in amenorrhoea or low testosterone in males. Therefore the IOC recommends that individual clinical evaluation include discussion of nutrition attitudes and practices, combined with menstrual history for females and endocrine markers for male and female athletes will give a very clear indication if an athlete is at risk of/has RED-S.

Management

RED-S is a diagnosis of exclusion. Once medical conditions per se have been excluded, RED-S presents a multi-system dysfunction caused by a disrupted periodisation of nutrition/training/recovery. For an athlete the motivation to address these imbalances is to be in a position reach their full athletic potential. This attainment is compromised in RED-S.

Pharmacological interventions are not recommended as first line management in amenorrhoeic athletes. Oral contraception (OCP) masks amenorrhoea with withdrawal bleeds. OCP does not support bone health and indeed may exacerbate bone loss by suppressing further IGF-1. Although transdermal oestrogen, combined with cyclic progesterone does not down regulate IGF-1, nevertheless any hormonal intervention cannot be a long term solution, as bone loss will continue if energy availability is not addressed as a priority.

What next?

The IOC statement suggests further research should include studies with allocation of athletes to intervention groups, with assessment of effects over a substantial time period. Currently a study of competitive male road cyclists over a training/competition season is being undertaken to evaluate the effects of nutrition advice and off bike skeletal loading exercise. Crucially outcome measures will not only be based on bone health and endocrine markers, but measures of performance in terms of power production and race results.

To raise awareness and build support pathways as recommended in the IOC statement, this is an on going process which requires communication between athlete/dancers, coaches/teachers, parents and healthcare professionals both medical and non medical working with male and female athletes.

References

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

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

Male Athletes: the Bare Bones of Cyclists

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

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

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

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

Reduced Neuromuscular Performance in Amenorrheic Elite Endurance Athletes Medicine & Science in Sports & Exercise. 49(12):2478–2485, DEC 2017

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

Cyclists: Make No Bones About It BJSM 2018

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

Part 2: Health, Hormones and Human Performance take centre stage BJSM 2018

Cyclists: How to Support Bone Health?

Healthy Hormones BASEM 2018

Health, Hormones and Human Performance Part 2

8 April 2018

Endocrine and Metabolic aspects of Sports and Exercise Medicine are crucial determinants of health and human performance, from reluctant exerciser through to elite athlete and professional dancer. This is what the recent BASEM spring conference set out to demonstrate. The previous blog described functional disruption of Endocrine networks caused by non-integrated periodisation of the three key lifestyle factors of exercise/training, nutrition and recovery/sleep, can lead to adverse effects on health and athletic performance.

Integrated periodisation of exercise, nutrition, recovery for optimisation of health and performance (Keay BJSM 2017)

Grace, aesthetic line and ethereal quality belie the athletic prowess required in ballet. What are the Endocrine, metabolic and bone health consequences for this unique group of athletes? Dr Roger Wolman (Medical Advisor to National Institute for Dance Medicine and Science) returned to the important topic of insufficient energy availability in sport/dance where being lightweight confers a performance advantage, resulting in dysfunction in multiple endocrine axes. Dr Wolman discussed his recent research studies in dancers revealing an intriguing synergistic action between oestrogen and vitamin D, which is itself a steroid hormone. Evidence was presented to demonstrate how being replete in vitamin D has beneficial effects on bone, immunity and muscle function. Thus it is key in preventing injury and supporting health in athletes, with particular relevance in premenarchal and postmenopausal women, who are in relative oestrogen deficient states. This presentation will certainly change my clinical practice and, I am sure, that of many in the audience, in ensuring that athletes/patients are vitamin D replete. This may have to be achieved in the form of strategic use of sports informed vitamin D supplementation, given that even walking naked for 5 hours a day outside during UK winter, would not stimulate enough vitamin D production. Therefore, to the relief of many in the audience, Dr Wolman did not recommend this strategy.

Dr Kate Ackerman (member of RED-S IOC working group) explained why we should all tap into our inner endocrinologist. Sport and Exercise Medicine (SEM) goes far beyond diagnosing and treating injury. Is there any underlying endocrine cause for suboptimal health, performance or injury? Be this an endocrine diagnosis that should not be missed, or a functional endocrine dysfunction due to relative energy deficiency in sports (RED-S). Dr Ackerman explained the importance of the multidisciplinary team in both identifying and supporting an athlete experiencing the consequences of RED-S. New research from Dr Ackerman’s group was presented indicating the effects of RED-S on both health and athletic performance.

Females now have combative roles alongside their male counterparts. What are the implications of this type of intensive exercise training? Dr Julie Greaves (Research Director of the ministerial women in ground close combat research programme) presented insightful research revealing that differences in the geometry of bone in men and women can predispose towards bone stress injury and account for increased incidence in this type of injury in female recruits.

Lunchtime discussion and debate was focused on the determinants of athletic gender, lead by Dr Joanna Harper and Professor Yannis Pitsiladis (International Federation of Sports Medicine). Rather than relying on genetic sex, testosterone concentration was proposed as the criteria for determining whether an athlete competes in male or female events. That testosterone concentration is linked to performance was demonstrated in a study published last year in the BMJ where female athletes in the upper tertile of testosterone were shown to have a performance advantage in certain strength based track and field disciplines. This could potentially be an objective, functional metric used to determine sporting categories for transgender and intersex athletes. The only current uncertainty is how previously high levels of testosterone seen in male, or intersex athletes would have already had an impact on physiology, if this athlete then wished to compete as female and therefore lower testosterone levels with medication.

Nutrition is a key component in optimising health and performance through the Endocrine system. Dr Sophie Killer (English Institute of Sport) explained practical implications for athletes. In a study stimulating a training camp, there were distinct differences between athletes on different regimes of carbohydrate intake in terms of endocrine markers and psychological effects. Those athletes on restricted carbohydrate intake fared worse.

Insulin insensitivity is the underlying pathological process in developing type 2 diabetes mellitus (T2DM) and metabolic syndrome. What is the crucial lifestyle intervention to combat this? Dr Richard Bracken (Swansea University) presented the science behind why and how exercise improves blood glucose control and therefore ultimately risk of developing the macro and microvascular complications of diabetes. T2DM is an increasing health issue in the population, which has to be addressed beyond reaching for the prescription pad for medication. Dr Bracken outlined some effective strategies to encourage the reluctant exerciser to become more active. Having worked myself in NHS diabetic clinics over many years, this was a key presentation at the conference to demonstrate that SEM goes far beyond a relatively small group of elite athletes. Highlighting the crucial role of physical activity in supporting health and performance through optimisation of endocrine networks: uniting the elite athlete and the reluctant exerciser.

One road to Rome — One Road to Rome (BJSM Keay 2017)

Motivate2Move initiative aims to shift the emphasis from treating disease, to preventing disease. Dr Brian Johnson presented the excellent resource for healthcare professionals to encourage, motivate and educate patients in order to consider exercise as an effective and enjoyable way to improve health.

Hormones play a key role in health and human performance, applicable to all levels of exerciser from reluctant exerciser to elite athlete.

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