Health, Hormones and Human Performance Part 1

How hormones determine health and athletic performance

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 I set out to demonstrate as the chair of the recent British Association of Sport and Medicine conference, with insightful presentations from my colleagues whom I had invited to share their research and practical applications of their work. The audience comprised of doctors with interest in sport and exercise medicine, representatives from the dance world, research scientists, nutritionists, physiotherapists, coaches and trainers. In short, all were members of multi-disciplinary teams supporting aspiring athletes. The importance of the conference was reflected in CDP awards from FSEM, BASES, Royal College of Physicians (RCP), REP-S and endorsement for international education from BJSM and National Institute of Dance Medicine and Science (NIDMS).

Exercise is a crucial lifestyle factor in determining health and disease. Yet we see an increasing polarisation in the amount of exercise taken across the general population. At one end of the spectrum, the increasing training loads of elite athletes and professional dancers push the levels of human performance to greater heights. On the other side of the spectrum, rising levels of inactivity, in large swathes of the population, increase the risk of poor health and developing disease states. Which fundamental biological processes and systems link these groups with apparently dichotomous levels of exercise? What determines the outcome of the underlying Endocrine and metabolic network interactions? How can an understanding of these factors help prevent sports injuries and lead to more effective rehabilitation? How can we employ Endocrine markers to predict and provide guidance towards beneficial outcomes for health and human performance?

If you weren’t able to come and participate in the discussion, these are some topics presented. My opening presentation (see video below) set the scene, outlining why having an optimally functioning Endocrine system is fundamental to health and performance. Conversely, functional disruption of Endocrine networks occurs with non integrated periodisation of the three key lifestyle factors of exercise/training, nutrition and recovery/sleep, which can lead to adverse effects on health and athletic performance.

In the case of an imbalance in training load and nutrition, this can manifest as the female athlete triad, which has now evolved into relative energy deficiency in sports (RED-S) in recognition of the fact that Endocrine feedback loops are disrupted across many hormonal axes, not just the reproductive axis. And, significantly, acknowledging the fact that males athletes can also be impacted by insufficient energy availability to meet both training and “housekeeping” energy requirements. Why and how RED-S can affect male athletes, in particular male competitive road cyclists, was discussed, highlighting the need for further research to investigate practical and effective strategies to optimise health and therefore ultimately performance in competition.

A degree of overlap and interplay exists between RED-S (imbalance in nutrition and training load), non functional over-reaching and over-training syndrome (imbalances in training load and recovery). Indeed research evidence was presented suggesting that RED-S increases the risk of developing over-training syndrome. In these situations of functional disruption of the Endocrine networks, underlying Endocrine conditions per se should be excluded. Case studies demonstrated this principle in the diagnosis of RED-S. This is particularly important in the investigation of amenorrhoea. All women of reproductive age, whether athletes or not, should have regular menstruation (apart from when pregnant!), as a barometer of healthy hormones. Indeed, since hormones are essential to drive positive adaptations to exercise, healthy hormones are key in attaining full athletic potential in any athlete/dancer, whether male or female. Evidence was presented from research studies for the role of validated Endocrine markers and clinical menstrual status in females as objective and quantifiable measures of energy availability and hence injury risk in both male and female athletes.

Triumvirate of external factors impacting Endocrine system and hence performance

Alongside training metrics, if female athletes recorded menstrual pattern (as Gwen Jorgensen recently showed on her Training Peaks) and all athletes kept a biological passport of selected Endocrine markers; this could potentially identify at an early stage any imbalances in the triumvirate of training load, nutrition and recovery. Pre-empting development of RED-S or over-training syndrome, supports the maintenance of healthy hormones and hence optimal human performance.

Look out for presentations from speakers which will be uploaded on BASEM website shortly.


Video of presentation on the Endocrine and Metabolic Aspects of Sports and Exercise Medicine BASEM conference “Health, Hormones and Human Performance”

Study of hormones, body composition, bone mineral density and performance in competitive male road cyclists Investigation of effective and practical nutrition and off bike exercise interventions

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




Hormones and Sports Performance


The interactive network effects of the Endocrine system are key in producing effective adaptations to exercise. This in turn results in improved sport performance. Athletes are aware of the crucial role of the Endocrine system in sports performance. Therefore it is not surprising that, on the World Anti-Doping agency (WADA) banned list, the majority of prohibited substances both in and out of competition are hormones, mimetics and hormone and metabolic modulators. In 2013 hormones accounted for 75% of all adverse analytical findings. Use of such substances to enhance performance is not only illegal and against the spirit of sport, but also potentially harmful to the health of the athlete.

Considering some of these prohibited hormones, the usual suspects start with anabolic agents: anabolic androgenic steroids whether these be synthetic derivatives taken exogenously or molecular identical endogenous steroids, including metabolites and isomers, administered exogenously.  In a study recently published in the BJSM, female athletes with free testosterone levels in the highest tertile displayed better performance than those in lowest tertile of up to 4.5% in certain power/anaerobic events such as 400m, 800m, hammer and pole jump. This may be due to associated body composition with increased lean mass and “risk taking” behaviour. In 2015, the Court of Arbitration for Sport ruled that the IAAF should suspend the existing upper limit on female athlete testosterone, of 10nmol/l, because at the time there was insufficient evidence that such levels would improve performance in female athletes. In view of the results of this study, the situation may have to be reviewed. This is clearly an ethical dilemma regarding intersex athletes, whose hyerandrogenism is due to endogenous biological factors.

Next up there are peptide hormones/growth factors/mimetics. As previously discussed, growth hormone (GH) proved a challenging peptide hormone for which to develop a dope test. Firstly what are the “normal” ranges for elites athletes, seeing as exercise and sleep are the two major stimuli for GH release? Furthermore, elite athletes represent a subset of the population, for whom the normal range may differ. Secondly exogenous genetically engineered GH is to all intents and purposes identical to endogenous secreted GH, with a relatively short half life. Hence early on in development of a dope test we realised that downstream markers, particularly of bone turnover would have to be used. This brings the discussion to erythropoietin (EPO). In a similar way to GH and allied releasing factors, increases in key surrogate variables producing performance enhancement are measured. In the case of exogenous EPO these are changes in haemoglobin and haematocrit as recorded in an athletes’ biological passport. A recent study on amateur cyclists given EPO in a double blind randomised placebo controlled trial, reported no improvement in a submaximal field test. Although the effects in elite cyclists would arguably be more relevant, this is not possible for obvious ethical reasons. Nevertheless the effects on elite cyclists during maximal efforts, for example in an attack on a mountainous stage in the Tour de France, would not necessarily correlate to amateurs in submaximal conditions, where there may be other limiting factors to performance. In addition athletes may use supraphysiological dosing regimens (“stacking” or “pyramiding”), not necessarily comparable to those used in clinical studies. In my opinion, apart from potential ergogenic benefits, whatever the degree, the intention to “take a short cut” to improve performance is the issue, not to mention the adverse health sequelae, for example, the study noted a thrombotic tendency with EPO, even in modest doses.

Hormone and metabolic modulators have received attention following the fall from grace of Maria Sharapova. Meldonium which is licensed for use in Baltic countries has beneficial anti-ischaemic effects in cardiovascular, neurological and metabolic disease states. Apparently this drug was use amongst Soviet troops during the war in mountainous Afghanistan. Amongst athletes the intended purpose is to improve endurance exercise performance and recovery post exercise. This is an example where an unfortunate spin off from developing drugs to treat disease states, is that such drugs are also see by some athletes as a short cut to enhance sport performance.

Although thyroxine is not on the banned list, there are certainly arguments that exogenous thyroxine should not be given to athletes, unless there is definitive biochemical evidence that the athlete suffers with hypothyroidism: as defined by criteria for diagnosing this condition with consistently elevated thyroid stimulating hormone (TSH) above the normal range, with paired low T4. Thyroid autoantibodies may also provide extra clinical information. The effect of intense training on the hypothalamic-pituitary-thyroid axis is to slightly suppress both TSH and T4, whilst these remain in the normal range. In this instance medicating with exogenous thyroxine would be to support recovery from training, rather than to legitimately treat a proven medical condition. In a similar way a TUE is only justified for testosterone in pathological disorders of the hypothalamo-pituitary-testicular axis and not for suppressed testosterone as a result of training stress.

Unfortunately supplements are a source of preventable anti-doping rule violations (ADRV) representing up to half of the total ADRVs. Either such supplements have not listed all the contents, or contamination has occurred during manufacture. If an athlete wishes to take supplements, certainly it is advisable only to take reliably tested products. Nevertheless even if an athlete unintentionally ingests prohibited substances, then ultimately they are still liable. If claims of the benefits of such supplements sound too good to be true, they probably are. Ultimately supplements will not win races and there is no substitute for periodised training, nutrition and recovery.

Effectively there is an arms race between would-be doper and medical expertise in Sports Endocrinology. However, freezing samples for potential re-analysis with emerging understanding and technology in the future is an added deterrent for athletes whose intention is to take a short cut to improving sport 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


Endocrine system: balance and interplay in response to exercise training

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

Enhancing Sport Performance: Part 1 Dr N. Keay, British Association of Sport and Exercise Medicine 2017

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

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

Enabling Sport Performance: part 2

Enhancing Sports Performance: part 3

World Anti-Doping Agency

Serum androgen levels and their relation to performance in track and field: mass spectrometry results from 2127 observations in male and female elite athletes British Journal of Sports Medicine

Doping Status of DHEA Treatment for Female Athletes with Adrenal Insufficiency Clinical Journal of Sports Medicine 2017

Testosterone treatment and risk of venous thromboembolism: population based case-control study British Medical Journal 2016

Effects of erythropoietin on cycling performance of well trained cyclists: a double-blind, randomised, placebo-controlled trial The Lancet, Haematology 2017

Meldonium use by athletes at the Baku 2015 European Games. Adding data to Ms Maria Sharapova’s failed drug test case British Journal of Sports Medicine 2016

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

Australian Sport Anti-Doping Authority