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

28 Apr, 17 | by BJSM

By Dr Nicky Keay

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

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

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


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

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

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

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


Sport Performance and RED-S, insights from recent Annual Sport and Exercise Medicine and Innovations in Sport and Exercise Nutrition Conferences British Journal of Sports Medicine 17/3/17

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

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

Optimal Health: Including Male Athletes! Part 2 – REDs British Journal of Sport Medicine 4/4/17

Optimal Health: Young athletes! Part 3 Consequences of RED-S British Association Sport and Exercise Medicine 13/4/17

Optimal Health: All Athletes! Part 4 Mechanisms of RED-S British Association Sport and Exercise Medicine 13/4/17

Enhancing sport performance: part 1

Enhancing sports performance: part 3

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

Sleep for health and sports performance British Journal of Sport Medicine

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

Clusters of athletes

Inflammation: why and how much?

Successful ageing

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

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

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

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

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

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

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

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

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

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

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

Key words: adaptationamenorrhoeadoping in sport ,Endocrine systemendocrinologyexercisefemale athlete triadfitnessgrowth hormonehealthhormonesinjury, REDssporttraining

What can we learn from Zlatan Ibrahimovic’s knee injury? Focus on PCL implications

26 Apr, 17 | by Karim Khan

The PCL gets much less attention than its anterior partner. What might be going through Zlatan’s mind?

If we start with a player who has suffered an isolated mild to moderate (Grade I-II) PCL injury, we find the player can do well with quality physiotherapy reahabilitation because because surgical reconstruction tends to improve the grade of instability but it does not provide the player with a normal knee.  Acute PCL injuries with bony avulsions are treated surgically. Most isolated Grade III lesions can be treated non-operatively using a specially designed PCL brace that holds the tibia in an anterior reduced position that gives the PCL an opportunity to heal.  Unlike the common intra-articular ACL tear, acute isolated PCL injuries can heal.

Unfortunately, Zlatan appears to have both an ACL and a PCL tear 

In the case at hand, it is NOT an isolated PCL injury. Media reports suggest Ibrahimovic also had an ACL injury (with the possibility of posterolateral corner injury not being mentioned but still present)  A multi-ligament injury has the potential of neuromuscular injury which, when present, has an ominous prognosis. Even without that complication, the prognosis must be very guarded for an elite level football player to return to the demands of high level play with an ACL/ PCL reconstruction.

My goal when seeing similar patients is to ensure they have a stable knee they can walk on and live with. There are anecdotal reports of athletes returning to play after multiple ligament knee reconstruction but when scrutinised, the players are usually the slower lumbering players like football lineman — not players whose success relies on them being quick and agile.

It’s important for the clinicians involved to spend lots of time explaining prognosis to players who suffer serious injury and the rehabilitation team must communicate well and work together.

Professor Mark Hutchinson was a member of the United States Olympic Games sports medicine team at the Rio de Janeiro (2016) and has provided care to the leading teams in the Chicago region for over 20 years. He is a BJSM Senior Associate Editor and you can listen to him on two knee-related podcasts here:

1) Does everyone who ruptures her/his ACL need a knee reconstruction? 

2) Does arthroscopy benefit the patient with knee pain and a proven meniscal tear on MRI?

Oh yeah, almost forgot…

Professor Hutchinson is the star of BJSM’s YouTube page where his pearls on how to examine the knee, shoulder, hip, groin have been viewed over 6 million times. Thanks Hutch!

A postgraduate perspective of a SEM training programme for undergraduates

24 Apr, 17 | by BJSM

Undergraduate perspective on Sport & Exercise Medicine – a BJSM blog series

By Andrew Shafik (@aaashafik), Guy Evans (@drguyevans) and Ajai Seth (@ajaiseth)

Are you a doctor interested in specialty training that incorporates physical activity, exercise, sport and medicine?

SEM Training Programme

Although BASEM was formed in 1952, SEM was only first recognised as a medical specialty in 2005. This was closely followed by the launch of the Faculty of SEM (FSEM) in 2006 and the first cohort of SEM trainees in 2007.

The SEM training program is a four-year training program (ST3-6), which starts after completing speciality-training year 2 (ST2). Applicants wishing to apply for SEM training (starting at ST3 level) must complete two years of core medical training (CMT), acute care common stem (ACCS) or the three/four year general practice (GP) speciality-training programme. Trainees undertaking CMT or ACCS as their core training programme are required to obtain full MRCP (UK) before entry into SEM ST3. All trainees must pass the FSEM Membership exam before the end of ST5 consisting of two parts: written and practical clinical assessments1.

The SEM training programme is varied but most trainees rotate in the following specialties:

  • Emergency Medicine
  • Acute Medicine
  • Trauma and Orthopaedics
  • Musculoskeletal Medicine
  • General Practice
  • Rehabilitation Medicine
  • Public Health
  • Other: Respiratory, Cardiology, Rheumatology, Radiology
  • Military
  • Elite Sport

Trainees have exposure to SEM clinics throughout the training and spend part of ST6 working with elite athletes.

Although the FSEM is looking at ways to increase the number of training places across the UK, there are currently no training programmes in Scotland or Wales and are only in certain deaneries around the UK e.g. no posts in south or south east England.

SEM Career

SEM consultants are often portfolio doctors working in several different settings that provide flexibility and security such as: NHS consultant post, elite sports teams/athletes, private SEM/MSK clinics as well as research, education or public health activities.

Standard working hours are usually between 8am and 6pm although commitments with professional sports team can fall outside these hours. Due to the little or no on-call commitments, SEM posts do not usually include banding. Working with clubs/teams is classed as private work and can be paid or voluntary.

The shape of training final report published in 2013 has set out a new broad framework for the future of postgraduate medical education and training2. This aims to make sure doctors are trained to the highest standards whereby a doctor is less specialist and therefore broader and more adaptable to meet changing patient needs for the years to come. The shift of the FSEM Diploma Exam to the new FSEM Membership Exam in recent months is one that now allows professional recognition in Sport and Exercise Medicine to all doctors3.

The future of the speciality is to continue to incorporate SEM services within primary and secondary care, by treating MSK pain, treating and preventing chronic and non-communicable disease and doing so by increasing physical activity within the general population. Whilst funding for training posts remain uncertain, there is a need for SEM physicians to ‘bridge the gap’ between primary care and orthopaedic services. This ultimately improves the patient’s journey across the system.


Andrew Shafik, BSc (Hons), is a 4th year medical student at the University of Aberdeen with a keen interest in SEM. He has an intercalated degree in Sports & Exercise Science and is a keen footballer playing for Aberdeen University Men’s Football Club 1st XI. He is also Co-Founder & Co-President @aberdeen_sems, an Ambassador for Move.Eat.Treat and a new undergraduate representative for the Scottish branch of the FMA.

Dr Guy Evans is a newly qualified Sport and Exercise Medicine Consultant having completed SEM specialist Training in the West Midlands. He is currently the Lead Sports Physician with British Swimming and works with Bath Rugby Club. He held the role of FSEM trainee representative until completion of his Specialist Training and continues to be involved with the training and education of SEM trainees and MSc students.

Dr Ajai Seth is a Sport and Exercise Medicine Registrar and General Practitioner in the West Midlands Deanery. His sporting interests include racket sports, football, athletics and expedition medicine. He is currently Birmingham City Academy and GB para-archery doctor.


  1. Evans G. A Career In Sport and exercise medicine. Student BMJ. 2016; 24: j4336
  2. General Medical Council. (2013). Shape of Training Final Report.Available: Last accessed 5th Mar 2017.
  3. (2017). Professional Recognition in Sport and Exercise Medicine Now Available to all Doctors.Available: . Last accessed 5th Mar 2017.

Manroy Sahni (@manroysahni) coordinates the BJSM Undergraduate Perspective blog series. He also serves as Education Officer for the Undergraduate Sports and Exercise Medicine Society (USEMS) committee and Co-President of Birmingham University Sports and Exercise Medicine Society (BUSEMS).


“The Body Matters: Why Exercise Makes You Healthy and How to Stay Uninjured” via and McGill Uni- course review

20 Apr, 17 | by BJSM

 By Nash Anderson @sportmednews

As of today, I have completed the Body Matters course and I am impressed. I commenced this course in March and I want to share my reflections so others may also benefit.

I was sceptical of a free course but was convinced that I should do it. A tweet from the British Journal of Sports Medicine (BJSM) stated global experts developed it and that it discussed the benefits of exercise. I also hoped this course would enrich my knowledge by providing new and different perspectives from what I have already learnt. There is a saying “no such thing as a free lunch”, however McGill University’s “Body Matters 101” course is a free smorgasbord of useful and current knowledge.

The course contains three different units.

  • The benefits of physical activity
  • General principles on how to train and how to prevent injuries and;
  • How to recover from injury.

Content was well produced, current and of a high quality.  Topics were also informative, interesting and included animations and quizzes. It kept me engaged ensuring knowledge retention. Although at times it included some very basic information, the presenters taught me new perspectives that I had not previously considered. I particularly enjoyed the novel topics such as circus arts and treating musicians. The breadth of content was extensive providing participants with a detailed introduction to concepts ranging from the basics of anatomy, physiology and rehab to more specialty topics such as imaging and critical evaluation of medical literature.

This course made me question for the first time in my career “How does one manage a shoulder rehabilitation progression for someone who walks around on their hands or someone who hangs from a trapeze?”

The calibre of the speakers were impressive. Highlights included:

  • Steven Blair with over 500 publications discussing the benefits of exercise.
  • Robert Sallis past president of the American College of Sports Medicine (ACSM)
  • Andrew Pipe, Canadian Medical Team Physician instrumental in building world leading anti-doping programs and Canadian Commonwealth Games President
  • Leading neurologist Dr. Paul McCrory discussing concussion.
  • Margo Mountjoy, the lead author of the IOC consensus paper for Relative Energy Deficiency in Sport (RED-S) discussing this topic.

This course enriched my current knowledge by providing different perspectives. For a novice to these concepts knowledge gains could be considerable. I would recommend both health professionals and the general public complete this course. There is something for everyone. It is an inspirational health promotion resource; a huge cut above Professor YouTube and Doctor Google!

Thank you to Dr. Ian Shrier and McGill University for producing an excellent resource. I would also like to thank the BJSM dream team as always.

For more information visit:

Recommended follow-up Resources

Dr. Steven Blair:

  • Physical inactivity: the biggest public health problem of the 21st century (2009 ). BJSM. FREE Link here –;
  • BJSM Podcast. Fit vs Fat with Steven Blair. Link here –

Dr. Paul McCrory:

Dr. Margo Mountjoy


Nash Anderson is a Chiropractor in Canberra, Australia. He has a special interest in sideline care and the SEM community. He has recently returned from working as part of the Volleyball World Tour medical team in Sydney. Nash has created, an open access health and sports medicine resource for clinicians and the public. You can follow him on Twitter (@sportmednews).

Can national swimming federations be agents for health promotion?

17 Apr, 17 | by BJSM

By Clarence Perez-Diaz and Juan Carlos De la Cruz-Márquez.

In this blog we capture the essence of what we may also submit as a research paper to a journal outside the BJSM.

Background: Participation in international swimming events have increased significantly over the last 20 years. While only 46 national swimming federations (NFs) participated in the first edition of the World Swimming Championships (25 m) organised by the International Swimming Federation (FINA) in 1993,[i] this swelled to 168 by the 12th edition in Doha, Qatar, 2014.[ii]

Objectives: We investigated whether this increase has been accompanied by the implementation of health promotion programmes for the benefit of swimmers and the general population. We also addressed the question, can National Federations be agents of health promotion? To try to answer these questions, the University of Granada, Spain, conducted a study among all of FINA’s 208 member National Federations. The objectives were to determine (i) the medical resources available to the NFs, (ii) whether they had developed programmes for health promotion; and (iii) where the protection of the health of swimmers and the general population ranked among their priorities.

Methodology: We used the approach of Mountjoy and Junge (2013)[iii] who studied all 35 IFs that participated in the Olympic Games of 2014 and 2016. We circulated an online survey among all the 208 member NFs of FINA as of 2015. We followed the guidelines of the Interfederal Commission Survey on the Importance of Medicine in International Sports Federations (FIMS, 2011).[iv] All NFs were considered because NFs members of FINA must meet the same sport requirements, administrative rules and guidelines and they receive the same support for participation in international events organised by FINA. The survey was addressed to the heads of the Medical Commission of each NF and was available from October 2014 until February 2015. The questionnaire included questions about each NF’s medical structure, available health resources, health promotion programmes, their priorities, problems and needs in relation to health promotion. Results: 135 NFs responded (response rate: 65%). 42% had a physiotherapist and 36% had a doctor. Regarding competitive swimmers, only 26% of NFs had injury surveillance programmes, 19% conducted pre-participation medical examinations and 18% used return-to-play after injury programmes. The results in relation to programmes directed towards the general population were as follows: 65% to prevent drowning, 29% to include the elderly in swimming, 20% to counter obesity and 11% to prevent chronic diseases. The highest health priority of the NFs was the fight against doping (4.1 ± 0.8 out of 5), followed by the health of the elite athlete elite (3.8 ± 1.6 out of 5) and increasing the number of elite athletes (3.5 ± 1.5 out of 5), while the health of the general population is their least important health priority (2.5 ± 1.8 out of 5). Conclusions and implications: Recreational sport can promote health and contribute positively to the health of the quality of life (Eime et al., 2010). [v] However, our study suggests that only a few NFs are active agents of health promotion. We believe that for NFs, the promotion of health in the general population is not a top priority. Currently their priority is the protection of the health of their elite athletes. With the exception of drowning prevention/learn to swim programmes, other health issues related to the general population are of very low importance to NFs. In general, FINA injury surveillance/prevention programmes have not yet been adopted by the NFs. The fight against doping as NF’s highest priority is an expected result since doping is a stated top priority issue for FINA. Further, all NFs must follow the World Anti-Doping Agency (WADA) code.[vi] In response to this blog, we invite responsible physicians in national federations of other sports to share their experiences in relation to their federation’s health promotion activities for the general population. Mountjoy and Junge (2013) suggest that the ‘Football for Health’ programmes of the International Federation of Football Association (FIFA) and the FINA ‘Swimming for All’ programmes are projects that could serve as model programmes. It is unlikely however that these are the only programmes of their type. It may be safe to assume that other national sports federations have or are developing strategies to use their sports to promote healthy lifestyles among the general population. The more information that sports federations can share among each other, the greater the opportunity for the development of effective initiatives.


[i]. Adrega, P. FINA World Swimming Championships (25m), 1993-2008 – A story of success, 2010. ( accessed June 2016)

[ii].FINA Aquatics World Magazine. 12 FINA World Swimming Championships (25m). 2015; 1: 17-19.

[iii]. Mountjoy M & Junge A. The role of International Sport Federations in the protection of the athlete’s health and promotion of sport for health of the general population. Br J Sports Med 2013;47(16):1023–7.

[iv]. International Sport Medicine Federation. Survey on the Importance of Medicine in International Sports Federations, 2011. (accessed May 2016).

[v]. Eime RM, Harvey JT, Brown WJ, Payne WR. Does Sports Club Participation Contribute to Health-Related Quality of Life? Med Sci Sport Exerc 2010;42(5):1022–8.

[vi].  The World Anti-Doping Agency. The World Anti-Doping Code 2015. Montréal: WADA, 2015.


Dr. Clarence Perez Diaz completed a PhD in Health Promotion in Sports Federations (2016) and is the holder of a Degree in Sports Science (2008) from the University of Granada and a Master of Advanced Studies in Sports Administration (2009) from the EPFL, Lausanne, Switzerland. She has worked for the International Swimming Federation (FINA) and is currently working for the International Sport Medicine Federation (FIMS).

Dr. Juan Carlos de la Cruz-Marquez (MD) Graduated in Medical Sciences (cum Laude, 1982) at the University of Granada. Specialist in Sports Medicine. He completed his PhD (Medicine) in 1986. He is Tenured Lecturer of Functional Anatomy in the Department of Physical Education and Sports (University of Granada) and has been Team Doctor of several elite teams.


Exercise oncology part 1/3: Let’s get moving, exercise helps in preventing AND treating cancers!

14 Apr, 17 | by BJSM

Swiss Junior Doctors and Undergraduate Perspective on Sport and Exercise Medicine Blog Series

By Giulia Marzano and Justin Carrard, @MarzanoGiuli, @Carrard.Justin

“I am very sorry to announce you, that you suffer from a bowl cancer (…). The good news is that we are able to treat this kind of cancer with pretty good results. Treatment consists in surgery as well as chemotherapy and regular physical activity (…). The best training program includes 5 times 30 minutes of moderate intensity activity and twice a week a strength training session. I can direct you to a specialist in adapted physical activity who will help you support you to meet these targets.”

This could currently seem like science fiction to a lot of health practitioners. However, it is now widely accepted that physical activity has positive effects on preventing a lot of cancers. Growing evidence shows that exercise can also be helpful during and after cancer treatment (2).

We are pleased to launch a series of 3 blogs about exercise oncology. In this first one, we aim to review some current evidence regarding prevention and treatment of oncological diseases.

Exercise… to prevent cancer

Sedentary behaviour has shown to increase cancer risk (1,2). According to a British study, about 1% of all cancer in the UK are attributable to low physical activity level. This corresponds to 34 000 cases per year (3). The three most studied cancer types related to physical activity are breast, colon and endometrial cancers.

A meta-analysis of 31 studies show that most active women have a 12% reduced risk to develop breast cancer in comparison with least active women (4). Concerning colon cancer, meta-analyses suggest a 25% lower risk for the most active groups (5,6). Lastly, active women have apparently a 30% decreased risk to suffer from endometrial cancer (7).

A meta-analysis of 36 cohort-studies found a 17% reduced cancer mortality in the general population (i.e. people who did not have cancer at the time of the study). From those 36 studies, 5 look exclusively for colorectal cancer, 4 for pancreatic cancer, 3 for breast cancer and 22 for various cancers (8). Although there is not enough data to confirm this (1, 2, 8), other cancers (lung, pancreatic, prostate) seem to be prevented by physical activity.

Interestingly, someone who sits all day at work and exercises in the evening can be seen as sedentary. Sedentary refers to a state of muscle inactivity (like sitting or lying, with the exception of sleeping) regardless of engagement in physical activity (9). To our best knowledge there are currently no recommendations regarding the ideal daily sitting time. However, it is important to regularly break-up a sitting pattern. As studies have shown, sedentary behaviour increases risk of colon, endometrial and lung cancer (10, 11, 12).

Exercise … to help treating cancer

A recent meta-analysis of 35 studies (19 on breast cancer and 16 on colorectal cancer) concluded that the most active cancer survivors reduced their cancer mortality up to 22% regardless if they were previously active or not. Moreover, if they separated physical activity measured in the pre-diagnostic period from physical activity measured in the post-diagnostic one, the mortality reduction was greater in the post-diagnostic period (HR 0.60 vs HR 0.86). Thus, it seems that being active benefits to everyone (8).

Additionally, being active induces other somatic positive effects: preventing muscle wasting, decreasing osteoporosis risk, increase cardiovascular fitness, and seems to reduce some chemotherapy side effects (nausea and fatigue) (13).

Last but not least, exercise positively influences patients’ mood and social life by giving them greater independence based on Activities of Daily Living (ADL): improving their self-esteem, lowering anxiety and depression risk (13).

With their review, Browall et al. show physical activity as an adjuvant treatment for women affected by breast cancer. After the improvement of physical fitness, women feel content and empowered. They have the impression to have control over the disease. Given that they are not treated as patients, taking part in exercise programs also is a helpful tool for patients to gain a sense of normality, away from the medical sphere. Furthermore, it is also a chance for an opportunity to meet other people who suffer from the same disease and talk openly about it (13).

How does it work?

  • Several mechanisms are described in the literature. They are listed in Table 1, which is reproduced from Thomas et. Al’s BJSM publication: Exercise-induced biochemical changes and their potential influence on cancer: a scientific review (14).
  • Exercise has 4 mains effects:
  • 1) Reducing hormones which promote cell growth and increasing mechanisms which protect the cell
  • 2) Boosting the immune system
  • 3) Reducing inflammation
  • 4) Boosting antioxidants’ pathways

Others mechanisms include:

Increasing bowel movements

Exercise accelerates bowl transit and thus oncogenic substances pass through the bowel more quickly.

Preventing obesity

If obesity is a well-known cancer risk factor, exercise is much more than a weight control tool (1,2). To date, being obese and active is healthier than being normal weight and inactive; this is why fitness is more important than fatness (15).

Preventing metastasis

Regmi et al. studied the effect of physical activity on circulating tumour cells, which cause distal metastasis. By means of a microfluidic circulatory system, they simulated the high levels of shear stress that can be produced during exercise in the femoral artery. Hemodydamic shear stress can destroy circulating tumour cells in the blood stream. The researchers observed that the higher the stress, the larger the number of destroyed cells. Interestingly, this mechanism affects way more tumour cells (breast, lung, ovarian) than blood cells.They also observed the efficacy of shear stress on drug resistant breast cancer cells (16).

In the next blog we will speak about exercise oncology with an oncologist specialized in breast cancer.


Giulia Marzano is a second year medical student at the University of Basel (Switzerland) with a great passion for sport. She is a member of Students & Junior Doctors SGSM/SSMS, she practices athletics and is specialized in middle-distance.



Justin Carrard is a first year internal medicine resident based in Biel/Bienne (Switzerland). He coordinates the BJSM Swiss Junior Doctors and Undergraduate Perspective Blog Series and leads the Students & Junior Doctors SGSM/SSMS movement. Justin aims to raise SEM awareness among medical students and modern solutions it provides to big public health issues like non-communicable diseases. As an ex-competitive swimmer, he has a keen interest for endurance sports and regularly practices them with passion.


Twitter: @Carrard.Justin

If you would like to contribute to the “Swiss Junior Doctors and Undergraduate Perspective on Sport and Exercice Medicine” Blog Series please email for further information.


  1. IARC, Weight Control and Physical Activity. IARC Handbooks of Cancer Prevention, ed. H. Vainio and F. Bianchini. Vol. 6. 2002, Lyon: IARC.
  2. WCRF and AICR. Food, nutrition, physical activity and the prevention of cancer: A global perspective. 2007, Washington: American Institute for Cancer Research.
  3. Parkin, M., et al, The fraction of cancer attributable to lifestyle and environmental factors in the UK in 2010. BJC 2011. 105(Supp 2): S38-S41.
  4. Wu, Y., et al. Physical activity and risk of breast cancer: a meta-analysis of prospective studies. Breast Cancer Res, 2013. 137(3): p. 869-82.
  5. Wolin, K., et al. Physical activity and colon cancer prevention: a meta-analysis. Br J Cancer, 2009. 100(4): p. 611-6.
  6. Robsahm, T.E., et al. Body mass index, physical activity, and colorectal cancer by anatomical subsites: a systematic review and meta-analysis of cohort studies. Eur J Cancer Prev, 2013.
  7. Moore, S.C, et al. Physical activity, sedentary behaviours, and the prevention of endometrial cancer. Br J Cancer 2010. 103 (7): 933-8.
  8. Li T, Wei S, Shi Y, et al. The dose–response effect of physical activity on cancer mortality: findings from 71 prospective cohort studies. Br J Sports Med 2016;50:339–345.
  9. Hamilton MT, Healy GN, Dunstan DW, Zderic TW, Owen N. Too Little Exercise and Too Much Sitting: Inactivity Physiology and the Need for New Recommendations on Sedentary Behavior. Current cardiovascular risk reports. 2008;2(4):292-298.
  10. Cong, Y. J. et al. Association of sedentary behaviour with colon and rectal cancer: a meta-analysis of observational studies. British Journal of Cancer, 2014. 110, p. 817–26.
  11. Schmid, D. & Leitzmann, M. F. Television viewing and time spent sedentary in relation to cancer risk: a meta-analysis. Journal of the National Cancer Institute, 2014. 106, p. 1–19.
  12. Shen, D. et al. Sedentary behavior and incident cancer: a meta-analysis of prospective studies. PloS ONE 9, 2014.
  13. Browall M, Mijwel S, Rundqvist H, Wengström Y. Physical Activity During and After Adjuvant Treatment for Breast Cancer: An Integrative Review of Women’s Experiences. Integrative cancer therapies 2016; DOI: 10.1177/1534735416683807
  14. Thomas RJ, Kenfield SA, Jimenez A. Exercise-induced biochemical changes and their potential influence on cancer: a scientific review Br J Sports Med Published Online First:19.12.2016 doi:10.1136/ bjsports-2016-096343
  15. Barry, Vaughn W. et al. Fitness vs. Fatness on All-Cause Mortality: A Meta-Analysis Progress in Cardiovascular Diseases , Volume 56 , Issue 4 , 382 – 390
  16. Regmi S, Fu A, Qian Luo K. High Shear Stresses under Exercise Condition Destroy Circulating Tumor Cells in a Microfluidic System. Scientific Reports 2017; 7:39975

Young athletes’ optimal health: Part 3 Consequences of Relative Energy Deficiency in sports

12 Apr, 17 | by BJSM

Part-3 of the blog mini-series on RED-S

By Dr Nicky Keay

In my previous blogs, I  described the adverse effects of Relative Energy Deficiency in sports (RED-S) in both female and male athletes- 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.

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 .


Optimal Health: including female athletes! Part 1 Bones British Journal of Sport Medicine

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

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

Using strength and conditioning in Physiotherapy

10 Apr, 17 | by BJSM

Association of Chartered Physiotherapists in Sport and Exercise Medicine blog series @PhysiosinSport

By Emily Drakes

My interest in strength and conditioning started after watching an evening lecture from Raphael Brandon. I was intrigued by the theory behind exercise prescription. Also, physiotherapy seems to be moving more and more towards exercise as the mainstay of treatment, as seen in the recent NICE guidelines for low back pain1, so this seemed like the right path to follow.

For those of you lucky enough to work with S&C coaches you will have them on hand to guide exercise prescription. However for most of us working in physiotherapy teams, having more of an S&C background can offer valuable insight into the best way to strengthen and prepare a patient for their activities whether that is a seasoned marathon runner or a stay at home parent with children to carry.

It has been refreshing in learning about S&C to put injuries to one side and focus on the most effective way to plan an exercise programme. Many physiotherapist’s are preoccupied with making an exercise look like the movement or sport they are trying to rehabilitate their patient to i.e. giving a patient who plays football a ball to use in an exercise. However when if you break down the amount of time a footballer spends with a ball over 90mins it amounts to 90s2! The rest of the time is spent running, changing direction and jostling for the ball. Obviously a lot of the time a footballer is training involves a ball but unless you break it down in to the components of a skill you have no overload. This is what S&C essentially comes down to, ensuring specific adaptations to imposed demands. We need to understand the way a force is developed in the sport/activity we are interested in and in the exercise we are choosing to prescribe to get the desired outcome.

There are some general principles that I now use daily that are key to exercise prescription. Firstly a needs analysis, which is something we all do to some extent but it formalises the process of deciding where a person is dysfunctional for the activity they are struggling with. The diagram below outlines this:

Once you’ve specified the activity and what one would need to perform that successfully/pain free then you would look at the gap between the person in front of you vs. the ideal attributes they need. Once you know this, targeting their exercise should be much easier.

The needs analysis and the selection of exercises both incorporate the principle of dynamic correspondence described by Siff and Verkoshansky3. This is a guide on the different aspects of the activity to consider and how the exercise you are choosing will correlate to it.

Unless you are doing the exercise itself i.e. kicking a ball you are not going to be 100% specific, however as discussed above in order to overload the components you need to break it down into parts. We will use the example of squatting and sprint ability in football:







There are 5 key aspects to consider:

  • Amplitude and direction of movement

This is the most familiar principle in that we are looking at the direction of force relative to the performed movement.

The squat does not look like a sprint however the lower limb movement of the hip, knee and ankle triple extension on the ascent on the squat is similar.

The transmission of force from a flexed position to full extension in the squat is similar to the explosive action a footballer will need to perform when starting to sprint.

  • Rate and time of peak force production

The peak rate of force production of a footballer sprinting is within 100 – 200 ms4 and for a squat is 300ms5 therefore it may not be as fast as it needs to be, however you may choose to use a lighter load at performed at maximum speed to improve this. It has been seen that 40-50% of 1RM achieves peak velocity and power in a squat.

  • Dynamics of effort (whether a concentric max effort or eccentric slow effort is desired for each lift)

The training stimulus and effort needs to be greater than the sporting skill or activity we are training for, which in a heavy weighted squat certainly would be for sprinting over 30m. Peak power for the concentric phase of a squat is 4000W5 and for sprinting it’s 1200W4 in the propulsion phase.

  • Accentuated region of force development (Joint angle specificity)

The squat will yield a greater range of movement than the sprinting motion. This means that you are overloading the skill by creating greater strength in a larger range of movement. Based on research football players accelerating the knee angle averages at 89 degrees6, correlates well with a parallel squat (90 degrees).

  • Regime of muscular work (Type of muscle action)

For a squat the initial phase is eccentric action of the quadriceps and glutes then concentric extension on the ascent of the glutes, quadriceps and hamstrings. In a sprint the initial movement to overcome inertia is concentric which corresponds with the ascent phase of the squat. The top speed running of a footballer will involve the glutes, hamstrings and quadriceps moving from concentric to eccentric muscle action, as does the squat7.

The greater power needed through the triple extension phase of the squat achieves greater motor recruitment which is thought to be one of the reasons a squat correlates so well with sprint speed in soccer players as the athlete is able to use more of the motor units to generate max speed8.

This was a brief illustration of how strength and conditioning principles can be used to look deeper into the activity or sport you are looking to achieve with a patient. It has certainly highlighted to me over my degree so far that there is a lot more to train than what a movement looks like which can help you prepare your patient or athlete in a more well rounded way for their sport.


  1. Bradley, Sheldon, Wooster, Olsen, Boanas & Krustrup (2009) High-intensity running in English FA Premier League soccer matches, Journal of Sports Sciences, 27:2, 159-168
  2. Siff,MC. (2003) Supertraining(6thEd).Denver,CO:Supertraining Institute
  3. Plisk,SS.Speed,agility,andspeed-endurancedevelopment. In: Baechle, TR, and Earle, RW (Eds.), Essentials of Strength Training and Conditioning (3rd Edition). Champaign IL: Human Kinetics; 457-485, 2008.
  4. Nummela, Rusko and Mero (1994). EMG activities and ground reaction forces during fatigued and non fatigued sprinting. Medicine and science in sports and exercise 22(2) 605-609
  5. Zink, Perry, Robertson, Roach and Signorile (2006). Peak power, Ground Reaction Forces and Velocity During the Squat Exercise Performed at Different Loads. Journal of Strength and Conditioning Research, 20(3), 658–664
  6. Spinks, Murphy, Spinks and Lockie (2007) The Effects of Resisted Sprint Training and Acceleration Performance and Kinematics in Soccer, Rugby Union and Australian Football Players Journal of Strength and Conditioning Research 21(1), 77-85
  7. Wisloff,U,Castagna,C,Helgerud,J,Jones,R,andHoff, J. Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players. British Journal of Sports Medicine 38(3): 285-288, 2004.
  8. Markovic, Jukic, Milanovic and Metikos (2007) Effects of Sprint and Plyometric Trianing on Muscle Function and Athletic Performance Journal of Strength and Conditioning Research 21(2), 543-549.


Emily Drakes, ACPSEM Physio

Are elite athletes at higher risk of developing cardiovascular abnormalities than the average citizen?

6 Apr, 17 | by BJSM

By Javier S. Morales (MSc), Pedro L. Valenzuela (MSc), and Adrián Castillo García (MSc): @Fissac_es

High performance sport is a focal point for the media, and sadly, cases of sudden death in elite athletes appear in the news with relative frequency. These news added to findings such as those of Pellicia et al. (2016), who reported an unexpected and not negligible prevalence of cardiovascular (CV) abnormalities and pathological conditions among Olympic athletes (Pelliccia et al., 2016), have put exercise on the spotlight, with growing concern about the possible negative effects that regular strenuous exercise can provoke.

In light of the existing debate about the increased health risks of elite athletes, we consider that this information could lead people to misconceive the high volumes of exercise that these athletes perform during their sportive life as the cause of the aforementioned CV abnormalities. However, taking into account that nowadays sedentarism and its associated diseases are one of the greatest public health issues, we must avoid people from thinking of strenuous exercise per se as a source of increased morbidity or mortality.

Performing moderate physical activity has well-documented beneficial effects on CV morbidity, but there is controversy surrounding the effects of larger doses of physical activity (Eijsvogels, Fernandez, & Thompson, 2016). Concerning the CV maladaptation to strenuous exercise, Sanchis-Gomar et al. (2016) found in former elite and amateur athletes aged 40-70 years old that, although they presented an overall pattern of cardiac remodeling in comparison with control non-athletes participants (e.g. larger left and right ventricles and left auricle cavities), these changes were benign, with no differences in cardiac biomarkers (Sanchis-Gomar et al., 2016). Similarly, Bohm et al also reported these non-pathological morphological adaptations in elite master endurance athletes with a training history of 29±8 years, with no differences between these athletes and the control group neither for left or right ventricle volumes nor for cardiac biomarkers (Bohm et al., 2016). These results confirm that although the possibility of exercise-induced cardiac remodeling in elite athletes is high, these adaptations are very likely to be benign.

In fact, there is a large body of research supporting that the population that perform the highest levels of physical activity (i.e. elite athletes) seem to present a lower risk of CV diseases and mortality. Specifically, a meta-analysis including 42087 elite athletes reported a 27% lower risk of mortality associated to CV diseases in comparison with the general population (Garatachea et al., 2014). Furthermore, an epidemiological study that analyzed 15174 Olympic medalists found that these subjects lived a mean of 2.8 years more than the average population, independently of the country or the type of sport performed (Clarke et al., 2012).

On the other hand, it has been described a higher prevalence of sudden death in young athletes than in their non-athletes counterparts (Corrado, Basso, Rizzoli, Schiavon, & Thiene, 2003). However, it is important to highlight that physical exercise was not per se the cause of this enhanced mortality, but it triggered the event in those subjects who were already affected by an undiagnosed CV disease.

Therefore, very large doses of physical exercise such as those performed by elite athletes seem not to increase the prevalence of CV diseases during youth or even in later years, as the CV and mortality risk of elite athletes is the same or even lower than that of the average citizen. The dramatic occurrence of cardiac events in young athletes as well as the interesting results reported by Pelliccia et al. (2016) must raise consciousness about the necessity of an appropriate medical screening in the sportive context; strenuous physical exercise can trigger cardiac arrest in those subjects with a previous undiagnosed CV disease. However, they should not sharpen the discussion on the suitability of performing high-performance physical exercise from early ages.


This post has been written by the FISSAC team (@Fissac_es):

Javier S. Morales is a researcher of the European University (Madrid). He also collaborates as a researcher at the Hospital Niño Jesús (Madrid) in childhood cancer and physical exercise.

Pedro L. Valenzuela is a pre-doctoral researcher in the Phisiology Unit of the University of Alcalá. He also serves as external collaborator in the Sports Medicine Centre of the Spanish Agency for Health Protection in Sport (AEPSAD).

Adrián Castillo García is a researcher at the Institute of Biomedical Research of Barcelona, research center that belongs to the Spanish National Research Council.”


Bohm, P., Schneider, G., Linneweber, L., Rentzsch, A., Krämer, N., Abdul-Khaliq, H., . . . Scharhag, J. (2016). Right and Left Ventricular Function and Mass in Male Elite Master Athletes: A Controlled Contrast-Enhanced Cardiovascular Magnetic Resonance Study. Circulation, 133(20), 1927-1935. doi:10.1161/CIRCULATIONAHA.115.020975

Clarke, P. M., Walter, S. J., Hayen, A., Mallon, W. J., Heijmans, J., & Studdert, D. M. (2012). Survival of the fittest: retrospective cohort study of the longevity of Olympic medallists in the modern era. BMJ, 345, e8308.

Corrado, D., Basso, C., Rizzoli, G., Schiavon, M., & Thiene, G. (2003). Does sports activity enhance the risk of sudden death in adolescents and young adults? J Am Coll Cardiol, 42(11), 1959-1963.

Eijsvogels, T. M., Fernandez, A. B., & Thompson, P. D. (2016). Are There Deleterious Cardiac Effects of Acute and Chronic Endurance Exercise? Physiol Rev, 96(1), 99-125. doi:10.1152/physrev.00029.2014

Garatachea, N., Santos-Lozano, A., Sanchis-Gomar, F., Fiuza-Luces, C., Pareja-Galeano, H., Emanuele, E., & Lucia, A. (2014). Elite athletes live longer than the general population: a meta-analysis. Mayo Clin Proc, 89(9), 1195-1200. doi:10.1016/j.mayocp.2014.06.004

Pelliccia, A., Adami, P. E., Quattrini, F., Squeo, M. R., Caselli, S., Verdile, L., . . . Spataro, A. (2016). Are Olympic athletes free from cardiovascular diseases? Systematic investigation in 2352 participants from Athens 2004 to Sochi 2014. Br J Sports Med. doi:10.1136/bjsports-2016-096961

Sanchis-Gomar, F., López-Ramón, M., Alis, R., Garatachea, N., Pareja-Galeano, H., Santos-Lozano, A., . . . Lucia, A. (2016). No evidence of adverse cardiac remodeling in former elite endurance athletes. Int J Cardiol, 222, 171-177. doi:10.1016/j.ijcard.2016.07.197


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

4 Apr, 17 | by BJSM

Part-2 of the blog mini-series on RED-S

By Dr Nicky Keay

If you are a male athlete, or work with male athletes, and think that Relative Energy Deficiency in sport (RED-S) is just a problem for females, think again.

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.


Optimal health: including female athletes! Part 1 Bones 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 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.

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