Periodisation – Dr Nicky Keay

Internal Biological Clocks and Sport Performance

5 October 2017

A Nobel Prize was awarded this week to researchers who uncovered the molecular mechanisms controlling circadian rhythm: our internal biological clock.

PastedGraphic-2 — Circadian Hormone Release

These mechanisms rely on negative feedback loops found in many biological systems where periodicity of gene expression is key, such as the Endocrine system. Internal biological clocks allow for anticipation of the requirements from body systems at different times of the day and the ability to adapt to changes in external lifestyle factors. What is the clinical significance of biochronometers?

The importance of integration of lifestyle factors, such as timing of eating, activity and sleep with our internal biological clocks is revealed in situations of circadian misalignment that lead to suboptimal health and disease states in the longer term.

Consideration of our biochronometers is especially important for athletes in order to synchronise periodised training, nutrition and recovery and thus optimise health and sports performance.

Athletic Performance Performance in a cycle time trial was found to be better in the evening, rather than the morning, proposed to be due to a more favourable endogenous hormonal and metabolic internal milieu. Certainly there were some disgruntled swimmers at an international event, when the usual pattern of morning heats and evenings finals was switched, to accommodate television viewing spectators.

Female athletes: menstrual cycle/training season Women have an extra layer of endogenous biological periodicity in the form of the menstrual cycle controlled by temporal changes of hormone release in the hypothamalmus-pituitary-ovarian Endocrine axis. Changes in external factors of training load, nutrition and recovery are detected by the neuroendocrine gatekeeper, the hypothalamus, which produces an appropriate change in frequency and amplitude of GnRH (gonadotrophin releasing hormone), which in turn impacts the pulsatility of LH (lutenising hormone) release from the pituitary and hence the phases of the menstrual cycle, in particular ovulation. Even short term reduction of energy availability in eumenorrhoeic female athletes can inhibit LH pulsatility frequency and release of other hormones such as IGF1. Disrupted release of sex steroids and IGF1 has a negative effect on bone turnover: increased resorption and decreased formation. Active females have been found more susceptible to reduction in energy availability impacting bone metabolism than their male counterparts.

Another consequence of the phasic nature of the menstrual cycle relating to external factors such as exercise, is that injury risk could be linked to changes in the expression of receptors for for sex steroids oestrogen and progesterone in skeletal muscle. Certainly during pregnancy and the post partum period, relaxin hormone increases the laxity of soft tissues, such as ligaments, and hence maintenance stretching, rather than seeking to increase flexibility, is recommended to prevent injury, .

In order to produce desired temporal adaptive changes in response to exercise training, signalling pathways mediated by reactive oxidative species and inflammatory markers are stimulated in the short term, with supportive Endocrine interactions in the longer term. However, an over-response can impair adaptive changes and impact other biological systems such as the immune system. This maladaptive response could occur as a result of non-integrated periodisation of training, nutrition and recovery in athletes and, in the case of female athletes, oral contraceptive pill use has been implicated, as this effectively imposes a medical menopause, preventing the phasic release of endogenous hormones.

Considering a longer time scale, such as a training season, female athletes were found to have a more significant fall ferritin during than male athletes. Low normal iron does not necessarily correlate to iron deficiency anaemia, but low levels in athletes can impact bone health. Supplementation with vitamin C to improve absorption may help, although iron overload can have deleterious effects. As training intensity increases as the season progresses, six monthly haematological reviews for female athletes were recommended in this study.

Changes in set point feedback Feedback control of the Endocrine system, for example the hypothalamic-pituitary-thyroid axis is dynamic: both anticipatory and adaptive, depending on internal and external inputs. However, presentation of a prolonged stimulus can result in maladaptation in the longer term. For example, disruption of signalling pathways leading to hyperinsulinaemia results in insulin resistance, which represents the underlying pathophysiological mechanism of obesity and the metabolic syndrome. In other words a situation of tachyphylaxis, where prolonged, repeated stimulus over time results in insensitivity to the original stimulus. This also applies to the nature of exercise training over a training season and diets that exclude a major food type: temporal variety is key.

Lifespan (prematurity, ageing) Changes during the lifespan represent an important biochronometer. Premature and small-for-dates babies are at risk of long term metabolic and Endocrine dysfunction, potentially due to intrauterine reprogramming of the hypothalamic-pituitary axis. At the other end of the biological time scale, with advancing age, DNA methylation and changes in epigenetic expression occur. It has been suggested that this age related methylation drift could be delayed with calorie restriction. Melatonin, a key player in intrinsic biological time keeping has been proposed to attenuate bone resorption by reducing relative oxidative stress. This would potentially explain why shift workers with disrupted sleep patterns are reported to be at risk not only of metabolic dysfunction, but also impaired bone health. Disrupted sleep patterns are a concern for athletes, especially those whose training and competition schedule involve frequent international travel across time zones.

In summary, respecting your internal biological clocks and integrating your lifestyle and your training, nutrition and recovery with these intrinsic pacemakers in mind will optimise health and performance.

For further discussion BASEM annual conference 22/3/18: Health, Hormones and Human Performance

Presentations

References

The Nobel Prize in Physiology or Medicine 2017

Circadian clock control of endocrine factors Nat. Rev. Endocrinol

Temporal considerations in Endocrine/Metabolic interactions Part 1 Dr N. Keay, British Journal of Sports Medicine 2017

Temporal considerations in Endocrine/Metabolic interactions Part 2 Dr N. Keay, British Journal of Sports Medicine 2017

Athletic Fatigue: Part 2 Dr N. Keay 2017

Effect of Time of Day on Performance, Hormonal and Metabolic Response during a 1000-M Cycling Time Trial Plos One 2017

Optimal Health: For All Athletes! Part 4 – Mechanisms Dr N. Keay, British Association of Sport and Exercise Medicine 2017

Effects of reduced energy availability on bone metabolism in women and men Bone 2017

Expression of sex steroid hormone receptors in human skeletal muscle during the menstrual cycle Acta Physiol (Oxf). 2017

Endocrine system: balance and interplay in response to exercise training

Kynurenic acid is reduced in females and oral contraceptive users: Implications for depression Science Direct 2017

Oxidative Stress in Female Athletes Using Combined Oral Contraceptives Sports Medicine

Iron monitoring of male and female rugby sevens players over an international season J Sports Med Phys Fitness. 2017

Thyroid Allostasis–Adaptive Responses of Thyrotropic Feedback Control to Conditions of Strain, Stress, and Developmental Programming Frontiers in Endocrinology 2017

Stress- and allostasis-induced brain plasticity Annu Rev Med

Optimising Health and Athletic Performance Dr N. Keay 2017

Long-term metabolic risk among children born premature or small for gestational age Nature Reviews Endocrinology 2017

Caloric restriction delays age-related methylation drift Nature Communications 2017

Melatonin at pharmacological concentrations suppresses osteoclastogenesis via the attenuation of intracellular ROS Osteoporosis International 2017

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

Optimising Health and Athletic Performance

20 September 2017

FactorsWordCloud4

In order to improve sports performance, athletes periodise their training, nutrition and recovery within the context of a training season. For those not in exercise training, these controllable lifestyle factors correspond to exercise, diet and sleep, which require modification during the lifespan. In old money, this was called preventative medicine. Taking this a step further, rather than preventing disease, this proactive, personalised approach optimises health. Health should be a positive combination of physical, mental and social well being, not simply an absence of illness.

Failure to balance these lifestyle factors in an integrated fashion leads to negative outcomes. An athlete may experience maladaptation, rather than the desired adaptations to exercise training. For non-athletes an adverse combination of lifestyle factors can lead to suboptimal health and a predisposition to developing chronic disease.

What are the fundamental pathophysiological mechanisms involved in the aetiology of the clinical spectrum of suboptimal health, suboptimal sports performance and chronic disease?

Inflammation A degree of systemic inflammation and oxidative stress induced by exercise training is required to drive desired adaptations to support improved sport performance. However, prolonged, elevated levels of inflammation have adverse effects on health and underpin many chronic disease states. For example, inflammation is a contributing pathophysiological factor in the development of atherosclerosis and atherothrombosis in cardiovascular disease. What drives this over-response of the inflammatory process? Any combination of adverse lifestyle factors. Adipose tissue has an Endocrine function, releasing a subgroup of cytokines: adipokines which have peripheral and central signalling roles in energy homeostasis and inflammation. In a study of Belgian children, pro-inflammatory energy related biomarkers (high leptin and low adiponectin) were associated with decreased heart rate variability and hence in the long term increased risk of cardiovascular disease. For those with a pre-existing chronic inflammatory condition, response to treatment can be optimised with personalised lifestyle interventions.

Metabolism Non-integrated lifestyle factors can disrupt signalling pathways involved in glucose regulation, which can result in hyperinsulinaeamia and insulin resistance. This is the underlying pathological process in the aetiology of metabolic syndrome and metabolic inflexibility. Non-pharmacological interventions such as exercise and nutrition, synchronised with endogenous circadian rhythms, can improve these signalling pathways associated with insulin sensitivity at the mitochondrial level.

Intriguingly, evidence is emerging of the interaction between osteocalcin and insulin, in other words an Endocrine feedback mechanism linking bone and metabolic health. This is reflected clinically with increased fracture risk found amongst type 2 diabetics (T2DM) with longer duration and higher HbA1C.

Hormone imbalance The hypothalamus is the neuroendocrine gatekeeper of the Endocrine system. Internal feedback and external stimuli are integrated by the hypothalamus to produce an appropriate Endocrine response from the pituitary gland. The pathogenesis of metabolic syndrome involves disruption to the neuroendocrine control of energy homeostasis with resistance to hormones secreted from adipose tissue (leptin) and the stomach (ghrelin). Further evidence for the important network effects between the Endocrine and metabolic systems comes from polycystic ovarian syndrome (PCOS). Although women with this condition typically present to the Endocrine clinic, the underlying aetiology is metabolic dysfunction with insulin resistance disrupting the hypothamic-pituitary-ovarian axis. The same pathophysiology of disrupted metabolic signalling adversely impacting the hypothalamic-pituitary-gonadal axis also applies to males.

In athletes, the exact same signalling pathways and neuroendocrine systems are involved in the development of relative energy deficiency in sports (RED-S) where the underlying aetiology is imbalance in the periodisation of training load, nutrition and recovery.

Gastrointestinal tract In addition to malabsorption issues such as coeliac disease and non-gluten wheat sensitivity, there is emerging evidence that the composition and diversity of the gut microbiota plays a significant role in health. The microbiome of professional athletes differs from sedentary people, especially at a functional metabolic level. Conversely, an adverse gut microbiome is implicated in the pathogenesis of metabolic dysfunction such as obesity and T2DM, via modulation of enteroendocrine hormones regulating appetite centrally and insulin secretion peripherally.

Circadian disregulation As previously discussed, it is not just a question of what but WHEN you eat, sleep and exercise. If there is conflict in the timing of these lifestyle activities with internal biological clocks, then this can disrupt metabolic and endocrine signally. For example, in children curtailed sleep can impact glucose control and insulin sensitivity, predisposing to risk of developing T2DM. Eating too close to the onset of melatonin release in the evening can cause adverse body composition, irrespective of what you eat and activity levels. In those with pre-existing metabolic dysfunction, such as PCOS, timing of meals has an effect on insulin levels and hence reproductive Endocrine function. The immune system displays circadian rhythmicity which integrated with external cues (for example when we eat/exercise/sleep) optimises our immune response. For athletes competing in high intensity races, this may be more favourable in terms of Endocrine and metabolic status in the evening.

Psychology Psychological stress impacts the key pathophysiological mechanisms outlined above: metabolic signalling, inflammation and neuroendocrine regulation, which contribute to Endocrine and metabolic dysfunction. Fortunately stress is a modifiable lifestyle risk factor. In the case of functional hypothalamic amenorrhoea (where nutrition/exercise/sleep are balanced), psychological intervention can reverse this situation.

Conclusion Putting this all together, if the modifiable lifestyle factors of exercise, nutrition, sleep are optimised in terms of composition and timing, this improves metabolic and Endocrine signalling pathways, including neuroendocrine regulation. Preventative Medicine going beyond preventing disease; it optimises health.

BASEM annual conference 22/3/18: Health, Hormones and Human Performance

Presentations

References

Athletic Fatigue: Part 2 Dr N. Keay

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

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

Saturated fat does not clog the arteries: coronary heart disease is a chronic inflammatory condition, the risk of which can be effectively reduced from healthy lifestyle interventions British Journal of Sports Medicine 2017

Longitudinal Associations of Leptin and Adiponectin with Heart Rate Variability in Children Frontiers in Physiology 2017

A Proposal for a Study on Treatment Selection and Lifestyle Recommendations in Chronic Inflammatory Diseases: A Danish Multidisciplinary Collaboration on Prognostic Factors and Personalised Medicine Nutrients 2017

Assessment of Metabolic Flexibility by Means of Measuring Blood Lactate, Fat, and Carbohydrate Oxidation Responses to Exercise in Professional Endurance Athletes and Less-Fit Individuals Sports Medicine 2017

Skeletal muscle mitochondria as a target to prevent or treat type 2 diabetes mellitus Nature Reviews Endocrinology

Insulin and osteocalcin: further evidence for a mutual cross-talk Endocrine 2017

HbA1c levels, diabetes duration linked to fracture risk Endocrine Today 2017

The cellular and molecular bases of leptin and ghrelin resistance in obesity Nature Reviews Endocrinology 2017

Metabolic and Endocrine System Networks Dr N. Keay

Adiponectin and resistin: potential metabolic signals affecting hypothalamo-pituitary gonadal axis in females and males of different species Reproduction 2017

Optimal Health: For All Athletes! Part 4 – Mechanisms Dr N. Keay, British Association of Sport and Exercise Medicine 2017

Ubiquitous Microbiome: impact on health, sport performance and disease Dr N. Keay

The microbiome of professional athletes differs from that of more sedentary subjects in composition and particularly at the functional metabolic level Gut. BMJ

Interplay between gut microbiota, its metabolites and human metabolism: Dissecting cause from consequence Trends in Food Science & Technology 2016

Temporal considerations in Endocrine/Metabolic interactions Part 1 Dr N. Keay, British Journal of Sports Medicine 2017

Temporal considerations in Endocrine/Metabolic interactions Part 2 Dr N. Keay, British Journal of Sports Medicine 2017

Sleep Duration and Risk of Type 2 Diabetes Paediatrics 2017

Later circadian timing of food intake is associated with increased body fat Am J Clin Nutr. 2017

Effects of caloric intake timing on insulin resistance and hyperandrogenism in lean women with polycystic ovary syndrome Clin Sci (London)

Immunity around the clock Science

Effect of Time of Day on Performance, Hormonal and Metabolic Response during a 1000-M Cycling Time Trial PLOS

Type 2 diabetes mellitus and psychological stress — a modifiable risk factor Nature Reviews Endocrinology 2017

Recovery of ovarian activity in women with functional hypothalamic amenorrhea who were treated with cognitive behaviour therapy Fertil Steril

Athletic Fatigue: Part 2

3 September 2017

A degree of athletic fatigue following a training session, as described in part 1, is required to set in motion mechanisms to drive beneficial adaptations to exercise. At what point does this process of functional over-reaching tip into non-functional over-reaching denoted by failure to improve sports performance? Or further still along the spectrum and time scale, the chronic situation of overtraining and decrease in performance? Is this a matter of time scale, or degree, or both?

: Integrated Periodisation of Training Load, Nutrition and Recovery keeps an individual on the green plateau, avoiding descent into the red zone, due to an excess or deficiency

Determining the tipping point between these fatigue situations is important for health and performance. A first step is always to exclude underlying organic disease states, be these of Endocrine, systemic inflammatory or infective aetiologies. Thereafter the crucial step is to assess whether the periodisation of training, nutrition and recovery are integrated over a training block and in the longer term over a training season.

What about the application of Endocrine markers to monitor training load? Although the recent studies described below are more applicable to research scenarios, they give some interesting insights into the interactive networks effects of the Endocrine system and the multifactorial nature of fatigue amongst individual athletes.

In the short term, during a 2 day rowing competition, increases in wakening salivary cortisol were noted followed by return towards baseline in subsequent 2 day recovery. Despite individual variability with salivary cortisol measurement, this does at least offer a noninvasive way to adjust training loads around competition time for elite athletes.

Over an 11 day stimulated training camp and recovery during the sport specific preparatory phase of the training season, blood metabolic and Endocrine markers were measured. In the case of an endurance based training camp in cyclists, a significant increase in urea (due to protein breakdown associated with high energy demand training) and decrease in insulin-like growth factor 1 (IGF1) from baseline were noted. Whereas for the strength-based athletes for ball sports, an increase in creatine kinase (CK) was seen, as a result of muscle damage. This study demonstrates how different markers of fatigue are specific to sport discipline and mode of training. Large inter-individual variability existed between the degree of change in markers and degree of fatigue.

In the longer term, for the case of overtraining syndrome potential Endocrine markers have been reviewed. Whilst basal levels of most measured hormones remained stable, a blunted submaximal exercise response of growth hormone (GH), prolactin and ACTH could be indicative of developing overtraining syndrome. Whilst this review is interesting, dynamic testing is not a practical approach and these findings are not specific to over training. Rather this blunted dynamic exercise response would indicate relative suppression of the neuroendocrine hypothalamic-pituitary axis which could potentially involve other stressors such as inadequate sleep or poor nutrition. Although basal levels may lie “within the normal range”, if both pituitary derived stimulating hormone and end endocrine gland hormone concentrations fall in the lower end of the normal ranges (eg low end of range TSH and T4) this is consistent with mild hypothalamic suppression observed over the range of training and fatigue conditions (functional/non-functional and overtraining) and/or Relative Energy Deficiency in Sports (RED-S).

Although the studies above are of research interest, non invasive monitoring, specific to an athlete is more practical for monitoring the effects of training. Several useful easily measurable metrics can give clues: resting heart rate, heart rate variability, power output. Tools on Strava and Training Peaks provide practical insights in monitoring training effectiveness via these metrics. A range of mobile apps makes it ever easier to augment a personal training log to include these training metrics, along with feel, sleep and nutrition. Such a log provides feedback on health and fitness for the individual athlete, in order to personalise training plans. Certainly adding the results from any standard basal blood tests will also help add to the picture, along the lines of building a longitudinal personal biological passport. After all, “normal ranges” are based on the general population, of which top level athletes may represent a subgroup. The more personalised the metics recorded over a long time scale, the more sensitive and useful the process to guide improvement in sport performance.

Context is key when considering athletic fatigue: temporal considerations and individual variation. Certainly the interactive network effects of the Endocrine system are important in determining the degree of adaptation to exercise and therefore sports performance. However the Endocrine system acts in conjunction with many other systems (metabolic, immune and inflammatory), in determining the effectiveness of training in improving sports performance. So it is not surprising that one metric or marker in isolation is not predictive of fatigue status in individual athletes.

For more discussion on Health, Hormones and Human Performance come to the British Association of Sport and Exercise Medicine annual conference

Presentations

References

Athletic Fatigue: Part 1

Endocrine system: balance and interplay in response to exercise training

Temporal considerations in Endocrine/Metabolic interactions Part 1

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

Sport Performance and RED-S, insights from recent Annual Sport and Exercise Medicine and Innovations in Sport and Exercise Nutrition Conferences Dr N Keay, British Journal of Sports Medicine 2017

Capturing effort and recovery: reactive and recuperative cortisol responses to competition in well-trained rowers British Journal of Sports Medicine

Blood-Borne Markers of Fatigue in Competitive Athletes – Results from Simulated Training Camps Plos One

Hormonal aspects of overtraining syndrome: a systematic review BMC Sports Science, Medicine and Rehabilitation 2017

Clusters of Athletes – A follow on from RED-S blog series to put forward impact of RED-S on athlete underperformance Dr N Keay, British Association of Sport and Exercise Medicine 2017

Strava Fitness and Freshness Science4Performance 2017

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

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

Addiction to Exercise

17 May 2017

ExerciseAddiction

Health is not just the absence of illness, but rather the optimisation of all components of health: physical, mental and social. Exercise has numerous benefits on all these aspects. However, a recent article in the British Medical Journal described how exercise addiction can have detrimental physical, mental and social effects.

Dedication and determination are valuable qualities required to be successful in life, including achieving sporting prowess. Yet, there is a fine line between dedication and addiction.

To improve sports performance, cumulative training load has to be increased in a quantified fashion, to produce an overload and hence the desired physiological and Endocrine adaptive responses. Integrated periodisation of training, recovery and nutrition is required to ensure effective adaptation. Sufficient energy availability and quality of nutrition are essential to support health and desired adaptations. On the graph above the solid blue line represents a situation of energy balance, where the demands of increased training load are matched by a corresponding rise in energy availability. This can be challenging in sports where low body weight confers a performance or aesthetic advantage, where the risk of developing relative energy deficiency in sport (RED-S) has implications for Endocrine dysfunction, impacting all aspects of health and sports performance.

Among those participating in high volumes of exercise, what distinguishes a healthy level of commitment from exercise addiction? Physical factors alone are insufficient: all those engaging in high levels of training can experience overuse injuries and disruption in Endocrine, metabolic and immune systems. Equally, in all these exercising individuals, overtraining can result in underperformance.

Psychological factors are the key distinguishing features between the motivated athlete and the exercise addict. In exercise addiction unhealthy motivators and emotional connection to exercise can be identified as risk factors. In exercise addiction the motivation to exercise is driven by the obsession to comply with an exercise schedule, above all else. This can result in negative effects and conflict in social interactions, as well as negative emotional manifestations, such as anxiety and irritability if unable to exercise, including the perceived necessity to exercise even if fatigued or injured.

Two categories of exercise addiction have been described. Primary exercise addiction is the compulsion to follow an excessive training schedule. Without balancing energy intake, the physical consequence may be a relative energy deficiency, as indicated on the graph by the dashed blue line. In secondary exercise addiction, the situation is compounded by a desire specifically to control body weight. These individuals consciously limit energy intake, almost inevitably developing the full clinical syndrome described in RED-S, dragging them down to the position indicated by the dotted blue line on the chart. These situations of exercise addiction can lead to varying risk categories of RED-S.

As described at the start of this blog, there is a blurred boundary between the dedicated athlete and the exercise addict. In practice there is most likely a cross over. For example, an athlete may start with healthy motivators and positive emotional connection to exercise, which can become a primary addiction to adhere rigidly to a training schedule, rather than putting the emphasis on the outcome of such training. In the case of an athlete where low body weight is an advantage, it is easy to appreciate how this could become a secondary exercise addiction, where the motivation for exercising becomes more driven by the desire to control weight, rather than performance.

In order to support those with exercise addiction, discussion needs to focus on adopting a more flexible approach to exercise, by recognising that exercise addiction has detrimental effects on all aspects of current and long term health. Furthermore, in the case of athletes, a multi-disciplinary approach is desirable to help the individual refocus on the primary objective of training: to improve performance. In all situations, discussion should explore modifications to exercise and nutrition, in order to prevent the negative effects of RED-S on health and performance.

Exercise has numerous health benefits and is usually viewed as positive behaviour. However, the outcome of exercise is related to the amount of training, appropriate nutrition and motivation for exercising.

For further discussion on Endocrine and Metabolic aspects of SEM come to the BASEM annual conference 22/3/18: Health, Hormones and Human Performance

References

Addiction to Exercise British Medical Journal 2017

Clusters of Athletes British Association of Sport and Exercise Medicine 2017

Sport performance and relative energy deficiency in sport British Journal of Sport Medicine 2017

Balance of recovery and adaptation for sports performance British Association of Sport and Exercise Medicine 2017

Optimal Health for all athletes Part 4 Mechanisms of RED-S British Journal of Sport Medicine 2017

Sports Endocrinology – what does it have to do with performance? British Journal of Sport Medicine 2017

Inflammation: Why and How Much? British Association of Sport and Exercise Medicine 2017

Sport Performance and Relative Energy Deficiency in Sport

11 March 2017

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

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

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

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

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

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

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

For further discussion on Endocrine and Metabolic aspects of SEM come to the BASEM annual conference 22/3/18: Health, Hormones and Human Performance

References

Teaching module RED-S British Association Sport and Exercise Medicine

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

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

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

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

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

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

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

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

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

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

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

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

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

Effects of adaptive responses to heat exposure on exercise performance

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

The Fatigued Athlete BASEM Spring Conference 2014

Relative Energy Deficiency in sport (REDs) Lecture by Professor Jorum Sundgot-Borgen, IOC working group on female athlete triad and IOC working group on body composition, health and performance. BAEM Spring Conference 2015.

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