Category Archives: physiology

Bernal’s ‘amazing engine’: how do endurance athletes’ hearts differ?

By Nichola Kentzer

Many will remember the 2019 Tour de France for its premature finish caused by hailstorms and landslides, rather than the incredible achievements of the endurance athletes. To complete the 21 stages spanning 3,480 kilometres is an extraordinary feat – but what is it about these athletes that allows them to do it? The physiology of a Tour de France rider has been examined in depth by scientists (e.g. Santalla and colleagues in 2012), but in this short article we will be focusing on just one aspect, the heart.

The heart of the matter

Chris Froome described Egan Bernal, the 2019 Tour champion, as having ‘an amazing enginereferring to Bernal’s heart, the muscular pump, that drives blood around the body to perform essential functions. Located in the left-hand side of the chest and typically about the size of a clenched fist, Bernal’s heart’s ability to pump the required oxygen to his working muscles to complete the mountain climbs and long distances, is the key to his success.

We can make such statements because, on examination, as the athlete trains their hearts get bigger and stronger meaning they can pump more blood per beat. Indeed, athletes often have a larger than usual left ventricle, developed through conditioning the body to be as efficient as possible. Referring to these adaptations to training, Bradley Wiggins was described as have a heart ‘like a bucket’ after his 2012 Tour victory.

Because of this increased efficiency, and the trained heart’s ability to pump more blood per beat, a key indicator of an endurance athlete’s heart efficiency is their resting heart rate. Where an average adult’s resting heart rate might be between 60-90 beats per minute (bpm), a Tour de France cyclist can have readings of lower than 40 bpm. Physiological tests carried out on Chris Froome by Team Sky to quash doping allegations after his Tour successes, showed that his resting heart rate dropped as low as 29 bpm.

Cycling is not the only sport that produces these super athletes. Biathlon, combining cross country skiing with precision target shooting, is widely recognised as one of the most challenging winter endurance events. Indeed, the two activities seem unlikely partners with one requiring strength, speed and endurance and the other requiring concentration and a steady hand (while your heart is still thumping from the exertion!).

Top French biathlete, Martin Fourcade, winner of over 20 World Championship medals, over 120 World Cup medals and seven Olympic medals posted his own resting heart rate readings on his Instagram account in 2017. He reported an incredible 25 bpm. Although this reading is his own, and biathletes do specifically train to lower their heart beat to enable more accurate shooting, the value is incredible considering the lowest resting heart rate on record is 27 bpm.

This level of efficiency can also be examined through a second measure: cardiac output the amount of blood ejected from the left ventricle in one minute. It is calculated by multiplying the person’s heart rate by their stroke volume (amount of blood pumped from the left ventricle in a single heart beat). Therefore, with the trained endurance athlete’s larger left ventricle and lower resting heart rate, they can pump out more blood per beat and their heart needs to beat less frequently to achieve the same cardiac output.

And for those of us who are not elite endurance athletes?

Comfortingly for us mere mortals, and important knowledge for those working in the sport and fitness industry, regular exercise (not necessarily long-distance cycling!) improves heart health and increases cardiac output. This enables us to reduce our resting heart rates and for our bodies to become more efficient, even if not to the extreme levels of the athletes discussed above. So instead of sitting at your desk during your lunch break take a brisk walk, opt for the stairs, and park a few hundred metres further from the supermarket entrance, as these small changes can all improve your heart and most importantly your health.

Abstract Call for 4th Annual OU Sport & Fitness Conference – My Child: The Athlete

My Child: The Athlete

Tickets are on sale now – Click here to register!

The 4th annual OU Sport and Fitness Conference focuses on youth development in sport with particular attention paid to contemporary issues such as:

  • Youth physical development

    E.g. Strength and conditioning, injury prevention, physical literacy, skill acquisition

  • Psychological development

    E.g. Building resilience, coping with and learning from failure

  • Parental support for talented athletes

    E.g. Research to support parents of talented athletes, effects on siblings and family members, family dynamics and youth development

  • Coaching considerations when working with children

    E.g. planning training and practice, coaching behaviours, managing expectations, managing the needs of each athlete

With three world-leading keynotes confirmed, this promises to be an illuminating and thought provoking two days:

Toni Minichiello – Coach to GB’s 2012 gold medal-winning Olympian Jessica Ennis-Hill. (Day 1 evening keynote presenter)

Dr Jean CôtéProfessor at Queen’s University, Canada and world-renowned researcher within the fields of youth sports and coach development. @JeanCote46

Dr Camilla Knight – Associate Professor at Swansea University and leading expert on the psychosocial experiences of children in sport, with a particular focus upon the influence of parents. @cjknight

Whether you’re an academic, a student, a coach, teacher or parent, we invite you to join us for two action packed days full of dissemination, discussion, and learning opportunities.

Call for Abstracts (Now Open for Submissions):

The OU Sport and Fitness Conference team invites the submission of abstracts for consideration as either an oral or poster presentation. Submissions may have either an academic or applied focus resonating with the themes of the conference (see above bullet points). We would also welcome submissions which report on research in progress or the initial stages of development.

Please download the abstract submission guidelines here:

Abstract Submission Guidelines


Click here to register!

Full conference packages:
Access to the whole two days – keynotes and breakout sessions
Three course conference dinner on day 1*
Lunch and refreshments on both days

*Please note – we have a limited number of tickets for the evening session – book early to avoid disappointment.

Evening only package*:
Access to the evening session on day 1
Keynote presentation from Toni Minichiello
Q&A Panel with Toni, Dr Jean Côté and Dr Camilla Knight
Three course conference dinner

*Please note – the evening session will take place at Kents Hill Park Training and Conference Centre, MK7 6BZ. There are a limited number of tickets available for this session so please book early to avoid disappointment. 


Don’t forget to follow us for all the latest conference updates: @OU_SportConf and use the hashtag #OUSportConf to share that you’ve registered!


We look forward to welcoming you to My Child: The Athlete in March 2019!

For any conference queries please contact


Golden Oldies!

By Ben Langdown

Late nights watching Olympic and Paralympic sport have been a highlight of my summer and it has been absolutely incredible. The lack of sleep has aged me considerably but it has been worth every second to see all the amazing stories unfold.

The media has always loved a story of winning against all odds. In particular, with regard to age:

Too young to win – but look out for them in Tokyo!

Long past their prime – far too old for a spot on the podium!

And then it happens as quinquagenarians pop up and win Olympic and Paralympic gold medals! 15 year olds win medals in varying events and spark a flurry of news reports on success at such a young age.

Male Life Cycle

But why should we be so surprised about athletes young and old winning medals?

As we age many changes take place within our bodies as we develop and train towards peak physiological age of between 20-39 years old, dependant on the sport or event (Allen & Hopkins, 2015). Our muscles grow bigger, stronger and faster, the heart increases in size and can pump with greater force and capacity meaning we can run for longer, row harder or swim faster (see Lloyd and Oliver, 2013 for a full review of youth physical development). As we adapt to aerobic training we experience an array of changes in and around our muscles including an increase in the size and number of mitochondria which are the energy producing powerhouses in muscle cells (NSCA, 2016). This increase results in more energy for muscle contractions and allows us to go:

 Citius, Altius, Fortius!

 Then we hit the slippery slope…I am not even going to search the Latin for ‘Slower, Lower, Weaker’, but you get the idea! From the age of 30 the body’s systems, responsible for our peak performances, will stand at the top of the slope and look down (Spirduso et al, 2005). Now begins the slow, gradual descent that reverses all the good things their childhood, adolescence, and early adulthood years brought them, reducing an athlete’s chances of success.

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After the landmark 30th birthday the following changes start to take place at even the highest levels of sport:

  • Decreases in strength and power due to decreases in muscle mass and increases in intramuscular fat (Rodriguez et al., 2009).
  • Decreased muscular endurance, resting metabolic rate and increased body fat (NSCA, 2016).
  • Cardiac output decreases at a rate of 1% per year as does V̇O2Max, averaging 1% per year from 25 – 75 years (Jackson et al., 1996; Schvartz & Reibold, 1990 as cited in Garber & Glass, 2006).

For example, performance in competitive weightlifting declines by 1-1.5% per year until 70, after which the performance decrement gets even greater (Meltzer, 1994, as cited in NSCA, 2016).

A note of caution – the physiological adaptations to ageing are dependent on the individual, the amount of physical activity, the environment, and disease (Garber & Glass, 2006)).


This summer athletes have been pushing the boundaries of their physiological clocks; whether this is the result of training or through sheer determination to succeed one last time…

Take Elizabeth Kosmala, a 9-time gold medallist competing in her 12th Paralympics at the age of 72. Okay, she started out as a swimmer and has since switched to the less physically demanding event of shooting, but it is still an achievement to be competing at the top level in her category.

How about 50-year-old Kazakh, Zulfiya Gabidullina who won her country’s first-ever Paralympic Games medal with a world record breaking performance in the S3 class 100m freestyle swimming. Allen and Hopkins (2015) reported that swimmers generally peak around the age of 20! What’s even more impressive is that she didn’t even start training for swimming until her 30s!

Nick Skelton is another great example, at 58 years old, overcoming the physical demands of equestrian events to take individual jumping gold with his horse, Big Star, himself also a veteran (in horse terms!) at 13 years old!

At the other end of the spectrum the youngsters have also picked up medals in both the Olympics and Paralympics. Most notably the likes of gymnast Amy Tinkler (16 yrs), bronze medallist and the youngest member of #TeamGB, swimmers Ellie Robinson (15 yrs, S6) and Becky Redfern (16 yrs, SB13). Also athletes such as Kare Adenegan (15 yrs, T34) and Ntando Mahlangu (14 yrs, T42), who took the 200m silver behind #ParalympicGB’s Richard Whitehead (40 yrs) which is surely one of the biggest age gaps between gold and silver winning athletes!

It is easy to get drawn into the stories surrounding performances but we must pause for a moment and consider the factors potentially allowing them to happen. Let’s take the young competitors first, there is a high possibility that, physically, they have developed earlier than a lot of their peers and are therefore ready to compete at the highest level. Yes, there will be training and physiological adaptations to come but they could be, what are known as, early maturing individuals (Lloyd et al., 2014). arztsamui arztsamui

As for the older competitors, especially at the Paralympics, we have to look at the talent pool from which they are emerging. A small talent pool allows athletes to compete for longer and achieve better results than they would if this talent pool were to grow. For example, the women’s 100m freestyle event in swimming, at the Olympics this event was won by Simone Manuel, a 20 year old American. She came from a pool of over 500 swimmers who, on the Fina world ranking list, are all within 5 seconds of each other, thus there is an abundance of swimmers competing on that world stage. Conversely, 50-year-old Paralympian gold medallist Gabidullina has succeeded from a talent pool of 19 swimmers listed on the S3 IPC world rankings, only one of whom was within 5 seconds of her time.

Of course there are many other variables I have not discussed and it is never an exact science to say who will win and at what age, but to even qualify for either of the Games there are times and standards in place, albeit put in place by each home country. So, as the Paralympics continue to thrive following the success of the London 2012 and Rio 2016 Games, it is possible that these talent pools will grow therefore reducing the amount of stories we hear of the super quinquagenarians achieving Citius, Altius, Fortius!



Allen, S. V., & Hopkins, W. G. (2015). Age of peak competitive performance of elite athletes: a systematic review. Sports Medicine, 45(10), 1431-1441.

Lloyd, R. S., Oliver, J. L., Faigenbaum, A. D., Myer, G. D., & Croix, M. B. D. S. (2014). Chronological age vs. biological maturation: implications for exercise programming in youth. The Journal of Strength & Conditioning Research, 28(5), 1454-1464.

Lloyd, R. S., & Oliver, J. L. (2012). The youth physical development model: A new approach to long-term athletic development. Strength & Conditioning Journal, 34(3), 61-72.

Garber, C. E., & Glass, S. C. (2006). ACSM’s resource manual for guidelines for exercise testing and prescription. L. A. Kaminsky, & K. A. Bonzheim (Eds.). Baltimore, MD: Lippincott Williams & Wilkins.

Haff, G. G., & Triplett, N. T. (Eds.). (2016). Essentials of Strength Training and Conditioning 4th Edition. Human kinetics.

Rodriguez, N. R., DiMarco, N. M., & Langley, S. (2009). Position of the American dietetic association, dietitians of Canada, and the American college of sports medicine: nutrition and athletic performance. Journal of the American Dietetic Association, 109(3), 509-527.

Spirduso, W. W., Francis, K. L., & MacRae, P. G. (2005). Physical dimensions of aging, 2nd Ed. Human Kinetics, Champaign, IL.


The road to ruin: are Ultra-endurance events worth the risk?

By Candice Lingam-Willgoss

Sport, exercise and physical activity hold different significance and meaning to every individual, whether it is a part of your daily life, something you watch from a distance or something all-consuming that defines who you are. Maintaining a regular routine of exercise is frequently cited as being highly effective for prevention and treatment of many chronic diseases and unequivocally improves cardiovascular health (Sharkey and Gaskill, 2007). However, with ever growing participation in ultra-endurance events all over the world research has started to look in more detail at the impact this type of exercise has on the human body (IAU Ultra Marathon, 2013).  Ultra-endurance is the term given to events that last for over 6 hours, with the term ultra-running being applied to distances over a marathon distance of 26.2 miles (Wortley and Islas, 2011).  People seem to seek out these ultra-type events in order to test themselves, with Hinton (2016) a former double ironman competitor reporting ‘Ironman didn’t break me, mentally or physically.  I wanted to know my limits’ and while this form of challenge carries with it a huge sense of achievement and success, is there a downside to it all?

Watching the actor/comedian Eddie Izzard take on yet another ultra-marathon event in the name of Sport Relief is a prime example of the potential downside to endurance competition. Izzard is currently embarking on the challenge of 27 marathons in 27 days, and while he has already earned the title Marathon Man following his 2009 achievement of 47 marathons in 51 days this current challenge (one he failed to complete in 2012) carries with it the additional factor of 30 degree heat (Izzard, 2016).  Izzard doesn’t look well, he was forced to take a rest day on day 5, and now three days later the strain on his body is starting to visibly show (BBC, 2016).  The warning 4 years ago was that if he didn’t stop he would die (Izzard, 2016), but is the challenge worth the potentially permanent damage he could do to his body?

Physical Effects

Many of us have experienced delayed onset of muscle soreness (DOMS) which tends to occur 24 hours after exercise (Sharkey and Gaskill, 2007). Although uncomfortable DOMS will probably be the least of Izzard’s worries. Endurance events put increased stress on the body, in particular on the immune system making a person vulnerable to risk of infection (Walsh, et al, 2011). Specifically, a substantial body of work accumulated over the last 20 years has shown that intense endurance exercise, such as running, swimming, cycling or rowing results in significant changes in white blood cell count (Lancaster and Febbraio, 2016). While exercise is universally shown to have health benefits (up to one hour daily), researchers looking at long distance races have cautioned that as well as inhibiting the immune system this form of exercise may lead to overload of the heart atria and right ventricle which could ultimately make someone more prone to unfavorable heart arrhythmias later in life (O’Keefe, et al, 2012).

That said there is much contrary evidence to support that those who do participate in ultra-sport in a measured manner are very happy and due to the slower paced and reduced impact compared to elite marathon runners actually get far less overuse injuries (Wortley and Islas, 2011).  Research by Krouse et al, which looked at female ultra-runners also concluded that they tended to have much better mental health, and psychological coping strategies (2011).


An interesting factor that could actually be in Izzard’s favour is his age, research into this area has found that being over 40 can be a huge advantage when it comes to endurance sport. Knechtle et al (2012) found that when looking at results from the 100km ultra-marathon the percent of finishers significantly increased for the 40–49 and the 50–59-year age groups indicating that this is an optimum age to compete in these type of events. This was also echoed by Hoffman and Krishnan, (2014) who found that runners over 40 tended to have a lower occurrence of injury. Another key benefit of age is that it comes with a higher level of resolve, older athletes tend to have more mental strength than younger athletes (Li, 2016 cited in BBC, 2016). So while we see Izzard ‘physically wilting’ his determination is at an all time high, giving him the willpower to push on (BBC, 2016).

What’s clear is that endurance sport is a way of life, and that ultra-athletes are a unique subculture of people who are striving to challenge themselves both mentally, physically and emotionally. I am constantly in awe of many of my friends who take on such extreme and challenging competitions, whether they are competing in 24 hour running races or 250km treks across the desert. Their motives are pure, as Varvel a multiple ultra-competitor sums up, saying there is a sense of ‘self-fulfilment’ and these varied experiences are seen as ‘life-affirming’ (2016). The primal desire to be at one with nature and bond with others in the face of adversity are all needs that are met by the world of ultra-racing.


BBC. (2016). How will 27 marathons affect Eddie Izzard. BBC News. Available at Accessed 28th February 2016.

BBC, (2016). Marathon Man. Available at . Accessed 1st March 2016.

Hinton, L. (2016) Personal Communication. 24th February 2016.

Hoffman, M.D. and Krishnan, E. (2014). Health and Exercise-Related Medical Issues among 1,212 Ultramarathon Runners: Baseline Findings from the Ultrarunners Longitudinal TRAcking (ULTRA) Study. PLOS. 10. Available at Accessed 29th February 2016

IAU Ultra Marathon. (2013), available at accessed 1st March 2016

Izzard, E. (2016). Marathon Man. Available at Accessed 1st March 2016.

Knechtle, B., Rust, C.A., Rosemann, T. and Lepers, R. (2012). Age-related changes in 100-km ultra-marathon running performance. Age. 34 (4), 1033-1045.

Krouse, R.Z., Ransdell, L.B., Lucas, S.M. and Pritchard, M.E. (2011). Motivation, Goal Orientation, Coaching and Training Habits of Women Ultrarunners. Journal of Strength and Conditioning Research. 25 (10), 2835-2842.

Lancaster, G.I. and Febbraio, M.A. (2016). Exercise and the immune system: implications for elite athletes and the general population. Immunology and Cell Biology. 94. 115-116.

O’Keefe, J.H., Patil, H.R., Lavie, C.J. et al. (2012). Potential adverse cardiovascular effects from excessive endurance exercise. Mayo Clinic Proceedings, 87(6), 587-595.

Sharkey, B.J. and Gaskill, S.E. (2007) Fitness and Health. Champaign. Human Kinetics

Varvel, M. (2016). Personal Communication. 24th February 2016.

Walsh, N.P., Gleeson, M., Shepard, R.J. (2011). Position Statement Part One: Immune function and exercise. Exercise Immunology Review, 17, 6-63

Wortley, G. and Islas, A.A. (2011). The problem with ultra-endurance athletes. British Journal of Sports Medicine. 45 (14), 1085.