Locomotor & diaphragm muscle fatigue in endurance athletes

Published in the European Journal of Applied Physiology (August 2014, Volume 114, Issue 8, pp 1619-1633).


Locomotor and diaphragm muscle fatigue in endurance athletes performing time-trials of different durations
Thomas U. Wüthrich, Elisabeth C. Eberle, Christina M. Spengler


“Fatigue in leg muscles might differ between running and cycling due to inherent differences in muscle activation patterns. Moreover, postural demand placed upon the diaphragm during running could augment the development of diaphragm fatigue.”


“We investigated quadriceps and diaphragm fatigue in 11 runners and 11 cyclists.”


“Different levels of leg muscle fatigue in runners and cyclists could in part be related to the specific muscle activation patterns including concentric contractions in both modalities but eccentric contractions in runners only. Diaphragm fatigue likely resulted from the large ventilatory load which is characteristic for both exercise modalities and which was higher in 15TTs than in 30TTs (+27 %, p < 0.01) while postural demand appears to be of less importance.”

Thankfully there is something you can do to help alleviate diaphragm fatigue. Like any other muscle group you can train your breathing muscles (which includes your diaphragm) with POWERbreathe Inspiratory Muscle Training. Click on the links below to find out more about:

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Respiratory disorders in endurance athletes

Open Access article published in the Journal of Sports Medicine April 2nd 2014.


Respiratory disorders in endurance athletes – how much do they really have to endure?


“Respiratory disorders are often a cause of morbidity in top level endurance athletes, more often compromising their performance and rarely being a cause of death… Both bronchospasm and the onset of interstitial edema induced by exercise cannot be considered pathological per se, but are more likely findings that occur in several healthy subjects once physical exhaustion during exertion has been reached. Consequently, we get a vision of the respiratory system perfectly tailored to meet the body’s metabolic demands under normal conditions but which is limited when challenged by strenuous exercise, in particular when it happens in an unfavorable environment.”

The prevalence and incidence of exercise-induced respiratory disorders in athletes

“In sports requiring strenuous endurance training, athletes are obliged to inspire large volumes of air, and for this reason an increased risk of developing EIA/EIB (Exercise-Induced Asthma/Exercise-Induced Bronchoconstriction) may be expected. This risk is further increased if athletes are exposed to cold air.”

Conclusion and future direction

“With the state of current knowledge, cardiac problems are not the only cause of morbidity and mortality among endurance athletes. For this reason, the above mentioned meaningful evidence of respiratory disorders in endurance athletes deserves to be widespread knowledge both in the scientific and in the athletic international community. As a matter of fact, paying attention to the concept that the respiratory system may show a pathophysiological limitation to endurance performance and sometimes be a cause of illness or even death is definitely the first step…”

…“In conclusion, taking up the question of the title of this report, we can say that every endurance athlete has their own limit in endurance training that once passed will produce all the possible respiratory disorders previously described. The question is precisely to understand if there is a limit in terms of intensity and/or in terms of duration in years to endurance training, before respiratory disorders can appear, and if we can apply any preventive strategies. To be an endurance champion, this inevitably means accepting all the labors of strong training but also enduring all possible health problems caused by the same.”

View the full article.

View list of published research that used POWERbreathe as the IMT intervention of choice in POWERbreathe in Research.

Find more published research on our Inspiratory Muscle Training Research blog.