In 2015, the American College of Sports Medicine, in conjunction with its annual meeting in San Diego, hosted a World Congress on "The Basic Science of Exercise Fatigue." Now, I am particularly excited to direct your attention to a special section in this month's MSSE® that reviews the presentations delivered by almost every scientific expert invited to present during this special fatigue meeting.
Webster's online dictionary provides a simple definition of fatigue as "the state of being very tired: weariness." Weariness is then defined as a condition of "lacking strength, energy, or freshness because of a need for rest or sleep," and tired is defined as "feeling a need to rest or sleep." These nontechnical definitions hint at the complexity of fatigue and by extension the reasons that scientists have yet to definitively identify its causative mechanisms. This complexity is illustrated by Congress keynote speaker Roger Enoka's emphasis on two key attributes of exercise fatigue: "1) performance fatigability – the decline in an objective measure of performance over a discrete period of time, and 2) perceived fatigability – changes in sensations that regulate the integrity of the performer."
At the Congress and in this month's special section, the basic mechanisms of exercise fatigue are addressed from multiple viewpoints. The reviews include a historical component, discussion about translation to performance, consideration of specific fatigue-associated agents such as reactive oxygen species and hydrogen ions, insights on the comparative physiology of fatigue, molecular mechanisms, and a summary of neural factors that may be involved. There are also an integrative perspective of fatigue and a discourse on disease and fatigue. One of the most exciting highlights of the World Congress, according to many of those in the audience that is also recapitulated in this month's special section was the debate about the role of acidosis in muscle fatigue by Håkan Westerblad and Bob Fitts. One senior scientist described this session as the highlight of his professional career at scientific conferences.
In my opinion, this special fatigue section in this month's MSSE® will be a valuable resource for students and researchers for many years to come. I encourage you to set aside some time to fully enjoy this cornucopia of research review delights.