Maximal oxygen uptake: "classical" versus "contemporary" viewpoints: a rebuttal

Area of Science:

• Exercise Physiology
• Cardiovascular Physiology
• Skeletal Muscle Physiology

Background:

• The 1996 J. B. Wolffe lecture's claims regarding A. V. Hill and exercise physiology are challenged.
• Key concepts like the "plateau phenomenon" and individual maximum oxygen consumption (VO2max) were erroneously attributed to Hill.
• Hill's actual beliefs centered on a universal VO2max and the exponential rise of VO2 at high running speeds.

Discussion:

• Examines the danger of a plateau in cardiac output (CO) and VO2 for the heart, linking it to myocardial oxygen delivery and ischemia.
• Discusses Hill's proposed "governor" mechanism to prevent myocardial ischemia during maximal exercise.
• Proposes a new physiological model where skeletal muscle recruitment is regulated by a central "governor" to prevent myocardial ischemia.

Key Insights:

• A. V. Hill did not establish the "plateau phenomenon" or individual VO2max; these concepts were misattributed.
• Cardiovascular function, specifically myocardial oxygen delivery, limits maximum exercise capacity.
• A central "governor" regulates skeletal muscle recruitment to prevent myocardial ischemia.

Outlook:

• The proposed model aligns with findings in hypobaric hypoxia, where myocardial hypoxia is more likely.
• Further research can explore the precise mechanisms of the central "governor" and its role in exercise limitation.
• This revised understanding impacts models of exercise physiology and athletic performance prediction.