Respiratory System as a Limiting Factor to Exercise Performance in Healthy Athletes

There is general consensus that the capacity of the respiratory system is overbuilt for the demands placed on ventilation and gas exchange by high-intensity exercise. In general, in a healthy population, the limiting factor to exercise performance at sea level is the capacity for maximal oxygen transport to the working muscle.

Endurance training induces large and significant adaptation within the cardiovascular and musculoskeletal system. However, the structural and functional properties of the lung and airways do not change in response to exercise training and, in elite athletes, the pulmonary system may become a limiting factor to exercise at sea level and altitude.

As a result of this respiratory paradox, highly trained athletes may develop upper airway obstruction, expiratory flow limitation, exercise-induced hypoxemia and respiratory muscle fatigue. All of this may influence exercise performance.