Effect of an endurance triathlon on pulmonary function

Area of Science:

• Exercise Physiology
• Pulmonary Function Testing
• Sports Medicine

Background:

• Endurance events like triathlons place extreme demands on the respiratory system.
• Understanding the impact of prolonged physical exertion on lung function and respiratory muscle strength is crucial for athletes and clinicians.

Purpose of the Study:

• To evaluate the effects of a full-distance triathlon on spirometry, respiratory muscle strength, and maximal voluntary ventilation.
• To assess the recovery of pulmonary function and muscle strength after a triathlon.

Main Methods:

• Twelve male triathletes were tested before, after each segment (swim, bike, run), and the morning after a 3.8-km swim, 180-km bike, 42-km run triathlon.
• Measurements included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory flow between 25-75% of FVC (FEF25-75%), forced expiratory flow at 50% of FVC (FEF50%), maximal voluntary ventilation (MVV), inspiratory muscle strength (PImax), and expiratory muscle strength (PEmax).

Main Results:

• Significant post-triathlon declines were observed in FVC (7.1%), FEV1 (8.4%), FEF25-75% (15.2%), and FEF50% (18.6%).
• Inspiratory muscle strength (PImax) decreased significantly after the bicycle (26%) and running (25%) segments, with full recovery by the next morning.
• Maximal voluntary ventilation (MVV) and expiratory muscle strength (PEmax) did not show significant changes.

Conclusions:

• Participation in an endurance triathlon leads to temporary reductions in vital capacity and expiratory flow rates.
• Inspiratory muscle function is impaired following prolonged cycling and running, but recovers relatively quickly.
• The respiratory system, particularly expiratory flow rates and inspiratory muscle strength, is significantly affected by extreme endurance exercise.