Impact of Isolated Exercise-Induced Small Airway Dysfunction on Exercise Performance in Professional Male Cyclists

Area of Science:

• Sports Medicine
• Respiratory Physiology
• Exercise Science

Background:

• Professional cycling places extreme demands on the respiratory system.
• Exercise-induced bronchoconstriction (EIB) is prevalent in athletes.
• Small airway dysfunction (SAD) can occur in isolation or with reduced FEV1.

Purpose of the Study:

• Investigate isolated exercise-induced SAD in professional cyclists.
• Assess the impact of isolated SAD on exercise capacity in this population.

Main Methods:

• Recruited professional cyclists without asthma or atopy.
• Measured anthropometrics, training age, spirometry, FeNO, and IgE.
• Conducted cardiopulmonary exercise testing (CPET) followed by spirometry.

Main Results:

• Isolated SAD showed increased 1-FEV3/FVC compared to controls.
• Exercise capacity was lower in isolated SAD cyclists than controls, similar to EIB.
• Isolated SAD was associated with worse ventilatory reserve (VE/MVV%).

Conclusions:

• Strenuous endurance exercise can cause airway injury and repair cycles in cyclists.
• This process may lead to airway hyper-responsiveness, inflammation, and fibrosis.
• Isolated SAD in cyclists is linked to diminished exercise capacity.