Carbon Dioxide Expiration and Performance Fatigability Following Aerobic Exercise Training: A Longitudinal,...

Area of Science:

• Exercise Physiology
• Cardiorespiratory Function
• Metabolic Adaptation

Background:

• Aerobic exercise training (AET) is known to improve cardiorespiratory function and reduce fatigability.
• The specific mechanisms linking AET to reduced fatigability, particularly in relation to carbon dioxide expiration (VCO2) components, require further elucidation.
• Understanding these adaptations is crucial for clinical populations with reduced exercise capacity.

Purpose of the Study:

• To investigate the impact of a vigorous 4-week AET regimen on components of carbon dioxide expiration (VCO2).
• To assess the influence of AET on cardiorespiratory function and fatigability in healthy adults.
• To determine the relationship between VCO2 components and fatigability post-AET.

Main Methods:

• Twenty healthy adults underwent peak cardiopulmonary exercise (CPX) and submaximal tests before and after a 4-week AET program.
• Fatigability was measured by endurance test duration and power output.
• Respiratory buffering (excess VCO2) and metabolic VCO2 were calculated and analyzed using regressions and paired t-tests.

Main Results:

• A significant improvement in all measures of fatigability was observed following AET.
• Excess VCO2 significantly increased post-AET, while metabolic VCO2 did not show a significant change.
• Excess VCO2 was identified as a strong predictor of fatigability.

Conclusions:

• AET can independently influence respiratory buffering and metabolic components of VCO2.
• The adaptation of respiratory buffering to AET may play a significant role in improving fatigability.
• These findings provide a plausible mechanism for AET-induced fatigability improvements, relevant to both healthy individuals and clinical populations.