O2 Pulse Patterns in Male Master Athletes with Normal and Abnormal Exercise Tests

Area of Science:

• Cardiology
• Sports Medicine
• Exercise Physiology

Background:

• Abnormal exercise testing (ET) results, defined by ST segment depression, in athletes without obstructive coronary artery disease (CAD) lack clear clinical interpretation.
• It remains uncertain if these findings represent physiological adaptations to intense training or true myocardial ischemia with an attenuated stroke volume (SV) response.

Purpose of the Study:

• To investigate whether athletes with abnormal ET results but no obstructive CAD exhibit an attenuated SV response.
• To utilize cardiopulmonary ET parameters to assess SV response in this specific athlete population.

Main Methods:

• Cardiopulmonary exercise testing (ET) was performed on 78 male master athletes with abnormal ET results and no obstructive CAD.
• Key parameters including oxygen pulse to work rate (ΔO2 pulse/ΔWR), oxygen uptake to work rate (ΔV˙O2/ΔWR), and heart rate to work rate (ΔHR/ΔWR) were analyzed.
• These athletes were compared to 78 matched male master athletes with normal ET results.

Main Results:

• Athletes with abnormal ET showed a significantly lower ΔO2 pulse/ΔWR ratio beyond the anaerobic threshold compared to those with normal ET (0.73 ± 0.41 vs. 1.12 ± 0.54, P < 0.001).
• A decreased ΔV˙O2/ΔWR ratio (0.9 ± 0.2 vs. 1.0 ± 0.3, P = 0.041) and an increased ΔHR/ΔWR ratio in the final exercise minutes (1.19 ± 0.5 vs. 0.80 ± 0.6, P < 0.001) were observed in the abnormal ET group.

Conclusions:

• Athletes with abnormal ET and no obstructive CAD demonstrate an attenuated O2 pulse slope, reduced ΔV˙O2/ΔWR, and elevated ΔHR/ΔWR beyond the anaerobic threshold.
• These findings support the hypothesis that a portion of athletes with abnormal ET results, despite the absence of obstructive CAD, may experience an attenuated SV response during high-intensity exercise.