Comparing Muscle Oxygenation and Peak Blood Lactate Concentration in Division 1 College Middle-Distance Athletes: A Speed Reserve Ratio Analysis

Middle-distance running requires a balance of aerobic and anaerobic energy systems, necessitating efficient physiological profiling for optimized training. Performance biomarkers, such as the Speed Reserve Ratio (SRR), have been used to improve training and performance but may not always be practical for routine assessment. Other biomarkers, such as skeletal muscle oxygenation (SmO₂) and blood lactate concentration ([La]bmax), may be more cost-effective and easier to integrate into training programs than the SRR. This study investigates the relationship between SmO₂ and [La]bmax with SRR in NCAA Division I middle-distance runners to determine whether these physiological markers could serve as viable alternatives for athlete profiling.

Male NCAA Division I athletes (n = 11) completed a series of sprint trials and incremental treadmill tests to assess SmO₂ and blood lactate responses.

The change in skeletal muscle oxygenation (ΔSmO₂) exhibited a significant positive correlation with SRR (r = 0.656, p = 0.028), while Reoxygenation Hemoglobin Slope (ROHS) displayed a negative correlation (r = -0.644, p = 0.033), suggesting that oxygen utilization and recovery kinetics differentiate athletes with higher anaerobic or aerobic capacities.

These findings highlight the potential of SmO₂-derived metrics as accessible, noninvasive alternatives for profiling aerobic–anaerobic balance in middle-distance runners, particularly in situations where SRR measurement is impractical or unavailable. Future research should explore how these markers integrate into training models, their predictive validity across different competition levels, and their application in optimizing individualized athlete development programs.

Integrating noninvasive SmO₂ monitoring can be a beneficial addition to training programs for enhancing performance outcomes in middle-distance runners.