Abstract
BACKGROUND:
Gender-based delta blood lactate concentration (Δ [BLa
-
]) differences may be impacted by the volume of work performed during exercise. Thus workload can act as a confounding influence when data from men and women are compared.
OBJECTIVE:
To examine workload's impact on gender-based disparities in delta blood lactate concentration (Δ [BLa
-
]) values from supramaximal exercise.
METHODS:
Subjects (49 women, 31 men) did two workouts on an exercise device (Impulse Technologies; Newnan, GA) comprised solely of either tonic or phasic repetitions. Total work (TW) and Δ [BLa
-
] were quantified from each workout. TW and raw Δ [BLa
-
] values were each examined with 2 × 2 ANOVAs, with repeated measures for workout. Δ [BLa
-
] values were also examined with TW as a covariate using a 2 × 2 ANCOVA and repeated measures for workout.
RESULTS:
Raw Δ [BLa
-
] and TW results each yielded predictable inter-gender differences. However our ANCOVA data produced a two-way interaction and the following significant differences: men-phasic, women-phasic > women-tonic > men-tonic.
CONCLUSIONS:
Our results support the idea that the volume of TW performed exacerbates inherent metabolic differences among men and women that heighten gender-based blood lactate differences. Future research on inter-gender lactate differences should consider workload as a covariate.