Does the Menstrual Cycle Impact the Maximal Neuromuscular Capacities of Women? An Analysis Before and After a Graded Treadmill Test to Exhaustion

Abstract

Morenas-Aguilar, MD, Ruiz-Alias, SA, Blanco, AM, Lago-Fuentes, C, García-Pinillos, F, and Pérez-Castilla, A. Does the menstrual cycle impact the maximal neuromuscular capacities of women? An analysis before and after a graded treadmill test to exhaustion. J Strength Cond Res 37(11): 2185-2191, 2023. This study explored the effect of the menstrual cycle (MC) on the maximal neuromuscular capacities of the lower-body muscles obtained before and after a graded exercise test conducted on a treadmill to exhaustion. Sixteen physically active women were tested at -11 ± 3, -5 ± 3, and 5 ± 3 days from the luteinizing peak for the early follicular, late follicular, and midluteal phases. In each session, the individualized load-velocity (L-V) relationship variables (load-axis intercept [L0], velocity-axis intercept [v0], and area under the L-V relationship line [Aline]) were obtained before and after a graded exercise test conducted on a treadmill to exhaustion using the 2-point method (3 countermovement jumps with a 0.5-kg barbell and 2 back squats against a load linked to a mean velocity of 0.55 m·second-1). At the beginning of each session, no significant differences were reported for L0 (p = 0.726; ES ≤ 0.18), v0 (p = 0.202; ES ≤ 0.37), and Aline (p = 0.429; ES ≤ 0.30) between the phases. The MC phase × time interaction did not reach statistical significance for any L-V relationship variable (p ≥ 0.073). A significant main effect of "time" was observed for L0 (p < 0.001; ES = -0.77) and Aline (p = 0.002; ES = -0.59) but not for v0 (p = 0.487; ES = 0.12). These data suggest that the lower-body maximal neuromuscular capacities obtained before and after a graded treadmill test are not significantly affected by MC, although there is a high variability in the individual response.