Indirect Markers of Muscle Damage Throughout the Menstrual Cycle

Abstract

Context: The indirect markers of muscle damage have been previously studied in females. However, inconclusive results have been found, possibly explained by the heterogeneity regarding monitoring and verification of menstrual-cycle phase. Purpose: To determine whether the fluctuations in sex hormones during the menstrual cycle influence muscle damage. Methods: A total of 19 well-trained eumenorrheic women (age 28.6 [5.9] y; height 163.4 [6.1] cm; weight 59.6 [5.8] kg body mass) performed an eccentric-based resistance protocol consisting of 10 × 10 back squats at 60% of their 1-repetition maximum on the early follicular phase (EFP), late follicular phase, and midluteal phase of the menstrual cycle. Range of motion, muscle soreness, countermovement jump, and limb circumferences were evaluated prior to 24 and 48 hours postexercise. Perceived exertion was evaluated after each set. Results: Differences in sex hormones indicated that tests were adequately performed in the different menstrual-cycle phases. Prior to exercise, muscle soreness was higher in the EFP (4.7 [7.7]) than in the late follicular phase (1.1 [3.2]; P = .045). No other variables showed significant differences between phases. Time-point differences (baseline, 24, and 48 h) were observed in knee range of motion (P = .02), muscle soreness, countermovement jump, and between sets for perceived exertion (P < .001). Conclusion: Although the protocol elicited muscle damage, hormonal fluctuations over the menstrual cycle did not seem to affect indirect markers of muscle damage, except for perceived muscle soreness. Muscle soreness was perceived to be more severe before exercise performed in EFP, when estrogen concentrations are relatively low. This may impair women’s predisposition to perform strenuous exercise during EFP.

A Pilot Study on the Impact of Menstrual Cycle Phase on Elite Australian Football Athletes

“…Perceived soreness and exertion appeared to be unaffected by MC phase. This is in contrast with the findings of previous studies that have found, under standardised conditions, muscle soreness before [ 42 ] and immediately post exercise [ 43 ] is greatest in the early follicular phase. However, delayed onset muscle soreness (24 and 48 h post-exercise) was not significantly affected by MC phase [ 43 ].…”

Influence of Menstrual Cycle on Leukocyte Response Following Exercise-Induced Muscle Damage

“…Therefore, the current protocol successfully induced muscle damage, but no significant differences were observed between the two groups in each measure. As a previous study reported no phase differences in indirect markers of muscle damage after eccentric exercise [ 37 ], differences in ovarian hormone concentrations in MCs are not expected to affect the indirect markers of muscle damage.…”

“…This study recruited individuals with between-group differences by prioritizing the exclusion of the repeated bout effect, which should be considered in data comparisons. Originally, this study was supposed to use a random crossover design; however, previous studies that used a crossover design were influenced by the repeated bout effect, which is characteristic of eccentric exercise due to the short period between each bout of exercises [ 32 , 37 ]. Thus, although the results of the present study may be more influenced by individual differences in ovarian hormone concentrations than by the random crossover design, we evaluated a complete methodology for MC phase verification.…”

Exercise-Induced Muscle Damage in Postmenopausal Well-Trained Women

“…These eumenorrheic participants were analyzed earlier to observe the muscle damage response between menstrual cycle phases. 26,27 Further exclusion criteria included (1) the use of any hormonal contraception or HRT in the 6 months preceding the study, (2) any pregnancies in the year preceding the study, (3) any existing disease and/or metabolic or hormonal disorder, (4) any musculoskeletal injury in the past 6 months, (5) any surgery interventions (ie, ovariectomy) or other medical conditions that would be exacerbated by an eccentric resistance exercise protocol, (6) the regular use of medication or dietary supplements that could affect the results, and (7) smoking. A written informed consent was obtained from each participant.…”

“…Verification of menstrual cycle phases in eumenorrheic participants was performed according to the studies carried out previously by our research group, 26,27 following the methodological recommendations based on a 3-step method 16 including (1) calendar counting, (2) home urine tests to detect luteinizing hormone (LH) surge and the subsequent ovulation between 14 and 26 hours later, 16 and (3) blood hormones' analysis.…”