Influence Of The Menstrual Cycle On Muscle Damage Marker And Leukocyte Reaction Following Eccentric Exercise

Abstract

PURPOSE:Ovarian hormone could inhibit exercise-induced muscle damage and leukocyte infiltration. Premenopausal women experience ovarian hormonal changes by the menstrual cycle (MC); therefore, MC could be related to muscle damage and leukocyte reaction, although it is not be clear. The purpose of this study was to investigate how MC could influence serum creatine kinase (CK) and leukocyte reaction following eccentric exercise. METHODS: Twenty-two untrained women with eumenorrhea (age 27.0 ± 6.4 years; height 160.1 ± 4.2 cm; weight 57.8 ± 7.0 kg; and body mass index 22.5 ± 2.3 kg/m2 [mean ± SD]) participated in the study. The subjects performed 10 sets of 6 repetitions of eccentric exercises with their nondominant arm in the early follicular phase (E-FP, n = 12) or midluteal phase (M-LP, n = 10). Blood samples were collected pre-exercise (PRE) and 4, 48, and 96 hours (h) post-exercise (POST) to analyze serum estradiol (E2) and progesterone (P4) concentration, serum CK, leukocyte count, and leukocyte fractionation (neutrophils, lymphocyte, monocyte, and other leukocytes). We assessed the isometric strength of elbow flexion, range of motion in the elbow joint, upper arm circumference and visual analog scale rating of perceived muscle soreness at PRE, immediately post, POST 4, 48, and 96 h. RESULTS: The serum E2 concentrations at PRE were significantly higher in the M-LP than the E-FP (E-FP 42.9 ± 18.6 vs. M-LP 186.4 ± 98.6 pg/mL; p < 0.01). The serum P4 concentrations at PRE were significantly higher in the M-LP than the E-FP (E-FP 0.2 ± 0.1 vs. M-LP 15.0 ± 3.1 ng/mL; p < 0.01). Significant time effects were present for serum CK at PRE to POST 48 h and 96 h (p < 0.05). No MC phase effect could be observed. The percent change in neutrophils at PRE to POST 4 h tended to be lower in the M-LP than the E-FP (E-FP 38.2 ± 32.6 vs. M-LP 11.4 ± 20.6%; p = 0.050). The serum E2 and P4 concentrations were not related to serum CK at all measurement points. A significant positive correlation could be observed between the PRE serum E2 concentration and PRE lymphocyte count (r = 0.470, p < 0.05). It was unrelated after the exercise. The POST 96 h serum CK was related to the POST 96 h neutrophil count (r = 0.469, p < 0.05). CONCLUSIONS: These results suggest that MC could affect the early leukocyte reaction following eccentric exercise without influencing the serum CK.