Serum Creatine Kinase Increases after Acute Strength Training in College Athletes with Menstrual Irregularities

Akemi Sawai,Yuki Warashina,Risa Mitsuhashi,Alexander Zaboronok,Bryan J Mathis

doi:10.3390/women1020007

Abstract

Chronic menstrual dysfunction and low female sex hormones adversely affect muscular performance in women but studies in college athletes are scarce. A cohort of 18 Japanese, female college athletes at the University of Tsukuba, Japan, were recruited and studied over 3 weeks under 2 conditions. One group had normal menstrual cycling (CYC, 9 athletes) while the other had irregular cycles (DYS, 9 athletes). Hormones and creatine kinase (CK) were measured from blood under both rest (RE) and exercise (EX) conditions. Biceps femoris tendon stiffness was measured by myometry. No differences in age, height, weight, menarche age, or one-repetition maximum weight existed between the groups. The DYS group had persistently low levels of estrogen and progesterone. In the CYC group, the CK level significantly increased at each point immediately post-exercise and 24 h post-exercise compared to pre-exercise in Weeks 1 and 2, and significantly increased at 24 h post-exercise compared to pre-exercise status in Week 3. The DYS group was significantly different only between pre-exercise and 24 h post-exercise over all 3 weeks. The DYS group also suffered from higher biceps femoris tendon stiffness at 24 h post-exercise. Chronic menstrual irregularities in Japanese college athletes increase muscle damage markers in the bloodstream and muscle stiffness after acute strength training.

Highlights

Published: 9 April 2021Resistance training enhances muscle function, controls muscular glucose metabolism, and contributes to stabilization that reduces musculoskeletal injury [1]
Around 33% of Japanese college athletes suffer from menstrual dysfunction and this issue globally affects female athletes [8,9]
Women are prone to hamstring injury, and resistance training the biceps femoris to prevent injury is a key component of female sports conditioning [10,11], but this muscle accounts for high creatine phosphokinase activity after exercise [12]

Summary

Introduction

Resistance training enhances muscle function, controls muscular glucose metabolism, and contributes to stabilization that reduces musculoskeletal injury [1]. It requires efficient repair of muscles after Type I injury (muscle soreness that occurs 24 to 48 h after unaccustomed exercise, known as delayed onset muscle soreness, “DOMS”) for full recovery and subsequent increases in strength [2]. Low female sex hormones result in poor exercise recovery and, in women with oligomenorrhea, may decrease the advantages of acute strength training due to inefficient repair [4]. Creatine kinase (CK), released into the blood from damaged muscle tissue, is a useful biomarker for the intensity of a strength exercise while musculoskeletal stiffness during recovery, especially in the Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations

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Discussion

Conclusion