title: Assessment of Musculoskeletal Strength and Levels of Fatigue during Different Phases of Menstrual Cycle in Young Adults.
abstract: BACKGROUND
  Some of the physiological factors and athletic performance might show variation along the phases of menstrual cycle. The alterations seen in these physiological parameters of various systems relating to oscillations in hormonal levels do affect the autonomic nervous system and metabolic functions. Former studies heave inconclusively about the influence of hormones on exercise performance, predominantly muscle strength and rate of fatigue during different phases of the menstrual cycle. Studies regarding influence of these variations during bleeding phase were not done.
  
  
  OBJECTIVE
  To evaluate the muscle strength variations and also the rate of fatigue during various phases of the menstrual cycle in young adults.
  
  
  METHODS
  This was a prospective study conducted among 100 healthy adult female volunteers aged 18-24 years, with normal regular menstrual cycles persistent between 26- 32 days (average of 28 days), for a minimum of last 6 months. Muscle strength was assessed by calculating the work done and fatigue rate using Mosso's ergograph and by handgrip dynamometer strength. Each subject was evaluated consecutively for two menstrual cycles in all three phases which were classified as Phase 1- Menstrual phase, Phase 2- Follicular phase and Phase 3- Luteal phase. The data obtained was analysed by statistical tool One-way ANOVA followed by a post-hoc Tukeys test. A p-value of ≤ 0.05 was considered significant.
  
  
  RESULTS
  The amount of work done and handgrip strength was significantly higher in phase 2 (p<0.001) and relatively reduced in phase 1 and 3 (p<0.001) of menstrual cycle. In terms of fatigue rate percentage, phase 2 showed significantly lesser values (p<0.001) as compared to phase 1 and 3 of menstrual cycle.
  
  
  CONCLUSIONS
  We conclude that the cyclical variation in endogenous reproductive hormones increases the muscle strength in follicular phase of the menstrual cycle. Thus provide support for the influence of these hormones in regulation of these parameters in the premenopausal age group.
authors.affiliation: Assistant Professor, Department of Physiology, Kasturba Medical College, Manipal University , Manipal, Karnataka, India .
authors.forename: L C
authors.initials: LC
authors.lastname: Pallavi
authors.affiliation: Professor, Department of Physiology, KVG Medical College , Sullia, Dakshina Kannada, Karnataka, India .
authors.forename: Urban John
authors.initials: UJ
authors.lastname: D Souza
authors.affiliation: Associate Professor, Department of Pharmacology, Kasturba Medical College, Manipal University , Manipal, Karnataka, India .
authors.forename: G
authors.initials: G
authors.lastname: Shivaprakash
keywords: Ergograph; Exercise; Fatigue rate; Handgrip; Menstruation