Garment factories in India is the second largest sector for employment, approximately 60% of the population employed in the garment industry are women. Menstrual cycle is a physiological phenomenon during reproductive life of women. Its phases are influenced by alteration in the concentration of hormones such as estrogen and progesterone. Fluctuating levels of sex steroids across normal menstrual cycle affect sensory- motor association of an individual. So this study was done to assess the muscle performance capability in terms of hand grip strength (strength of upper limb muscles) as Maximum Voluntary Contraction (MVC) and time for fatigue at 30% of MVC during Menstrual, Proliferative and Secretory Phase of menstrual cycle among 54 garment workers. Maximum voluntary contraction was higher during secretory phase than proliferative and menstrual phase. And time to fatigue at 30% MVC was also found to be higher during secretory and proliferative phase compared to menstrual phase. Overall muscle performance capability was found to be better during secretory phase of menstrual cycle, may be due to increased blood flow to the muscle and glycogen storage under the influence of estrogen and progesterone. Estimation of female sex hormones during different phases and its correlation to muscle performance may reveal more facts.