MEDICINA SPORTIVA - Journal of Romanian Sports Medicine Society

Effects of menstrual period on daily energy demands in a group of elite female rowers

Introduction. The impact that the menstrual cycle phase has on the energy demands of the female athlete is now a less known topic. Often, menstrual dysfunction can be reported, through hormonal changes, associated with stress, caused by training, mentioning either volume, or intensity of the effort as influence factors.
Aim. Establishing energy requirements, along with determining the proportion of macronutrients in association with the menstruation period. Material and method. A cross-sectional study was conducted in February 2016, in Bucharest, Romania, on a group of 26 elite female rowers. The parameters analysed were related to the menstrual cycle of the athletes, in direct relationship with metabolic and respiratory parameters, determined through Cosmed Quark CPET equipment, applying the activity protocol regarding the resting metabolic rate (RMR).
Results. In the study group (20.9±2.69 years), has been determined an energy requirement equivalent to 32.1±6.13 kcal/kg/day, divided into carbohydrates (317±89.2 gr/day) and lipids (104±55.4 gr/day), representing non protein food elements. Thus, it is noted that an increase in carbohydrate consumption proportion, during rest periods (%), was associated with menstrual cycle periods (0.231±0.43) during the test. Also, lack of menstruation (0.15±0.36) was associated with increased respiratory exchange ratio (0.86±0.04), and a decrease proportion of fat consumed during rest periods.
Conclusions. Proper adaptation of the body, in different training seasons, within women athletes is directly related to energy intake, hormone levels, and recovery efficiency throughout distinct periods. Thus, various external factors will favour lack of menstrual cycle, hormonal imbalance, involving a decreased proportion of lipids used as energy source during recovery periods, increased CO2 value, along with increased respiratory exchange ratio, indicating energy metabolism inefficiency.