Effects of Sleep Restriction on Female Soccer Players: Physical Performance, Muscle Damage, Inflammation, and BDNF Levels.

This research aims to investigate the interplay between menstrual cycles, sleep patterns, and athletic performance. Before experimental sessions, participants will maintain menstrual diaries for three months and complete assessments for sleep disorders and chronotype. Sleep duration will be objectively measured over five nights using actigraphy, complemented by sleep-related data from an actigraph and the Karolinska Sleep Diary. The study involves two sessions: normal sleep (based on habitual duration) and restricted sleep (reduced by 3 hours). Athletes will engage in a simulated match-play game before both sessions, followed by comprehensive performance tests the next day. Blood samples will be collected at three intervals to analyze hormonal profiles (including progesterone, and estradiol), markers of muscle damage, inflammation, stress (such as TNF-α, IL-6, CRP, myoglobin, cortisol, testosterone), and brain-derived neurotrophic factor (BDNF). On Day 1, pre- and post-training blood samples will be obtained, and participants will wear an actigraph, adhere to specified bedtime routines, and report activities (restricted sleep group). Day 2 involves completing a sleep diary, refraining from caffeine, responding to questionnaires assessing readiness to train and mood, and undergoing performance tests followed by self-reporting of pain levels and perceived exertion using established scales (VAS, RPE 6-20).