UNIVERSITY Passive Recovery: Sleep How to Improve Sleep For Recovery Lesson Overview • What is sleep and why we need it • Effects of sleep deprivation on performance • How to Improve Sleep What is Sleep? The physiological process where metabolic and other regulatory functions halt for a period of time so that the body systems recover and prepare the next day’s functional needs (1) Sleep Stages (90-120 minute cycles) 4-6x per night • Rapid Eye Movement (REM): dream and memory consolidation • Slow Wave (nonREM): Slowing of body function, most restful sleep Sleep Mechanisms: regulate awake and sleep • Circadian (biological clock) rhythm: Based on 24-hour day, controls sleep, hormone release, body temperature • Sleep-wake homeostasis: Tracks need for sleep Influenced by stress, nutrition, exercise, medications What Does it Do? • Restore Immunological and endocrine balance • Increase parasympathetic activity • Recovery of nervous system and metabolic systems • Enhance memory consolidation and learning • Growth hormone release and Tissue repair Effects of Sleep Deprivation Sleep Deprivation • • • • • • • • • • Altered glycemic control and decreased insulin sensitivity (4) Decreased Leptin and Increased Ghrelin (1) Reduced Oxygen Consumption and Cardiovascular Performance Reduced Motor Learning and Control Reduced Growth Hormone and Testosterone Levels Lower Lymphocyte and antibody levels Decreased mood, motivation, perception of fatigue Increase in Recurrent Injuries and slowed injury repair Highly Associated with overtraining nights of 50% sleep reduction decrease muscle protein synthesis (2) • During caloric restriction, sleep loss increased muscle loss and decreased fat loss (3) • CONTEST PREP: Muscle Fat • OFFSEASON: Muscle Fat Optimal Sleep Durations • • • • Recreational Athletes: 7-8 hours per night Advanced Athletes: 8-10 hours per night Sleep and mortality relation is a U-shaped curve Too much sleep can result in increased drowsiness and fatigue and increased association of all cause mortality and CVD (5) • Too little sleep