EHS 385 Lecture Notes - Lecture 11: Motor Neuron, Glycolysis, Maximum Force

• School: UMass Boston
• Department: Exercise and Health Science
• Course: EHS 385
• Professor: Rachel Drew

Document Summary

Chapter 8 lecture 11 oc skeletal muscle ii. Decline in muscle power output: decrease in force generation, decrease in shortening velocity. High intensity exercise (60 seconds: accumulation of lactate, h+, adp, pi, and free radicals, diminishes number of cross-bridges bound to actin. Long-duration exercise (2-4 hours: muscle factors, accumulation of free radicals, electrolyte imbalance, glycogen depletion. Skeletal: voluntary muscle, controlled consciously, over 600 throughout body. Cardiac: controls itself with assistance from nervous and endocrine systems, only in heart. Smooth: involuntary muscle, controlled unconsciously, in walls of blood vessels and internal organs. Biochemical properties: oxidative capacity: number of capillaries, mitochondria, and amount of myoglobin, type of myosin atpase isoform: speed of atp degradation, abundance of contractile protein in muscle fiber: actin/myosin. Contractile properties: maximal force production: force per unit of cross-sectional area (called specific force production, speed of contraction (maximal shortening velocity or vmax) Regulated by myosin atpase activity: maximal power output = force x shortening velocity.