1. Metabolic Rate Fitness Efficiency
Human Metabolism
Metabolic Rate
Fitness
Efficiency

2. Metabolism Internal energy comes from food
Oxidation of food supplies energy
Energy goes into
Internal functions
External work
Excess expelled as heat
Rewrite in terms of rates
U/t < 0
Must replenish U with food
The metabolic rate (U/t) is the rate at which food and oxygen are converted to internal energy to balance loss through Q & W

3. Metabolic Rate
Metabolic Rate directly proportional to volume of oxygen consumed
U/t in kcal/s
VO2/t in L/s
Can measure VO2/t to determine metabolic rate
Can measure W/t to determine power output
Use to find efficiency

4. Basal metabolic rate is the rate when sleeping
Metabolic Rates
p. 415
Basal metabolic rate is the rate when sleeping

5. Physical (“Aerobic”) Fitness
Aerobic fitness is a measure of a person’s maximum capacity to use oxygen
Increases with exercise
Decreases without
p. 416

6. Efficiency Body does work  can function as a machine
Define efficiency as before
Affected by the type of work done
p. 416