Physiology

• VO2 max increases with endurance training for only 8-12 weeks and then plateaus
• Increased training means athlete can perform at a higher percentage of VO2 max
• VO2 is expressed relative to body weight 
• Age decreases about 1% each year from 25-30yr from a combination of aging and sedentary lifestyle 
• Men have larger VO2 max as: larger hearts, more fat-free mass, and higher blood haemoglobin content so higher O2 carrying capacity
• Heredity accounts for 25-50% of variance

Criterea 

• Plateau 
• RER >1.1
• Max HR within 10bpm of age estimated HR
• Blood Lactate >8-10mmol/L