Basal Metabolic Rate

(BMR)

- Basal Metabolic Rate, Physical Activity, Thermic effect of food 

- lean body mass

- diet, age, gender, genetics, and hormone levels

- exercise duration

- exercise intensity

- antecedent diet

- training status

* substrat contribution comes from carbs, proteins and fat

Respiratory Exchange Ratio (RER)

- CO2 produced/O2 consumed

- RER for carb = 1

- RER for fat = .7

- RER for protein = .82

- during exercise glycogen stores become progressively depleted, increasing fat use for energy

- as duration increases, RER decreases; suggesting more fat is being used to fuel

- increased use of fat relates to decreases in insulin which is an inhibitor of lipolysis

- as exercise intensity increases, RER increases suggesting a higher % of carbs are being used to fuel

- more fat is still being burned just not more as a percentage

- rest is considered to be the lowest intensity and therefore shows the GREATEST % of fat use but not the MOST total fat use

- in order to burn more fat during aerobic exercise, limit carb intake prior to exercise

- longer fasted, less carb is burned for fuel (<fat)

Training and oxidizing fat

- trained individuals oxidize proportionally more fat and less carbs than untrained individuals

-following training, the body becomes more efficient at utilizing fat as an energy source both during and following exercise

Excess Post-Exercise Consumption

(EPOC)

- after exercise, it takes time for the body's metabolic rate to return to resting levels; therefore the body is still consuming an elevated amount of oxygen

-all tissues that are helping meet the demands of increased muscular activity also increase their own need for O2 during recovery to reestablish homeostasis

- higher the intensity, greater the EPOC