List and briefly discuss three factors that increase the basal metabolic rate. Then list and briefly discuss three factors that decrease the metabolic rate.

Question

What will be an ideal response?

Answer 1

The following factors increase the metabolic rate:
?••• Growth: In children, adolescents, and pregnant women, the BMR is higher.
?••• Height: In tall, thin people, the BMR is higher.
?••• Body composition (gender): The more lean tissue, the higher the BMR (which is why males usually have a higher BMR than females).
?••• Fever: Fever raises the BMR.
?••• Environmental temperature: Both heat and cold raise the BMR.
?••• Hormones (gender): The thyroid hormone thyroxine, for example, can speed up or slow down the BMR. Premenstrual hormones slightly raise the BMR.
?••• Smoking: Nicotine increases energy expenditure.
?••• Caffeine: Caffeine increases energy expenditure.

The following factors decrease the metabolic rate:
?••• Age: Lean body mass diminishes with age, slowing the BMR.
?••• Body composition (gender): The more fat tissue, the lower the BMR (typically women).
?••• Stresses: Stresses (including many diseases and certain drugs) raise the BMR.
?••• Fasting/starvation: Fasting/starvation lowers the BMR.
?••• Malnutrition: Malnutrition lowers the BMR.
?••• Hormones (gender): The thyroid hormone thyroxine, for example, can speed up or slow down the BMR.
• Sleep: BMR is lowest when sleeping.