Chapter 22, Problem 20P

Interpretation Introduction

Interpretation:

Using the graph in Deeper Look box, the timing of the provision of energy from different metabolic sources during heavy exercises should be explained.

Concept Introduction:

During rest and normal activities, 80 to 90 % energy is contributed by fats, 5 to 18 % from carbohydrates and 2 to 5 % from protein. In exercise, there are total four main endogenous sources of the energy: intramuscular triacylglycerols, glycogen (muscle carbohydrate stores), blood fatty acids, and blood sugar.