Answer:
b. The use of protein as an energy source is greater for endurance athletes than for those who body build or lift weights.
Explanation:
Proteins are macromolecules that serves as a source of nutrients for the body. They are obtained from foods such as milk, cheese, egg, chicken, meat, legumes( Beans, lentils).
The functions of proteins include the building up of the muscular structure of the body as well as the repair of old and worn out tissues in the body.
The use of protein as an energy source is greater for endurance athletes than for those who body build or lift weights and this is because proteins when consumed and digested are broken down into amino acids which serves as a source of energy when the carbohydrate( glycogen ) stores of energy in the body are depleted due to endurance trainings of exercise.
Proteins have been found to contain Branched Chain Amino Acids which are known to be very essential and important in the repair of worn out and damage tissues during endurance trainings or exercise.
Endurance Athletes are known to have very lean muscles and Branched Chained Amino Acids help in the building up of lean muscles.