Maintaining adequate glycogen stores primarily affects energy use by sparing which resource?

Maintaining adequate glycogen stores primarily affects energy use by sparing which resource?

• A. Spares use of protein for energy
• B. Improves maximum power
• C. Decreases endurance performance
• D. Helps athletes gain weight

Answer: (A)

Maintaining adequate glycogen stores keeps carbohydrate fuel readily available for energy production during exercise, so the body can rely on carbohydrate oxidation rather than breaking down muscle protein for energy. When glycogen runs low, amino acids are diverted into gluconeogenesis to maintain blood glucose, leading to greater proteolysis. So keeping glycogen stores high primarily spares protein from being used as an energy source. The other options don’t align with this mechanism: maximum power depends on immediate energy systems; endurance is typically improved by adequate glycogen and is not decreased by it; and glycogen levels don’t directly cause weight gain.

Maintaining adequate glycogen stores keeps carbohydrate fuel readily available for energy production during exercise, so the body can rely on carbohydrate oxidation rather than breaking down muscle protein for energy. When glycogen runs low, amino acids are diverted into gluconeogenesis to maintain blood glucose, leading to greater proteolysis. So keeping glycogen stores high primarily spares protein from being used as an energy source. The other options don’t align with this mechanism: maximum power depends on immediate energy systems; endurance is typically improved by adequate glycogen and is not decreased by it; and glycogen levels don’t directly cause weight gain.