After exercise, consuming carbohydrates raises UDP-GlcNAc levels in rat muscle tissue, which may be involved in restoring normal insulin response following physical activity.

In rats, after exercise and eating carbohydrates, the hexosamine biosynthetic pathway is the most likely biological mechanism responsible for restoring normal insulin sensitivity, based on increased levels of its metabolic products and known connections to insulin resistance; other pathways have not been supported by evidence.

When muscle that has recently been exercised is exposed to high levels of glucose and insulin in a controlled lab environment, its ability to take up glucose in response to insulin is reduced, suggesting that nutrients present after exercise can directly reduce insulin sensitivity without involving glycogen stores or whole-body signals.

In rats, after exercise improves insulin sensitivity and then carbohydrates are reintroduced, the loss of this improvement happens even when the body cannot store extra glycogen in muscles, suggesting another metabolic process is responsible.

Eating a meal high in carbohydrates before doing cardio exercise increases how effectively insulin promotes the building of muscle and fat tissue in the body.

In male rats, eating a high-carbohydrate meal within 48 hours after endurance exercise reduces the muscle's ability to take up glucose in response to insulin, compared to not eating carbohydrates after exercise. This suggests the timing of carbohydrate intake after exercise affects how the body uses glucose.