Pancreatic polypeptide response to exercise. Effect of alanine and glucose ingestion in carbohydrate-starved athletes.

Human pancreatic polypeptide (hPP) secretion in response to 90 minutes of exercise before and after the ingestion of 50 g glucose or 50 g L-alanine in 33 carbohydrate-starved athletes was examined. There was a very marked increase in plasma hPP concentration with exercise under these circumstances, despite previous reports that the hPP response to exercise is eliminated by training. Glucose and alanine ingestion had no effect on hPP either before or after exercise. This differentiates hPP from other hormones in which secretion is increased by exercise in carbohydrate-depleted subjects.