Exercise‐Induced Transient Hyperlipidemia in the Racehorse

Abstract

Effects of graded intensity exercise on plasma lipids was studied in Standardbred and Finnishbred Trotters. The rate of lipolysis indicated by the elevated plasma concentrations of glycerol increased parallel with the intensity of the trot in the Standardbreds, but not as clearly in the Finnishbred trotters. During the exercise plasma triglyceride concentration increased significantly and the increase correlated with the intensity of the exercise as well as the activity of lipolysis. Together with the increase in plasma triglycerides, there was a parallel increase in the pre-beta fraction of lipoproteins which suggests that the hepatic synthesis of triglycerides was increased. It was calculated that about one third of the nonesterified fatty acids released in lipolysis during the high-intensity exercise is oxidized and the remainder is used for resynthesis of triglycerides. Since there were interstrain differences in the concentrations of triglycerides and glycerol after the high-intensity exercise it is suggested that the differences may be of some value in the estimation of recovery after submaximal exercise.