Comparison of the Acute Effect of Single Session of Submaximal Exercise in Hot and Cold Ambient Temperatures on Lipid Profile

Introduction: Coronary artery disease (CAD) is the most important clinical manifestation of atherosclerosis1. A positive correlation exists between serum cholesterol and the risk of coronary heart disease and a negative correlation with high density lipoprotein cholesterol (HDL-C).2, 3 Physical exercise in both hot and cold causes acute changes in serum lipid profile.

Aims & objective: The present study was aimed to compare the effects of single session of low intensity sub maximal exercise, in cold and hot ambient temperatures on Serum Lipid profile.

Materia & Materials: 10 healthy university students (age 24.1±0.9, weight 65.1±7.6) participated in the randomized, repeated measure, experimental study. Subjects performed submaximal cycling exercise at 45-55% heart rate reserve (Karvonen Method)4 at ambient temperatures of 20 ±1ºC (cold) and 42 ±1ºC (hot), on static bicycle for 30 minutes. Blood samples were drawn at 10 minutes pre, 10-15 minutes and 24 hours post submaximal exercise and results were observed for changes in lipid profile.

Results & Analysis: There was a significant increase of 35.66% and 38.89% and of 20.8% and 23.07% in HDL-C for post 10 min and 24 hour respectively following exercise in hot and cold temperature respectively. Significant increase of 7.6% and 8.2% was observed for post 10 minute and 24 hour respectively following exercise in hot temperature only in Total cholesterol. Significant increase of 10.8% in Triglyceride concentration post 10 minute exercise exposure in cold with non significant changes following exposure in hot environment.

Conclusion: Exercise in moderately hot temperature more effectively alters lipid profile than exercise in moderately cold temperature.