Intermittent high intensity physical training and plasma lipoprotein lipid levels in men

Levels of plasma lipoprotein lipids and anthropometric and physical fitness measurements were followed in 12 normal men over a 16 month period including training for two marathon runs separated by one year. As judged from pulse rate at submaximal work, the physical fitness of the men increased during training for the marathons and also over the whole study. High density lipoprotein (HDL) cholesterol levels which had been raised by training for the first marathon, were at similar levels at peak training prior to the second marathon. Estimated alcohol consumption was significantly higher prior to marathon II compared to the level prior to marathon I but this did not result in increased plasma high density lipoprotein cholesterol levels. The trend towards increased low density lipoprotein (LDL) cholesterol levels early in the study continued until the levels were finally significantly higher than pretraining values. It is possible that plasma high density lipoprotein cholesterol levels in the men reached personal maximum levels after training for the first marathon and were unaffected by an apparent increase in aerobic fitness achieved after training for the second marathon. This study also indicated that the effects of long term training on plasma lipids and lipoproteins may differ from those observed following shorter periods of exercise.