Acute effects of short duration maximal endurance exercise on lipid, phospholipid and lipoprotein levels.

AIM: The acute effects of maximal endurance exercise (15 min) on lipid and lipoprotein levels were examined, in order to determine whether the level of response produced could be affected by maximal exercise intensity (incremental stress test). METHODS: Participants in this cross sectional study were male athletes (n=78) of national level: basketball (n=10), swimming (n=9), long distance (LD) running (n=23) and wrestling (n=35); also a group of non-athlete volunteers as controls (n=19). Athletes had trained an average of 3 h/day and 5 years. The ergometric test used for the determination of maximal oxygen uptake on a treadmill was based on a stepwise stress protocol. RESULTS: Immediately after a maximal effort all groups (controls included) showed significant increases in total cholesterol (TC), triglycerides (TG), phospholipids (PL) and high-density cholesterol (HDL-C), from rest values. Low-density cholesterol (LDL-C) increased significantly in basketball, LD running and wrestling, while it did not change significantly in swimming and controls, after maximal effort. Hemoconcentration was of the order of +12.5%. CONCLUSIONS: The level of these increases might be directly related to the intensity and duration of exercise performed. Acute endurance exercise (100% VO(2max)) may induce acute modification of the above lipid parameters potentiating the systematic chronic exercise effects already present.

Comparison of respiratory response of jogging in place and Bruce treadmill exercise test.

A comparison of the respiratory responses of jogging in place, an alternative exercise test we recently proposed, was made with those of the Bruce exercise test. We obtained on-line measurements of heart rate, ventilation, oxygen uptake, and carbon dioxide production from 9 healthy subjects of mean age 25 years. There was a higher heart rate and ventilatory response with jogging than with the Bruce test, but by 10 minutes the responses of the two tests were similar. Oxygen consumption, while higher with jogging, rose in parallel with that of the Bruce test from the second to the seventh min, and the change of the ratio of minute ventilation to oxygen consumption indicated that the anaerobic threshold occurred earlier during jogging. These results show that jogging in place is more vigorous than the graded exercise test and may produce ischemia earlier.