Sudden vigorous exercise without warm-up in healthy men caused ischemic ECG changes in 3 of 10 subjects and minor ST abnormalities in 3, which were prevented by prior warm-up exercise.
Observational (n=10)
Does sudden vigorous exercise without warm-up induce ischemic electrocardiographic changes in healthy men compared to exercise with warm-up?
Sudden vigorous exercise without warm-up can cause transient subendocardial ischemia in healthy men, which is prevented by prior warm-up.
In ten healthy, asymptomatic men, intra-arterial pressure and electrocardiograms were recorded during various types of exercise. Potential subendocardial blood flow was estimated from a diastolic pressure time index (DPTI) and myocardial oxygen requirements estimated from the tension time index (TTI). The ratio DPTI/TTI provided an estimate of the supply/demand relationship With sudden vigorous exercise without warm-up, the DPTI/TTI was below 0.35 in three men who had ischemic electrocardiograms, below 0.44 in three men with minor ST abnormalities, and above 0.44 in four men with normal ST segments. With a prior warm-up exercise, sudden exercise caused no ischemic changes, but DPTI/TTI was below 0.44 in two subjects who had minor ST abnormalities. Maximum treadmill testing produced higher heart rates and TTI than did sudden exercise, but DPTI/TTI was above 0.44 in all cases and no ST abnormalities occurred. Abnormal electrocardiographic responses produced by sudden, vigorous exercise in normal men may represent subendocardial ischemia caused by a transient, unfavorable alteration in the subendocardial oxygen supply/demand relationship which is predictable from arterial pressure measurements.
Barnard et al. (Thu,) conducted a observational in Healthy, asymptomatic men (n=10). Sudden strenuous exercise without warm-up vs. Prior warm-up exercise and maximum treadmill testing was evaluated on Ischemic electrocardiographic changes and DPTI/TTI ratio. Sudden vigorous exercise without warm-up in healthy men caused ischemic ECG changes in 3 of 10 subjects and minor ST abnormalities in 3, which were prevented by prior warm-up exercise.