US doctors write exercise prescription to help heart

IF your New Year resolution to exercise and get fit has already fallen by the wayside‚ a team of US cardiologists can help.

They have an exercise “prescription” which reverses damage to ageing hearts.

“Based on a series of studies performed by our team over the past five years‚ this dose of exercise has become my prescription for life‚” Benjamin Levine, director of the Institute for Exercise and Environmental Medicine at the University of Texas, said.

The regimen involves exercising four to five times a week‚ generally in 30-minute sessions‚ plus time to warm up and cool down.

ý One session is a high-intensity 30-minute workout‚ like aerobic interval sessions in which your heart rate tops a peak rate of 95% for four minutes‚ with three minutes of recovery‚ repeated four times;

ý Each interval is followed by a recovery session at a relatively low intensity;

ý One day session of an hour of moderate intensity. Levine said it could be tennis‚ aerobic dancing‚ walking or cycling;

ý One or two other sessions a week at a moderate intensity‚ meaning you need to sweat a little and be a bit short of breath; and

ý One or two weekly strength-training sessions with weights or any exercise apparatus on a separate day‚ or after a bout of endurance.

Study participants built up to those levels‚ beginning with three‚ 30-minute‚ moderate exercise sessions for the first three months and peaking at 10 months when two high-intensity aerobic intervals were added.

The 50-plus participants‚ aged between 45 and 64‚ were divided into two groups.

One received two years of supervised exercise training and the other participated in yoga and balance training.

At the end of the two-year study‚ those who had exercised showed an 18% improvement in their maximum oxygen intake during exercise and a more than 25% improvement in elasticity of the left ventricular muscle of the heart.

Levine compared the change in the heart to a stretchy‚ new rubber band versus one that has become stiff while in a drawer.

Sedentary ageing can lead to a stiffening of the muscle in the left ventricle‚ the chamber that pumps oxygen-rich blood back out to the body‚ he said.