Just One Day of Exercise Protects the Heart
By Gabe Mirkin MD, September 26, 2011
“JUST ONE DAY OF EXERCISE CAN PROTECT THE HEART AGAINST…(A HEART ATTACK)…. and this protection is upheld with months of exercise, making exercise one of the few sustainable preconditioning stimuli” (Journal of Applied Physiology, September 2011). Wow.
HEART ATTACKS OCCUR WHEN A PLAQUE SUDDENLY BREAKS OFF FROM THE WALLS OF AN ARTERY SUPPLYING BLOOD TO THE HEART. The plaque travels down the ever-narrowing artery until it completely blocks the flow of blood to a part of the heart’s muscle. The heart’s muscle must receive oxygen from the bloodstream all the time. When a part of the heart muscle is suddenly deprived of oxygen, it dies and you suffer a heart attack. The dying heart muscle usually causes severe pain, in the chest, back or left arm. Heart attacks are not caused by progressive narrowing of an artery.
LACK OF OXYGEN IS THE ULTIMATE CAUSE OF HEART MUSCLE DAMAGE. Anything that increases the ability of the heart muscle to survive oxygen deprivation or increases oxygen supply to the heart muscle helps to prevent heart attacks.
Exercise helps to prevent heart attacks, and the more intensely you exercise, the greater the protection. Researchers in Norway treated recovering heart attack victims with the same intense training methods used by competitive athletes (American Heart Journal, June 2009). They supervised them as they ran on a treadmill very fast for a few seconds, rested and then repeated their intense intervals. For example, some of the patients ran fast for 30 seconds every five minutes. The interval-training heart attack victims were able to use more oxygen maximally (VO2max) and had their heart rates return toward normal faster than other heart attack victims who did slower continuous training. This advantage persisted for 30 months after the patients completed their 12-week rehabilitation program.
INTENSE TRAINING IS NOT ACCEPTED AS A TREATMENT FOR HEART ATTACK VICTIMS, particularly those who have chest pain with exercise or excessive shortness of breath. Intense exercise can precipitate heart attacks in people with blocked arteries. The exercise sessions are usually supervised by trained technicians using electrocardiograms, at least in the beginning.
INTENSE EXERCISE DOES NOT DAMAGE HEALTHY HEARTS. All known tests for heart function show no damage from intense exercise. Post-exercise electrocardiograms and echocardiograms are normal, as are blood levels of heart-specific enzymes, creatine kinase and creatine kinase MB, and myoglobin (Medicine and Science in Sports and Exercise, October 2003).
A WORD OF CAUTION: Before you start a program of cycling, running, tennis or anything else, realize that exercising intensely is far more likely to cause injuries and can cause heart attacks in people with blocked arteries leading to their hearts. You may want to check with your doctor before you start. Then get in shape gradually by exercising at an easy pace three to six days a week for at least six weeks.