Subscribe to Dr. Mirkin's free FITNESS & HEALTH NEWSLETTER
Intense Exercise for Heart Attack Patients?

Two years ago, 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 returned toward normal faster than other heart attack victims who did slower continuous training. This advantage persisted 30 months after the patients completed their 12-week rehabilitation program.

This same research group has now shown that high- intensity interval training reduces high blood pressure more than continuous exercise does (European Journal of Cardiovascular Prevention & Rehabilitation, June 8, 2011).

Researchers at the Mayo Clinic have started to supervise 30-second bursts of exercise using faster speeds and steeper inclines, gradually increasing the number of intervals and their length to 120 seconds. I believe that They are the only center in the U.S. using intense interval training to rehabilitate heart attack victims. Certainly intense training is not accepted yet 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.

This study adds to the accumulating evidence that intense exercise offers much greater health benefits than just exercising; see my summary at the end of this newsletter (below).


Reports from

Irritable bowel syndrome
Iron deficiency impairs exercise
Overtraining syndrome


Dear Dr. Mirkin: Does snacking at night make you fatter than daytime snacking?

A study presented June 14, at the 2011 annual meeting of the American Academy of Sleep Medicine and the Sleep Research Society in Minneapolis showed that people who snack at night are fatter, even though they don't eat significantly more total daily calories. Almost 40 years ago, Franz Halberg of the University of Minnesota showed that food eaten in the evening is more fattening than food eaten in the morning (1). After you eat, your body temperature rises to burn extra calories because your body has to break down the food by a series of chemical reactions that produce heat (2). After you exercise, your body temperature also rises as you supply extra calories to your muscles. When you are inactive after eating, you burn fewer calories than when you are active after eating, so eating at night is more fattening.

Mice fed only at night gained more than twice as much weight as mice that ate during the day (3). Both groups were fed the same high-fat food, and were equally active. By the end of the six-week study, night-eaters had a 48 percent increase in body weight compared to day-feeders who had a 20 percent gain.

Eating too much in the evening also increases risk for diabetes. Contracting muscles remove sugar from the bloodstream without needing insulin. Being active before eating lowers blood sugar levels the next morning (4). Exercising after eating lowers blood sugar levels after eating even more than exercising before eating (5). A large meal in the evening is often followed by going to bed or sitting around watching television, which can cause high rises in blood sugar, diabetes and cell damage. Any type of activity clears blood sugar far better than keeping your muscles still. Most people are more likely to be active in the afternoon (after lunch) than in the evening (after dinner). This suggests that you should eat your main meal mid-day and have a light supper.

1. J. Nutr 1989;119:333-43
2. Am J Clin Nutr 1993;37:476-8
3. Obesity, September 2009
4. Medicine and Science in Sports and Exercise, August 2009
5. Journal of the American Medical Directors Association, July 2009


Dear Dr. Mirkin: How can I get rid of belly fat?

Exercise and eat more soluble fiber. Researchers analyzed 1,114 black and Hispanic Americans who are at increased risk for high blood pressure and diabetes. They showed that, over five years, for every 10-gram increase in soluble fiber eaten per day, visceral fat was reduced by 3.7 percent, and that 30 minutes of vigorous exercise two to four times per week reduced belly fat by 7.4 percent over the same time (Obesity, published online June 2011). You can get 10 grams of soluble fiber in two small apples, one cup of green peas and one-half cup of pinto beans.

If you store fat primarily in your belly, you are at high risk for diabetes, heart attacks, strokes, fatty liver, high blood pressure, high cholesterol and premature death. Virtually every person who has small hips and a fat belly has very high levels of insulin because insulin causes fat to be deposited in the belly. High levels of insulin are a sign that a person's cells cannot respond to insulin. Then blood sugar levels rise even higher, which causes the pancreas to release large amounts of insulin.

Everybody needs insulin to lower high blood sugar levels by driving sugar from the bloodstream into cells. However, too much insulin can kill you. It constricts the arteries that carry blood to your heart to cause heart attacks. You can diagnose high insulin levels by getting a blood test called C-peptide. Normal values are 0.51-2.72 ng/mL or 0.17-0.90 nmol/L.

All foods that you eat contain carbohydrates, fats and protein. Carbohydrates are made of combinations of sugars as single, double, thousands and millions. Before any carbohydrate can be absorbed into your body, it must first be broken down into single sugars. Fiber cannot be absorbed in your intestinal tract because the sugar molecules are bound together so tightly that the human body cannot break them down.

Fiber is classified further into soluble and insoluble. Insoluble fiber passes from your body without being absorbed. However bacteria in the colon can break down soluble fiber into short chain fatty acids that can be absorbed. Soluble fiber is healthful because the short-chain fatty acids from it are absorbed into the bloodstream and pass to the liver where they prevent the liver from making cholesterol. Soluble fiber also helps to lower levels of a fat called triglycerides in your liver. This prevents the fatty liver that blocks insulin receptors and causes diabetes. Exercise also helps to prevent a fatty liver by preventing triglycerides from accumulating in the liver.

To get rid of belly fat, lose weight, avoid sugared drinks and foods, exercise, eat huge amounts of fruits and vegetables that are rich sources of soluble fiber, and make sure that your blood levels of vitamin D3 are above 75 nmol/L.


Recipe of the Week:

Two-Bean Cabbage Slaw

You'll find lots of recipes and helpful tips in The Good Food Book - it's FREE


Summary of studies on the benefits of intense exercise:

INTENSE EXERCISE BETTER FOR REDUCING BELLY FAT: Intense exercise is far more effective in reducing belly fat than less intense exercise (Medicine & Science in Sports & Exercise, November 2008. Metabolism 1991(May);40(5):545-551). Storing fat primarily in your belly usually means that you have very high insulin levels which increase risk for heart attacks, strokes, diabetes, metabolic syndrome and even some cancers. Insulin causes fat to be deposited in your belly.

INTENSE EXERCISE HELPS YOU LOSE WEIGHT: Many people do not lose weight when they exercise because they don't do it vigorously enough to raise their body temperatures and increase their metabolisms (International Journal of Sport Nutrition and Exercise Metabolism. January, 2001;11(1):1-14). Intense exercise can raise body temperature enough to burn extra calories for up to 18 hours afterwards (International Journal of Sport Nutrition and Exercise Metabolism, 2001;11(1):15-31). Most people cannot lose weight by swimming because water conducts heat from the body so efficiently that it prevents their body temperatures from rising.

INTENSE EXERCISE PREVENT DIABETES: Studies from Yale (Journal of Applied Physiology, January 2006) and Norway (Circulation, July 2008) show that intense exercise is far more effective in preventing and controlling diabetes than exercising at a leisurely pace. Intense exercising diabetics have lower blood sugars levels, better contraction of their arteries, better muscle growth, less cell damage, and lost more fat than casually exercising diabetics.

INTENSE EXERCISERS HAVE LONGER TELOMERES: Researchers in Homburg, Germany showed that 50-year-old men who ran more than 50 miles per week at a fast pace had telomeres (chromosome caps) that were almost the same length as those of 20-year-old runners on the German National Team, and more than 40 percent longer than those or inactive men of the same age (Circulation, December 2009). This is astounding because shortened telomeres represent aging.

The active ends of the genetic material (chromosomes) in cells are covered with a layer of proteins called telomeres. If they weren't, the exposed ends of the genetic material would stick to anything nearby and the cells would die. However, each time a cell divides to make two cells, a little bit of the telomere is removed. Eventually the telomere is gone, the ends of genetic material stick together and the cell can no longer divide so it dies without replacing itself. Obviously, the longer the telomeres, the longer it takes for the telomeres to be used up and the longer a cell lives.

INTENSE EXERCISE DOES NOT DAMAGE A HEALTHY HEART: Intense exercise does not damage a healthy heart. To improve for athletic competition, all athletes must suffer skeletal muscle damage. Without this damage, their muscles will not grow and they will not become stronger. So on one day, they exercise very intensely by lifting very heavy weights, running very fast, or competing on the basketball court very intensely. They know that they have damaged their muscles with hard exercise because their muscles feel sore on the next day. As the muscles heal, they produce growth hormones that help the muscles to grow larger and stronger.

However a normal heart cannot be damaged by 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.

July 10th, 2011
|   Share this Report!

About the Author: Gabe Mirkin, MD

Sports medicine doctor, fitness guru and long-time radio host Gabe Mirkin, M.D., brings you news and tips for your healthful lifestyle. A practicing physician for more than 50 years and a radio talk show host for 25 years, Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. He is board-certified in four specialties: Sports Medicine, Allergy and Immunology, Pediatrics and Pediatric Immunology. The Dr. Mirkin Show, his call-in show on fitness and health, was syndicated in more than 120 cities. Read More
Copyright 2016 Drmirkin | All Rights Reserved | Powered by Xindesigns