Exercise beneficial - even without weight loss - in treatment for obesity: report

Exercise can cut the risk of heart disease, high blood pressure, diabetes and premature death, even if the bathroom scale stubbornly refuses to budge, according to a review of recent research published today in the journal Applied Physiology, Nutrition, and Metabolism.

In Canada's continuing "battle of the bulge", the casualties are rising. Approximately 30% of Canadians could be classified as obese-an alarming number when you think about the increased risk of serious disease associated with high body fat.

However, this new report indicates that increased physical activity - even without a reduced-calorie diet - cut the risk of obesity-related illnesses, even if obese patients did not lose much weight.

The key, believe researchers Peter M. Janiszewski and Dr. Robert Ross, of Queen's University in Kingston, Ontario, is excess belly, liver and muscle fat. Fat in these areas is linked to heart disease, high blood pressure, diabetes and premature death. In a review of previous studies in which obese patients were prescribed increased physical activity without a reduced-calorie diet, they found that belly fat and waist circumference decreased even if overall weight did not change.

These previous studies indicate that physical activity is important in reducing abdominal fat storage, and that an increase of 45-60 min/day is required to see effective, positive change. This is important for health care practitioners to remember when treating obese patients who seem resistant to weight loss, despite increased exercise. Patients could start to feel like they are making less progress when their bathroom scales are no longer moving. Ross and Janiszewski instead suggest relying on a tape measure to regularly check waist circumference to gauge success. It is important for healthcare practitioners to counsel these patients effectively so that they realize that, although they may not be losing weight, they are still increasing their quality of life and decreasing their risk for an early death.

For more information, see the complete article "Physical Activity in the Treatment of Obesity: Beyond Body Weight Reduction," Applied Physiology, Nutrition, and Metabolism, June 2007, at http://apnm.nrc.ca/obesitytreatment.

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