Timing of Weight Loss Efforts Matters

Exercise first then diet prevented muscle loss in people with metabolic syndrome

(RxWiki News) Diet and exercise are often recommended for weight loss. For people to get the most from their weight loss efforts, the order in which they diet and exercise may matter.

Muscle loss often occurs during dieting, particularly in people with metabolic syndromeMetabolic syndrome is a group of symptoms that include a large waistline, high levels of fat in the blood, high blood sugar and high blood pressure — all of which can raise the risk of heart disease, diabetes and stroke.

Weight loss from dieting doesn’t always last, and repeated weight loss can mean more muscle loss.

Recent research found that people with metabolic syndrome who exercised before they started a weight loss program lost less muscle mass.

"Talk to your doctor before starting an exercise program."

The lead author of this study was Yonit Marcus, MD, PhD, an endocrinologist at the Institute of Endocrinology, Metabolism and Hypertension of Tel Aviv Medical Center in Tel Aviv, Israel.

The research team recruited 38 men and women with metabolic syndrome into their study. The patients ranged in age from 19 to 71 years old. The median (middle) age of the group was 53 years old.

The study lasted one year, during which the participants were part of an intensive weight loss program that included help from doctors, a dietician and a physiologist (body function or exercise specialist).

At the beginning and the end of the study, the researchers used a measurement called a DEXA scan to determine body composition.

Results of the study showed that both men and women lost weight and body fat. Younger patients lost more weight and more body fat than older patients.

Patients older than 53 years old lost about 6 percent of their body weight.

Women under the age of 53 lost 11 percent of their body weight and men under age 53 lost 10 percent of their weight.

Men and women under the age of 53 lost about 17 percent of their body fat. Men over the age of 53 lost 15 percent of their body fat and women over the age of 53 lost 10 percent.

When the researchers analyzed the amount of weight loss that represented lean mass (not fat but including muscle), they found that men under age 53 lost 1 percent of their lean mass.

Women under the age of 53 lost 5 percent of their lean mass. Men and women over the age of 53 lost about 3 percent of their lean mass.

The authors of the study reported that patients who gained or lost less than 2.9 percent of their lean mass were those who were already performing physical activity before they started the study and continued the activity for the year of the study.

“During intensive weight-loss supervised by a multidisciplinary team according to current ‘best practice’ guidelines: a) young and older men can lose weight without obligatory lean mass loss; b) young and older women tend to lose lean mass (muscle), along with fat loss, unless they engaged in physical activity prior to the attempted weight loss," the authors concluded.

“The metabolic syndrome and obesity have become the pandemic of the 21st century and the only measures taken to counter this problem are exercise and diet. Exercise and diet are commonly started at the same time, but this should be reconsidered,” Dr. Marcus said in a press statement.

This research was presented June 22 at the joint meeting of the International Society of Endocrinology and the Endocrine Society, ICE/ENDO 2014, held in Chicago, Illinois.

Funding for the study was provided by the Sami Sagol Foundation.

Review Date: 
June 25, 2014