Exercise Alongside Restraint in Food Intake Equal Weight Loss

"During moderate weight loss, for example, five percent of initial body weight, the associated loss of visceral adipose tissue has been estimated at 21 percent in response to exercise and 13 percent in response to diet." 

French researchers

A French research team in the interests of casting light on exercise as a weight-loss tool, set out to review and summarize findings of 149 high-quality studies assessing physical activity effects on weight loss, fat loss, visceral fat loss, body composition and weight maintenance. The studies included in the review focused on either aerobic training, resistance training or high intensity interval training (HIIT) and making a comparison between exercise to a non-exercise control group or the inclusion of another intervention type, such as diet.

The purpose was to report on their findings in relation to either weight loss, fat loss, lean mass (muscle) loss, or weight maintenance. The studies under review had been published between 2010 and 2019, including in their focus overweight or obese adults. The results indicated regardless of the type of training, exercisers experienced a 1.5 to 3.5 kilogram greater weight loss than non-exercisers. A recognizable trend toward greater weight loss of about one kilogram was recognized, when exercise and diet were combined as opposed to dieting alone.

In making a comparison between one type of exercise as opposed to another, aerobic exercise was seen to outperform resistance exercise in most of the studies; a kilogram more weight and fat were lost in each instance. In comparing HIIT to moderate intensity aerobic exercise, high intensity interval training, saw greater weight loss when energy expenditure between the two exercise forms was matched. Without matching energy expenditure moderate intensity exercise burned more weight, but not significantly more.

Decreasing belly fat located around internal organs responded to all forms of aerobic exercise and aerobic exercise in combination with resistance training, resulting in a useful reduction of visceral fat. Resistance exercise on its own failed to exert the same effect on reducing visceral fat. What was clarified is that visceral fat stores are amenable to significant reduction even when weight loss fails to occur; exercise beats diet alone in losing deep belly fat.

Weight training was flagged as superior in stimulating muscle growth and the maintenance of increase of lean body mass. Resistance exercises were acknowledged as the most successful at reducing the loss of lean body mass. No evidence was seen that more intensive exercise is superior to moderate levels of physical activity in keeping lost weight off. Results which fall in line with other recent studies suggesting the importance of exercise in weight maintenance. 

The results confirm the advice of experts recommending regular exercise while at the same time corroborating the caution against investing all weight-loss efforts into exercise alone. Any type of aerobic exercise outperforms resistance training or diet alone in weight loss; resistance training is superior at maintaining muscle mass. 

Overall health can be improved, alongside greater longevity with even judiciously modest amounts of weight loss, giving value to exercise beyond what a weight scale informs. In long-term weight loss, maximizing results rests in combining regular aerobic exercise with dietary amendments alongside sufficient sleep and stress management in one's daily routine.