Weight Lifting And Metabolic Rate

The Study
Ninety four women were put on an 800 calorie per day weight loss diet and placed into one of 3 intervention groups: 1) Aerobic training 3 days per week for 40 minutes, 2) Resistance training 3 times per week, or 3) A control group. Fat free mass and resting energy expenditure were measured both before and after the intervention. Fat free mass is basically your muscle mass, and resting energy expenditure is the amount of calories each day your body needs to perform basic functions.  

At the end of the 6 month follow up, all of the women lost similar amounts of weight. However, the resistance training group maintained muscle mass during the weight loss period, while the aerobic exercise group and the control group lost muscle mass while losing weight. Consequently, the resistance training group had a much lower drop in resting energy expenditure after weight loss (44 calories per day) compared to the aerobic group (76 calories per day) and the control group (103 calories per day). Obesity 2008; 16:1045-51

Take Home Message

The majority of people who lose weight, eventually gain it back. A drop in resting energy expenditure is a big reason why this is the case. This study shows that a reduction in muscle mass is very likely the culprit. Muscle is a very active tissue. Each pound burns roughly 50 calories each day, whether you exercise or not. When you lose weight without weight lifting, a lot of the weight you lose is muscle and your metabolism drops. When you lift weights, you maintain the muscle and your metabolism drops much less, making it easier to keep the weight off.

If long term weight management is your goal, it is essential to hit the weights at least twice per week. You don’t need to spend hours in the gym to do this. Just do one exercise for each of the major body parts: your chest, back, shoulders, biceps, triceps, abs, and legs. The whole routine should take about 20 minutes and you can do it at home. All you need is an exercise mat and some dumbbells. Resistance training absolutely has to happen if you want to keep the weight off long term. In my opinion, it is the most overlooked aspect of weight loss programs.