A popular idea in fitness is that dieting slows your metabolism because of something called “starvation mode”. The good news is that starvation mode does not exist. However, the bad news is that dieting (dropping your calorie intake to lose weight) does slow your metabolism, and understanding the actual reason why this happens is crucial for your long term success…
Weight Loss vs. Fat Loss
Even with sufficient protein intake, when you lose weight by cutting calories most what you lose is lean body mass (not fat). When the weight is regained it returns as disproportionately fat. In other words, each diet cycle (even at the same weight) leaves you with more fat and less muscle.
The more muscle you lose the lower your metabolic rate, and the fewer calories you burn during any kind of activity. This makes every diet you do progressively less effective.
Enter Strength Training
Strength training is the most important exercise to do during weight loss. This is true if you want to
- focus on losing body-fat
- avoid metabolic slow down
- set yourself up for life-long success
- have “tone”
- have a high quality of life now and in the future (those children, grandchildren, nieces, nephews aren’t going to pick themselves up!)
- avoid osteoporosis
While you must be in a calorie deficit to lose weight, it is important to remember than when we say, “I want to lose weight” what we really mean is, “I want to lose body fat because I want to feel better, fit back into my clothes again, be healthier… and I want to keep it off.” There’s a world of difference between the two.
One part of the difference is focusing on a sustainable lifestyle of eating, and the other part is a concern for muscle mass. Strength is youth.
What About Age?
Without consistent strength training you’ll lose 3-5% of your muscle mass each decade starting in your 30’s. This means that by the time you turn 50 you may have lost 10% of your muscle mass! Each pound of muscle mass burns calories at rest, and far more during any and all physical activity.
The good news is that it is never too late to start. Researchers have demonstrated that women can gain muscle mass into their 90’s, and that each pound of muscle will burn the same number of calories at any age.
Bottom Line
Strength training is the most important exercise you can do when you are trying to lose weight if you want to keep it off, have a high quality of life, and/or have a “toned” look. If you add strength training to even the most extreme diet – 800 calorie liquid diet – you can maintain or even gain a tiny bit of your precious muscle mass.