Let’s cut to the chase. When someone says they want to lose weight, what do they really mean?
They want to lose FAT.
I have yet to meet anyone who had the goal to lose lean muscle. When we say weight loss, we really mean fat loss.
How you achieve fat loss can be very different than how you achieve weight loss. This is one of the reasons I say diets don’t work. A diet means calorie restriction, many times without exercise. Sometimes it can mean severe calorie restriction, far below recommended levels for health. When you follow this route you’ll lose weight, but more often than not it will be more lean tissue than fat.
Real life example, I finally got to do a body composition analysis on someone who was doing the current hormone based fad diet of the moment whose name I won’t speak. This person had one “round” left to go and a goal to lose 10 lbs. In two weeks they met their goal. However using before and after tests, their 10 lbs of weight lost was 8.5 lbs lean mass and only 1.5 lbs fat mass. This person, unlike most others on this program, was exercising as well.
Not the results they were hoping for.
I realize this was a somewhat unscientific study with only one data point, but it is very much in line with the research on weight loss.
On average with calorie restriction alone, 25% of weight lost will be muscle mass. We know this is not good because muscle mass fires our metabolism, so losing it will slow it down in the long term.
If our true goal is fat loss, then exercise (particularly strength training) has to be part of the equation. Cardio is good for us. It burns fat and improves our health but it does not preserve muscle mass. By adding strength training you can work to preserve, and in some cases add, muscle mass.
So when you are thinking about your goals ask yourself this: Do you just want to be a smaller version of your squishy self or do you want to be a new leaner and stronger you?