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09 Dec 2005

Muscle gain and fat loss
When you go on an exercise programm you put on weight on the scale (muscle gain) but lose centimeters right?

But how do you know how much is muscle and how much is fat and which one you are gaining or losing when all you have to work with is a scale and a tape measure??

I guess what I am really asking is how much fat can you lose by exercise alone and how much can you lose when exercising and dieting?

How long would it take to lose 12kilos? I am 65kgs now and want to be at leaat 12kgs lighter (I'm female, 5f3) and do cardio activities 30min per day 5 days per week
Answer 468 views

01 Jan 0001

hi there

Good question, and the answer is that if you only have a scale and tape measure at your disposal, you cannot realistically work out how much fat is lost and how much muscle is gained. You need special equipment which can measure body fat percentage and lean muscle mass very accurately. So you have to try to understand and interpret what is going on, rather than worry about the exact amounts and so on.

To answer your second question, the amount of fat you can lose depends on how much you had to begin with. For example, someone weighing 100 kg with 40% fat (therefore, having 40 kg of fat) can quite realistically expect to lose about 10 kg of fat, and therefore come down to 90 kg, with 30 kg of fat (for a new fat % of 33%). On the other hand, if you are at 65 kg and say with 30% body fat, then losing 10 kg of fat only will bring you donw to 55 kg and 10kg of fat, which is below 20% and this to me is unrealisitic. So the bottom line is that you can lose more when you have more. In your case, your BMI is at just a shade over 25, and 25 is considered the upper limit of normal. So, if you were to lose 12 kg, your BMI would come right down to 21, and I think that this is too large. I therefore don't believe that you should aim to lose this much weight. I have heard dieticians talk about losing about 10% of your body weight quite safely, which means that you could lose about 6 kg.

So my advice is to aim to lose about 5 kg, but keep in mind that as you lose fat, you gain muscle. This only happens up to a point and depends on your training, but you can probably expect to increase your muscle mass by a couple of kg, which means that to 'break even' you have to lose 2 kg of fat.

At the end of the day, you must focus on getting fitter and getting yourself feeling stronger, and looking leaner and try not to worry about numbers too much

Good luck
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