Losing weight altough eating normal because of bouldering?

Question

I have always had a bit of fat on my body. I was never fat nor even chubby but always 4-5kg too much on myself. I just thought it to be my genes because my whole life i did a bit of sports. Going bycicling sometimes, going swimming, skating, ice-skatin, skiing. I did everything.

Nothing regularly but sometimes. And at my parents altough i ate sweets they cooked fairly healthy. So as stated, i just thought it to be in my genes, to gain fat a bit faster.

But in the last 4-5 months i started going bouldering regularly 2 sometimes 3 times a week for 2-4 hours each time. I dont think that this extremely much of a sporty activity, but still i lost 6kg in these past 4-5 months, altough i built a hella lot of muscle which is actually much heavier than fat. So i must have lost at least 10kg of fat(currently 72kg at 176cm).

But the thing is, i do ate almost the same. Every now and then a Kebab or Burger or yesterday for example a whole 0,5kg cup of ben&jerrys. And everytime after bouldering i drink 1-2 beers (the reward of course ;) )

I was training in the gym earlier in my live and noticed no real weight loss.

How can his be? Is doing something regularly so much of an impact on the body? Is maybe bouldering such a good sports of loosing weight because you need to whole body for it, in contrast to working out in a gym? If yes, how does this work? Is the metabolism so turned on or what is the reason for my pretty significant weight loss?

This is my first time here in FitnessSE and i hope this question is in the scope of it :) If not let me know and i will change the question accordingly

Answer 1

Thanks for showing a great example of what's known via studies: strength training provides exceptional fat loss, more so than aerobic activity. That linked answer has most of the tidbits, but the short version is that muscle is extremely expensive for your body to maintain.

Plus, during those 8-12 hours a week your heart is pumping and you're in a low level aerobic range as well. Also, you're (probably) not eating during those times.

Putting it all together (muscle gain) + (aerobic activity) + (less time eating) = better body composition towards lean muscles and less body fat.

Good work!