ELI5: If being in a caloric deficit is the only way to burn fat, and protein is the active macronutrient in muscle-building, then why is it impossible to simultaneously gain muscle and burn fat?

It’s not impossible, but if you try to do both at the same time, the process will be much slower, which can push whoever is attempting that into more unhealthy eating and exercise habits.

For instance, I started to lose weight in June, and I focused on getting the weight gone first and foremost, so I cut calories, and starting running regularly. By the start of September, I had shed 23 lbs, and was finally at my ideal weight, so I started looking into how I could actually look lean and toned, so I turned to weightlifting and other body weight exercises, and I eat around 2000 calories per day (keep in mind that I am a teen, and it’s doctor recommended that I eat this much on my current exercise program). And so far, it’s working for me.

Compare that to a few years ago when I wanted to do both at the same time. I did weight lifting and running every day, and still had a caloric deficit. I was losing weight very slowly, and eventually I just gave up

/r/explainlikeimfive Thread