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What are Carbs and Fats Used For...


...when building muscle?

From what I've read, it seems that protein is broken down into amino acids, many of which humans can't synthesise themselves, and then these are used to build new muscle fibres during the repair stage that follows muscle damage from lifting heavy weights. So increasing protein, up to the point where more protein can't be effectively used in this process, encourages muscle growth.

But what do the fats and carbs do besides provide energy for workouts? And is there any benefit to eating say 5000Kcal/day rather than 3500 when bulking up? What happens if someone eats their 'maintenance' (RMR+Energy expended from exercise, moving about etc) with 1.5g+ of protein/ lb body weight and the rest from a balance of good carbs and fats (whilst also lifting heavy)?

I've seen some people taking 'weight gain' shakes that have massive amounts of sugars etc. in them which surely just leads to gaining fat and doesn't help much with building muscle?


search through some of very few articles on this site if your lucky you may find one or even two


I'm honestly too damn lazy to give a super detailed answer, but fat and carbohydrates provide energy for basically every process imaginable that occurs in the body and for everything you do.


Cool story bro!

You have a WHOLE lot of nutrition education to catch up on which can't be discussed here.

As of now, you're totally clueless.


Have you ever bothered to pick up the most basic book or article on nutrition or even a scientific one?


The question wasn't what are carbs and fats used for in general, it was how specifically do they contribute to muscle repair and what sort of diminishing returns are associated with an increase in fats/ carbs.


carbs and fats makes you feel fuller for longer

if consumed after workout = insulin spike=less IGF-1

if taken with whey protein = faster recovery but still low igf -1

same if taken before workout

but not ideal to have when trying to lean out


Same reply: educate yourself on nutrition.

And here's the elementary answer to your elementary question.

If you eat too much, you get fat.


carbs/fats allow your body to use the amino acids in protein. Think of protein as the bricks of a house, and carbs/fat as the workers who lay the bricks. No one can tell you how much carbs/fat/protein you PERSONALLY require to grow because it varies by person.