I'm skinny, if I do cross fit will i gain muscle or lose wait?

Since muscle weighs more than fat you will gain weight (assuming you are eating right) and will gain muscle. If you are skinny then there is really no body fat to lose either. Continue to eat right and cross fight will help you tone and build.

cross fit will never build muscle, just increase your cardio and tone your muscles a little bit. If you want size just weight lift and a little bit of cardio (five minutes of 30 second on 30 second off sprints)

If you wanna get muscles you have to eat like their is no tomorrow! Bodybuilding is 30% training and 70% food. If you dont eat enough your body cant get enough energy to build new muscles. So eat alot of healthy stuff and get enough protein in your system.

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