Arnold did a lot of steroids and probably not a lot of cardio.
Running will quickly put you in a calorie deficit if you aren't careful to add in caloires to compensate...which leads to muscle loss, a runner's body is not typically a muscualr body.
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A man of sense is never discouraged by difficulties; he redoubles his industry and his diligence, he perseveres and infallibly prevails at last.
.... Do alot of cardio like running or anything like that? i wanted to know because i wanted to get into running and maybe running up and down the stairs but i didnt know if cardio causes you to loose muscle because i just want to loose fat and no muscle at all. so i figured if arnold ran or did any other cardio then maybe it would be good for me to do that. what do you guys think?