how to gain the muscle without gaining weight?

some people gain the muscle but have so much little fat in their bodies like ballet dancers. i know you would gain weight still because of the muscle, i just want to know how to take the fat away?

it depends on type of training. as you said ballet dancers have defined muscles because they repeat practices numerous times. that gives the muscles flexibility, endurance and shape. it is opposit to pumping the muscles, what you do in a gym with heavy weights and low amount of repeating the practice. when you pump the muscle, it grows, and while it grows it needs more food to allow its grow = more weight.
if you want to lose weight and have great muscle tonus you need practice with no or little weight, but with numerous repeating, and of course large amounts of weater intake. last thing you need is patience nothing comes fast

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