You don’t. Lift weights, eat right, and grow up.
To make your muscles grow fast you need a protein rich diet and adequate exercise.
They eat and they get muscles?
There are fast twitch muscles fibers in all of your muscles, especially in your legs.
No because the muscles need protein to grow or maintain themselves, if you are not getting protein they can't maintain a constant size or grow more and will lose bulk.
Yes, the Human Growth Hormone (HGH) can make your muscles grow
Anyone who is healthy enough to tolerate exercise can grow muscles. From young children to senior citizens.
mainly the muscles in your forearm, if you alternate pick fast ( pick up and down fast) you either use your wrist muscles or elbow muscles depending on what moves, your wrist of elbow.
Don't you mean, "how fast do your fingernails grow?"
The muscles their legs developed so they can run fast
If you want orbeez to grow fast you will need to put it in hot water.It will not grow fast but it will grow bigger.
Exercise
YES