U need not do every day to gain muscle.Muscle gains when you give rest and supply nutrition for recovery post workout.
To gain muscle for a teenage boy, you have to do some exercise every two days like running or cardio. You can go in a gym and do some cardio. It's good for you muscle.
By getting exercise.
It could be the increase of muscle.
Answer: Your frame size will become larger so you will gain weight, but not from muscle mass. You can gain muscle mass from exercise.
Exercise in a way where you don't lose weight but gain muscle weight.
high protein diet with regular exercise,
Eating tuna helps to gain muscle because tuna is protein and protein builds muscle. However, to build muscle you need to exercise as well.
It is best if you give a muscle group at least a day or two of rest to give time to GAIN the muscle. If you lift every day you aren't going to gain good muscle mass.
It only provides increased amounts of the nutrients necessary for muscle growth. If you do not exercise, no. You will only get fatter.
If you are gaining muscle, muscle weighs more than fat, thus making you gain wait even though you can possibly look smaller, but leaner.
A good balanced diet and plenty of exercise. weight gain in muscle is far more attractive and healthy then weight gain in fat.
Exercise, like in any other gym.