tool for muscles

i will order this tool beside dumbles to help me buliding mucles working at home
is it good for building or just these tools used for stretching?!
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It's fine but I certainly don't think you need it. You don't even need dumbbells. You can just do calisthenic exercises using only your own body weight and get boys that way. I have four boys and I never used that thing or heavy weights, just did exercises that used my own body weight to build muscle.

ok now iam doing calisthenic exercise as you suggested
but what is the best time duration for them
is ten minutes everday enough?

It is fine to start with but I prefer to see you guys work up to 30-45 minutes of exercise. Part of this can be cardio, to help prevent excess weight gain on HE Diet, and part muscle building. It can be helpful to do about 30 minutes of cardio 3-5 times a week - things that also build muscle, like walking up and down stairs, or kickboxing, or HIIT style workouts are great - and then 15-30 minutes of muscle building 3-5 times a week. We want you to have at least 2 days a week off - so two days without any exercise at all. So you can arrange your exercise on the other days to be all cardio some days, all weights some days, or small amounts of both. Your choice.