Here are some simple freehand fitness methods.
Exercise time 15 ~ 18.
Abdominal muscles: sit-ups: exercise waist and abdominal muscles. Sit-ups, feet up, thighs close to the body 90, calves relaxed and crossed, hands on your sides, but don't touch your head. When doing it, lift your abdomen hard, but don't lift it completely. The waist must always stick to the ground, do it 30 times quickly, and do 3 groups to exercise four abdominal muscles. Lie flat on your back, elbows on the ground, feet on the same level, then throw it up hard and retract it when your legs are thrown to the highest point. Repeat 15 times and do 5 groups to exercise the following four abdominal muscles.
Arm: How do you measure how much you have done when you practice biceps with reverse grip pull-ups? Try to breathe in one breath first, then reduce 2~3 to a group and make 3 groups. Push-ups are better for triceps, and your hands should be narrower than your shoulders, otherwise you should practice elsewhere. When you do it, your elbows will be sandwiched between your sides, 5 groups, 8~ 12 each.
If you have leg muscles, just do some squats every day. Remember to keep your ass down and your back straight when you do it, and jump with your feet immediately after you finish it, which will also help you jump.