If the waist is pulled hard, you can use a barbell or dumbbell. Of course, within your tolerance, it is better to be heavier. When pulling hard, pay attention to keep your back straight, your ass pursed and your knees slightly bent. Group of 20, 3-4 groups at a time.

Arm If you mean the back of the arm, it's three heads. Use dumbbells, arms up, elbows on both sides of ears, hold dumbbells in both hands and bend back. 20 in each group, 3 groups at a time.

Aerobic exercise generally refers to running, cycling, brisk walking and dancing. Anaerobic generally refers to the training of instruments.

If you want to lose weight, the most effective way is to run for an hour every day. Pay attention to warm-up and stretching, and don't get hurt.