Single-function trainer: common rowing machines, exercise bikes, walking machines, treadmills, waist-beautifying machines, treadmills, etc. Their main functions are: rowing machine-mainly used to increase arm strength and action coordination. Exercise bike-like riding a bike, it is mainly used to increase leg strength and enhance cardiovascular function. Walking bike-mainly used to exercise the muscles and cardiopulmonary functions of legs, waist and abdomen. Treadmill-mainly used to exercise leg, hip, waist, abdominal muscles and cardiopulmonary function. Waist beauty machine-can relax and massage the waist and back. Stair machine-also known as stair machine-is a simulator for going up and down stairs, which specializes in training leg muscles. Elliptical machine is a kind of fitness equipment which integrates walking, jogging and static riding. Its fitness action is consistent with the natural stride of human beings, which will not cause great impact and damage to human joints, and can simultaneously move the muscle groups of upper and lower limbs, especially the legs and buttocks. Multi-functional trainer: generally including chest enlargement, pull-ups, sit-ups and other functions. Chest enlargement, pull-ups and supine pressing are mainly used to exercise upper limb strength and pectoralis major strength; Sit-ups are mainly used to exercise waist muscles and reduce excess fat in the waist and abdomen. In addition to these big pieces of fitness equipment, you can also choose some small pieces of equipment to enrich the form of exercise, such as skipping rope and fitness balls. In addition, if you feel that the one-time investment is too large, you may wish to buy some dumbbells, spring tensioners, elastic rods, disks and so on. First, you can also use these cheap and good equipment to keep fit.