There are about 300 chairs in the gym, and the chairs in the gym are 1. The height of the seat should be equal to the length of the calf. After sitting down, the calf naturally hangs down and the sole of the foot just falls to the ground. Too high, the calf is suspended, and it is not good to be oppressed under the thigh for too long; The seat surface is too low, the thighs can't be placed on the seat surface, and the weight of the human body is concentrated on the buttocks, which will be uncomfortable for a long time.

2. Seat depth: The depth of the seat surface of the chair mainly used for sitting should be equal to the length of the thigh. After sitting down, the knee joint bends just to the edge of the chair, the chair surface is too deep, and the back has not landed; The seat surface is too shallow, the thigh support is not enough, and it is uncomfortable.

3. Material of chair surface and chair back: both should be "soft outside and rigid inside"-the bracket should be strong enough, but the surface should have an elastic layer with a certain thickness. The outermost material in contact with human body should be breathable, wear-resistant and dirt-resistant, and it is not easy to generate static electricity with human body or clothes.

4. Chair: It is best to support the waist, back and neck in whole or in part. The longer you sit in the chair, the better support you will get. Dining chairs can be ignored, because they are only used when eating, while office chairs are best taken care of. The size of imported furniture is often more suitable for the people in the producing country, so we should pay special attention to it when choosing.