Chair dips are a fairly simple exercise to perform that works the tricep muscles at the back of the upper arms. Many people who work out at home do chair dips as part of their routine because the exercise requires only chairs or benches that are probably already in the house. This exercise can be modified to make it easier for beginners to learn or much harder for advanced strength building.
The basic form of chair dips requires one bench or chair without rollers or moving parts. To begin, the exerciser should sit on the very edge of the chair or bench with his legs out straight with the heels resting on the ground, and grip the edge of the chair with both hands. Slowly, the exerciser should lower his body down in front of the chair, still gripping the edge of the chair with both hands and supporting his body weight with his arms. When the elbows reach a 90 degree angle, he should push back up and extend his arms until they are straight or nearly straight to complete one repetition. A workout that incorporates chair dips may include multiple sets of several repetitions at a comfortable speed, or fewer repetitions or sets done much slower and at a higher intensity.
If the standard position makes the arms or shoulders uncomfortable and puts too much strain on the joints, it may be beneficial to position two chairs slightly apart and perform the chair dips between them with the arms closer to the sides rather than behind the body. Beginners or those who lack sufficient upper body strength to complete this exercise may also find it easier to bend the knees, either slightly or all the way to a 90 degree angle, which allows the legs to take some of the weight of the body but still forces the arms to do most of the lifting. Over time, the legs can be gradually extended to force the arms to build strength and adjust to doing the more difficult versions of the exercise.
A more difficult variation of standard chair dips includes another bench or chair on which to place the feet, so that the legs and feet are elevated, still extended straight out in front of the body. Raising one leg or alternating which leg is raised during the exercises increases the difficulty even further and works additional muscles. With this advanced version especially, do not dip low enough that the elbows are at less than a 90 degree angle, because this can strain the shoulders and possibly cause injury.