For rehabilitation exercises for people with hand function problems; This exercise is very effective for middle-aged and elderly people to use for fitness, training the contraction of the muscles in the chest cavity, forearms, hands and wrists. Hold the grip ball between your hands, spread your fingers as wide as possible, and point your fingertips towards your chin. Lower your shoulders and elbows and clench your hands together. Maintain this pressure, stretch your arms forward while rolling your fingers forward.