ウエイトトレーニング
Weight training is usually isotonic in nature. This means that the joint angles change during the exercise i.e. it is dynamic in nature and involves moving. This can be contrasted with isometric exercise where the joint angles remain constant i.e. the exercise is static in nature and involves holding a posture. A weight training exercise may involve both isotonic and isometric elements i.e. squating with weight usually involves bending and straightening the legs (an isotonic action) while holding the weight steady (an isometric action).