The term 'limber up' is a phrase used to describe the process of preparing the body for physical activity. This can be done through EXERCISE and stretching, which are both activities that help to increase flexibility and reduce the risk of injury. EXERCISE, which has 8 letters, is an activity that involves physical exertion and is used to improve health and maintain fitness. Stretching, which has 7 letters, is an activity that involves lengthening the muscles and tendons in order to increase flexibility and range of motion. Both EXERCISE and stretching are important components of limbering up and should be done prior to any physical activity.