Rest days are an essential part of an exercise program. Your body needs about 48 hours to recover between exercises targeting the same muscle group. You can still exercise every day, just not the same muscle. Youth baseball pitchers need at least 24 hours rest after a game. Some runners rest once a week. Everyone is different. Rest needed depends on many factors including your age, activity, and nutrition, but everyone needs some. If you work out intensely but don't allow for down time, your body will be less apt to reap the benefits.

Joint Health

Exercise puts stress on the body, including the joints, which don't have much padding for projection from injury. The knee, ankle and hip joints take a particular beating with respect to the repetitive nature of running. Without regular rest breaks, they may become sore and swollen. A much needed rest between bouts of exercise will help avoid this problem and keep your joints healthy.

Injury Prevention

Rest days scheduled throughout your training period will help reduce the risk of injuries due to overtraining. Overtraining happens when too much stress is put on the body without adequate rest periods. It is much wiser to allow for rest days than end up benched for weeks or even months because of injury.

Muscle Repair and Strengthening

Rest days are crucial to facilitate muscle repair and strengthening. During exercise, you don't build muscle, you break it down. The building process happens during your rest days. Rest days help you recuperate so you can, for example, lift more, run faster and walk longer during your next workout session. Fitness and performance don't start to suffer until you take more than two weeks off of training.

Glycogen Restoration

The body uses glucose, a carbohydrate, as an energy source. Glucose is primarily stored as glycogen in the muscles as well as the liver. Glycogen breaks down within the muscles during exercise to give you energy to workout. Rather than loading up on carbs, however, concentrate on eating a healthy diet that includes many different foods, including those carbs, but that's low in fat.

Mental Health

Rest days help you regroup. Too much exercise without adequate rest can lead to burnout. You'll become physically and mentally drained and find it hard to drag yourself to the gym. Your health is too important to let that happen. Take those breaks, chill out, recuperate, restore your energy and come back refreshed, healthy and ready to dive into your workout again.

Signs of Inadequate Rest and Their Possible Solutions

The signs of inadequate rest are irritability, chronic soreness, weight loss, compromised concentration and performance, frequent illness and excessive tiredness. You can rectify these situations by taking days off to completely rest up. You can also schedule cross-training for your rest days 1. For example, if you're a runner, engage in a low-impact exercise such as swimming when you're not running. Light exercise on rest days can help keep you loose without overtaxing your body.