When Rest Isn't Best

Rest, icing, compression, and elevation (RICE) are commonly recommended for sports injuries such as strains, sprains, stress fractures, plantar fasciitis, patellofemoral disorder, or IT band syndrome. However, prolonged rest results in rapid deconditioning and can lead to a cycle of chronic injury. Cross training allows athletes to remain as active as possible without aggravating injuries.

What is Deconditioning Syndrome

Deconditioning syndrome is the reversible deterioration in body systems due to physical inactivity. It results in a loss of cardiac function and muscle strength and is often accompanied by depression and weight gain.

After 10 to 14 days of physical inactivity VO2 max, the body’s ability to uptake and use oxygen, begins to decline.  This is due to decreases in cardiac output, blood volume, and capillaries. Deconditioning studies have shown a 10% loss in VO2 max after 10 days for astronauts in zero gravity environments, and a 20-25% loss of VO2 max after 30 days of bed rest.

Inactivity has a slower impact on muscle strength. During the first few weeks changes in functional strength are minimal. However, MRIs of space shuttle astronauts’ calf and quadriceps muscles showed a 6% volume reduction after 8-days of microgravity, and a 24% loss after 6 months. In people on bedrest, calf and quadriceps muscles showed a volume reduction of 16% after 20 days and 45 % after 90 days.

Inactivity also effects emotional health. A sudden decrease in physical activity can cause sleep disruption, fatigue, weight gain, and depression. Cortisol levels can become chronically elevated which interferes with the healing process.

Preventing Deconditioning Syndrome During Injury

With sports injuries, complete rest is usually not the best treatment. Remaining as active as possible without aggravating the injury is a better approach. Cross training activities such as swimming, cycling, pool running, and rowing and elliptical machines can reduce loses in VO2 max while an injury is healing. Aerobic exercise also improves circulation to injured muscles and tendons and increases the release of human growth factor which facilitate repair. Loss in muscle strength can be minimized by continuing to train uninjured muscle groups when possible without irritating the injury. Exercises prescribed by a physical therapist or exercise physiologist to can aid in retaining muscle strength and preventing future injuries. Maintaining a healthy diet and getting regular sleep also promote healing and reduce the effects of deconditioning syndrome.

Identifying and Correcting Underlying Issues

Injury and the resulting deconditioning and can lead to a cycle of chronic injury. It is important to identify and address the underlying biomechanical problems, muscle imbalances or weaknesses, nutritional deficiencies, or training errors that caused the injury.



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