Deconditioning is a complex process of physiological change following a period of inactivity, bedrest or sedentary lifestyle. Prolonged bedrest can affect virtually all systems in the body, including the heart, lungs, and even the digestive tract. It especially affects the musculoskeletal system. Deconditioning causes decreased muscle size, increased weakness (atrophy), osteoporosis, contractures, osteoarthritis, and loss of flexibility. It results in functional losses in such areas as mental status, degree of continence and ability to accomplish activities of daily living. Some children may have trouble sitting up in bed, standing or even walking. Others are too weak to even brush their hair or dress themselves. For these children, a re-conditioning program may be needed.
Kramer, A., Gollhofer, A., Armbrecht, G. et al. How to prevent the detrimental effects of two months of bed-rest on muscle, bone and cardiovascular system: an RCT. Sci Rep 7, 13177 (2017). https://doi.org/10.1038/s41598-017-13659-8