Determination of muscle mass changes in legs from 40K measurements
Palmer, H.E.; Rieksts, G.A.
Aviation Space and Environmental Medicine 50(9): 961-963
1979
ISSN/ISBN: 0095-6562 PMID: 496773 Document Number: 143870
The 40K content of the upper legs was measured periodically with detectors in subjects whose injured legs had been in a cast for 6 weeks or more. As the subjects began using the leg again, the 40K content increased as the muscle tissue was replaced. A 25% increase in 40K content in 6 months was typical for normal leg use and recovery. This is equivalent to an original muscle mass loss of 20%. By measuring specific body regions, such as arms or legs, with a high-efficiency detector system, muscle mass changes which exceed a few percent can be measured. These methods could be used in space flight and bedrest studies and in studying nutritional deficiencies due to diseases or diet.