@inbook{1157196442, author={John P. Porcari and Cedric X. Bryant and Fabio Comana}, title={Fitness Across the Life Span: Introduction}, booktitle={Exercise Physiology}, publisher={F. A. Davis Company}, address={New York, NY}, year={2015}, url={fadavisat.mhmedical.com/content.aspx?aid=1157196442} }