@article{ref1,
title="Maximum and submaximum exercise tests in men and women in the seventh, eighth, and ninth decades of life",
journal="Journal of applied physiology: respiratory, environmental and exercise physiology",
year="1977",
author="Sidney, K. H. and Shephard, R. J.",
volume="43",
number="2",
pages="280-287",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0161-7567",
doi="",
url="http://dx.doi.org/"
}