On Tue, 26 Feb 2002 05:03:13 -0500, Jo Webb <[log in to unmask]> wrote:

>wondered if anybody knows of
>any studies which show that the usual recommendation of cardio for 30-50
>min 3-5 times a week is not well-founded?

People mean different things by cardio, but the main idea are studies
attemting to measure the effect of different exercise programs on
bone and muscle density, and that resistance and moderate
"low-impact" aerobics may be better than excessive aerobics, eg

http://otpt.ups.edu/Gerontological_Resources/Gerontology_Manual/Thachuk.html

Philip Thrift
http://www.geocities.com/paleofitness