According to a study from Loyola University School of Medicine published in the Journal of Physical Activity & Health in January of 2014, physical activity extends the life of men with cancer by as much as 38% as well as reducing mortality from cardiovascular disease by 49%.
These researchers found that in 1000 men with cancer that burning 12,000 calories per week vs less than 2100 resulted in a 48% lower all cause mortality rate. An average 175 pound man walking briskly for 30 minutes for 5 days a week burns 4200 calories. Of course, judgment needs to be used regarding when to do exercise and when to rest. As usual, one size fits all is nearly always a myth!