Reuters recently reported on a study from The University of Queensland in Australia which indicates that without weight loss you can be as fit as a fiddle but your health will still suffer if you remain obese.
IOW, you can do your cardio till the cows come home but unless you slim down, the supposed health benefits of cardio are not forthcoming. (And the best way to slim down is to dine paleo.)
What this means is leanness, not cardio, is what is health protective.
So when folks do a ton of cardio, eat right and lose weight, they assume that it was the cardio that lowered their blood pressure, improved their blood-vessel function, etc. Not according to this study.
Things are not always what they seem eh?
We know that the amount of blood flow in our limbs and the flow of blood through our veins and arteries, organs, etc., decreases as we age. The cold hands and feet of the elderly, is such a sign of poor blood perfusion.
We also know that this decrease contributes to or can contribute to cardiovascular disease.
A study by Anton MM, Cortez-Cooper MY, DeVan AE, Neidre DB, Cook JN, Tanaka H. titled: "Resistance training increases basal limb blood flow and vascular conductance." which appeared in the Journal of Applied Physiology. 2006; 101: 1351-1355 found that strength training and not stretching exercises improved blood flow.
And guess what?
Anton found in another study he conducted that aerobic training did not produce favorable changes in blood flow.
If you had to guess the outcome, I doubt anyone would guess that aerobics does zippo to improve blood perfusion. In fact, you'd bet the farm it would.
Sometimes things are really not what they seem right?