The copenhagen study is one that stays with me. Over a period of 35 years, and ~17000 people, there are some interesting charts showing guidelines to optimise jogging for longevity.
If I recall correctly, the best benefit was for joggers to run three times a week for 7 kilometers at 7 kilometers per hour. This would give an extra five years of life, and as the parameters (#times per week, distance, speed) veered from this benefits declined along a bell curve.
Interesting bit about 7 kilometers per hour. That's almost walking speed.
Re:Does Exercise Slow the Aging Process?
by loco5niner on Thursday October 29, 2015 @01:11PM
(#10472579)
Hmm... that's 4.3 mph, or 4 miles in 56 minutes, or 14 minute miles. Not very fast at all.
Dose of Jogging and Long-Term Mortality : The Copenhagen City Heart Study http://dx.doi.org/10.1016/j.jacc.2014.11.023
Working up a sweat -- it could save your life http://www.eurekalert.org/pub_releases/2015-04/jcu-wua040215...
Lack of exercise kills roughly as many as smoking, study says http://latimesblogs.latimes.com/world_now/2012/07/lack-of-ex...
Every Minute Of Exercise Could Lengthen Your Life Seven Minutes http://commonhealth.wbur.org/2013/03/minutes-exercise-longer...
And so on. There's a lot more out there on exercise and mortality risk as determined from large epidemiological data sets in humans or cause-and-effect animal studies if you care to go look around. One present focus is trying to pin down the dose-response curve, for example.
Telomere length, as measured in the study linked here, isn't worth paying much attention to. There are many, many problems with linking average telomere length in white blood cells to specific outcomes in aging. In many ways it is even more of a fuzzy number than, say, BMI or exercise level.