I'm 39 and have been an avid runner for 3 years or so in a quest to get lean. I think however, it has compromised my testosterone levels. If I shift to a treadmill based thrice weekly 20 minute high intensity interval type of cardio, will I protect my testosterone or continue to screw it up?
Intervals will help restore your lean body mass to some degree, and certainly more so than the muscle-wasting endurance running.
Have you considered doing some strength training, too (say 2-3 sessions x 30 min / week or so)?
Strength training and good nutrition = more testosterone = muscle = more lean, which will also benefit your health in other ways.
As a former runner (up to 35 miles/week, inc. half-marathons), I can atest to both sides of the story. High intensity strength training and "cardio" are much better for your lean body mass.
Oh yes, I'm strength training as well. I was just wondering if the interval cardio would hurt my t-levels as it may affect me in the arena of muscle gain and libido.
First of all how do you know that your T has been "compromised?" I have never seen moderate running (3 days per week) compromise anyones T levels.
I've seen numerous reports about cardio and decreased testosterone. In fact, I used to have similar issues when I used to peak for races. Nothing gynomastia related but definitely decreased sex drive. This past season I've been supplementing with Alpha Male and (along with increased performance) I did not have any of those effects. I've also been following a hormone friendly diet f/ Eric Cressey and things are even better.
What are you training for?, What are your goals?
My goals are to be as strong, lean and muscular as possible along with bolstering libido which is the top priority. I'm currently over 205 bodyfat despite going for ten mile runs. Youre never gonna come back and look at this thread again are you?
if your trainingfor endurance try some boxing. It kicks ass as a cardio workout and will sure kepp ure t levels up!