Is 40 really the new 30? That would mean 50 is the new 40, 60 the new 50, and so on and so on. With our ever-improving knowledge of nutrition, exercise and skin care, we have the potential to be healthier, live longer and look better than ever. But there’s one über-important factor preventing you from cannonballing gleefully into the fountain of youth: your hormones.
To be blunt, your hormones screw you as you get older. After age 30, a man’s testosterone levels drop by 1 percent per year, a woman’s estrogen/progesterone balance falters, and everyone’s growth-hormone levels begin their steady march south. Weight gain, decreased muscle mass, insomnia and a low libido are a few of the lovely symptoms that accompany this natural and inevitable hormonal decline, and short of replacement therapy, there’s not much you can do to reverse this natural and inevitable decline. Or is there?
As it turns out, high-intensity workouts — like those practiced regularly in CrossFit — can reboot the body’s hormonal systems and increase longevity. Most notably for those of us in the masters demographic, HIIT training has been shown in numerous studies to stimulate the release of growth hormone, the big-daddy hormone responsible for an increase in exercise capacity, fat metabolism, bone density and muscle mass. In fact, in one study, published in PLOS One in May 2013, just four minutes of HIIT boosted VO2 max (a measure of cardiovascular endurance) by 13 percent, reduced cholesterol and blood pressure, and improved insulin sensitivity by about 24 percent. In a study out of Australia that followed more than 204,000 people 45 and older, regular high-intensity training reduced the chances of dying by 13 percent. And in a recent study published in the Journal of Strength and Conditioning Research, HIIT training was shown to increase testosterone levels in both men and women.
In addition to building muscle and boosting metabolism, resistance exercise also releases growth hormone into your system, but the amount released is directly related to the intensity of the activity being done and the muscle fibers being activated. The body has three kinds of muscle fibers: slow twitch, fast twitch and super-fast twitch. The fast and super-fast fibers produce the most growth-hormone response and are only activated during high-intensity exercise when you train at or above your anaerobic threshold. Remember that brutal team-rowing program you did last month that made you want to stagger into the corner and hurl? Besides nauseating you, it pumped you full of growth hormone as your fast and super-fast fibers were worked and spent.
So where does that leave us? Yes, your hormone levels are declining, but that does not mean you have to sit back and accept your fate. As a CrossFit athlete, you’re already one step ahead of the game, so continue to push yourself with each and every workout. The next time you’re doing an AMRAP and want to ease back on the throttle, imagine your growth-hormone levels skyrocketing as you go for one more round. Push through that torturous Tabata of AbMat sit-ups at the end of an already grueling workout. Keep testing your limits and toeing the edge of discomfort, and turn back the clock a tick or two. Or at least hit the pause button on Father Time’s inexorable march forward.