All you have to do is watch the news to know how important it is to stay in shape. In the short term, ramping up your fitness can give you more energy, improve the quality of your sleep, boost lung capacity, and relieve stress — not to mention help you work on that six-pack. The lasting benefits are even more impressive. An ever-growing body of evidence suggests that exercise strengthens bones, reduces joint pain and blood pressure, and even helps ward off some types of cancer. Plus, new research shows that regular workouts may help your mind stay nimble as you age. Want to see these and other benefits in the years ahead? Update your exercise routine now with help from the experts.

Add intervals

Mixing short bursts of effort into whatever you're already doing — walking, running, swimming, using an elliptical trainer, or cycling — is a great way to enhance your workouts without making them longer. Consider research published last year in the Journal of Applied Physiology. During the study, eight women in their 20s rode stationary bikes, alternating between very difficult four-minute energy bursts and two minutes of recovery. After doing ten sets of intervals every other day for two weeks, subjects' fat-burning capacity improved by 36 percent and cardiovascular fitness rose by 13 percent.

“What surprised us most was that we saw such a quick improvement in aerobic capacity,” says Jason Talanian, PhD, a researcher at the University of Guelph in Ontario, where the study was performed. Based on the results, Talanian recommends completing one or two interval sessions per week, working up to longer intervals. For instance, after a five-minute warm-up, speed up for two minutes, then work at a normal pace for the same amount of time; vary between hard and easy for about ten minutes. Gradually increase interval length by a minute a week until intervals are four minutes long. You should notice improvement in cardiovascular stamina after just a couple of weeks.

Focus on the core

By the time you hit the gym, you may be so intent to pound through that cardio routine that you forget to work one of your body's most essential muscle groups — your core. No longer synonymous with simple tummy tightening, core training strengthens all the muscles between your rib cage and pelvis to help you achieve greater stability, balance, and control in your spine, legs, and shoulders. “All movement starts from the very center of your body — what I call the pillar,” says Mark Verstegen, founder and president of Athletes' Performance training centers with locations in Arizona, California, and Florida, and co-author of Core Performance Essentials (Rodale, 2006).

As you age, not only will a weak core translate to less power when it comes to sports, but it also may inhibit range of motion and hip stability. What's more, your core supports your back, so keeping it strong will help protect against herniated disks in the decades ahead. “This is really prehab,” says Verstegen, “because it builds the kind of strength that helps you do all of your favorite activities — dancing, surfing, golfing, or anything — with less risk of injury and more power.” Many gyms offer Pilates, which strengthens the core through slow, repetitive movements. Or try a core-conditioning class that uses props such as stability balls to increase balance and range of motion. After you gain more confidence, check out instructional DVDs, such as Abs Conditioning: Yoga, BalanceBall, Pilates (Gaiam, 2003).

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