Exercising can help to clear our skin and defy aging.

Lifting weights, doing aerobic workouts, and stretching into a yoga pose all benefit your skin as well as your body.

Most of the time, exercise conjures up images of losing weight, building muscle, and trimming thighs. But now, doctors say, another body part may benefit from regular workouts -- your skin.

Indeed, from reducing acne breakouts to fighting the signs of aging, health experts say regular exercise can play a big role in how young and how healthy your skin looks and feels.

What it happens is increased circulation and delivery of nutrients to skin cells, whooshing away potentially damaging toxins. Another is giving skin the optimum conditions for making collagen, the support fibers that help keep wrinkles and lines at bay.

But perhaps the most dramatic effects of exercise are on acne-prone skin. Doctors say working out provides many benefits that can help clear the skin. How? Exercise mediates the production of testosterone-related hormones such as DHEA and DHT. There's a lot of indirect evidence that shows that when you exercise your level of stress diminishes. So your adrenal glands are producing less of these male-type hormones that are part of any acne flare-up. The proof? Try to remember any situation that increased your stress level -- meeting a deadline, receiving an unexpected bill that needs to be paid, disagreements in family -- and you're likely to recall a breakout. Almost everyone's skin flares when they are under stress but especially those who already is prone to acne. Exercise, can help control it. By reducing stress, it tends to quiet the adrenals. There is less hormone output which in turn helps control acne.

According to dermatologists, regular exercise also increases sweating, which in turn can unclog pores and have a positive effect on breakouts.

In the long run, people who exercise have a better complexion overall. If they have acne, it's better controlled, and if they have occasional breakouts they are definitely less severe, and clear quicker and easier.

This same hormone-reducing activity can also benefit your hair. Anything that controls the amount of male hormones your body produces can impact not only skin, but also androgenic hair loss. Anything you can do to reduce the production of these hormones is going to have beneficial results on both skin and hair.

While we don't often think of exercise has having any specific anti-aging effects on skin, experts say it most definitely does. One is by influencing the natural production of collagen, a kind of connective tissue that plumps your skin and gives your face the bloom of youth. Our fibroblasts, which are the collagen-producing cells in the skin, became fewer in number and they become lazy as we get older. Skin becomes less firm, drier, and even more wrinkled. However, add an exercise routine to your beauty regimen and you infuse skin cells with oxygen as well as other nutrients. Both set up ideal conditions for collagen production.

Beyond helping your muscles relax, doctors say most aerobic exercise, such as walking or bicycling, also offer a "cleansing" effect on skin. This helps remove toxins that assault the skin --like cigarette smoke, air pollution, even chemicals commonly found in grooming products such as hair spray, deodorant, and shower gels. The better your circulation, which is something aerobic exercise can improve, the more effectively toxins are removed. The better and healthier your skin will not only be, but also look.

What can help your skin even more: Hydrating your body before and after exercise.

If you are properly hydrating yourself during exercise you will get better blood flow to the skin, which in turn encourages the elimination of toxins that would otherwise accumulate in the skin cells. This is particularly true for those who overindulge in alcohol, drugs, or even junk food.

Proper fluid intake -- water in particular -- can increase skin blood flow, allowing the washing out of those toxins, which in turn will help skin not only look better but also be healthier.