Tip of the Week: While I'm sure you're familiar with the undeniable benefits exercise can have on your body, did you know that it can also be highly beneficial to your mental function, helping keep your mind sharper, alert and relaxed? It's true. In fact, numerous studies have born this out.

Harvard associate professor of psychiatry John J. Ratey, M.D., has found that just eight to 10 minutes of moderate exercise (60 percent of maximum heart rate) can enhance learning ability, while researchers at Duke University Medical Center discovered that aerobic exercise can decrease depression and improve brain function in middle-age and elderly men and women.

Of course, I don't need university research to tell me that exercise is a great mental stimulant. Whenever I exercise, I feel so much more alert and alive than when I don't. In fact, I often find myself a bit "down in the dumps" when I miss a workout, which is something I try not to do too often.

The next time you exercise, consider the mood you're in before you begin, during and after. I have a feeling you'll experience what I do, and once you do you'll be that much more likely to get back to it, for your mind as well as your body.

Q: What are your thoughts on stretching? Is it as important as some say? And if so, when should it be done — before, during or after a workout? Also, how can I tell when I've stretched enough? I don't want to pull a muscle.

A: I've generally found that most people don't pay enough attention to stretching, much to their detriment. Stretching improves circulation and flexibility, and is one of the best preventatives to disease I know of.

As for when to stretch, I suggest during and after your workout. A number of people stretch before exercising, but I've seen a study that says stretching actually weakens the muscles a bit, so you're going into a workout with compromised strength if you stretch beforehand. Also, if you think of your muscles like rubber bands you'll want to warm them up before pulling on them. We all know what happens to a cold rubber band when you stretch it out.

You should never feel pain when stretching. Mild tension in your muscles is perfectly acceptable, but nothing more. Also, never bounce into your stretch. Breathe deeply, and increase the stretch as you exhale, in a slow, controlled manner. Bouncing can lead to injury, which is something you're trying to avoid by stretching in the first place.

Q: I have tennis elbow and find it difficult to perform certain exercises, particularly for chest and shoulder training. Usually, it's movements in which I'm pressing the bar, either above my head or off my chest.

A: That reminds me of the old Henny Youngman joke: The patient says, "Doctor, it hurts when I do this." The doctor replies, "Then don't do that!" In other words, avoid pressing movements.

But seriously, folks ... tennis elbow, or any kind of joint problems, is no joke. I and most of my friends have suffered various joint problems over the years, and so I can empathize with your particular situation.

While it's true that you should avoid the exercises that aggravate your elbow, you may find that your upper-body exercise choices become severely limited. In this case, I have a few recommendations.

For one, get yourself a good therapeutic elbow wrap. Joint compression can help control movement and keep swelling down. In addition, make sure to warm up all of your joints thoroughly before putting any real stress on them. Likewise, you can reduce inflammation or swelling with an ice compress after exercise.

Finally, figure out which exercises you can perform with minimal discomfort and focus on those. I would also try to rotate exercises frequently — as in from workout to workout. Most joint pain is due to repetitive motion. By changing up your exercises, you can help alleviate this problem and save your joints undue wear and tear.

By taking a sensible approach to training and keeping the need to protect yourself front and center in your mind, you can go a long way toward reducing the impact your tennis elbow has on your level of physical activity.

Joe Weider is the co-founder of the International Federation of BodyBuilders, creator of the Mr. Olympia and Ms. Olympia bodybuilding contests, and publisher of numerous fitness magazines. To find out more about Joe Weider, write to him and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate web page at www.creators.com.

COPYRIGHT 2008 CREATORS SYNDICATE INC.