FOR THE RUNNER who can't get out on the road or the tennis player who can't serve because of an aching back, hearing from sports medicine experts that no sport is intrinsically bad for your back, or that sports don't cause injury, they just bring out an existing precondition, is not terribly comforting.
All the weekend athlete really wants to know is which sports are pain free and which ones might be accompanied by some back pain.
Sports that qualify as pain free are swimming, walking and cross-country skiing, because for the most part they can all be done without sharp, sudden movements, hyperextension (severe arching) of the back, twisting or rotating the trunk, heavy impact and unexpected, awkward falls actions that a person with an iffy back should stay away from.
As far as most other popular sports are concerned, you're not going to get a blanket yea or nay from the experts: The safety of the sport depends on what type of back problem you have, your level of conditioning, and your technique.
Still, with all the hedging of bets, some areas of consensus emerge. Here's a sport-by-sport rundown, with one overall common-sense caveat: If it hurts, don't do it!
RUNNING. Look around enough and you'll find a practitioner who'll tell you running is no problem for a bad back, but most experts agree that back problems can come from the impact of the foot strike, abnormal foot mechanics, making imbalanced muscles work harder, and running out of your aerobic range (running too fast). Dr. Lyle Micheli, who finds running and people with ruptured disks particularly incompatible, will try to get the nonfanatic fitness jogger to switch over to swimming or cycling. For the patient who loves running and can't live without it, he'll have him cut back to every other day, run on soft surfaces, and get the most impact-absorbent shoes he can find. Micheli and Irene Dowd are also both fans of running in deep water with flotation vests as an antidote for road shock.
BICYCLING. With its low-impact properties, cycling could almost be classified as pain free. About the only area of dispute concerns which type of biking posture is most congenial to back health, with support being fairly evenly split between the body-over-handlebars style preferred by racers and the midway position used on a mountain bike. (Least conducive to back health is the completely upright position demanded by traditional touring bikes.) Points of total agreement are that you should pick the position that's comfortable for you, and that it's not good to be in a fixed riding position for long periods of time.
TENNIS. With its combination of vigorous torsion, flexion and extension movements, tennis is considered challenging for people with any kind of back pain, especially if they're out of shape or not fully warmed up. The same is true of other racket sports. Micheli counsels the avid but back-plagued tennis player to flatten out his serve (eliminating excessive arching and twisting), and to wear an elastic back brace with plastic inserts to protect against ill-advised motions.
AEROBICS. Dowd calls aerobic dancing terrible for all kinds of low-back pain, and adds that if you have back problems, "your chances of doing well in an open aerobics class are very low." The ways to turn aerobics from a high-risk to a lower-risk proposition are to get individual instruction rather than group; do low-impact rather than high-impact, and -- best idea -- opt for water aerobics.
BASKETBALL. A high-skill sport that's dangerous for the desk jockey who does no other conditioning, then goes out and plays a hard game once a week. You should have a decent level of muscular strength and fitness to do this safely. Basketball is an especially poor idea for the player with a herniated disk.
DOWNHILL SKIING. The basic up-and-down pumping motion of the knees is no threat to the athlete who's done enough off-slope conditioning. Dr. Avery Ferentz points out that the majority of problems crop up when the skier is out of shape, or when skiing beyond his or her capacity. An all-too-frequent refrain, he said, is "I knew I shouldn't have done that run but I had to keep up with my kids."
DANCE. Referring to jazz and ballet: A lot depends on the teacher and pupil. Dowd says if the matchup is good, and if the technique is appropriate for your body, dance can be a terrific exercise for the back. According to Gabe Mirkin, the high incidence of injuries you hear about among gymnasts and dancers comes from overstretching pushing beyond your range of motion.
GOLF. Beware the severe torsional movement involved in the golf swing. Ferentz says that for the golf-cart-driving weekender with a bit of a paunch and no abdominal muscle tone, a back injury is more than a remote possibility.