If you're a tennis player who thinks a game of doubles is healthful aerobic exercise, you're fooling yourself, a new study says. In fact, playing golf without an electric cart is better cardiovascular exercise.
According to the study by a sports medicine researcher, who matched cardiovascular effects of singles and doubles players, a doubles game provides only half the benefit of a singles game.
In all, said biologist Leland Morgans of the University of Arkansas at Little Rock, while doubles tennis may be a good social outlet, the game, in cardiovascular terms, consists of little more than standing in one place--an activity not destined to increase the body's oxygen intake.
To draw the conclusions, which are reported in the journal Physician and Sportsmedicine, the Arkansas research team hooked up 17 male tennis players (ages 17 to 44; from intermediate to advanced playing skills) to heart monitors worn on a belt. The men played 1-hour matches of singles and doubles while equipment tracked particulars of their cardiovascular performance.
Singles turned out to be fine exercise--causing the heart rate to rise to 61% of the maximum beating rate of which the muscle is capable. Various standards for judging cardiovascular benefit of exercise hold that, to be of any value, an activity must raise the heart rate to between 60% and 90% of the maximum.
Doubles was another story. Doubles players achieved only 33% of the maximum reserve heart rate, leading to the conclusion that "doubles . . . should not be considered an exercise regimen for developing fitness." In a telephone interview, Morgans contended doubles is popular among people who have a primarily social interest in tennis and who may make themselves think they are achieving a fitness goal.
"Golf (without a cart) would be fine, because you can get up to 65% to 70% of heart reserve," he said. "Doubles tennis is not as good as walking golf. Doubles players shouldn't delude themselves by saying: 'I'm getting exercise.' They really aren't getting very much."
New Back-Pain Remedy?
Injections of a mixture of three common chemicals combined with a one-time-only vigorous manipulation of the spine may be the most effective treatment for chronic, nagging low-back pain, a team of doctors at a Santa Barbara group practice reports.
And at the root of the claimed success of the new treatment, the head of the team said, is a comparatively new theory about why backs ache. The problem, said Dr. Robert Klein of the Sansum Medical Clinic, is rooted in damage to ligaments near the spine--not necessarily in muscle strain or the spine itself.
Klein concedes the cause-and-therapy theory is likely to be controversial and that the results of his treatment of an initial series of 89 patients might be dismissed out of hand, were it not for the decision by The Lancet, a prominent British medical journal, to publish the findings.
In the Lancet article, Klein and four other Sansum physicians reported on use of injections of a mixture of dextrose, glycerine and phenol, three chemicals widely used in medicine. After receiving an injection near the pain site, the patient was given so vigorous a spinal manipulation that it had to be given under a local anesthetic.
The spine adjustment must only be done once, Klein said, because "once we get everything in alignment, it stays aligned." Injections, Klein said, were given weekly after the initial treatment session. The injections are entirely different from the drug chymopapain, now widely discredited but touted sporadically in the last two decades as an alternative to surgery for damaged spinal discs.
Significantly, Klein said the Sansum Medical Clinic did not promote the new study or distribute press releases announcing its publication.
"The patients are pleased and they tell other people," Klein said. "As far as I'm concerned, this is revolutionary, but we are trying not to blow it out of proportion. We have to be very cautious in making claims. This is very controversial."