Lighting Up May Increase Exercise-Related Injuries
March 22, 2000 (Atlanta) -- Smokers may be at higher risk for
exercise-related injury, according to a report in the April issue of the
American Journal ofPreventive Medicine. Experts say new data
suggest that smoking has an adverse effect on the repair of muscle, bone, and
Because smoking has been identified as a risk factor for physical injury,
researchers explored its effect on exercise-related injury during basic
military training. More than 2,000 male and female recruits completed a
questionnaire about smoking, exercise, and injury. Body mass and physical
fitness were also assessed before the training program started.
The data showed that those recruits with a history of smoking, prior to
smoke-free basic training, suffered significantly more injuries than
nonsmokers. Even when the researchers controlled for age, weight, and fitness
level, those with a smoking history were 1.5 times more likely to be injured
than those who didn't smoke.
Some of the detrimental effects of smoking are immediate. "Soldiers and
others don't have to wait 10 to 30 years to experience the effects of
smoking," says lead study author John Gardner, MD, DrPH, a medical
epidemiologist and professor of preventive medicine at the Uniformed Service
University of the Health Sciences in Bethesda, Md. "Some effects occur at
an early age, have immediate consequences, and last at least several weeks
after smoking cessation.
"Subjects with a smoking history were less active, less fit, and had
more previous injuries. And so behavioral differences explain the findings in
part," Gardner tells WebMD. "But it's also likely that smoking
interferes with the process of tissue repair, making musculoskeletal tissue
more susceptible to trauma and overuse."
Research supports this theory. "There's evidence that smoking interferes
with both wound healing and tissue repair," says Bruce Jones, MD, MPH, a
medical epidemiologist with the division of unintentional injury at the CDC.
"It's also been shown that bone union is delayed in smokers with leg
fractures and that middle-aged smokers have less bone density." Jones, who
provided WebMD with an objective assessment of this study, says that many
studies link smoking and injury, but the biological mechanism behind this link
"Because both experimental and clinical studies link smoking with
impaired tissue healing, further investigation is warranted," says Gardner.
"One limitation of this study is that the findings rely on self-reported
data. But several large military studies are under way to confirm these
The study was supported by the U.S. Army Center for Health Promotion and
- People who smoke may be at higher risk for exercise-related injuries,
according to a new study.
- Behavioral differences may partly explain this effect, as smokers are more
likely to be less active and less fit compared to nonsmokers.
- Previous research has shown that smoking also interferes with repair of the
muscles, bones, and connective tissue.