STEAMBOAT SPRINGS, COLO. – The youth obesity crisis has a huge and underappreciated flip side: An epidemic of overuse injuries in heavy kids who’ve been told to start exercising without receiving any informed guidance.
"A lot of times we’re turning to sports and exercise in the battle against obesity, and it’s backfiring," according to Dr. Paul R. Stricker, a pediatric sports medicine specialist at the Scripps Clinic in San Diego.
"We hear about overweight all the time in the media, but overuse injuries are also an epidemic in my world. They are rampant. We’ve got millions of kids every year with overuse injuries from doing too much, too fast after a lifetime of inactivity," he said at the meeting.
"Obese youth are being told to ‘just start jogging,’ and a few weeks later they’re ending up in my sports medicine clinic. And they’re already defeated," said Dr. Stricker, a past president of the American Medical Society for Sports Medicine who served as a U.S. team physician at the Olympics.
"The experience of camaraderie and accomplishment of being on a team can absolutely do wonders for [obese] children."
The approach to exercise among previously sedentary overweight and obese youth needs to be quite different from that taken with active kids experienced in sports. The start is more gradual and cautious. The initial emphasis is placed upon stretching, strengthening, and conditioning in order to allow the body time to adapt to new demands.
Dr. Stricker likes to start these kids off with non-impact exercises, such as swimming, water aerobics, bicycling, and low-impact dance or walking. Supervised strength training is a particularly good way for these heavy kids to get on board the life-long exercise train.
"They can see real progress very quickly. It really gets them motivated, and the increased muscle mass is helpful because it brings an increased metabolic rate, which promotes weight loss," he explained.
If a heavy, sedentary kid wants to take up a team sport – be it wrestling, football, or a non-contact sport – the message from coaches and parents ought to be that the first season should be a learning experience in which the emphasis focuses on catching up in terms of sport skills. The new player might not see much game time this year, but next year could be different.
"The experience of camaraderie and accomplishment of being on a team can absolutely do wonders for these children," according to the pediatrician.
Overweight and obese kids face multiple challenges in taking up exercise. Not only do they have a lengthy history as couch potatoes, but their diet is typically quite poor. And while heavy kids look like they’re skeletally mature because of their size, in fact they’re often late bloomers. Their open growth plates predispose to fractures.
Among the most common overuse injuries Dr. Stricker encounters in overweight kids who’ve taken up exercise are:
• Patellar maltracking. Heavy children often have knock knees, shortened and inflexible hamstrings and quadriceps, and weak patella muscles, all of which promote patellar maltracking laterally. The extra weight being carried around increases the patellar load, further predisposing to kneecap pain and maltracking. Affected kids find running, jumping, and going up and down stairs particularly problematic.
• Foot overpronation. Overweight youth typically have flattened arches. This results in biomechanical problems, including tibial rotation with resultant excess forces being transmitted through the medial side of the lower leg. The faulty biomechanics, coupled with excess weight and a rapid increase in physical activity, results in tissue overload. Shin splints, foot pain, and patellar maltracking are common.
"It’s very important for us to evaluate below the knee, to look at the feet and say, ‘Hey, you might benefit from an insert,’ " Dr. Stricker said.
He virtually never refers these heavy kids with flattened arches to a podiatrist for a $400 pair of custom orthotics. It’s a waste of money. Over-the-counter inserts costing $30-$35 work as well or better. Avoid the soft, floppy, spongy variety in favor of inserts comprised of a thin layer of cushioning over hard molded plastic; Superfeet and Spenco make good-quality products, he said.
• Heat sickness. Kids in general are more vulnerable to heat injury than adults. They have a higher metabolic rate as well as a greater body surface to mass ratio. They have a poor thirst drive. Plus, sweat glands are typically immature and fewer in number in youth below ages 12-14 years. Their smaller blood volume makes it more difficult to dissipate heat.
All of these issues are accentuated in overweight kids. Moreover, since they are new to exercise and sports, their inefficiency of movement results in generation of extra heat, Dr. Stricker explained.