Nov. 29, 2010 (Chicago) -- Contrary to what’s been taught, you can run through pain.
So say researchers who used a 45-ton mobile MRI unit to follow runners for two months along a 2,800-mile course to study how their bodies responded to the high-stress conditions of an ultra-long-distance race.
"The rule that 'if there is pain, you should stop running' is not always correct," says study leader Uwe Schutz, MD, a specialist in orthopaedics and trauma surgery at the University Hospital of Ulm in Germany.
If your pain is caused by muscle inflammation, it may be possible to continue running without risk of further tissue damage, he tells WebMD.
But if you have a stress fracture, the pain may not go away and you may be at risk for further damage, Schutz says.
Andreas Falk, of Sweden, who ran in the ultra-race, is a case in point. After suffering a muscle injury, he tells WebMD he had to walk instead of run for five days, literally crying four to five hours on the first few days due to the pain.
"But I just kept going; I could feel the pain decreasing each day," says Falk, who is fine today.
The problem, Schutz says, is it's not easy to distinguish between the pain of a stress fracture and that of severe muscle or tendon inflammation. That may require a trip to the doctor.
Loss of Visceral Fat
Use of the mobile MRI allowed the researchers to acquire huge amounts of unique data regarding how endurance running affects the body's muscle and body fat, Schutz says.
He's not suggesting you need to run 2,800 miles -- the equivalent of over 106 marathons -- to benefit. "Much of what we have learned so far can also be applied to the average runner," Schutz says.
The TransEurope-FootRace 2009 took place from April 19 to June 21, 2009. It started in southern Italy and traversed through the Alps, across the water to Sweden, finally winding down in the North Cape in Norway.
Forty-four runners agreed to participate in the study; 22 underwent a whole-body MRI exam every three or four days, totaling 15 to 17 exams over a period of 64 days. Urine and blood samples were collected regularly.
Results showed that runners lost an average of 5.4% body volume during the course of the race, most during the first half. Loss of body volume correlates with loss of body weight, says RSNA spokesman David Levin, MD, of Thomas Jefferson University Hospital in Philadelphia. He was not involved with the study.
The runners lost about 11 pounds of fat and 2 1/2 pounds of muscle. Importantly, loss of "bad" visceral fat loss occurred much earlier in the run than expected, Schutz says.
Visceral fat is linked to an increased risk of cardiovascular disease, Levin says. "Running is a great way to lose body fat," he tells WebMD.
One surprising finding was that despite the daily running, the leg muscles of the athletes actually degenerated because of the immense energy consumption, Schutz says.
This study was presented at a medical conference. The findings should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.