Runners over the age of 30 are more likely to incur injuries. They can protect themselves against this by doing strength training and keeping their fat percentage low. Epidemiologists at the U.S. Army Public Health Center write about this and more in the Journal of Strength and Conditioning Research.
StudyEach year somewhere between 35 and 65 percent of all runners incur an injury, and those in the army are no exception. About a quarter of all the injuries that soldiers face are a result of jogging or running. The researchers carried out a survey among 4236 soldiers to identify factors that can help prevent this.
AgeAfter the age of thirty, the risk of injury increases, the researchers discovered. That's not surprising. Tissue becomes weaker with age.
Body weightThe higher the soldiers' BMI, the greater their risk of injury. That would suggest that runners can protect themselves against injury by keeping their fat percentage down. Okay, okay, that's not surprising either.
KilometresThe more kilometres the soldiers ran each week in a group - with their unit, and probably under the inspiring leadership of a somewhat dominant sergeant - the greater the chance of injury, as is shown in the figure on the left below.
The researchers found that the relationship was the opposite when they looked at the number of kilometres the soldiers ran on their own. In this case, the risk of injury decreased the more kilometres the soldiers ran, as the figure on the right above shows.
So the distance run protects runners against injuries, but they must be able to run in a way that is good for them. If you run in a group, you have no say over the route, the time and speed. And that makes injuries more likely.
Strength trainingStrength training was the strongest protective factor that the researchers found. Soldiers who did strength training three times a week halved their likelihood of developing running injuries.
Conclusion"In a population of exercising young adult males, those who ran further for personal training exhibited higher levels of aerobic fitness", the researchers wrote. "It appeared that these higher levels of fitness were more protective than the higher mileage was injurious."
"Resistance training equal to or more than 3 times a week also appeared to add a protective effect for these physically active young men."
"These findings suggest that for general fitness a combination of aerobic and strength training will enhance fitness and reduce running-related injuries."