Why Do Some Recreational Runners Develop Overuse Injuries?
A recently published study suggests that many factors long believed to put runners at risk for overuse injury – such as flexibility, lower extremity strength, and weekly mileage – may not actually have anything to do with injury.
Elizabeth Barchi, MD, and Dennis Cardone, DO
Messier SP, Martin DF, Mihalko SL, et al. A 2-year prospective cohort study of overuse running injuries: The Runners and Injury Longitudinal Study (TRAILS). Am J of Sports Med. 2018 Jul;46(9):2211-2221. doi: 10.1177/0363546518773755. Epub 2018 May 23.
Messier et al performed a 2-year, prospective longitudinal observational study to examine risk factors differentiating uninjured recreational runners from those with a diagnosed overuse running injury. They identified 300 recreational runners who were:
- Between 18 and 60 years old
- Running a minimum of 5 miles per week
- Injury-free for the previous 6 months, with their current training regimen unaffected by any prior injuries
Study participants agreed to complete questionnaires at 6 and 12 months and respond to biweekly emails that asked them about injuries. At the start of the study, the runners underwent extensive baseline screening tests that included:
- Medical history
- Training history
- Injury history
- Anthropometrics, such as hamstring flexibility, Q-angle, and arch index
- Lower extremity strength testing
- Gait analysis
- Psychosocial questionnaire
The medical history, medication, and psychosocial questionnaires were repeated at the 6- and 12-month marks, as well as at follow-up visits for any running-related injuries during the study time period.
Two-thirds of the runners (66%) sustained at least 1 overuse injury; 56% of injured runners were injured more than once within the 2-year observational period. Most of the first injuries occurred within the first year of the study. The knee was the most-often injured site of the first injury, followed closely by the foot. Injuries that were considered traumatic (and not overuse) were not included in the data analysis.
Bivariate analysis identified 4 risk factors that significantly increased the odds of sustaining an overuse injury:
- Lower mental health-related quality of life, as measured by the Short Form Health Survey-12 mental component score
- Negative affect score, as measured by the Positive and Negative Affect Scale
- Gender: 73% of women and 62% of men sustained at least 1 injury
- Knee stiffness, which was seen in runners with higher body weights (80 kg or more)
With multivariate analysis, knee stiffness remained the only significant predictor of overuse running injury.
The authors found that flexibility, arch height, Q-angle, rear foot motion, lower extremity strength, weekly mileage, footwear, and previous injury were not significant contributors to overuse injuries.
Running is a popular physical activity, with more than 20 million recreational runners across the country. Many more will try running regimens for fitness. Running has been directly related to numerous health benefits. However, running has also been implicated in high rates of injuries, with some studies quoting a rate of up to 65% of runners reporting overuse injuries each year.
As clinicians, we are trained to counsel our patients on common risk factors that may lead to injury. The findings of this study suggest a change in how we counsel patients who engage in recreational running to help them avoid overuse injuries. The findings also suggest that many previously held risk factors – including flexibility, lower extremity strength, arch height, footwear, weekly mileage, and previous injury – do not put recreation runners at significant risk for overuse injury.
Elizabeth Barchi, MD, is an assistant professor with the Department of Orthopedic Surgery at NYU Langone Health – Orthopedic Hospital, New York, New York. Dennis Cardone, DO, is an associate professor with the Department of Orthopedics and associate professor with the Department of Pediatrics at NYU Langone Health – Orthopedic Hospital, New York, New York.
The authors have no disclosures relevant to this article.