Running is one of the most popular forms of exercise worldwide. Due to the popularity, running also results in many injuries. These injuries occur from a multitude of factors, including joint loading and overuse. A recent study (Saragiotto 2014) asked runners what they felt were the main causes of their injuries in running, with runners responding:

    1. Not stretching
    2. Excess of Training
    3. Not warming up Lack of strength
    4. Wearing the wrong shoes
    5. Not Respecting the body’s limitations
    6. Foot type changes

Although the opinions about a running knee injury center around training, not many progress or monitor their volume systematically. In fact, many simply initiate a running program without much thought and progress at their own discretion. Those in the running world have heard varying opinions about training volume and have to safely add running volume. However, little research has been performed on training volume.

Nielsen (2014) gave 873 people neutral running shoes and monitored over 52-weeks. Of the 837 runners, 202 sustained one running knee injury. The injury rate was significantly higher for those who increased running volume greater than 30%, compared to those who increased running less than 10%. Unfortunately, this program did not randomly assign people to a high- or low-running volume program, making concrete conclusions impossible. However, these results do coincide with the results were see at our clinic.

5 Tips for Reducing Knee Injury While Running

  1. Increase Volume Slowly: As we just discussed, increasing the running by less than 10% decreases the risk of injury. Remember, there is plenty of time to add running mileage and many races, be smart, add slowly.
  2. Short Strides: Taking shorter strides decreases the stress on the patellofemoral joint. Willson et al. showed that a reduction in step length of at least 10% resulted in an average decrease of 16.3% in PF joint stress.
  3. Fast Feet: Having a quicker stride frequency also lowers the ground reaction force and joint stress. Increasing the stride rate by 10% actually decreases the joint stress at the knee (Lenhart 2014). Also, running with a faster cadence increases gluteal and hamstrings muscle activation, helping protect the lower leg from injury (Lenhart 2014).
  4. Slight Lean Forward: Many runners stand straight up, with a “neutral” spine, attempting to reduce spine loading and knee pain. However, recent research suggests a 14.1 degrees lean forward has the lowest patellofemoral joint stress compared to an extended or neutral spine position (Teng 2014). Don’t worry about the numbers, just lean slightly forward when running.
  5. Warm-up: Performing a dynamic warm-up prior to running helps increase body temperature, activate stabilizing musculature, and increase synovial fluid for smoother joint movement. Here is an example dynamic warm-up.

Summary

Although a running knee injury is common in running, it doesn’t make it an unsafe sport. If you are beginning a running program, start off with low volume and keep these 5 tips in mind for a safe transition to the sport, as an injury and trip to a physical therapist will slow down all progress!

References:

  1. Wirtz AD, Willson JD, Kernozek TW, Hong DA. Patellofemoral joint stress during running in females with and without patellofemoral pain. Knee. 2012;9:703-8.
  2. Lenhart RL, Thelen DG, Wille CM, Chumanov ES, Heiderscheit BC. Increasing runningstep rate reduces patellofemoral joint forces. Med Sci Sports Exerc. 2014;46(3):557-64.
  3. Saragiotto BT, Yamato TP, Lopes AD. What do recreational runners think about risk factors for running injuries? A descriptive study of their beliefs and opinions. J Orthop Sports Phys Ther. 2014 Oct;44(10):733-8. doi: 10.2519/jospt.2014.5710. Epub 2014 Aug 25.
  4. Teng HL, Powers CM. Sagittal plane trunk posture influences patellofemoral joint stress during running. J Orthop Sports Phys Ther. 2014 Oct;44(10):785-92. doi: 10.2519/jospt.2014.5249. Epub 2014 Aug 25.
  5. Nielsen RØ, Parner ET, Nohr EA, SØrensen H, Lind M, Rasmussen S. Excessive progression in weekly running distance and risk of running-related injuries: an association which varies according to type of injury. J Orthop Sports Phys Ther. 2014 Oct;44(10):739-47. doi: 10.2519/jospt.2014.5164. Epub 2014 Aug 25.

Written by Dr. G. John Mullen, DPT, CSCS