By The Numbers: Injury Risk In Runners

Running is a tremendously popular sport, with approximately 40 million people running regularly in the United States. This is not particularly surprising given all of the well-documented health benefits of this form of physical activity. Unfortunately, running also carries with it a high rate of injury, with up to half of runners experiencing an injury on a yearly basis. While many factors play into this high rate of injury among runners, two primary risk factors stand out: history of previous injury and overtraining. With these in mind, here are some important numbers to be aware of when designing or following a training program.

• 40

  • Multiple studies have shown that running greater than 40 miles per week significantly increases the risk of injury

• 13

  • Runs longer than 13 miles should be done no more than once every 14 days, as exceeding this significantly increases the risk of injury

• 10%

  • While this number is hotly debated due to inconsistent evidence, it is generally accepted that increases in weekly training mileage should not exceed 10% per week, as doing so increases the risk of injury

• 6

  • Running 6 or more days per week significantly increases the risk of injury

• 4-5

  • With respect to injury, most regular runners do best when training no more than 4-5 days per week, with at least 1 day of rest and 1-2 days of cross-training built in

• 2-3

  • Runners should limit themselves to no more than 2-3 marathons per year

Keep in mind that these are numbers from a variety of prospective and retrospective studies on specific populations of runners and may not directly apply to you. However, they do help provide metrics for you to use when evaluating your own training program, whether it be for your first 5k or your attempt to qualify for the Boston Marathon. In general, most training programs should progress slowly, incorporate rest days, and include cross-training exercises that promote improved strength and stability. It is difficult to enjoy running when injured so keep these numbers in mind, as they may help you lower your overall risk of injury when training for your next race.

Run safely!

-Grant Hennington, DPT

Do Your Part: Trail Etiquette

A great aspect of living in the Pacific Northwest is the sheer amount of easily accessible hiking trails. You could try, but it might take you two lifetimes to hike every trail in Washington. With summer on the horizon and our stay-at-home orders are easing, many of us will start emerging from our homes in order to hit the trails. If this includes you, please remember to follow proper trail etiquette to help us still maintain appropriate social distancing with increasing trail usage. 

YIELDING THE RIGHT OF WAY: Horses are huge, so yield to horses, period. Step off the downhill side of the trail, stop, and speak calmly. When approaching another hiker, uphill traffic should generally be given the right of way. If a convenient spot is available, pull over and allow the uphill hiker, runner, or cyclist to pass. Do not continue to move forward once off the trail, as this leads to the creation of multiple trails and increases the impact on the land.

ANNOUNCE YOURSELF: Say “hello” to fellow trail users. Be courteous, respectful, and announce your presence if approaching someone from behind. And please don’t yell “BOO!” It generally doesn’t go well and frightens people.

SLOW DOWN: When bikers and hikers share the same trail, patience is key. The most important tip for the survival of a trail is traveling at a safe and appropriate speed. Both foot and bicycle users must travel at a speed conducive to the trail design. Washboard trails and extra wide or multiple parallel trails are caused by poor speed control. Negative encounters with fellow trail users can be reduced by knowing your safe speed and being aware of your surroundings.

LEAVE NO TRACE: Pack out what you pack in. If you see trash on a trail, pick it up. Make your parents proud.

RESPECT TRAIL CLOSURES: Trail closures apply to everyone and are mandated for a reason. Most of the trails with group size restrictions are narrow, steep, and inherently dangerous for high volume use.

STAY ON THE TRAIL: If the trail is snowy or icy, wear traction devices. If your shoes or mountain bike tires sink deeply into the mud, you should not ride that particular trail until it dries out. Do not create a new trail by avoiding mud, puddles, or other trail users. 

SUPPORT OUR TRAILS: Give back to our local trail network. The Washington Trail Association and Evergreen Mountain Bike Alliance are great local associations that help maintain and fund our trail systems.

Hope to see you out there!

-Tucker Schonberg, PT, OCS

An Ounce of Prevention: Reducing the Risk of Ankle Sprains

A running joke in Seattle is that summer doesn’t start until July 5th, which therefore means prime hiking season is now upon us. Exploring the mountains and alpine lakes of the Pacific Northwest can be an excellent form of exercise, bringing with it numerous benefits to your musculoskeletal and cardiovascular systems. But with those benefits also comes the risk of injury, with ankle sprains being a common culprit. In fact, ankle sprains make up approximately 45% of all sports-related injuries in the United States. While most ankle sprains will heal over the course of 2-8 weeks, 73% of individuals who have sustained an ankle sprain once are likely to sustain another ankle sprain in the future. Fortunately, the risk of ankle sprains can be reduced via injury prevention programs. In fact, those who have sustained an ankle sprain in the past benefit even more from these injury prevention programs, experiencing a greater reduction in risk than those who have never sprained an ankle. However, the overall risk of ankle sprains is still higher in individuals who have a history of an ankle sprain. The best predictor of a future injury is a past injury. We cannot change the past, but we can alter the future by performing targeted exercises at the ankle joint.

So what do these injury prevention programs look like? The primary goal is to improve ankle stability via balance/proprioceptive exercises, which are the gold standard for reducing the risk of ankle sprains. Standing on one foot with your eyes open on flat ground is a solid baseline, for which you should be able to balance for 60 seconds without having to catch yourself. If you can do this without much of a challenge, a simple progression is to close your eyes, which will make the exercise significantly more difficult. Our vision is one of three systems to contribute to our sense of balance and typically the one we rely on most. So, when we close our eyes we are down to two systems and are therefore less efficient at maintaining our balance. Once this is mastered, one could advance to performing single leg balance with motion on the opposite side of our body, further challenging our limits of stability. Here is an example:

Single Leg Balance Progression Video

Balance exercises like these can be performed every day in order to reduce the risk of ankle sprains when hiking, backpacking, or trail running. Perform balance exercises barefoot in order to make them more challenging. As always, all exercises should be pain free and you should get approval from a healthcare provider before beginning a new exercise program following an injury. Once cleared, find a safe and quiet place to stand on one leg and test your limits of stability.

-Grant Hennington, DPT

Quick Guide To Improve Running Efficiency And Reduce Injury Risk Via Running Cadence

Here in the Pacific Northwest, we have many road and trail running races scheduled in the summer and fall months, as the rainy season subsides for blue skies. No matter if you are planning on running a 5K, 10K, half marathon, marathon, or even ultra marathon, you may want to consider evaluating your running cadence before starting your training program. Running cadence is a measure of the number of steps you take per minute while running, with an ideal rate falling between 160 and 180 steps per minute. Not only has this range been linked with improved running efficiency/economy, but it has also been linked with a reduced rate of injury. To measure, simply count the number of steps you take while running at your training pace for one minute, or count the number of steps you take while running at your training pace for 30 seconds and multiply by two. If you are on the low end of the range or fall below 160 steps per minute, you may be over-striding, putting yourself at an increased risk of developing a nagging overuse injury, such as Patellofemoral Pain Syndrome, which will negatively impact your training. Try measuring it for yourself during your next training run and see where you stack up!

-Grant Hennington, DPT