Benefits of Step Rate Manipulation in Running
Robyn Smith MSPT, SCS
During running, form matters! And there’s been ample research focusing on running injuries and injury prevention. Over the last 10 years, one area that has received a lot of attention is step-rate, or cadence manipulation. Research has shown large impact forces occur between our foot and the ground when we over stride. This means when our foot hits the ground too far in front of our body’s center of mass, we create extra unnecessary force on our body. This typically happens when we are too upright and our step rate is too low. Let’s take a look at the same runner at a constant speed on a treadmill. The picture below shows when the runner is hitting the ground 160 times in one minute compared to 176 steps per minute (a 10% increase in step rate).
Take note of a few things in both examples:
1) The heel is hitting the ground much further from pelvis/trunk in the first picture
2) The shin angle is further from the vertical position
3) The toes are more aggressively pointed upward, meaning the ankle is more dorsiflexed.
The only cues given here were to stay at the same speed and try to increase the step rate by 10% from where they were currently by listening to a metronome beep at the new rate.
Initial impact forces and the position of the shin and foot at initial contact to the ground have shown to play a role in injuries, especially knee and shin pain. The further the foot lands in front of the body, the more force is found going through the knee and lower leg. Runners that are experiencing pain in these areas often notice an immediate decrease in their pain by just increasing their step rate by 5-10% from their current/preferred step rate. Research has shown the biggest improvements in impact forces are in this range (depending on how far from “ideal” it is). Many articles will say that 180 steps per minute is the magic number. This is a LOOSE guideline. The “perfect number” really depends on how the runner currently looks while running based on how far the foot is in front of the runner and how bouncy vertically the gait is.
Without doing a gait analysis on yourself, the best bet is just to count where your natural cadence is currently. Then based on a goal of 180 steps per minute, if you are well below this target, try to increase your rate by 5-10% while running at the same speed and take note of how your body feels. At first, this will feel foreign as every new change in your running form takes some time and practice to normalize. Some runners may already have a quick step rate; however, most novice runners can improve this, overall helping them staying injury free. This is easiest when practiced on a treadmill, because you can keep the treadmill at the same speed, but change your cadence. Downloading a free metronome app to your phone and matching the beat with your steps is a simple way to implement this change. Once you get the hang of this, you can turn on your music and recheck your cadence at different intervals in your run.
Interesting facts in research regarding cadence/step rate manipulation:
· Those who suffer from shin splints or tibial stress fractures show a positive shin angle (lower leg further from the vertical at initial contact).
· The forces on the back side of the patella are reduced significantly from increasing step rate by 10% from your preferred rate.
· There is better muscle activation and strength in the hip when your foot hits the ground closer to your center of mass (which happens with increased step rate).
· There is improved leg alignment (knee doesn’t collapse inward as much) with a 10% increase in step rate from preferred.
· Even though you hit the ground more times per mile, there is still less force overall in the lower leg and knee with increased step rate.
It’s fun to run and not think about ANYTHING, but it’s more fun to run pain-free! This is just one of several things you can try if you are working on injury prevention with running, or constantly having nagging knee or shin pain. So, if you’re looking to get out there, the Gobble Wobble 2020 is guaranteed to be one of the best virtual races of the year! Get out there, support Gazelle Sports, Kids Food Basket and Hulst Jepsen Physical Therapy. This year, make memories for your Thanksgiving holiday with a new family tradition of running the virtual Gobble Wobble, and then fill your stomach with all of the good feelings of post-race carbs while forgetting about the 2020 race season for a while. Don’t forget to sign up for race at www.gobblewobblegr.com!