First of all, many of you may be asking what is cadence? (I know I was when I first heard it) Well as defined by dictionary.com cadence refers to the beat, rate or measure of rhythmic movement. With regards to running, cadence is simply referring to the number of steps you are taking per minute. You may be thinking, “Why should I care about how many steps I take per minute, I’m more worried about surviving my
run rather than counting how many steps I take!”. Well over time numerous researchers have broken down running technique into its minute details to find ways to make it more efficient. Some of these studies actually evaluated cadence (or steps per minute) and its effect on running. What’s interesting is they found that the number of steps you take per minute does indeed influence your running technique, as well as injury rates.
One such study in 2011 showed that a 5-10% increase in cadence reduced loading of the hip and knee joints, shortened stride length, reduced vertical oscillation, and created less breaking forces (Heiderscheit, Chumanoc et al. 2011). If we think about it logically, this makes sense. The more steps we take, the shorter our step length (distance between each step). Because, in order to take more steps per second we have to reduce the distance of our steps. This subsequently causes our foot to land closer to our body, as we cannot move our legs as far out in front of us as we take more steps per minute. Imagine that you have to pick up a 15kg box off the ground. You would pick up the box up keeping it close to your body the whole time. Now imagine if I told you that you had to pick up the box while standing half a meter away from it and you had to keep your arms outstretched the whole time. The second situation is much more difficult. Something being further from our body requires much more energy and balance and is typically more difficult to accomplish. The same principle
applies to our running technique. The further my foot lands in front of my body the more energy I have to expend to keep it there. Similarly, because my foot is further away from my body it makes it more difficult to effectively transmit the forces from the ground up through my entire body, and typically the lower body joints (e.g. lower back, hip and knee) take an increased load as a result. By increasing our steps per minute, we force ourselves to bring our foot closer to our body in order to take these increased steps. Subsequently, this allows us to more evenly disperse the forces from the ground through our entire body instead of just the lower limb joints (thereby decreasing injury risk) and save energy as we have improved balance and control.
So how many steps per minute should I be taking? The general ballpark figure is 180 steps per minute. Why 180? Well there are a few reasons. Firstly, observational studies of Olympians showed that a cadence of 180 was optimum in running all distances from 1500m to a marathon. Secondly (and perhaps more interesting) a study evaluated the natural resonant frequency (the rate at which something wants to vibrate at) of muscle in a tendon unit (Dean and Kuo, 2011). The natural resonant frequency turned out to be 3Hz (Hz = Hertz = cycles per second). If we extrapolate this a little: 3Hz = 3 cycles per sec x 60 seconds = 180 cycles/min. There’s that magic 180 number. So, if we take 3 steps per second that works out to 180 steps per minute. So theoretically, running at this cadence allows us to maintain the natural vibrations of our Achilles tendon. This in turn allows us to save energy as we are using our Achilles tendon's “free” vibratory energy, instead of having to generate new energy with each step by contracting our muscles. All in all, leading to a more efficient running technique.
Hopefully you now have a better understanding on what cadence is and what benefit is can have on your running technique. So, what should you do about it? Well, next time you go for your run, count how many steps you take during a one-minute period and report back. How many did you get? 150? 160? 170? Chances are that you most likely did not hit 180 steps per minute. If you did, excellent, you rock! If not, don’t be disheartened. You’re not alone, in fact studies have shown that most recreational runners have a cadence that is too slow (Giandolini and Arnal, 2013). “Well then, what should I do to increase my cadence?” If you’re anything like me your phone is always close by. So, grab your phone and go to the app store and download a metronome app (I use an app literally called ‘Metronome’, its free and does the job). Now, the next time you go for a run just set the metronome to your new improved cadence and ensure you are taking a step for every beat on the metronome. However, it is very important that I note a few things here. Firstly, your individual running technique is a unique and highly coordinated muscular pattern. Any change to your default technique will result in an increase in energy until your body has a chance to adapt to the new loads generated by the change in technique (typically takes 4-6 weeks). Because of this, any changes we make to our running technique must be incorporated slowly (transition period), so they can be properly and safely integrated. For example, run with your new cadence for 500m (e.g. 1 minute) then turn the metronome off and run how you would normally. Do this for all your runs this week. After your first week of this new running technique, increase the distance (or time) with your cadence to 750m (90 seconds) before reverting to your 'normal' running style. This slow integration ensures that we incorporate these changes safely. Eventually you’ll get to a point where you will be able to complete your whole run with your new technique. On the other hand, if you wake up one day and decide to completely change your running technique (without a transition period) you will use more energy and place yourself at a higher risk of injury. Now you might have one final question: “How much should I increase my cadence by”. Well, when increasing your cadence, you should not increase it any more than 10% from your current cadence at any one time. So, if your base cadence was something like 150, an increase in 10% will only bring you to 165. Once you have run at this new cadence for a few sessions (ensure we are integrating it slowly and safety as stated previously) increase it again by 10%. Repeat this until you reach 180. Once again, this is to ensure that we are making lasting improvements to our running technique and doing it safely.
If you have any questions or want to let me know how you went changing your cadence, feel free to email me at rsecoulidis@gmail.com
Ronald Secoulidis
BHSc/BAppSc(Chiro)
References:
Heiderscheit, B. C., Chumanov, E. S., Michalski, M. P., Wille, C. M., & Ryan, M. B. (2011). Effects of step rate manipulation on joint mechanics during running. Medicine and science in sports and exercise, 43(2), 296.
Dean, J. C., & Kuo, A. D. (2011). Energetic costs of producing muscle work and force in a cyclical human bouncing task. Journal of Applied Physiology, 110(4), 873-880.h
Giandolini, M., Arnal, P. J., Millet, G. Y., Peyrot, N., Samozino, P., Dubois, B., & Morin, J. B. (2013). Impact reduction during running: efficiency of simple acute interventions in recreational runners. European journal of applied physiology, 113(3), 599-609.