Running Mechanics: Improving Cadence (Part 2)

Running Mechanics: Improving Cadence (Part 2)

In my last blog post, I touched on exactly what stride frequency or cadence is (I use them synonymously in this post). The next question is how do I bring my current stride frequency (preferred stride frequency) closer to my ideal (optimal) stride frequency? The first thing you need to assess is whether or not you actually need to change your stride frequency. I’m a firm believer of, “If it ain’t broke don’t fix it”, but if I feel it’s necessary for a client there are steps I can take. An easy way of determining whether or not you need to change your stride frequency is having a friend run next to you or stand stationary while assessing your running gait, or perhaps even video yourself running and then look out for the following common errors:

 

  1. When your foot hits the ground, is your tibia (shin bone) perpendicular to the ground or does it have a large positive angle (i.e. knee is well behind the ankle).
  2. When your foot hits the ground, is your knee locked out, or slightly softened (i.e. is your leg completely straight or is there a slight bend in your knee)?
  3. Does your foot land well in front on your centre of mass (i.e. well in front of your hips), or does it land underneath your hips?

 

Many runners, especially recreational runners and runners who have not had formal training have a tendency to overstride. Note that over striding has nothing to do with your foot strike pattern (heel strike, midfoot or forefoot), but rather if your tibia has a large positive angle, if your knees are locked out on landing, or if your foot lands well in front of your centre of mass – then you are likely guilty of over striding. Two practical tools to tell whether you are over striding are to freeze frame the landing/initial contact phase of your running gait and draw a vertical line from your lateral malleolus (ankle bone) upwards. If that line is in front of your hips, you are likely over striding (Souza, 2016). Alternatively you can use the same freeze frame and determine the angle between your shin bone and the ground. A neutral or close to zero degree angle is associated with good running form (Ting-Ting, 2015). As mentioned in my previous article, there is plenty of evidence to suggest that increasing your cadence can reduce the impact substantially that your bones, muscles and joints experience – something which is heightened in people who overstride. So how do I improve my cadence?

 

Here’s where I’d like to make two distinctions: A) you can improve the frequency of your stride in terms of quantity and B) you can improve the quality of your strides. Improving both of these factors will aid you in improving your running cadence, and doing so safely and effectively. Let’s start with the super fancy/technical ways of improving your stride frequency. In an analysis of current gait retraining methods, Ting-Ting (2015) analysed different systems/technologies available to runners to change their gait techniques and summarized them as follows:

 

  • Visual training – using mirrors in a lab/treadmill environment, verbal feedback, coach/trainer’s feedback, post-run video analysis, and 3D motion analysis.
  • Technologies: soft strain sensor, goniometer, inertial measurement units (IMU), and proximity sensing.

 

Ting-Ting (2015) notes that current technology aimed at gait retraining has many flaws in that it is either;

 

  • Not very portable (limited to lab settings/treadmill);
  • Extremely expensive (current IMU “suits” such as the Xsens Biomech System costs a staggering $75,000);
  • Can limit your actual movement while running (such as goniometers and soft strain sensors).

 

As such, Ting-Ting (2015) modeled an IMU technology that fitted to the shin like a compression sleeve and measured the tibia angle when contacting the ground while providing live feedback to the runner via a display unit on the wrist. Through his study, Ting-Ting (2015) showed that there may be a cost-effective tool arriving on the running market very soon that will allow runners to change their running cadence and gait without the requirements of a coach, or expensive technologies. Until then – here are some easier, more practical ways of improving your cadence.

 

Firstly, you need to determine your current preferred cadence, which can be done relatively easily. My first concern when I decided to improve my cadence was, “When I run different types of training runs or lengths of races, my cadence varies already – surely this is going to be an impossible task?”. It is true that your cadence will vary based on the distance and intensity that you are running. I’ll make use of a hyperbole to demonstrate this: Tyson Gay can take around 45 steps in a 100m sprint of 10 seconds which equates to 270 steps per minute – most distance running coaches will tell you that anywhere over 180 steps per minute is pretty good, and most recreational runners have a cadence of somewhere between 150-170 steps per minute. It’s clear then that the shorter the distance and the faster the pace, the more strides you will take per minute. Therefore, the goal of improving your cadence should be improving your cadence in general and I advocate doing that by targeting specific sessions or training days which are focused on improving cadence. This is particularly critical information for trail runners who often run different running routes every time they train, and if you run different routes at different speeds every time you train, your focus shouldn’t be on improving your cadence on that specific route, but improving your cadence in general.

 

Coming back to my statement of, “you need to determine your current preferred cadence” – this is what I would advise. Go for a run on a set route (something which you can replicate easily) which is preferably flat. Run at the pace that you find comfortable, or perhaps at the pace that you would run on a typical race day. Count how many steps you take in a minute (some watches will be able to tell you your cadence, but otherwise you can manually count your amount of steps in 15 seconds and times it by four). It is important not to manipulate your stride here already and to just run at what feels natural for you. What I am trying to achieve with the athlete here is having one session a week where we work on cadence improvement. If you stride at 160 steps per minute for example, you can then try and complete the same run next week, but with a 5% improvement in cadence (5% of 160 is 8 so aim for 168 strides per minute next week). Counting strides however can be seriously tedious so I advocate making yourself a playlist of songs that have a beat count of 168 beats per minute, or using a metronome set to 168 beats per minute. This approach of using auditory stimulus to adapt cadence is used by almost all research studies who try and manipulate running cadence (Bood et al. 2013; Hafer et al. 2015; Hafer et al. 2016; Wellenkotter et al. 2014).

 

Two practical ways to use auditory stimulus is to go on a website like jog.fm where you can type in the beats per minute that you are aiming to stride at (I.e. Taylor Swift’s Shake It Off has 160 beats per minute, and Imagine Dragons’ Thunder is 168 beats per minute), and then download all of the songs at your goal cadence and make a playlist to listen to while running and stepping once on every beat. The alternative is to use a metronome which you can also download or even find an app for and run to the ticking of the metronome. The key when doing cadence re-training is to start slow. As I said in my previous article, most recreational athletes stand to gain from increasing their cadence by 5-10%. The idea of introducing this one cadence re-training session per week is to slowly but surely retrain your legs to become comfortable at faster cadences. A rewiring of neuromuscular circuitry takes place when you begin these cadence sessions – but it takes place over time. The re-training that you are doing in this session will hopefully start to transfer over to you general running gait/cadence so that your cadence picks up over all types of runs, regardless of the route, distance or pace you are running at. Once you are satisfied that you can run at your optimal cadence in this particular session, you can try and carry over the same methodology into other runs in your training week. Hopefully the skills that you learn in your few cadence re-training sessions per week will begin to transfer into all of your running. Remember that cadence re-training takes time and don’t try and change too much too quickly – rather take it one session at a time.

 

This transference was observed by Hafer et al. (2015) who found that after 6 weeks of increasing running cadence by 10% (from previous preferred stride frequency), runners maintained their running efficiency (economy), and had several favourable changes including a shortened stride length, decreased hip adduction angle and decreased vertical loading rate (decreased forces acting up the leg). Hafer et al. (2015) define this as a “carryover effect” of cadence retraining and suggest there is enough evidence that after a short, 6 week, intervention where 50% of a runners’ training volume is performed at the new ‘optimal’ stride frequency, positive changes can be made in running cadence.

 

My final tip with cadence re-training has to do with the mass-spring model and the quality of your stride. The mass-spring model introduced by McMahon and Cheng (1990), describes the leg as a linear spring model based on ground reaction forces and centre of mass displacement resulting in a bouncing movement pattern (Hunter & Smith, 2007). The efficiency of this “spring” (your leg) is determined by how stiff it is – known as leg stiffness – which is determined by tendon, joint and muscle stiffness. It is widely accepted that leg stiffness and stride frequency are related (Hunter & Smith, 2007), and that a higher leg stiffness is related to a greater stride frequency. As such, if runners can take advantage of improving their leg stiffness, the result will be a positive adaptation in stride frequency quality with a resultant improvement in stride rate. In a later post I will discuss a variety of different methods of improving leg stiffness including resistance/strength training and plyometrics. If you manage to incorporate both a cadence retraining element as well as improve your leg stiffness you will see a marked resultant improvement in cadence rate as well as improve your resilience against vertical forces acting on the body which means fewer injuries and better performance!

 

Next time I am going to be keeping things running mechanics related but turn my focus to challenging some stereotypes with running mechanics. I feel like this topic is quite subjective, and as such it is often the person who shouts loudest or has the strongest opinion that ends up shaping our view on running mechanics. Hopefully I’ll be able to present enough evidence to change your mind about some stereotypes you may have heard about (like all runners should have a cadence of 180spm or else they’re a terrible runner!). Until then enjoy your training and let me know if you decide to do some cadence re-training and how it goes!

 

References:

 

Bood, R. J., Nijssen, M., van der Kamp, J., & Roerdink, M. The power of auditory-motor synchronization in sports: enhancing running performance by coupling cadence with the right beats. PLOS ONE. 8(8) p. 1-8.

 

Hafer, J. F., Brown, A. M., Demille, P., Hillstrom, H. J., & Garber C. E. (2015). The effect of a cadence retraining protocol on running biomechanics and efficiency: a pilot study. Journal of Sports Sciences. 33(7) p. 724-731.

 

Hafer, J. F., Silvernail, J. F., Hillstrom, H. J., & Boyer, K. A. (2016). Changes in coordination and its variability with an increase in running cadence. Journal of Sports Sciences. 34(15) p. 1388-1395.

 

Hunter, I., & Smith G. A. (2007). Preferred and optimal stride frequency, stiffness and changes with fatigue during 1-h high-intensity run. European Journal of Applied Physiology. 100 p. 653-661.

 

Souza, R. B. (2016). An evidence-based videotaped running biomechanics analysis. Phys Med Rehabil Clin N Am. 27(1) p. 217 – 236.

 

Ting-Ting, L. (2015). A wearable gait analysis system for over striding in runners.

Wellenkotter, J., Kernozek, T. W., & Suchomel, T. (2014). The effects of running cadence manipulation on plantar loading in healthy runners. International Journal of Sports Medicine. 35 p. 779-784.  

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