To start the week, we welcome back the thoughtful talents of Mile27’s Andy DuBois. In this article, Andy argues that most runners spend almost 100% of their training time actually running, based on the mistaken belief that if you want to become a better runner then you should simply run more.
He believes that the reason this is misguided is that our running technique and efficiency is dependent on the strength and flexibility of the muscles, tendons, ligaments and fascia of our body. If we take this as set in stone and unchangeable then running more is the only way to improve your ability to run. However this is not set in stone, we have the ability to change the strength and flexibility of our body and therefore change the way we run. Take it away Andy…
Run faster with less effort
One aspect of running that many people ignore is the elasticity of our tendons and how we can use this to our advantage. If you watch elite runners you will notice they seem to float across the ground barely touching the surface whereas slower runners tend to land heavily and have to propel themselves from the ground with great effort.
Elite runners have short ground contact time which maximises the use of elastic energy whereas the long ground contact time of the slower runners means elastic energy is lost and can’t be reused.
What is Elastic Energy?
Elastic energy is the energy absorbed by the muscles, tendons, ligaments and fascia of the body when they are subjected to a dynamic load. In running this occurs in two places, when we land and when the trailing leg finishes extending behind us and starts coming forward.
Upon landing the foot is momentarily stationary whilst the knee continues to travel forward. This places the calf muscles, Achilles tendon and ligaments and tendons of the foot under stretch. If your ground contact time is relatively quick then this stretch functions very similarly to when you stretch a rubber band. i.e. after stretching a rubber band , if you let it go it flings forward. The stretch placed on the calf and Achilles tendon can propel you forward with no effort required on your behalf.
The effort comes from the stretch in the first place. In running this stretch is given to you by the effect of gravity, the reaction with the ground upon landing and the forwards momentum of the leg. It doesn’t require any additional energy. In fact 50% of the energy absorbed by the foot, ankle and calf can be reused to propel you from the ground. The catch is that this energy is only available for a short period of time. If you delay in releasing the energy, instead of propelling you forward, the energy is dissipated through heat.
This doesn’t just happen in the calf muscles and Achilles tendon, it also happens throughout the whole body to varying degrees. Today we will focus on the lower leg since that is where the biggest gains are to be found.
How can I make use of this free energy?
Keeping ground contact time to a minimum is important, as is training the muscles and tendons to become more efficient at using elastic energy.
Ground contact time is dependent on a number of variables including speed, stride length, stride cadence and the elastic properties of your body. For any given distance we can’t change your speed since you are already running as fast as you can. Stride length, cadence and the elastic properties of your body we can change.
Stride length and Cadence
These two are intrinsically linked. The longer your stride length the slower your cadence for a particular speed and vice versa. The problem with a long stride length occurs if the foot lands forward of your centre of gravity. This will result in a longer ground contact time and a loss of elastic energy to heat. Aiming for a cadence of around 90 per minute (i.e. your right foot should hit the ground approx 90 times per minute) is a good place to start. If you are very tall or short then adjust this figure accordingly.
Elastic Properties of your Body
To train the elastic component we need to perform exercises that have a short ground contact time. A great place to start is a simple 3 dimensional jumping, skipping and hopping routine.
Running is a 3 dimensional activity
Although we run forwards, each of our joints travels through three planes of movement. For example if we look at what happens to the shin bone (tibia) when the foot hits the ground we notice that due to the foot pronating the tibia rotates inwards, travels towards the mid-line of the body and travels forwards over the foot. This 3 dimensional movement occurs in every joint from the foot to the neck. Unless we load the body in three dimensions to replicate the demands of running we will never fully maximize the benefits of our training.
A simple example to illustrate this point is that if you stand on your right leg and hop to the left you are driving the foot into pronation, simulating what happens when you land when you run but with greater intensity. If you then hop back to the right you drive the foot through supination which simulates what happens at push-off. Moving sideways involves a greater pronation and supination force than hopping forward and back. Isn’t the point of a conditioning program to create greater strength than is required in your sport so that when you go back to your sport everything feels easier?
Jump
Start with jumping as this places less strain on the body. Progress slowly and increase the total number of ground contacts by no more than 10% each week.
To perform this routine stand on an imaginary clock face such that you are at the centre.
1. Jump to 12 o’clock and back to the centre
2. Jump to 6 o’clock and back to the centre
3. Jump to 3 o’clock and back to the centre
4. Jump to 9 o’clock and back to the centre
Repeat this but this time land so that your feet point at an angle to the left
Repeat again so that your feet land at an angle to the right
For example you will jump to 12 o’clock but your feet will point 45 degrees or so to the left.
Try and keep the jumps small but with very short ground contact time. Begin with one jump in each direction and progress to 3-5.
Jops
Once you can do this comfortably the next stage is what we call a Jop – its a cross between a jump and a hop. Start on two legs and land on one then hop back to two legs.
Repeat the whole process until you are comfortable doing 3-5 rounds
Hops
Now you are ready for hops. Start of with one hop in each direction and progress to 3-5.
How to progress from hops
In a future blog I will go through how to progress this even further.
Do this routine no more than three times a week, sometimes two will be enough depending on how much other running you are doing. Build up slowly and focus on very short ground contact time. If you start to fatigue and find that your ground contact time is increasing then stop and rest.
Our thanks to Andy for his insights and expertise.
Nice post, interesting…
Just to add a few things to this post.
If you are a heel striker, basically you loose most of the benefits of your tendons elasticity. You cannot preload your achilles, and bounce forward, as you are landing on your heel, so you totally ignore that part of the biomechanics. You can do a lot of hopping and skipping, of course it will help, but if you won’t do the same fore/midfoot stride while running, what you just practiced hopping, you won’t gain the full dollar, just about 30c.
(Even if you land under the boy’s center of gravity, if it is heel first, you cannot pre-load the achilles and the calves, and the hams and the posterior chain…)
Secondly, the 90 approx. stride rate is great, but be cautious with that, it is very hard to change and takes a lot of work. I mean a lot of hard practice. I have been doing drills for almost 7 years now, continuously, and I can tell you, the 90 or above cadence is a super hard thing to achieve.
I would encourage you to do it slowly, adding 2 to your current cadence, and when you ingrained it, add 2 more.
After about a month of cadence practice absence, I went out with my 2.0 Ambit update and did a 90min run with 50min on cadence 90-92. My legs were trashed for 5 days. That is only 3-4 above my average usual cadence, but still your body has to fire more rapidly, access muscle tissues what were dormant before.
A good practice is 30 x 15second super high cadence 3-4 times a week (of course you start with for ie.: 10 x 15sec), you can use higher than usual knee
And one longer run with 2-4 above your current cadence. Start with 10 min, than increase it slowly to 1h. After a couple of months, you will be able to do all your workouts on high cadence, if you keep practicing.
Thanks for your comments, much appreciated and thank-you for taking the time to add to the debate.
dvelente82 – thanks for you comments. A couple of follow up points.
It is still possible to load the tendons elastically if you heel strike. it all depends on where abouts your body is in relation to your feet at the moment of contact. Depending on what study you read somewhere between 70-85% or elite marathoners heel strike and they certainly make use of elastic energy stored in the achilles. I’ll be doing a blog on this soon explaining how.
Cadence wise – 90 is a ball park figure, it will vary according to speed . I agree that changing cadence can be difficult and will load muscles differently and may take a while to adapt to .
I like and agree with your recommendations to increase cadence.
I found that bounding is an exercise which really helps improve this aspect of running form. So many people I train with really struggle doing it first off, but as they improve their ability to bound so their running form becomes lighter and springier, although of course it’s just a general observation of their form, not an in-depth analysis.