I often get asked – can I run with such and such an injury and can I do anything to lessen the chance of repeating the injury.
After studying many types of running coaching and taking advice from those who have studied elite runners, there is a way to minimise energy waste and minimise impact forces. This enables some to run through injuries and slow motion video can reveal why some injure themselves.
There are 6 principles that we can adopt to help. The idea is to take the ideal model of motion - the wheel – an learn to use its properties when we run.
A wheel is unique because the centre of the wheel always moves exactly parallel to the ground and a small force applied at the centre results in a big movement at the circumference.
In order to recreate those advantages when we run we need to mimic the wheel with our feet
1- Land with the foot behind the knee (bent knee) – to maximise cushioning
2-Land under your Centre Of Gravity – to maximise the angle between impact and support this lessens the force of impact that travels up the leg, minimising braking
3-Lean forward into the run – To lessen push off
4-Minimise vertical oscillation – wasted energy that increases the force of impact and lessens the angle of the direction of impact from the direction of support. This will be achieved through a shorter stride and landing with the foot under our COG.
5- Minimise contact time on the road – lessens push off and vertical oscillation. Lift foot quicker.
(analogy - think of standing beside a wall, for a slight loss of balance a quick light touch with the hand can be sufficient to regain stability, but to push yourself across the room using your arm strength would involve a longer contact and greater forces)
To achieve these there are several tips we can think about when running they are
-Shorten the stride
-Increase the cadence to 90 steps a minute with each foot.
I find the easiest way to do this is focus on the arms as the arms and legs are anatomically linked and they move in sync with the left leg working with the right arm. A cadence of 90 steps with each foot is the same as the arms swinging back and forwards 180 times per minute. So, count left 2 3, right 2 3 and as you say left and right you should notice that your appropriate elbow moves back. It's a Waltz beat for any dancers reading this.
-Make sure the landing foot starts to move backwards before it strikes, so the relative speed difference between the foot and the road is close to zero.
This will be achieved by following some of the other advice about stride length and bent knee. Visualise the action of your leg whilst on a skateboard or scooter.
-Lean from the ankles.
Imagine a runner behind you with an outstretched arm trying to touch your back between your shoulder blades. Your job, should you decide to accept it, is to run so that they can't touch you.
-Let the knees come up in front of you
-Keep the swing leg parallel to the ground so pick the ankle up behind you
-Let the elbows swing behind you – this aligns the upper back and pushes the chest forward so you can lean more and go faster.
-Don’t let the arms swing too far in front of the chest (don’t let them swing more than an inch or two in front
-Pull the ankles up off the ground before your leg straightens behind you
-Pull that ankle up towards the area under your hip so your knee swings forward
-Run as silently as possible and as lightly as possible – run as if sneaking up on someone
-maintain minimal core stabilization as your body rotates forward of your ball of the foot to insure optimal lean
-Relax the legs and arms as much as you can – do not reach fro the ground just let your feet flop
-To go faster – push the elbows back harder – you lean more – let the heels come up higher and the knees come up in front of you and push the hip forward more
Now I realise you cannot think about all this every step of every run. The secret is to focus on one or two and practice it till it becomes second nature. The tips about the arms and leaning often give big rewards very quickly and most start there. Remember We all get daunted when trying to learn to drive or to Ski but very quickly it all becomes second nature and we stop thinking about it.
I am very tired and I am sure I have missed out many aha moments for others – please add to this.
Efficient Running maximise economy and minimise injury
SummaryA summary of the long thread
This article is owned by cabletow
|Feb 2009||Canute||The article contains a lot of good practical advice, but in my opinion has a few misleading statements, some which create risk. I do not wish to change the text, but offer the following comments: ‘Point 5) Minimise contact time on the road – lessens push off and vertical oscillation’. I agree that it is desirable to minimise contact time, but we should be aware of the risks. I do not agree that minimizing contact time lessens vertical oscillation, assuming we are aiming for a constant step rate (such as 90 steps with each foot per min). The shorter the time on the ground, the longer the time in the air if step rate is constant. When in the air we must either be going up (due to push – you cannot lift yourself by your own boot-straps) – or falling. In fact, we fall for about half of the airborne time. The longer we are airborne the further we fall. Thus, for a given step rate, the shorter the time on stance the greater the vertical oscillation when airborne. Furthermore, the push against the ground averaged over the full gait cycle must equal body weight if we are to avoid either slumping to the ground (or taking-off). Therefore at a given cadence, the shorter the time on stance, the greater the push against the ground. If we are on the ground for only a small fraction of each gait cycle, the ground reaction force must be several times body weight, and experiencing such forces more often than once every second over a period of several hours might produce injury such as stress fracture, unless you have built up the required bone strength. ‘Point 2) Land under your Centre Of Gravity’. Landing under or behind the centre of gravity will result in a face-down crash within a few strides, unless the runner is continuously accelerating. A person interested in science can prove this from the law of conservation of angular momentum, but maybe for a practical person, observation of video recordings of elite athletes (and others including Dr R) indicates that they land in front of the centre of gravity when running at constant speed.|
|Nov 2008||BanjoBax||Remove question about advantage 5, replace with an analogy that will hopefull explain, otherwise recommend research POSE/CHI/Stride Mechanics etc web pages for explanation.|
|Aug 2008||Unicorn||Add question about advantage 5|
|Jan 2008||toddytyke||More details on the advice bit - a few of mine and others aha moments.|
|Jan 2008||toddytyke||Added a little detail and removed some of the debateable advice (eg BOF landing)|
|Oct 2007||cabletow||Re done|
|Oct 2007||cabletow||Oh bollox where did it all go!|