... ... Heel Strike - all you need to know - Mile27
Sep 012014
 


There is a lot of discussion in the media and running circles about running technique, and specifically heel strike vs forefoot and the pros and cons of each. Unfortunately almost all the discussions have over simplified the topic and miss a few key points.

Before I go into more explanation let me summarise by saying:
1. There is nothing wrong with heel striking depending on where the rest of your body is when your heel strikes the ground.
2. Changing to a fore/mid foot strike doesn’t necessarily improve your running or decrease your risk of injuries and may even increase the risk of injury.
3. Forefoot strike is not necessarily a more effective, more economical way of running. Read on to find out why.

First of all let’s look at what runners actually do in races, not on a treadmill (where the majority of studies are carried out). Depending on which study you read somewhere between 65-85% of elite runners heel strike during a marathon. So if the majority of elite distance runners heel strike why is everybody trying to change to a forefoot strike? As with most things the answers lie in the shades of grey that most discussions on foot strike completely miss.

Speed
The faster you run the more likely you will forefoot strike. Try sprinting for the bus and see if you still heel strike. If we are going to have a discussion on heel vs forefoot strike we need to put that in context of speed. A 400m runner that heel strikes is probably very inefficient, a marathoner who heel strikes may not be. When talking about speed we can’t talk about absolute speed since for a Kenyan marathon runner 3 minute kilometres are comfortable whereas for the average runner it is a sprint.

Heel strike and elastic energy
There is an idea that if you heel strike you can’t take advantage of the elastic energy that can be stored in your Achilles tendon and used to propel you forward. This is based on the notion that it is the little stretch you get between when your forefoot hits the ground and when your heel touches (or moves towards the ground) that loads the Achilles tendon. But even if you heel strike the forward movement of the lower leg relative to the foot will load the Achilles if it happens rapidly enough. If you look at the diagram below you will see in figure 1 that if you heel strike out in front of the knee the lower leg has to move through a large range before it stretches the Achilles. During this time a lot of energy will leak into the ground. If however, like in figure 2, the heel strike is near or underneath your knee the lower leg doesn’t have far to travel before the Achilles becomes loaded.

image

Different types of heel strike
It’s not as black and white as heel strike and forefoot strike. We have midfoot strike and also what I call a glancing heel strike. To understand a glancing heel strike is to understand why elite runners can heel strike and be very efficient and back of the pack runners can heel strike and be very inefficient.

Glancing heel strike
A glancing heel strike has two main distinctions from a normal heel strike:

  • The foot lands close to or under the knee
    The motion of the leg just before contact is either slightly backwards or downwards.
  • This differs to normal heel strike, which occurs when the foot is out in front of the knee and the motion of the leg is forward. Let’s look at both of those in more detail.

    Foot landing position
    If the foot lands out in front of the body then a braking force occurs in the opposite direction of travel. If the foot lands underneath then this minimises any braking force.

    Leg motion
    If the leg is moving forwards at foot contact then once again a braking force occurs. If the leg is moving backwards or downwards at contact then as the foot comes to rest momentarily on the ground the resultant momentum drives the rest of the body forward. Neither of these are dependant on which part of the foot hits the ground – it can happen with either heel or forefoot.

    Effect of shoe on foot strike speed
    The lower the heel on your shoe the more likely you will land mid/forefoot regardless of speed. But barefoot runners can still heel strike. Despite what you read, barefoot or minimalist running isn’t a cure for heel striking but a higher heel will lend itself more to heel strike and the higher the heel the more likely (in general) you are to make contact with the ground out in front of your knee.

    What’s the ideal heel for a shoe?
    That depends on the person, the speed they run at and the distance they run. For a 200m sprint you wont need any heel at all since your heels won’t touch the ground. For an ultramarathon a little bit of support under the heel is probably a good thing as the cumulative load on the calfs and achilles is reduced with a slight heel.
    How much support? I recommend anywhere from 2-8 mm depending on the individual. Go too low and it can overstress your calves and achilles.

    Should you change from heel strike to forefoot strike?
    The focus shouldn’t be on what part of your foot hits the ground but where the rest of your body is when it hits the ground. Minimising braking forces and conserving forwards momentum is the goal as this will improve running economy and decrease your risk of injury. To do this you need to land with foot underneath knee and have the leg travelling backwards or downwards at point of contact. Unfortunately without slow motion video it’s very hard to determine where your body is when your foot hits the ground. A variable that is easier to measure is your stride rate. In general the lower your stride rate the more chance there is of your foot landing out in front of your knee.

    Stride rate
    A quicker stride rate, or cadence, reduces the chance of your foot landing forward of your knee and this is of far more importance than which part of your foot hits the ground first. Changing your stride rate will take time and conscious effort. Be aware it will also load muscles differently so you should make any change gradual. Start by focusing on stride rate during speed sessions (you are doing speed sessions aren’t you?). Particularly notice what happens to your stride length when you fatigue. In many runners fatigue increases stride length making you less effective.

    Is there an ideal stride rate?
    You may have read that 90 is the magic number that we should all be aiming for. This is untrue and stride rate has a number of variables which change from athlete to athlete. Some athletes when they increase their speed increase stride rate, others increase stride distance, others do both. The key point is that if you increase stride length then that length should not come out in front of you, it should come from the distance the leg goes behind your body.

    Hip extension
    One reason why we fatigue as our cadence drops and the foot lands in front is that we may lack hip extension. This means we get more stride length in front of the body rather than behind it. Developing greater dynamic hip extension will help increase stride length without the foot landing forward of the body. If you have plenty of available dynamic hip extension then it may be the glutes and/or hamstrings don’t have sufficient strength to propel you forward far enough to allow a longer stride.

    Should you change your cadence?
    First of all become aware of your cadence and how it changes – if your cadence slows as speed increases or slows when holding the same pace as you tire you can assume you are over-striding. Quicken your stride rate slightly to get your foot back towards your body when it hits the ground. If your cadence is pretty constant at different speeds and less than 90 there may be nothing wrong with that. The only real way to know is to get someone to video you and look at it in slow motion. But it is still worth playing around with cadence to see if a small change feels more economical. Experiment in your speed sessions and see if you feel any better with a slightly higher stride rate. If you do then gradually start to work that into slower speed running. Like any change it should be increased gradually to give the body a chance to adapt. But whether your cadence is 84 or 94 or 104 you need to look at the whole body to determine if that’s a good or bad thing. There is not a magic number that applies to every athlete, our bodies are all individual. So don’t worry if you hit the ground with heel first, there may be nothing wrong with that, despite what you may read in some seemingly scientific articles. Unless you take into consideration the position of the rest of the body when your foot hits the ground it is meaningless.

      14 Responses to “Heel Strike – all you need to know”

    1. A shoe will only make a difference to foot strike for those in the ‘glancing heel strike’ category -the heel won’t get in the way. But a shoe can’t influence how your foot/leg moves in the air prior to landing.

      • Ian – agree to a point that the shoe can’t influence how your foot legs moves in the air prior to landing but it can affect what happens prior to push off which can then affect landing but I don’t think that is the point you are making.

        Interesting question – can a lower heel change someone from forward heel strike to glancing heel strike? I take it you don’t think that is possible? I’m not so sure – changing from a 12mm drop to a 3mm drop ( for example) might just give enough time for the body to come more over the leg. Not saying that a lower heel drop would cause that as a general rule but some individuals that have a minor forward strike and run in a fairly high heel might find a lower heel drop is all it takes.

        • Personally I think a lower heel drop could only affect someone with a glancing heel strike, because those runners, whilst touching down on the heel are not generally loading the heel. A pronounced heel strike meens the runner is reaching out with the lower leg and loading the heel, so even with no heel drop it would make no difference. I’ve seen plenty heel strike in VFF.

          • Agree Iain – all comes down to where the knee is in relation to the foot at initial contact – when your lower leg reaches forward in front of the knee doesnt matter if you heel strike or forefoot strike you have problems . If the foot does strike in front of knee then a higher drop measn you are more likely to heel strike but as you said there are plenty of people heel striking in VFF!

    2. Wonderfully written!

    3. Thanks Andy
      This makes sense of what I have been trying to work out for myself over the past few years. I have recently had an arthroscopy on my right knee for a knackered medial meniscus but see no reason to build back up to ultra running within a few more weeks. I have long thought that a shorter stride length and landing close to under the centre of gravity should make heel striking a more natural, rolling motion. Relying on elastic strain in the achilles just doesn’t cut it over 24 hours or more – nothing is elastic by then.
      I’m unsure exactly what you mean by hip extension though in terms of not increasing stride length forward of the body. As Pauline Hanson would say: please explain.
      Thanks, Mike

      • Hi Mike – thanks for the comments. Agree re building back up to ultras. Just listen to the knee and back off if it complains.
        Re Hip extension and stride length. The length in your stride should be determined from how much length you get after push off rather than how far forward you reach before you land. If you look at elite runners you’ll see how far their trailing leg is behind them whereas if you look at back of the pack you’ll notice the thigh has barely moved behind their body at all. This is dependant on speed to a large extent but even still the runner that has poor hip extension only has one way of increasing stride length and that is to reach further forward as a front leg , rather than the leg going further back when its a trailing leg. Make sense??

        Andy

    4. That’s ‘no reason NOT to build back up to ultras’ of course.

    5. Wise words. Have worked on keeping the landing-foot under hips, and kept more of an eye on cadence (i.e. increased it to ~180 for tempo / race. Haven’t forced it for slower runs though – will get the missus to take some video (something I’ve never done). Staying tall with slight lean from ankles easier said than done when knackered, but does feel better. Will keep more of an eye on cadence moving forwards (with the other usual data).

      Any further thoughts around uphill/downhill (i.e. context is key)?

      I’ve always had tight calves/hamstrings so steered clear of zero-drop – have had issues from lots of hills (ie too much too quick). Are there Hoka-style shoes with 8mm drop or is it less significant with loads of cushion? (Considering Hoka-style if I continue Ultras).

      • Hi Andy – thanks for your comments. Re uphill downhill – it all changes! Topic for another blog I think.

        Re Hoka shoes thing the biggest drop is 6mm so is a big jump from traditional 12mm. Anymore than around 2mm should be eased into to give calves, achilles a chance to adapt

        Andy

    6. interesting article, thanks a lot:)

    7. As a Chi Running Instructor, I’d concur with so much about what you say here. Where your foot lands in relation to your body, and how it is moving when it lands is far more important than heel or forefoot landing. Chi Running advocates midfoot or whole foot landing anyway.

      • Thanks for the comments Jon – I thought Chi was more forefoot so its good to hear your comments re whole foot – I believe there is no best way to run – even the elites differ – finding what works best for the individual is the key

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