‘Why would I run at a higher cadence’? (a detailed look at stride rate)

‘Why would I run at a higher cadence’? (a detailed look at stride rate)

Cadence (definition): the beat, rate, or measure of any rhythmic movement (Dictionary.com)

“Walking and running speeds (metres / second) depend on two characteristics: stride length (m/s) and stride rate (strides/s). Running speeds will increase if stride length remains constant and stride time decreases (stride rate increases) or if stride rate remains constant and stride length increases.” – Neuromechanics of Human Movement

When we first work with runners, a very common question coming back to us is ‘should I actively try to increase my cadence and if so why?’. These are good questions and we can learn something fundamental about how the human body functions by answering them. During the morning filming at our workshops or during the first 10 minutes of a personal consult, we will note down how many strides per minute the runner is taking. Sometimes it’s worthwhile changing it straight away and sometimes it is not. For the coaches reading this I will try to answer the question of ‘when is it worth changing’ in this article as well.

 

Getting a feel for cadence during running

What does it matter anyway? Let us begin by experiencing the difference for ourselves so we can step the discussion down from a theoretical level to a practical and emotional one. If you have a SmartPhone or a computer download a free metronome app and have it play 150 beats per minute. Now, stand up and jump up and down trying to jump once every time you hear a beat. Now increase the metronome beats to 220. Finally, set it to 180 beats per minute and jump up and down.  It is best to do this test barefoot so you get a full sensory picture of what signals travel up through your feet while jumping at the different rhythms. Try to focus on a flat-footed landing – do not jump on your toes (you wouldn’t run on your toes either) – to get the running-specific insight we are looking for. Once you’ve done this write down the difference or keep a mental note in your head of how it felt. If you struggled to feel a difference between 150 and 180 try to do 120 and 170 for now.

 

What you observed

If you are like most people, you will have noticed that the lower rhythms seemed a little bit sluggish. If you do the test persistently (keep jumping for a few minutes), you will notice more stress on the lower leg muscles while doing the lower cadence jumps. In our events, we always see this manifest as people complaining of their calves getting sore. There is a simple physical explanation for this: when the elastic tissues of our body (which includes muscles but primarily concerns fascia and tendons for the purposes of this discussion) are tensioned (lengthened), they store potential energy. Every child is familiar with this effect from the moment they pick up their first elastic – if you pull at both ends, the energy you expend to lengthen to elastic is stored as ‘potential energy’ in the elastic. We can see this as the tension in the elastic. The moment, you let go of one or both ends of the elastic, the potential energy is released and the elastic snaps back to its resting position.

Our human body is designed along an endless web of interconnected elastic bands – the most recognisable being our tendons and the white fascia that envelopes and permeates our muscles and all other tissue. For sake of simplicity, let us use the Achilles tendon as an example here. The Achilles tendon is a so-called ‘passive tissue’ in that it only shortens and lengthens because of other forces acting upon it. So if you contract your calf muscles, the Achilles tendon is shortened. If you move your knee ahead of your toes (which you could do by contracting muscles at the front of your leg or just relaxing and letting the ‘knee drop’ ahead), then the Achilles tendon will be lengthened (and will store energy).

Our free energy – use it or lose it

This ‘potential energy’ stored by our elastic tissues are part of the success story of humankind. Without this source of free energy it would cost an inordinate amount of metabolic energy to move around and do anything. In the example above: if you have to contract the muscles at the front of your leg to lengthen your Achilles tendon, then this muscle contraction will cost energy. When we spend energy to contract muscles there are a few byproducts and one of them is heat. Heat is a problem for athletic performance because the warmer the body get’s the more energy needs to be expended to cool your body temperature back down. Once a critical level of ‘overheating’ is imminent, performance shuts down. Timothy Noakes and other leading researchers in running have long viewed the generation of heat as one of the major constraints of moving running world records down further – one reason smaller runners are now the most likely to excel in the marathon (the more you weigh the more heat you create).

Because we live in a universe that obeys Newton’s Law of the Conservation of Energy (which states that energy can neither be created nor destroyed – only converted from one form to another), the potential energy in your elastic tissues are never ‘lost’ in the real sense – but you can either use it for your benefit or it can turn against you. Let us say you take a stride in running, as your foot makes contact, your Achilles tendon begins to lengthen and tension builds over the tissue storing potential energy. The moment this tension is released as your body passes over your foot and the foot begins to ‘unlock’ from the ground, this potential energy is released. If you are quick enough, you can use this energy to propel you forward – thus adding to your speed (for free). If you are too slow, you lose the effect of this ‘elastic recoil’ and the potential energy is instead converted into heat in your tissues which you then need to spend energy to cool down.

In other words: some stride rates are too slow to take advantage of the elastic recoil of our connective tissues – our elastic body. And it get’s worse: the way you train dictates how elastic you are overall. The more you train slower stride rates and slow and heavy movements, the less elastic you get. The more you train faster stride rates and quick rebound movements, the more elastic you get. This automatically beckons the question: if being elastic is so great why don’t all our bodies naturally select this strategy? There’s no better question than that…

 

Survival, security and stride rate

Our system evolved to select solutions to help survive. If that was not the case, our particular set of genes would have died out long ago. All biological systems share this priority. To put it a bit simplistic: your brain wants to do things that help you survive and this includes two main priorities:

  • Avoid injury
  • Conserve energy

Running at a higher stride rate makes better use of elastic recoil and thus ultimately is a more ‘efficient’ strategy of movement as you acquire a greater proportion of the total energy ‘free of charge’. But this does not mean your brain will automatically select this even when it may have long-term benefits. To understand this, we need to take a short detour and understand how the elasticity of the human body works.

For a long time the common belief was that muscles served as a form of pulley system attached to joints. To picture this old-fashioned view imagine your biceps muscle: when you tense your biceps muscle your elbow joint closes and your lower arm and your hand moves closer to your shoulder and your upper arm. When you tense your triceps, your elbow joint opens and your arm straightens again. In reality, a concerto of muscles are working together at all times as this happens and almost every single muscle in your body is regulating the level of tension it has in response to the simple movement of flexing and unflexing your arm while you sit in your chair reading this. This is the more accurate function of muscles as we understand them today: they set the correct level of tension in your body for whatever movement you are trying to accomplish at any given movement (even if its just sitting still in  chair).*

* The tension you don’t notice in your muscles is called ‘resting’ or ‘residual’ tone (or tension) and is often ignored in analysis of sporting movement because it does not show up on EMG readings which are often used to figure out ‘what muscles do what and when’. The signals for resting tone is communicated in a different way – not through the nervous system which it is outside the scope of this article to describe.

I want you to think of your body as an enormous spider’s web for a moment: imagine if part of the web could contract so that the adjacent strings are being pulled on. Because everything in the spider’s web is connected to everything else, the pull in any one area is felt everywhere. The human body works like this – only at a much more complex three-dimensional level (some now say 4 or 5-dimensional – but let’s not go there today, we just want to talk about cadence!). You can easily test this – simply try and go for a run and tense up your biceps. This should seem fairly irrelevant to running but you will notice pretty quickly that the tension in the arm has a big impact on the mobility of the adjacent shoulder and that the stiffness in the shoulder affects the whole system. To exaggerate this further you can try to tense up lots of muscles and notice how it interferes and/or improves elements of your stride.

 

Test Number 2: Optimal stiffness

Who has not heard runners complain ‘Oh, I’m so stiff’ and then seen them take up a stretching routine, yoga or similar flexibility-oriented practice to address it. It is unfortunate that we have come to associate ‘stiffness’ with something negative (or that we live in a world where it’s hard to have a mature conversation about it!) because it is an absolutely necessary property of an adaptable human system. Stiffness is not always bad and looseness or ‘suppleness’ is not always good.

Before we delve further into this let us again try to ‘feel’ what we are talking about and take a break from theorising: stand up again and repeat the jump test with your metronome set at 180 beats per minute. Try to stiffen up every muscles in your body as much as you possible can – but do so gradually so you can notice what happens as you increase the stiffness. Next, try to do the opposite – as you jump, start with a high level of tension and then let it ‘release’ until you feel as loose as a rag doll.

Again most people will notice that as you increase muscle tension, your body becomes stiffer and more rigid but it also becomes more elastic. This in turn makes your body more ‘reactive’ – meaning that you rebound more easily off the ground and have a better use of the ‘elastic recoil’. But at a certain point the strain of creating all this tension increases your heart rate and at the same time the muscle tension increases the mobility around all joints. This again can be good and bad – in certain situations you do not want too much movement around a joint whereas in other cases you need some. When we move, our system automatically tries to set the ‘optimal tension level’ to accomplish the task safely (without injury) and efficiently (at least possible cost). So when you land on the ground during running, the brain will use whatever information available to set the optimal tension level first of all in the muscles of the lower leg but also in the body as a whole (because no muscle can work in isolation when we move).

 

Your response is only as good as the information you have

The caveat here is ‘information’ – before we even make contact, the brain will use previous experiences to try and adjust to the expected surface. From the very first micro-second after contact first of all through individual cells (a system called the Vibratory Matrix), then a newly discovered system called ‘preflexes’ and then more well-known protective and regulatory systems such as your sense of proprioception (sensory information about the positional relationship of your body’s parts) and your reflexes. All of these systems only work as well as the information they receive and all of these systems can be impaired or misdirected. Imagine for instance if I injected a local anesthetic into your foot so you can no longer feel anything under your feet. You would no longer receive the best possible information and your body would not set the optimal stiffness level to achieve the best elastic recoil.

When the sensory information you receive is tampered with for a long period of time, your body’s automated and habitual responses to certain movements become less than optimal. You can think of these simply as ‘bad movement habits’. Since these movements are habitual, they are picked preferentially even when better options are available. This is because biological organisms are ‘self-organising’ they are not ‘self-optimising’ meaning our body picks movement solutions based on sum of all your life’s experiences but these are not necessarily the best possible. If we were self-optimising, no skill would ever need to be taught – anyone picking up a golf club, for instance, would automatically arrive at the best swing after enough time was spend practicing. This does not happen.

On a more down-to-earth level this means, you should not be worried if increasing your stride rate feels a bit odd or even creates a slightly higher heart rate when you first try to learn to use this new ‘movement strategy’ instead of your older slower cadence. This is natural because this movement is less habitual for your nervous system and your whole system has not been conditioned for it. Whether it is worth making this change then depends on a few considerations.

 

Why change to a higher stride rate and what are the risks?

Anecdotally, it is common knowledge that elite runners take more strides per minute than non-elite runners and that increasing speed also generally increases stride rate – but not in a linear relationship. While there is an obvious benefit in changing – namely that you can learn to use less muscular energy and instead capture more energy from elastic recoil – any change should be run through a ‘cost-benefit analysis’. If you are 75-years-old, uninjured and only intend to run another year before hanging up your boots, then it is probably not worth considering any change. If you are 16-years-old, injury-prone prospective national champion who needs to worry about maximising potential for the long-term, then it may be incredibly worthwhile. Most of us fall in between those two chairs.

The risks of changing to a higher stride rate is firstly the obvious: that you may temporarily become slower and/or need more effort. So you don’t make a change 2 weeks before your big event. Secondly, there’s the risk you will increase your cadence in a manner that is not so efficient. What do we mean by this? Well, everything you do you can do in many different ways. Our body is very good at avoiding really stupid solutions but even with this inbuilt intelligence, some runners try to run 180 steps per minute and end up ruining their efficiency. A good example is ‘road runner syndrome’. Try this simple: run on the spot at a cadence that feels natural to you. Now set the metronome to 180 but put this thought in your mind ‘I’m in a rush, I’m in a rush’ and try this cue “pull foot up, stamp foot down, HURRY, HURRY, HURRY’. A lot of people who make the change on their own end up running like this – creating lots of tension and hurrying their action because they find it stressful to ‘keep up’ with a cadence of 180 bpm. Unsurprisingly heart rate spikes very quickly and running becomes an awful experience.

Three main reasons cause this behaviour: first of all highly strung individuals who over-intellectualise movement (that means – you overthink what you’re doing while you do it). This is a big problem because your conscious brain (the one’s whose thoughts you ‘hear’ in your head) is too slow to manage movement and get’s in the way. You need to think of this as a crazy manager who runs around a team of 200 people trying to manage everything and in the process messes up the organic functioning of the system. Second reason: you have lost your optimal stiffness and thus your elasticity. If you are not very elastic, you cannot get off the ground quickly enough to ‘hit the beat’. But you still want to hit the beat (that’s your intention), so your body finds another strategy – often using more muscles to hurry up the movement. Typical ‘errors’ is actively pushing off into the ground using especially the calf muscles or ‘stamping your foot into the ground’ so you can get it ‘on’ and ‘off’ the ground quicker.

The third problem is that other parts of your technique make it very difficult to run efficiently with a high cadence. Over-striding is the best example – it simply means that you place your landing foot far ahead of your body’s centre of mass. This means you need more time and more muscle action to pull your body past the foot and you will spend longer on the ground as a result. That’s why we always fix posture first – before addressing cadence, rhythm and elasticity. It’s a waste of time trying to improve stride rate if your postural response is not setup properly.

it’s hard to be elastic if you land like this

 

The best way to improve cadence is therefore to setup your postural response correctly which optimises the tension in your tissues and gives you the necessary elasticity to be reactive with the ground. This changes you from a ‘lander’ to a ‘rebounder’.

 

How to train a higher stride rate

In the right order: first you need to fix your posture and your body’s postural response (that means ‘how your body organises its parts in relation to each other based on the challenges it faces’). That’s the topic of another article. Then you can train optimal stiffness and thus elasticity. One method is isometric exercises that mirror the running stride. ‘Isometric’ means exercises where your muscles ‘tense’ without any real shortening or lengthening of the muscle fibres. A good example is if I put an object in your outstretched arms and ask you to hold the object exactly there. I then start pushing away at the object but you try to keep it there. This is an isometric contraction. It used to be thought that isometrics didn’t play a big part in dynamic movements such as running but we have since learnt that the opposite is true. Common wisdom was that the muscles would shorten and lengthen and that tendons and other connective tissue would stay much the same length. This meant that training often focused on strength exercises where the muscles used in running would be lengthened and shortened (for instance a hamstring curl or a calf raise where the hamstring and calf muscles are facing resistance while first contracting – thus shortening – and then lengthening under resistance, what is called an eccentric contraction).

This understanding is depicted graphically on the left in this graphic from Schleip (2015) and Avison (2015) where the muscle fibres are shown in red and the Achilles tendon as the dark zig-zag line. Notice that the muscle fibres are not changing length – the tendon is. What the muscles do instead is contract just enough to create the right level of stiffness in the Achilles tendon to return the best possible amount of energy.

How muscles where believed to work (left). How they actually work (right). Schleip (2015). Avison (2015) adapted from Kawakami (2002)

 

Training shows how this works and it also gives a clue to the dominance of athletes such as the Kenyans. Let’s begin with the popular training form ‘plyometrics’. What you did in the test when jumping at 180 beats per minute was basically plyometrics – very rapid contacts with the ground. Plyometric training uses what is called the ‘stretch-shortening cycle’ to capture the potential energy stored in elastic tissues. There is a very narrow window to do this in: about 150 milliseconds! So you can see why you cannot achieve this with a slow and sluggish cadence.

Plyometric ‘ability’ is very important: in studies done, runner’s plyometric ability accounted for 70% of the correlation with 10 km running performance. This means how elastic you are – naturally – has an enormous effect on explaining how fast you are!

 

Plyometrics and isometrics

Very interestingly, when runners were subjected to plyometric training regimes, they began to use less and less muscle activity rather than more and more. This is not a surprise once you know the content of this article: as you get better at using passive tissues such as tendons to create ‘rebound’ you need to use less muscle activity and thus your muscle activity is lower and your heart rate and heat generation will be lower too improving your running economy – one of the greatest factors influencing performance. When researchers studied the difference between Kenyan and Danish athletes with similar VO2max (maximum oxygen uptake), they noted that the main difference was in running economy. Other researchers noticed that Kenyan athletes had superior development of the connective tissues in the Achilles/calf region. When we train our lower legs in the ‘wrong’ way, we do two things: 1) we achieve too much ‘hypertrophy’ (meaning the muscle get’s bigger) which decreases running economy because the lower leg get’s heavier and 2) we train the muscles to react in an inefficient way. The calf muscles, as an example, may begin to work concentrically (shortening while contracting) and eccentrically (lengthening while contracting) for too long during stance phase (the time on the ground). This is far less energy efficient as this graphic from Frans Bosch brilliant book ‘Strength and Coordination – an integrative approach’ shows:

Green arrow shows the energy cost of producing force with an isometric contraction versus a concentric (Bosch 2015)

 

Since Frans Bosch is one of the leading authorities on running mechanics I will let him explain the take-aways from the above graph directly by quote:

The main difference between the world champion marathon runner and the twentieth-placed runner is efficient technique. …Doing work generates higher metabolic costs than force production in isometric conditions. A technique in which a runner mainly produces force (only possible if enough muscle fibers are recruited) is therefore much more economical than one in which a lot of work has to be done. This influence of increasing energy costs in the transition from mainly producing force to doing more work is far more plausible explanation than the exhaustion of energy supplies for why marathon runners ‘hit the wall’ at he 30-km point. – Bosch, 2015

When muscles become too tired to isometrically contract, we basically begin to use the other two types of contractions more – concentric and eccentric creating much more muscle action and muscle damage and losing our elastic recoil in the process driving up energy demands. To put other words to that here is how the eminent Robert Schleip describes it in his essay ‘Fascial tissues in motion’:

“During rhythmically oscillatory movements, like running or hopping, the muscle fibres contract almost isometrically while the fascial collagenous elements lengthen and shorten like an elastic yo-yo-spring).” – Schleip (2015)

So on the one hand training at a high enough cadence allows you to train this ‘isometric’ strength optimising your muscles for dynamic movements like running and at the same time providing the right kind of stimulus for other connective tissues that help this process (fascia and tendons). On the flipside we have to be careful with exercises that do not work this way as our body may pick up bad habits from that training (this transfer is not guaranteed). If we do a lot of calf raises for instance, we may begin to run with excessive concentric and eccentric contractions AND we may cause hypertrophy in the lower leg reducing our running economy. If we pursue a regimented static stretching program, we may make the stretch reflexes of the lower legs ‘too tolerant’ of being stretched – making our springs too loose and not able to capture as much elastic recoil. There is a reason why lower leg stiffness increases in elite runners and that there stretch reflexes are less tolerant of lengthening of their calf muscles than in untrained runners (basically their ‘elastics’ snap back quicker). If you take a rubber elastic and keep tugging it towards its end range for a few days, you will notice that  it becomes sluggish and stops snapping back as aggressively. Excessive use of isolated static stretching and flexibility routines can cause this type of ‘sluggishness’ making you a less elastic runner. Joanne Avison describes this as ‘bendy Wendy’ syndrome which in layman’s terms means ‘you can be too flexible for running’. Being flexible is not always a good thing and being stiff is not always a bad thing. It’s about degree and the sport-specific demands.

 

Beware passive flexibility and Bendy Wendy!

Static stretching – of whatever kind – needs to be very carefully considered only in scenarios where we are dealing with a level of shortening or tightness over a joint that makes it impossible to do its function. The plethora of research now showing that static stretching before exercise decreases performance (this includes more modern versions such as PNF – even if these can be valuable after exercise) is partly explained by this. Major organisations like FIFA have now restructured their official warm-up (the FIFA 11+) to avoid all static stretching before running and athletics needs to follow suit if we have our athlete’s best interests at heart.

We therefore focus our coaching on making you elastic and reactive rather than focusing on flexibility and strength in isolation none of which can guarantee a positive transfer to running ability. We must avoid thinking that because a particular training method is good for something it is automatically good for everything – two popular examples are Pilates and Yoga. Both have benefits and drawbacks that must be weighed up against the sport-specific requirements you have. If you want to specialise as a runner you cannot simply dive into those two practices (or any other practice) without expecting to get some negative side-effects along with any positives you may get. In reality, our entire fitness industry needs to move away from a ‘system-based’ teaching model (‘I teach Pilates’) to an ‘individual-based’ approach (‘I create more adaptable human beings, this is your starting point and your requirement, and this is what you should do’). The last option cannot be packaged, franchised nor easily learned by coaches – all factors probably explaining why we do not currently have many coaches operating this way.*

* Many ‘old school’ coaches operated this way as there were no fitness systems as such and they had no pressure to monetise or systemise their approach. They simply had an individual, knew what behaviours they wanted and picked whatever methods they knew or could find to generate those behaviours.

 

Conclusion

The key to achieving a higher stride rate in the best way is to create a more elastic body and this requires first of all a proper postural response to be in place and then the right type of isometric and plyometric strength. Plyometrics can be easily trained at low risk by doing low-impact and rapid-contact time jumps on the spot – two-footed or one-footed as well as running with higher cadences once posture is addressed first ideally with the help of a coach. Strength and flexibility training not specific to this type of elastic response – such as static stretching and isolated resistance training utilising shortening and lengthening of muscles against load, should probably be avoided – at least as training for running.

This will also build the correct type of isometric and reactive strength for high performance. Specialised exercises do exist to train this in a way that is likely to transfer into your running stride but are outside the scope of this article. I recommend attending a personal consult or a workshop to learn more – re-read our old articles and keeping an eye out on our website and our YouTube channel.

 

REFERENCES

  • Energy Medicine – The Scientific Basis (2016) James L. Oschmann, PhD
  • Fascia in sport and movement (2015) Robert Schleip
  • In vivo muscle fibre behaviour during counter-movement exercise in humans reveals a significant role for tendon elasticity (2002) Kawakami et al.
  • Neuromechanics of Human Movement (2015) Roger M. Enoka
  • Strength and Coordination – An integrative approach (2015) Frans Bosch
  • Yoga – Fascia, Anatomy and Movement (2015) Joanne Avison

Also published on Medium.

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René

Director and coach at ChampionsEverywhere
The man who had every injury and had to learn how to fix them - Rene Borg is the head coach of Glendalough AC and a passionate runner competing over all distances and terrains.
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