Cadence, Heart, Lungs, Nirenstein, Pose and a Humorous but Horrible Video

Rick posted some interesting comments on my recent blog about elliptical cross training.  He pointed out that Haile Gebresalassie averages over 200 steps per minute, whereas I had recommended 180 (i.e. 90 left, 90 right).  Like most of the variables associated with running it is unlikely that there is one magic number that it best for all individuals at all speeds. 

 

A few simple principles of physics demonstrate that for a given pace, there is less up and down motion at higher cadence and probably less risk of injury. When falling under the influence of gravity, the body accelerates continuously. Hence the average speed of fall is greater when the body is airborne longer. The total height of falling is greater during a few long airborne periods than during a larger number of short airborne periods of the same total duration. The mathematics demonstrating this is given in the calculations page in the side bar of my blog.  Similarly the total amount of impact energy that must be absorbed is greater with when the strides are longer at a given speed. The repeated impact with the ground creates risk of repetitive stain injuries in runners, and under the assumption that the risk rises as the force of the impact increases, the risk of injury is almost certainly less with fast short steps that it is with slower cadence and longer strides.

 

However, if you want to maximize efficiency as well as safety the issues are a little more complex. There comes a point where short fast steps become inefficient. I think this point might be reached when length of time on stance becomes too short to allow optimum recovery of energy via elastic recoil of tissues, unless the stiffness of the leg at footfall is increased. The evidence from observing elite athletes suggests that the optimum is probably around 180 steps per second for the majority.  In general sprinters tend to have a slightly greater cadence, possibly because they land with a slightly stiffer leg which recoils more rapidly.  The increased risk of repetitive strain injury is less of a concern when you take about 30 steps in the entire race compared with several hundred thousand steps in a marathon.  However, if you are prepared to run the risk of tendon and joint injuries (especially Achilles tendon injury) then you might run faster marathon if you land with a stiffer leg and higher cadence.

 

At footfall, Haile Gebresalassie takes the weight fairly far forward on his foot, an action that is likely to maximize the storage of elastic energy in his calf muscles.  It may be that one of the several factors that have made him the world marathon record holder is the efficiency with which he recovers impact energy via elastic recoil.  However, I understand that he has required two operations to repair his Achilles tendon.  I personally am cautious about placing too much emphasis on recovery of impact energy via elastic recoil. I therefore aim for a relatively soft landing at a cadence around 180.

 

Rick also points out that by emphasizing loss of leg strength and elasticity as the cause of the decreased stride length that characterizes older runners, I  fail to take account of the decrease in pumping action of the heart and the decrease in efficiency of breathing that also occur with age.  He is absolutely right to emphasize the importance of loss of cardiac and respiratory function.  The reason I focus on leg muscle changes is that I think there maybe more scope for developing better strategies for delaying the loss of leg strength and elasticity.

 

 

With regard to cardiac efficiency, the majority of people suffer a decrease in maximum heart rate as they age.  One factor in this is probably the slow but inexorable decline of the sympathetic nervous system which produces adrenaline.  It is interesting to note that in his recent post ‘Bad, Mad, Glad’, Ewen reported a personal high maximum heart rate recording during the last lap of an exciting race in which he won a silver medal (see link in side bar).  I suspect his adrenaline levels were a bit higher than usual.  However, apart from increasing adrenaline levels, I do not know of anyway of increasing maximum heart rate. The other main cardiac measure is stroke volume. This does appear to respond to training and indeed increasing stroke volume is one of the main goals of aerobic training.  I regard resting heart rate as an indirect measure of stroke volume, and have been pleased that during my recent phase of elliptical training my resting heart rate has fallen from around 53 to around 43, implying that 43 beats is enough to supply the baseline oxygen and nutritional requirements of my body.  Maybe my metabolism has become more efficient, but I suspect a major factor is an increased stroke volume. 

 

The increase in required respiratory effort has also been something I have thought about but on account of my asthma, I have placed my main emphasis on minimizing the irritation of my bronchi and bronchioles.  However, I have noticed that even when I am not wheezing my respiratory effort in the upper aerobic zone is greater on the elliptical than when running.  I do not know why, but speculate that due relatively greater use of fast twitch fibres I am generating more lactic acid and therefore increasing blood acidity which might be expected to provide a greater drive to respiration.  Blowing off more carbon dioxide will decrease blood acidity and compensate for the increase in lactic acid.  If this is the case, then an added advantage of the elliptical is that I will be working my respiratory muscles harder and potentially minimizing the loss of respiratory muscle strength as I grow older. 

 

Finally Rick points out that he has been greatly helped by adopting Jack Nirenstein’s running technique.  Jack Nirenstein advocates a technique that has some similarity to the Pose technique advocated by Nicholas Romanov. The cardinal theoretical principle is the use of gravity to promote a fall forwards.  Perhaps the most interesting puzzle that I have conjured with in my recent attempts to understand running technique is the claim that gravity can provide net forward propulsion.  There are people who undoubtedly find that the Pose technique or the Nirenstein technique are helpful, but it simple consideration of the laws of physics suggests that the theoretical basis of these techniques cannot be correct. 

 

It is true that when the centre of mass of the body is in front of the point of support during stance, that gravity will exert a torque that causes an increase in rotaion in a head forwards and downwards direction.  This is very beneficial when accelerating and indeed it well illustrated by the exaggerated forward lean of a sprinter propelling him or herself from the blocks.  However, unless this head forwards and downwards rotation is counteracted by a forceful application of torque directed in the opposite direction, the runner will inevitable suffer a face down crash within a few strides.. This is an inevitable consequence of the law of conservation of angular momentum. 

 

The Pose coach, Cabletow, whom I regard as the person with the best intuitive grasp of running mechanics that I have ever met (I would venture to speculate that he has a more sound intuitive grasp that Nicholas Romanov himself), recently commented on the Fetch efficient running thread that my application of the principles of physics applies only to stick men.  Unfortunately that is not so.  One or two of the approximate models that I have proposed for the purpose of calculations are indeed approximations that apply to stick men, but the basic conservation laws of physics such as the law of conservation of energy and the laws of conservation of both linear and angular momentum apply to flexible human beings as much as to rigid sticks.. 

 

Some time ago there was a humorous but horrible illustration of the law of conservation of angular momentum in one of those humorous but horrible television programs that show home videos of domestic accidents and other forms of everyday mayhem.  The video clip (which was also published on You Tube but I am afraid I do not have the link) showed a man descending down a slide holding an infant in his arms.  At the bottom of the slide, the man landed on his feet and stepped forwards as he began to rotate to the upright position.  However, because the combined centre of gravity of the man-infant combination was so far forward, he could not get his foot forward quickly enough to plant it in front of his centre of gravity at footfall.  With each step, the man-infant combo accumulated angular momentum-in a head forward and downward direction (unfortunately also an infant forward and downward direction).  They continued to accelerate forwards but also to rotate out of control.  After about 11 steps they suffered the inevitable face-down crash.  The video clip did no make it clear whether or not the infant was hurt, but I hope not.

 

The forward lean proposed by Pose and by Nirenstein is good for acceleration but must be counteracted by a force that exerts an opposing torque at some point in the gait cycle if a face down crash is to be avoided.  Thus, as far as I can see the theoretical basis of both Pose and the Nirenstein methods is fundamentally flawed.  As I have stated here on my blog before, I believe that the Pose method has some very good features.  I am prepared to accept the same of the Nirenstein method, though I have not attempted to practice it.  In particular by taking the focus away from a powerful push off and claiming that gravity provides net forward propulsion, these two methods maximize relaxation while running and minimize the risk of dangerous over-striding.  However, if the goal is to maximize speed without compromising safety, I think one of the goals is to work out how best to develop and apply a powerful push off without over-striding.   I suspect that a major part of the answer is a well timed deployment of hamstrings and other hip extensors in mid-airborne phase to arrest the forward trajectory of the leg relative to the trunk

 

So I am grateful to Rick for his interesting comments.  For me they illustrate the issues that have been at the heart of a lot of my ponderings in the past year or so.

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21 Responses to “Cadence, Heart, Lungs, Nirenstein, Pose and a Humorous but Horrible Video”

  1. rick Says:

    HI AGAIN,
    jack nirenstein, does not not recommend leaning forward as you say and his technique does not have any similarity with pose or any other gravity running Technique, I suggest you read his book ‘ just undo it’ avialable as a ebook for only a few pounds.
    IF YOU REALLY THINK YOU CAN PUSH YOURSELF ALONG WITH YOUR HAMSTRINGS GLUTS TRY THIS, stand on one leg now using the muscles of the grounded leg push yourself forward, do you move!
    STAND TWO FEET AWAY FROM A WALL, NOW LEAN AGAINST THE WALL, FEEL GRAVITY PUSHING YOUR BODY INTO THE WALL, NOW EXERT MAXIMUM LEG MUSCLE FORCE, USING YOUR HAMS AND GLUTS, CAN YOU FEEL YOUR BODY PRESSING INTO THE WALL MORE!
    The truth is we can only move forward with gravity and momentum , the grounded leg can not push forward because the quads are working concentrically to hold you up, the hamstrings can not work at the same time.
    most coaches tell us to push forward to run faster, but all you can do is tense up the muscles in the back of your legs , leading to hamstring pulls calf tears and lower back problems, but we have been taught to run this way for so long that it becomes difficult to accept the truth!
    If gravity did not help us run faster why does man run slow on the moon!
    We all run with gravity, we all use gravity to run faster!
    Leaning forward from the ankles only helps you run faster for the first couple of steps, Jack can show you how to use gravity to run faster,
    the great news is his method is easy to lean, easy on your body and the first time you run out the door you can see improvement, no expensive pose teacher or 2 hours of running drills needed!
    READ HIS BOOK, GIVE IT A GO!

  2. rick Says:

    DECREASE IN MAX HEART RATE
    Great topic
    at age 29 [ when i was cycle racing] my max was 183bpm, now I can reach only 160 at 47 years old, yet last year after 15 years running i equaled my best 1 mile interval times, does the heart not get bigger and stronger with more endurance training and therefore pump more blood per beat than before needing less bpm to do its job.
    Adrenaline, if you keep doing the same races year after year one can become bored, to keep the adrenaline flowing try different races, ie trail, or hill races, different distances, etc.

  3. canute1 Says:

    Dear Rick
    Thanks for your comments. I am sorry if it appeared that I was implying that Jack Nirenstein advocates forward lean of the torso. What he states is ‘All objects, animal or inanimate, that stand off balance will have the top of the object fall ahead of the base’. As far as I understand him, the unbalancing that he proposes occurs when the centre of gravity is ahead of the grounded foot in the late part of the stance phase. This can be achieved with the torso perfectly upright, provided the hip is extended.
    Nirenstein does imply that gravity provides forward propulsion. He states: ‘Legs will walk, run, sprint, only by falling’, and in this respect the theory underpinning his technique is similar to Pose. I consider that the claim that legs run ‘only by falling’ is true in a very restricted sense, but it is misleading, as there is a part of the gait cycle in which the leg rises. More importantly, any forward and downwards directed angular momentum provided by gravity must be balanced by backward and upward angular momentum imparted at some other stage in the gait cycle if a face down crash is to be avoided. In practice most of this is imparted by gravity acting when the centre of mass is behind the point of support in early stance phase. (Headwind might also contribute). However, I accept that the belief that gravity provides net forwards propulsion allows some people to achieve a relaxed style of running which can be beneficial.

    You point out the importance of momentum. I agree completely with the importance of momentum. On a level surface, in the absence of wind resistance, momentum is all that is needed to maintain a constant horizontal velocity. That is Newton’s first law of motion. However if we are to land with a leg in position to support the body at the end of each airborne phase, we need to employ muscle power to get the body airborne, to swing the trailing leg forwards and to arrest the swing. It is for these tasks that muscular strength is required while running at constant velocity.

    We are in complete agreement about the possibility of increasing cardiac output via aerobic training. Furthermore, it is probable that maximum heart rate is not as important as stroke volume for achieving the task of delivering oxygen and nutrients to the muscles. However, I suspect that the decrease in maximum heart rate that many people experience as they age does contribute to the decrease in peak cardiac output with age. Nonetheless, I am very impressed by the performances you achieve at age 47 with a maximum heart rate of 160. I suspect that your stroke volume is large and also that you have well developed capillaries and mitochondria in your muscles. I wonder how much of that is a legacy of your cycling days.

  4. rick Says:

    CADENCE ‘ YOU COULD WRITE A BOOK ON THIS’
    I think you will find most new runners or cyclists start out at 120- 140 revolutions per min, increasing to higher levels as they get fitter!
    With special training its possible to train your ‘motor skills’ so you can handle a much faster turnover!
    Back when i started cycle time trial racing in the mid 80’s most of the American cycling and tri books recommended 85-90 revs per min [ based on ‘ scientific research’] , where as the European coaches were recommending far high rpm 95+
    I used the 85-90 range for some time until I started road racing as well, you have to be able to peddle really fast in a road race to deal with the constant changing pace, after a while my nervous system got used to the higher leg turnover and i found that in time trials my natural cadence increased to 90-95 rpm, i found my times improve and i noticed that riding into a headwind was a whole lot easer peddling a smaller gear faster.
    Lance Armstrongs coach Chris Carmicheal did a whole load of research, into cadence and efficiency
    the end result was he got lance out of his big gear pushing ways and into rapid peddling 100+ rpm, and the rest is history!
    True running and cycling are not the same butthere are some lessons to learned hear and one is the lab tests that sports scientists do often only lead to the results the scientist is looking for.
    for example, if an athlete always trains at say 90 rpm then is asked to increase to 100+ it will take time for his nervous system to adapt ! but the scientist will not take this into account only using the results on the day! if the athlete was tested again after a month or two after training at higher revs he might well be more efficient!

    I myself have set off way to fast in races so that i could run with the top runners [ for at least 1/2 mile by which time i was blowing up and had tp slow]and watch and mimic there styles, first thing you will notice is there legs are turning over very fast, the further down the field the slower the runners rpm are until the last runners come past looking almost in slow motion!
    The great news is even a aging runner can improve his turnover and the best way is through using jack nirenstein’s methods!

    If a longer stride was the answer to running faster than try this;
    use the bounding drill and see how fast you can run !
    ANSWER; NOT VERY FAST!
    HAPPY FAST AND INJURY FREE RUNNING, RICK

  5. rick Says:

    hi again,
    THANKS FOR REPLY.
    JACK NIRENSTEIN does indeed put a great deal of importants into muscle strength unlike chi running etc, i don’t think he is saying gravity is doing all the work in fact he says it takes a lot of muscular work to bring the feet forwards and back.
    If you have ever tripped on a paving stone or tree root you will have experienced the sudden pull of gravity as your foot stays behind and your body moves forward, Jacks method uses gravity by landing further back than normal, putting you in a falling position, the faster you want to run the more behind you land, the slower you want to run the more infront you land. the faster your stride the more times you put yourself in a position of imbalance and experience the pull of gravity.
    AT THE END OF THE DAY THE IMPORTANT THINK IS IT WORKS!
    NOT ONLY ON THE FLAT BUT INTO HEADWINDS OR UP HILLS, I AM SEEING AN INCREASE IN SPEED, I am now running my tempo runs faster than in the summer, yet i am running in freezing conditions and wearing heavy thermal cycle jacket and track suite bottoms and am yet some way off my summer fitness, my improvement when i can run in warmer conditions and in vest and shorts will be very interesting!

  6. canute1 Says:

    Rick, Thanks. I agree that an aging runner can increase cadence. For the time being I am happy to stay around 180 (90 left; 90 right), as my efficiency appears to decrease above that rate. However, I agree that Lance Armstrong’s success provides reason to believe that cadences above 100 rpm work well on the bicycle. Lance has built a tremendous physique. Do you know whether or not the majotiy of road racing cyclists now aim for cadence above 100? I would not rule out trying a further increase in my running cadence, but Gebresalassie’s achilles problems make me cautious about seeking to emulate him. There might also be some other differences between him and myself that I should also take into account.

  7. rick Says:

    p.s.
    i should point out i have been using the nirenstein method since December,before that i trained using 1 st pose then chi and finally evolution running, each method seemed to bring about different injury problems, and as i said before jack was the only one who could explain to me why i was getting injured!

  8. rick Says:

    IF YOU WATCH THE TOUR DE FRANCE YOU CAN SEE A BIG VARIATION IN LEG TURNOVER, BERNARD HENAULT UNDER THE COACHING OF CYRILLE GUIMARD WAS ONE OF THE FIRST TO USE REALLY BIG GEARS.
    i think he had quite a few tendon and knee ligament problems
    in the late 80’s and 90’s the top coaches were recommending power training in very big gears sitting in the saddle up steep hills at under 60 revs. I’M NOT REALLY IN TOUCH WITH CYCLING NOW so not really sure if riders are following lances high revs method!
    As for mr Gebresalassie you will notice he runs very much on the balls of his feet, great for return of energy but very hard on your calf muscles.
    I tore my calf muscles 3 x following the pose ball of the foot running!
    I think a midfoot strike is best for the distance runner and for us older guys it cuts out alot of injury even if you lose a little speed doing it!

  9. rick Says:

    I think that mr Gebresalassie’s injury is the resukt of ball of the foot running not high leg turnover which would result in less stress and impact and hence less injury!
    NICE ‘TALKING’ TO YOU CANUTE, its refreshing talking to you!

  10. canute1 Says:

    Rick, You are probably right about the ball of the foot landing being the main cause of Gebresalassie’s achilles problems. One of my most serious misgivings of Pose is that Nicholas Romanov has not openly acknowdged the potential dangers of landing on the ball of the foot. At least some good Pose coaches do acknowledge this danger in private but I suspect that people are still at risk of achilles and calf injuries due to the fact that the illustrations in the Pose book still show an exaggerated fore-foot landing.

    I am certainly very impressed by the fact that you are running so well using the Nirenstein technique.

  11. Ewen Says:

    Is there not some ‘pushing off the ground’ by runners who use the Pose or Nirenstein technique? I’d have thought that when the foot lands, it has ‘stored energy’ which is released against the ground (more energy when running faster or with a ‘stiffer’ stride), even if the runner is not trying to actively ‘push’ off the ground.

    My experience with maximum HR is that mine has declined over the years – 20 years ago I used to race at 170/min, now it’s 155. I know I’ve also suffered a loss of muscle strength or elasticity as I used to high jump 1.55 metres and the last time I tried it was 1.35 metres.

    With technique, it’s interesting to compare my performances over 1500 metres when using my normal running technique and race-walking. With both, I have a similar cadence (for this example, say 180/min). If I take 8 minutes to walk 1500m, that’s 1440 strides of 1.04 metres. My stride is understandably short as contact with the ground has to be maintained and the knee straightened under the body – not a very efficient means of locomotion. Also, there’s not the same elastic recoil with walking when compared to running. To walk at this speed, my HR is very similar to when running 1500m (say around an average of 153).

    If I run 1500m in 5:40 at 180/min cadence, that’s only 1020 strides of 1.47 metres in length – so am I faster because running is more efficient than walking? If I wanted to run 5:00 for 1500m (I think impossible now, although once it was ‘jogging’), at 180/min cadence, there would be 900 strides of 1.67 metres in length. So, I’ve lost 20cm per stride for a 1500m race in the last 10 years.

    As a generalisation, I’d say shorter people have an easier time running with a higher cadence than 180. Not sure why, but that’s just my observation of runners with different leg-lengths.

  12. rick Says:

    The first time I saw a Nirenstein video on youtube, I thought I,ll give that a miss! but some months later for some reason I went back and followed it up.
    Nirenstein is now 80 years old and maybe at first he may come across as a bit of an eccentric! but sifting through his book and videos his ideas seemed to make a lot of sense !
    Anyway I guess different methods suite different people and for me at least I am more than happy with the results!

    Here is a useful tip I learned from ‘NEXT LEVEL FITNESS AND ATHLETICS’ when You land midfoot or forefoot keep your toes up and not pressing down into the sole of the shoe.
    WHY! because if your toes are pressing down it makes your arch rigid , raising the toes relaxes the arch and lets it work as a natural spring and shock absorber, TRY IT YOU WILL BE AMAZED BY THE DIFFERENCE!

  13. rick Says:

    AGE AND PERFORMANCE
    I have a friend called Steve James he has been a world champion in his age group and held the world 60 age group world record for 5 k, I had the privilege of training with him for over ten years and has been an inspiration to me to keep running! steve ran 4.04 for the mile as a teenager, ran 2.27 for the marathon at 45 years old and told me he had his best year on the road at 49! now at over 70 he is still running strong if a little slower!
    AGE CAN BE A BARRIER IF YOU WANT IT TO BE! BUT I THINK THE BEST WAY TO DEAL WITH BEING A MASTERS RUNNER IS TREAT EACH NEW YEAR AS A NEW START AND A NEW CHALLENGE!

  14. Averagebum Says:

    Hi Rick, I have both the book (in fact I bought 2 e-copies of it thinking the different titles were for 2 different books), and have watched the Youtube videos of Jack Nirenstein’s method of running. The problem is I really can’t understand any of it. Firstly, how can we control how far our foot lands behind our center of gravity? And secondly, what did he mean by raising the front of our feet to fall forward? I and one of my students tried doing this and just couldn’t help falling backward! Thirdly, when we start running or need to accelerate, how can we put our foot behind us to start falling forward? Please pardon my stupidity, Rick!

  15. Averagebum Says:

    Bu the way, Canute, your comments on technique have helped me alot, to regain my former technique before my non-running related injury that has side-lined me for more than 8 years. Thanks very very much!

  16. Averagebum Says:

    I’m sorry Rick, in fact it wasn’t the lifting of the fore foot that confused me. It was the pressing the toes into the ground part. I and my student couldn’t stop ourselves from falling forward when we did that, even though Jack claimed that we shouldn’t be able to move forward while pressing our toes on the ground.

  17. NOBIV Says:

    Folks, I am a little late to this discussion. The differences between the two methods brought me here. Having said that I noticed the statement about the toes point up to relax the arch in a forefoot or mid foot strike. Now I might be missing something here, but I just removed my shoe and felt my arch in both positions. My arch is definitly tighter when my toes are pointed up and relaxed when my toes are pointing down – that’s the exact opposite of what was said. Perhaps I am taking it out of context.

    Additionally, I have used the heel-toe, mid-foot shuffle, high cadence for quite some time. And althought it is less stressful on my calf, it is slow very very slow. Having said that, I am starting to use more of a forefoot strike and yes I do have some tendernous in my calf.

    However, setting aside all of the gravity stuff. It would appear to this lay person that placing less of your foot on the ground while increasing turnover will provide the fastest mode of running. Am I missing something? Likewise and naturally, turnover is directly related to stride length simply stated it is easier to turnover a shorter stride than a longer one – no different on the bike.

  18. canute1 Says:

    Nobiv, Thanks for your comments. Regarding your comment on Rick’s comment about toe up or toes down, I agree that the tension in the longitudinal arch will be greater with toes up. I think that greater tension in the arch will promote greater elastic recoil and therefore promote increased speed, and might be worthwhile for sprinters. However, I suspect that for distance runners the risk of planatar fasciitis might be greater. The same applies to keeping the heel off the ground. For sprinters, forefoot landing with heel kept off the ground is almost certainly best, but for distance runners the risk of calf injury is high (as demonstrated by Ross Tucker’s report of the injuries following the Arendse Pose v midfoot v heel-strike trial. http://www.sportsscientists.com/2007/09/running-technique-part-ii-scientific.html
    For many distance runners the thing that causes the most serious slowing is injury. That is why I advocate relaxing the ankle to allow the heel to touch ground in mid-stance.

  19. Averagebum Says:

    Greater dorsiflexion of the foot produces plantar fascitis???

    In fact, from all my knowledge and coaching experience it is plantar flexion and landing on the balls of the feet with the ankles fixed, that causes plantar fascitis, ie, we land hard on the balls of the feet without give.

  20. canute1 Says:

    I agree that plantar flexion of the ankle and landing on the balls of the feet ‘without give’ create risk of PF. I also suspect that dorsiflexion of the toes while landing on the ball of the foot with ankle plantar flexed is likely to produce an even greater risk of PF because the dorsiflexion of the toes is likley to result in even greater tension in the plantar fascia, as described by NOBIV above.

  21. Averagebum Says:

    Canute, I understand what you mean now.

    Actually I suspected what you meant but because the general population normally mean ankle dorsiflexion when they say toes up, I thought that was what you meant.

    Thanks for clarifying and have a great week!

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