Scientists: Don't let your coach change your arm swing - "Most people will settle into the swing that is the most efficient

What are the 5k times of the "scientists" quoted in that article? I'd rather listen to the anecdotal evidence from LetsRun male virgins.

p.s. here is a link to the abstract of the actual scientific article.

http://jeb.biologists.org/content/217/14/2456.abstract

Guppy wrote:

It depends. I've seen plenty of kids and girls swing their arms in front of them so that there is more side to side movement than forward-backward movement. This is not efficient. Same idea goes for stride. A lot of kids overstride. When I changed both my footstrike and my stridelength, I became a faster sprinter and came to feel much more comfortable when running fast.

There's no point in focusing a lot on form for most runners, but some runners have awful form that could definitely be improved. It's ignorant to think form should never be adjusted.

This is crap! All sports look at and adjust the biomechanics to be more efficient. It is funny how I always hear these "scientists" say just let it go. Think if all the gymnastics, shot put, figure skating, etc coaches were also that Naive.

I watch the runners I coach for any asymmetrical hitches or inefficiencies in their mechanics. I want them to run as relaxed as possible while maintaining responsiveness. This could be related to their arm swing, and it can also be connected to stride length adaptations for hills, etc. (Also on hills, your arm position changes a bit, elbows go down a bit and the hands up).

I'm not a 'form nut" but in maybe 15% of these athletes, I suggest changes for awkward movement. The runners will try these adjustments out, see if they are comfortable with the adjustments and whether they work, and it invariably helps them improve.

One of the most significant things to look for is the locking up of the inside arm on the turn portion of the track. That's not too uncommon and you would not catch that on a treadmill. Another thing I'll point out is clenched fists, head thrown back, etc.

Anyhow, I disagree with your assertion that arm swing adjustments are not seen as beneficial to some.

3%?!?! GTFO.

What you do with your arms and back affects the posterior kinetic chains that your glutes are part of. That may not mean they need to adhere to some kind of textbook form, but you do need to use them. That's the reason Nijel Amos closes so fast even though it just looks like he's flailing around.

Try this simple demonstration. Stand about 1 1/2 arm lengths in front of a wall and lean forward with your hands flat against it. Push off the wall using only the base of your palms. Then try it again but this time push with your fingers. Are your fingers strong enough to account for the difference? Not in and of themselves, but they're a vital part of a chain of movement that is much weaker if you leave them out.

The most important thing I've heard sprint coaches say is to pull the lead arm down.

marathon man 21 wrote:

Guppy wrote:

It depends. I've seen plenty of kids and girls swing their arms in front of them so that there is more side to side movement than forward-backward movement. This is not efficient. Same idea goes for stride. A lot of kids overstride. When I changed both my footstrike and my stridelength, I became a faster sprinter and came to feel much more comfortable when running fast.

There's no point in focusing a lot on form for most runners, but some runners have awful form that could definitely be improved. It's ignorant to think form should never be adjusted.

This is crap! All sports look at and adjust the biomechanics to be more efficient. It is funny how I always hear these "scientists" say just let it go. Think if all the gymnastics, shot put, figure skating, etc coaches were also that Naive.

Not sure why you gave that response to my post. I said form is important but that there isn't good reason to devote a ton of time to it for most runners (I'm thinking competitive runners here) as most competitive runners have pretty good form already (running a lot at lots of different paces generally produces good form). Only easily identified flaws should be worked on.

I gave the example of myself. I didn't have any major flaws, but I spent a little bit of time working on a few things, and it improved my running ability. Spending a lot more time trying to make my form look a predetermined way (that might not be right for my body and biomechanics) probably would not be an efficient way to spend time.

Overall, it's articles like this that make me so glad I never went in to exercise science/physiology. Even as someone who works mostly in a softer science (biology), a lot of the papers that get published in exercise physiology make me laugh. It's not entirely the fault of the researchers as it can be hard to design meaningful studies in this field, but there're still a lot of funny papers out there. Based on my college experience, I think that's likely do to the field being made up of a bunch of idiot former athletes who couldn't hack it in a real major.

Rodger Kram wrote:

(...) then how much could possibly be gained by small changes ("improvements") to a runner's natural arm swing motion? Probably not much. That's all we are saying with regard to running form.

Measuring precisely the cost is interesting, but I am not sure that makes it easy to guess what `small' changes are going to make. I would never have imagined so big changes between these three positions, for instance.

And for some athletes, half a percent of just about anything matters a lot.

I believe that there are multiple factors that go into this argument.

1- I do believe that there is an optimal form or biomechanic....however, depending on how we are wired or what our genetic makeup is, we may only get 70% of the way there. Is it then an efficient use of our time to focus a lot of energy into training that area? Depends on how much time I suppose.

2- Eventually there comes a point of diminishing returns, where the massive time spent is actually deterring us from other more useful options with our time.

3- I know coaches and runners who feel that "form" is a HUGE part of the performance equation in distance running. ACTUALLY, it isn't. Aerobic capacity, specificity, adaptation to load..... These are all the real keys.

I don't have a problem whatsoever working with an athlete a bit to help them unlearn a bad habit or two, the problem I have is with coaches and in turn their athletes who think too much about form and then use that as a scapegoat for what they are really lacking.

I always have a laugh at joggers who become obsessive about 'form'.

Get a grip.

Thanks for posting and for linking the abstract.

Can you share information on the level of the runners in the study? I haven't seen the full text and the abstract does not mention anything; the NYC article refers to the subjects as "experienced runners". Are we talking about college track athletes? 40 minute 10k masters guys? Old marathoners?

Also, what kind of pace was used for the tests?

Appreciate anything you can share. Thank you.

whatever man wrote:

Anyhow, I disagree with your assertion that arm swing adjustments are not seen as beneficial to some.

He didn't say they were not beneficial. He said they were minimally beneficial.

UK Limey:

Over the years, we've focussed our studies on 3m/sec.

I realize that is slow for competitive runners, but it allows us to be sure that we are accurately measuring all of the energy via oxygen consumption.

The subjects were mostly recreational runners and some competitive.

I don't think we asked but they were your basic 20-22 min 5km types.

Thirteen subjects participated in this study (eight men and five women, age=25.9±3.5 years, mass=67.57±11.73 kg, height=1.77±0.09 m, mean ± s.d.). All subjects wore their own running shoes, were healthy, recreational/competitive runners, had no current injuries and were experienced with treadmill running. As part of our inclusion criteria and to ensure that our experimental protocol required a light to moderate running intensity, we recruited subjects that were comfortable running at an ~08:30 minute/mile pace (3.2 m s−1) for 45 min without rest.

Would the results be different for elite runners? Maybe, but I'd be surprised.

If our question had been "can improvements to form improve running economy?" The following would have been a good experimental design.

But as you can read in the abstract below, there were no improvements in economy following a 6 week treatment in which the runners received feedback about they running form.

I think it would have been great to have measured Mary Cain's running economy before and after she received coaching. But no one did and there is zero objective evidence in support of the idea that form changes improve economy.

Lake MJ, Cavanagh PR

Department of Movement Science and Physical Education, University of Liverpool, United Kingdom.

Medicine and Science in Sports and Exercise [1996, 28(7):860-869]

Running technique and economy (VO2submax) were examined before and after a 6-wk period of running training. Fifteen males were filmed and performed 10-min economy runs at 3.36 m.s-1 on a treadmill. An incremental treadmill test was used to record running performance and maximal oxygen consumption (VO2max). Subjects were randomly assigned to a training group and a control group that did not participate in any running program. There were no significant changes in kinematic variables between pre- and post-training tests for either group. Neither were there any significant physiological changes over the 6 wk in the control group. However, the training group demonstrated a significantly (P < 0.01) increased VO2max (57.7 +/- 6.2 vs 61.3 +/- 6.3 ml.kg-1.min-1) and running performance. VO2submax in the training group was significantly (P < 0.05) worse (41.0 +/- 4.5 vs 42.4 +/- 4.3 ml.kg-1.min-1) post-training, although the percent utilization of VO2max (71.6 +/- 7.9 vs 69.3 +/- 6.9%) and submaximal heart rate (169 +/- 15 vs 161 +/- 15 beats.min-1) were significantly lower (P < 0.05). The training-induced improvements in running performance could be attributed to physiological rather than biomechanical modifications. There were no changes in biomechanical descriptors of running style that signaled changes in running economy.

Rodger

Thanks for the response and I think it's great to see you posting on here.

My thoughts were not so much about if the results would be different for elite runners, but rather if they are different during a race performance. Of course it is entirely the right starting point to begin with steady state effort and prioritise your measurement of energy use and so I'm not at all criticising this bit of work given the question you were trying to answer. The danger I think is that if someone tries to apply your result to a race effort, which is a non-steady state and not a condition covered in the study.

I am speculating but I can't shake the feeling that the difference in energy cost will not remain constant and will snowball under conditions of fatigue. I'm sure you well know what a electromyograph of a muscle working to failure looks like and anyone who has raced knows what it feels like trying to maintain 'form' when closing a race. I'm reminded of some work I first saw referenced in the book "Ironwar" that looked at how muscle recruitment changed during a race effort*. The finding was that the number of muscle recruitment 'options' decreases as the race progresses and the athlete is eventually confined to working with a very specific pattern.

I'm going to stick my neck out and say that a runner who can do a 30 minute 10k on the treadmill will not be able to complete a 30:54 min 10k (103%) with his arms behind his back, even if allowed to train for it.

I'm happy to agree with you that there is not currently any good evidence that shows changes in form improves economy, but also happy to declare myself in the camp that I suspect it can (but certainly not that all such interventions are successful).

Thanks again. Interesting stuff.

*I have loaned that book out so can't look it up at the moment but will gladly do so if you think it is something you are interested in/have not seen.

9 min/mile pace seems too slow to assess the importance of arm carriage, which surely must become a more critical component of efficiency with increasing speed.

I'd like to make one clarification to my earlier statements.

There is no objective evidence that changes to a person's customary running form improve their running economy.

Actually our study is strong support for the idea that changing from horrible form to normal form improves economy.

I suspect that most people on this board would agree that running with the hands clasped behind the lower back constitutes horrible running form. I f I saw some knucklehead running down the Boulder creek path with their hands clasped behind their back, I'd have to say it would be the worst running form I've ever seen.

Compared to running with their hands clasped behind their back, when our subjects ran with normal form, we found that economy improved by 3%. So, yes, form affects economy, but only by a small amount.

If you are coaching someone who has set US high school records and you feel she has horrible form, could changing her form improve her economy and performance by 1%. I could beleive that. And for such a hypothetical person, a 1% improvement would be career changing. But there's no objective proof of that.

If it was possible to recruit 10 subjects who run exactly like Zatopek and 10 who run exactly like Jeptoo, I would that study them in a heartbeat. The hands behind the back form was a way to consistently have people run with horrible form.

The chili analogy is quite funny but not parallel to our study.

I think a better analogy would be to take a group of college students who have a favorite beer. Without the subjects seeing what you are doing, take 2 unmarked glasses of their favorite beer, add a teaspoon of vinegar to one. Tell the subjects that they will now be asked to pick out which is their favorite beer compared to a competitor. Then ask the subjects to choose which glass they prefer. To parallel our results, instead of 50:50 (what you expect by chance), only 53% of the subjects can detect the vinegar and choose the unaltered beer. From that experiment, I would conclude that yes, some people can detect taste but not very many. That is, taste is a minor factor.

Having unfortunately tasted the beer than many University of Colorado students drink (Keystone Light), I suspect these hypothetical vinegar results might not be too far from the truth.

lorainge wrote:

While that may be fine to be efficient in your arm swing for a marathon...

...if you're running an 800m or 1500m you need some power resulting from proper arm swing. That need outweighs "efficiency". I don't think Coach Clark is yelling at his runners that they need to be natural in their arm movements to be "efficient".

Bingo! It is totally different for a marathoner. I changed my arm swing after reading a Lydiard book and it make me much faster at the Marathon. It is definitely more important at long distances. Keep in mind that you don't run with the arms.

With regard to competitive runners, I think that it would be interesting to repeat our study at 6:00 pace in some high caliber runners.

But, there is no evidence that at faster speeds arm swing comprises a larger or smaller % of the total energy required.

If you think that arm swing does comprise a greater %, what do you think comprises a smaller fraction at faster speeds?

Given how slow you seem to be you would have no room to talk. If you're not a jogger, post up those times, old chap!

trollism wrote:

I always have a laugh at joggers who become obsessive about 'form'.

Get a grip.