Stretching & Lactic Acid

[kitkat1]

British professor Craig Sharp on Pat Butcher’s blog, talks about “stretching” and “lactic acid”…

"But not long later, I read in one of the good medico-scientific journals a piece of excellent work carried out on over 100 subjects, who had been divided, on a proper physiotherapy assessement of 23 (I think it was) flexibility measures - and were graded as: 1) very flexible; 2) medium, i.e. ‘normal’; 3) poor. And they were then assessed on the treadmill - and their running economy was in inverse relation to their flexibility, just as Harry (Wilson) and John (Anderson) had noted from their own (coaching) experience. The ‘less flexibles’ had. by definition, tighter tendons and ligaments - so had to stretch them more during their stride, which stored more elastic energy in them. The great animal locomotion authority, McNeill Alexander, of whom you’ll know, calculated that over 35% of the energy of a single step was stored (and released) in the Achilles tendon, and around 17% similarly in the ligaments of the longitudical and tranvserse arches of the foot (as it flattened down). This was in humans, running at a speed of about 300m/minute. These data are off the top of my head, but are reasonably accurate…….

At the time of Dave Moorcroft’s great days, he used to come a lot to my lab in Birmingham - about every month at one time. And I was a wee bit worried about just exactly what use I was to him - as his results almost always got steadily better - but I had no real advice other than to keep doing more of the same! So I said to David that I genuinely didn’t see what help I was giving him. And he said “Craig, if I have a bad period in training or racing - and if my lab results are the same as before - then I know that the problem must be in my head - and not my body. But if I’m not going so well, and the results are down a bit - then I know what to deal with. What you give me - is reassurance.”

I remember too, Harry (Wilson) - I think it was - later asked me to do a full lab test at the BOMC on a young elite woman 800m runner, two or three weeks before a major race. I said that there was absolutely no point in doing that, as there wouldn’t be any time to modify anything in the light of the test results. But Harry said “NO, I know that - and the results don’t matter. But it will do her morale good, just to be tested - as all her foreign opponents have been, and she knows that.” So, we tested her, and made quite a fuss of her. And she ran well. So, Harry was using us for psychological reasons, and good for him……

At my age, I am quite interested in ‘the past’ - well especially 1945 - 60. (I was taken by my Polish stepfather to one rainy day of the 1948 Olympics - and saw Gaston Reiff beat Zatopek by 1.5m (0.2s) in the 5000m - having started the final lap with about 50metres of a lead!!! That was what turned me on to Athletics!!! ……

Bengt Saltin…… Dave Costill and Tim Noakes, I would say, are the three best sports physiologists in the world.

…………Another friend, Harvard evolutionary anthropologist Daniel Lieberman…… and others think we shouldn’t wear shoes, Tim Noakes thinks runners drink too much of the wrong drinks - both groups blame the profit motive. And some people are now saying that lactic acid is not the prime cause of fatigue that it has been made out to be - and Tim thinks that fatigue anyway is not locally sited in muscles (lactic acid or glycogen) or lungs or heart or blood (glucose or oxygen) or temperature or dehydration - but in a site in the brain that correlates all of these together - what he calls ‘The Central Fatigue Governor’.

So, some of our old certainties may be going to the wall.’

[speedster12]

@kitkat1

. The ‘less flexibles’ had. by definition, tighter tendons and ligaments - so had to stretch them more during their stride, which stored more elastic energy in them. l.’

So less flexible cound be a benefit?

[Charlie_Francis]

@speedster12

So less flexible cound be a benefit?

I found something similar. Those who were too flexible were more prone to injury and fatigue BUT you need to define what is too flexible and what is not enough at all. Often you would find athletes like Desai Williams who had extremely pliable and loose muscle fibre but also limited ROM compared to others who had big ROM (we’re talking almost splits front to back) but seemingly tight fibre. When you think about it, it makes sense cause Desai had more elastic response and less buildup of fatigue. Often those others had suffered numerous injuries, and, as a result, were advised to stretch like crazy by physios. That equalled less results and more injuries.

[kitkat1]

@Charlie_Francis

I found something similar. Those who were too flexible were more prone to injury and fatigue BUT you need to define what is too flexible and what is not enough at all. Often you would find athletes like Desai Williams who had extremely pliable and loose muscle fibre but also limited ROM compared to others who had big ROM (we’re talking almost splits front to back) but seemingly tight fibre. When you think about it, it makes sense cause Desai had more elastic response and less buildup of fatigue. Often those others had suffered numerous injuries, and, as a result, were advised to stretch like crazy by physios. That equalled less results and more injuries.

The human body remains a mystery still in many ways. It’s interesting, again, that it was coaches who noted the link between “great flexibility” and diminution of performance. Then the scientists went out and confirmed the cause and effect connection. But it is still the people at the cutting edge of performance - great athletes and coaches - who show the way even in defiance sometimes of the science of the day -popularly and erroneously, in my opinion, often referred to as “conventional wisdom” because “wisdom” is begot of experience, the stock in trade of coaches. Or, to put it another way: wisdom is more than information, it is knowledge applied.

[UKcheetah]

How inverse was the reltionship? Were the individuals with ‘poor’ flexibility the most elastic?? That would surprise me as most top athletes seem to display impressive flexibiliy… I would guess in the ‘normal’ range of this experiment??

[Charlie_Francis]

@UKcheetah

How inverse was the reltionship? Were the individuals with ‘poor’ flexibility the most elastic?? That would surprise me as most top athletes seem to display impressive flexibiliy… I would guess in the ‘normal’ range of this experiment??

What is ‘poor’? The fact is, good is what works best overall and tight and too loose simply falls outside those parameters.

[UKcheetah]

@Charlie_Francis

I found something similar. Those who were too flexible were more prone to injury and fatigue BUT you need to define what is too flexible and what is not enough at all. Often you would find athletes like Desai Williams who had extremely pliable and loose muscle fibre but also limited ROM compared to others who had big ROM (we’re talking almost splits front to back) but seemingly tight fibre. When you think about it, it makes sense cause Desai had more elastic response and less buildup of fatigue. Often those others had suffered numerous injuries, and, as a result, were advised to stretch like crazy by physios. That equalled less results and more injuries.

This is interesting. Personally I have a good ROM but very tight fibre. I do fatigue very quickly but I am very elastic… at least at contact times just outside that of sprint foot contacts. I’ve always wondered whether the tighness of fibres indicates anything??