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Sept 2002

 

Coach's Column: "Another Piece of the Puzzle" (from Max)

A LITTLE LEARNING IS A DANGEROUS THING, we are told. Primarily because when I was studying the subject at university and I learnt a little about what it does to metals, I have never seen much point in stretching by athletes, except immediately before a race to warm up the relevant muscles without having to run two miles to do it. Until now, that is.

Some metals in some forms have next to no elasticity, others behave more like strong elastic bands. Pull a bar of cast iron in a tensile testing machine and it will stretch in length only 1% or so before breaking apart, but a similar piece of aluminium will extend to half as much again before it busts. Moreover, an aluminium rod stretched by 3% or so will return back unaltered to its original size, shape and strength when removed from the machine. So, I argued, a little stretching of muscles will have no effect and a lottle will merely cause injury. Hence not a good idea. "If in doubt donít do it" is my motto.

ADJUSTMENT OF MUSCLE LENGTH is the heading in the very next paragraph in doctor daughter Sueís "Textbook of Medical Physiology", by Guyton and Hall, after the one on muscle hypertrophy and atrophy which I quoted in CC last time. It says :

"Another type of hypertrophy occurs when muscles are stretched to a greater-than-normal length. This causes new sarcomeres Ė thatís a posh word for new muscle tissue Ė to be added at the ends of the muscle fibres where they attach to the tendons. In fact, new sarcomeres can be added as rapidly as several per minute, illustrating the rapidity of this type of hypertrophy. Conversely, when a muscle remains shortened continually to less than its normal length, sarcomeres at the ends of the muscle fibres disappear approximately as rapidly [my italics]. It is by these processes that muscles are continually remoulded to have the appropriate length for proper muscle contraction."

AT ITS SIMPLEST, racing speed is the product of the number of steps we take in a given time and the length of each one, i.e., if one or the other [or both] of those decline for any reason, then our time to run a race will be slower than it was last time out. Ageing is one such reason, one which may be of particular interest to the majority of VS members because over half of us are more vet set than jet set.

There was a study undertaken in 1989 at the WAVA Championships, held in Eugene, Oregon, and at the US Mastersí National two weeks before in San Diego, CA. A Dr. Nancy Hamilton, Ph.D., videotaped all the heats and finals of all the 100m and 200m races there, i.e. involving over a thousand runners in well over a hundred races. Not surprisingly, it took her a year to analyse them all.

Her comparison of 100m runners in the M35 and M90 age groups interested me. Towards the end of their races the best young runners ran 4.4 steps per second each of length 2.36 metres, whereas the old men could manage only 3.4 steps/second of length 1.42m. That is a reduction of 23% in stepping rate, but a whopping 40% decline in step length. Yes, their taking shorter steps than the youngsters was almost twice as important a reason for the loss of racing speed suffered by the oldies than was their taking fewer steps per second.

FACTORS INFLUENCING STEP LENGTH are primarily a) the power generating capacity of leg and heart muscles working in concert to give an explosive start to each step and b) the proportion of that power which goes to driving us forward and not being wasted overcoming the resistance of the connecting tissues.

Considerations of how better to build up sufficient leg and heart muscle capacity for power production has been the topic of several Coachís and Non-Coachís Columns for the last several editions of VS news, but we have scarcely mentioned the equally important question of how efficient we are in our use of that generated power.

There is a Table in the "Essentials of Exercise Physiology" book I also quoted last time which tells that the energy cost of running a mile is about 100 kilocalories for a 140lb, 10 stone person ; 90kcals for a 9 stone person and so on up and down the scales. But such experiments will have been carried out in some professorís lab and on people who are much more likely to be young students than pensioners. From my own experience of collapsing in ultramarathons through not taking on board sufficient carbohydrate, I guess that moving my aged frame a mile, with its burden of stiff and aged connecting tissues, costs me nearer 120kcals than the 90 it should.

In short, that could be the main reason why I was only an 80+% Age-Graded racer, never a 90+% one, even before I was laid low with osteoarthritis last year.

CONSTRUCTION AND MAINTENANCE. There are two quite separate objectives of training. One is the construction of new soft tissues, i.e., building extra muscle and connecting tissue, up to the level reckoned to be optimum for the seasonís main target race and the other is the maintenance of that hypertrophy, particularly by mending tissue when it is damaged and generally by preventing it from wasting away through atrophy.

My guess is that all training has a maintenance effect, but that there is very little new construction work done after the first six months unless there is a deliberate and effective régime change. Dr Hamilton asked the question what did her research mean for the ageing sprinter. She said :

"While the decline in step length is fairly constant, the greatest changes seem to occur after the age of 50 in the knees and after 60 in the hips. Within the limits of joint and muscle health, the range of motion can be improved with conditioning. In sprinting, the key to hip mobility is to increase the mobility in extension, the kick or drive phase of the stride.

"To do this it is necessary to spend time stretching the quads, the muscles on the front of the thighs. The safest way to stretch these muscles is to warm up for ten to fifteen minutes, then to assume a position where the knee is fully flexed and the hip fully extended. It is much safer if you are not using your body weight to force this stretch.

"Two very good stretch positions are 1) lying on the stomach, bend one knee and then lift that same knee off the ground as high as possible without letting the hip bone come off the ground and 2) use the yoga position called the dancer. From a stand, bend one knee and then reach back to grab that ankle ; pull the leg up as high as possible while bending forward at the hips ; when the chest is parallel to the floor, push the ankle against the hand and continue to lift the leg. Both these stretches are static ones and should be held for 10 seconds on each leg and repeated 3 times.

"No bouncing should be done while stretching because this is when muscle injuries occur. It is safer and more effective to get to a position of maximum stretch and then hold it."

AS IT SO HAPPENS, before I got this November 1990 paper out of the file to help me write this CC, I had stopped training in favour of an attempt, by twice-daily stretching, to rebuild my knee cartilages so that I can run without osteoarthritis-induced pain. The stretch I do is similar in principle to Dr Hamiltonís, but I do it by initially putting one foot on the third step of the stairs and then starting the knee flexing from there. I do ten stretches rather than her three, though, and I hold them at maximum extension for fifteen seconds, not just ten. I intend to start running again in another monthís time.

I had also discussed this problem of declining elasticity with John Keston. He spent many years in the theatre and he told me how even top ballet dancers such as Juliet Prowse would spend hours at the barre descending and then ascending slowly while gracefully doing her pliés. A sort of Long Slow Stretching, one might say, in contrast to my short and sharp 10 minutesí worth, but I donít lay any claim to Orthodoxy these days. Both ideas seem to work, itís just that the one takes six times as long as the other.

John stretches slowly every day, too, as he has done for the past 15 years and mostly by stopping to do so during the less intensive sectors of his daily training outing. Last month he ran a marathon in Bend, Oregon, in a world best time for a 77-year-old [but "only" 93.78% age-graded because the WAVA Standards are much tougher for distance runners over the age of 65 than they are for Open Class athletes]. Whether his 3:19:02 was because of or merely after his stretching-including training we shall never know, but itís unlikely that it was in spite of it. Thereíll be plenty of younger members of the Club who wouldnít fuss over much about the rights and wrongs of the theory behind it if the outcome were that we could run a 3:19 marathon !

The other VS world record holder, Lou Gilchrist Ė she holds the W65 10-mile best of 74:30 Ė is also a regular stretcher. She takes her daily dose of it because she just enjoys being able at her age not just to be able to touch her toes from a standing start and with her knees locked, but to put the palms of her hands on the floor. She ran the Birchwood 10k last month, taking the womenís overall Age-Graded prize with a 90.12% for 46:58. Iím checking with my American contacts if that is a W69 world best.

WHATíS SPECIAL ABOUT STRETCHING that it could have the importance I have just implied? Itís the bit in Guyton & Hall which tells that its effect on muscle build is so sudden and that that benefit "disappears approximately as rapidly". This implies, I believe, that of all the training variables Ė mileage, speed, etc Ė the most important is frequency. Doing something every day, if only stretching, seems to be the key to success.

The stretches which Dr Hamilton describes are static, without any relative movement within the area being stretched and with tension maintained only for 10 seconds. If we obey the "no bouncing" rule, there will be little chance of serious muscle damage being caused. Running, however, is a dynamic activity and we know from bitter experience that over-straining will cause injuries which lead in short order to a DNS.

But thatís not to say that a stretch just below the maximum, static one will have no effect. It is more likely that some stretching occurs every time we bend a knee or take a step. If so, then it follows that the rate of generation of the aforesaid sarcomeres will be least when we bend and step the least and greatest when we do those the most.

To run faster we most need to increase step length, Dr Hamilton says. To do that, we must lift our heels higher, bend our knees more and extend further the striding leg forward before it hits the ground. At the next stride push-off, the straighter the rear leg and the nearer the knees approach the locked position of the race walker, the greater is the forward thrust. In all those actions we are stretching, the least if we walk and the greatest when we run fast.

The implication of all that is that 1) walking very long, 2) running long, not as far as walking but faster and 3) running shorter but faster still are complementary methods of training for racing faster, not mutually exclusive ones. Depending on how much time you have available for the running priority in your life, you can practise any one of these methods Ė or, as John Keston has done this past year, all three concurrently Ė and still do well at the races.

Professional athletes in stable family relationships have no other greater priorities, so they have nothing else to do to pass the time except to run, run and then run some more. And to accept the increased risk of injury by so doing. I soon lost count of the number of athletes who said at the Commonwealth Games that either a) "this is the first time for years I havenít been injured" or b) "I donít know how Iíll go because Iíve been injured". It seems a shame that being continually incapacitated is a hazard which goes with the job.

SUMMARY. My hobby-horses notwithstanding, I suggest you incorporate stretching into your training programme, particularly on those days when you are unable to go running. You never know, one day you too might become a world record holder !

STOP PRESS: In this CC I have noted, yet again, the impossibility of knowing, beyond reasonable doubt, whether our good race results had been achieved because of, in spite of or merely after the training régime we had had faith in on those occasions. The following is a [pathetic] tale of an encounter of mine with the unknown.

As I have related, Iíve been on this Hamilton- and ballet-inspired stretching routine for a month. I had an appointment to see Maureen Ė about a shoulder injury incurred cutting a garden hedge with a weapon which is really too heavy for my meagre upper-body strength Ė and I decided just to jog the 100m down the hill to the traffic lights at the junction of Oakwood Lane with Roundhay Road, just to see if my knees hurt less than they had four weeks previously.

They did seem slightly improved, but when I got to Maureenís I had to report that, much to my surprise, the ball of my right foot was hurting. It didnít take long for her thumbs to find the spot [helped, perhaps, by a reddening around it]. "Youíve a stress fracture", she said, "youíve run on to a stone or landed on the sharp edge of a kerb. Thatíll take six weeks, but you may be able to run a little after only a month". Oh!

My mistake is all too easily explained. I donít run fast any more, my heel and knee lift is so shallow that each step I take is short and my lead foot hits the ground almost from a horizontal direction. When Iím out training, I look down to make sure I steer clear of bumps, potholes, service trench covers, stray stones and kerb edges. But I donít expect to meet such hazards when Iím only jogging.

So Iíve joined the David Beckham/Gary Neville Set, except that their injuries were to their second metatarsals. To keep up with this Jones in future, the fracture has to be to the first one!!