Spring and springs

It is less than three weeks to the spring equinox, and the duration of daylight now almost matches the duration of darkness.  Although snowdrops are still the predominant woodland flower, along the river bank the early buttercups are already in bloom.  But most importantly for me, the air temperature is rising.  After a frustrating few months in which the cold dry air has wreaked havoc with my attempts to do interval training, this morning I had only a slight feeling of constriction in the throat.  A few puffs into the peak flow meter revealed that my peak expiratory flow was 555 litres per minute, which is fairly good for a slightly built 63 year old standing 170 cm tall.  So I decided that it was high time for another attempt at 4x1Km intervals in the upper aerobic zone, though in light of recent my experiences I did take a precautionary puff of salbutamol before setting out.


After an easy few Km to warm up, I set out cautiously on the first loop around the 1Km circuit in Clifton Wood, aiming for a pace around 4:30 min/Km.  I had little recent experience to draw on to guide my pace setting, and was pleased to find that I had covered the distance in 4:24 with a mean heart rate of 138.  I was feeling quite comfortable so I increased the pace slightly in each successive interval.  My times for the four intervals were 4:24; 4:19; 4:14: 4:09 and mean heart rate recording were 138; 142; 144; 148.  In the final few hundred metres of the fourth interval I was probably in the anaerobic zone, but nonetheless still fairly comfortable.  My average pace was 4 sec/Km faster than in the only interval session I have managed to do since October, yet the mean heart rate was virtually identical.  It is re-assuring to find that my sessions on the elliptical cross-trainer in the winter months have maintained and perhaps even slightly enhanced my fitness for aerobic running.


After the cool down jog, my peak flow had decreased from 555 litres/min to 430 litres/min, so I had suffered a mild degree of broncho-constriction despite the salbutamol, but I am now reasonably optimistic that the worst of my winter respiratory problems is behind me for another year.


The only untoward event was a fall during the second Km.  I misjudged the height of a tree root protruding about 10 cm above the ground and caught it with my right big toe.  By the time I managed to plant my left foot, my centre of gravity was already too far forward  and I went sprawling face down.  My right knee absorbed most of the impact. I was on my feet and running again within a second or two, with a slight ache in my right knee, and a quite sharp pain radiating from the base of my right big toe.  Yesterdays news headlines regarding Paula Radcliffe’s recent broken toe flashed into my mind, but I decided it was probably only a strain of the metatarsophalangeal joint (at the base of the toe) and kept on running.  I took special care to keep my toes relaxed, in the manner recently recommended by Rick in his comment on my blog, to minimise stress on the toes.  The pain persisted for about 20 minutes but by the end of the cool-down jog, it had subsided to a very mild ache, so it appears that in fact the injury is only a mild strain.


Afterwards, I inspected the site of the fall.  The imprint of my right knee was clearly visible in the moist yet firm earth, but the most dramatic marker was the deep indentation created by my left foot.  It must have slammed into the ground with great force as I attempted to arrest the fall, but because my COG was already too far forward, the ground reaction force only served to create a destabilizing torque.  It was salutary to realize that my right foot must have still been traveling at an appreciable speed relative to the ground at the instant it snagged on the root.  At the stage in the gait cycle when the descending foot is only 10 cm from ground, it should be traveling backwards relative to the torso and at almost zero velocity relative to the ground.  So I probably need to improve the efficiency with which my hamstrings arrest the swinging leg.  On the other hand, the fact that I have only a mild strain of my toe joint rather than a more serious injury does suggest that my hamstrings had not failed too badly in their job.


Spira shoes

The springs that are the other theme this week are the ‘wavesprings’ embedded in the heels and under the forefoot of the Spira running shoes.  I think that there is little doubt that these shoes would reduce stress on the feet and also reduce the eccentric load on quads and calf muscles at footfall, thereby reducing the risk of DOMS and also possibly reducing long term damage to muscles.  Thus I am very tempted to try them, at least for training.


However the big issue is whether or not this is ethical.  One of the reasons why I prefer running to formula one car racing is that running requires little apart from one’s one natural speed, endurance, and mental strength.  Formula one racing no doubt requires greater skill and courage, but technology abolishes equality of opportunity in competition.  However, if we were to demand complete purity in running, we would have to return to the Greek ideal of nude, barefoot competition.  Without even considering the issue of whether or not a nude 63 year old would be a tolerable sight for onlookers, I have no doubt that running shoes are essential for me on account of the mild congenital deformity of my feet.  I need to spread the load that would otherwise be concentrated on the head of my downwards protruding second metatarsal.  Fortunately, despite the current enthusiasm on some quarters for barefoot running, no-one seriously challenges the ethics of using running shoes to protect the feet from injury.


In fact, despite the simplicity of running, we readily accept quite a lot of technology: shoes with spikes; support bras, etc.  Some of these technical items probably enhance performance in addition to minimizing risk of injury.  The question is where we draw the line.  In principle the answer is simple.  A sport is governed by arbitrary rules and participation in competition implies abiding by the rules set by the body governing that competition.


However at this point, we face difficulties with the Spira shoe.  The IAAF rules allow that a running shoe might provide protection for the foot and enhance grip on the ground but must not provide unfair mechanical advantage.  The issue of unfair mechanical advantage is difficult to define.  The US athletics federation rules explicitly specify springs as an example of the type of device that might provide an unfair advantage.  Thus in the US, the rules might be interpreted as implicitly banning the Spira shoe, though until the evidence that the springs in the Spira show give an unfair advantage has been tested in court, it is not absolutely clear that Spira shoes are banned even in the US – though they are explicitly banned by the organizers of the Boston marathon.


One might argue that the IAAF should clarify the issue of whether or not the Spira does provide unfair advantage.  However, I suspect that there is a hidden wisdom in the IAAF’s reluctance to rule on the issue.  Even if the evidence clearly shows that the Spira confers an advantage (which I think is very likely) the word ‘unfair’ is less easily interpreted. 


In swimming, one of the technical advances that produced the greatest improvement in performance within recent decades was the introduction of goggles.  It is probable that goggles improve the ability to judge distance from the end of the pool as the swimmer prepares to turn.  On account of widespread availability and use of swim goggles, there is no clamor to outlaw them.  The recently introduces lazer swim suit has been more controversial, but now a large number of new Olympic records have been set by individuals wearing the suits, it would be scarcely practical to ban the lazer retrospectively.  Even if it were banned, no doubt other manufacturers would introduce suits designed to achieve similar benefits, so the controversy would be endless and might defy any resolution other than a return to nude swimming.


I suspect that explicitly banning the Spira would create a very diversive controversy, as it might be argued that other shoes already in use also provide an advantage.  Spira shoes are already widely available and are not terribly expensive.  If they become widely used within in the next few years we will probably accept them just as we currently allow spikes for track and cross-country events.  If the evidence indicates that they protect muscles from long term damage, I think that the small loss to the purity of our sport would be more than justified.

5 Responses to “Spring and springs”

  1. Andrew(AJH) Says:

    Some nice intervals! I’m glad the fall wasn’t too bad – lucky you were on soft ground and not concrete – but then I guess if you were on concrete there wouldn’t have been a tree route.

    Using the Spira shoes during training, just to reduce the risk of stress related injuries, sounds a good idea to me, but you’re right they might be controversial in competition.

  2. rick Says:

    HI Canute, as you were asking how my legs were feeling the day after me first 13 mile run [inc warm up] in the spira shoes i thought i’d drop you a line or two!
    At the end of my 12 mile tempo run I did feel a bit of tightness in the calf muscles, maybe the shoes make me use these muscles in a different way or it could be the fact i was running in a cold wind wearing shorts!
    Anyway today apart from a general feeling of tiredness my legs had no aches!
    The fact i had no blisters or sore spots is quite impressive and i think they beat my favorite shoes of last year the nike lunar in the comfort stakes .
    I am thinking of testing them on the treadmill against my other shoes, nike explosions and the lunar, maybe running at 10 mph for a set period in each shoe and comparing heart rates!
    My friend says I need to take into account the placebo effect i on yesterdays run, all I know is the shoes gave me the feeling of wanting to run fast, they are lite, absorb shock better than any racing shoe I have worn before and seem to give an extra bounce to the stride!
    Happy to see you got a good session done in the woods, one of the great things about training in the forest are the great scenery and soft ground to run on but always watch out for tree roots or low hanging branches , sooner or laster one of them will get you, as you found out!
    Are you training for any race in particular!
    happy running rick

  3. Ewen Says:

    Good morning Canute. I’m already feeling slightly jealous of your lengthening hours of daylight! You did very well with those intervals – that’s a great endorsement of the elliptical cross-trainer.

    I had a laugh about the tolerable the sight of a nude barefoot runner – especially the thought of one tripping over a tree root. Interesting diagnosis of the trip with your foot still moving forward. If it had been moving “correctly” you still may have stumbled, but not fallen. I shudder to think about the result if you’d fallen on our bone dry trails.

    I’ll be interested in Rick’s evaluation of the Spira shoes. I’d like to see the MythBusters do a “scientific” study that compared the “stride-length” to other shoes. One problem I foresee is that if the wave spring is proven advantageous, then all runners hoping to win races will have to use Spira shoes. Is there another type of spring as good as the wave spring? What if Spira produce a wave spring spike and distance running records were broken by considerable margins? It would be just like the laughable world swimming records we now have with swimmers using the lazer suit.

    Anyway, I would still use Spira shoes in training if they aided recovery. If they are approved by the IAAF I’d use them in races, if not I wouldn’t.

  4. rick Says:

    I think running naked will give you a faster race time due to less air resistance from clothing and lighter weight but you might get arrested for indecent exposure and your private parts might get traumatized from repeated side to side impact!
    but apparently they do have races for nudists if your into that kind of thing!

  5. canute1 Says:

    My main motivation for considering trying the Spira shoes would be to decrease wear and tear on my feet and leg muscles in training. Using them for training but not racing raises the question of whether the transition to racing might be associated with a feeling of heaviness in the legs.
    Rick, if you do the comparison between shoes in the manner you describe, I would e interested to know what the transition feels like.

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