Archive for September, 2008

Stock taking

September 27, 2008

After a long break from running, I took up running again two years ago, and in the past year, have focused on improving my running style to minimise risk of injury and optimise efficiency. As described in previous entries in my blog, I have adopted a style based largely on the recommendations of Gordon Pirie. These recommendations are similar those of Dr Romanov, inventor of the Pose technique.

I have attempted to use my own practical experience, the evidence of video recordings of elite athletes, and the principles of physics and physiology, to weigh up the features of these two schools of thought about efficient running. Largely because video recordings demonstrate that elite athletes land with the point of support ahead of the centre of gravity, as predicted by the principles of physics but contrary to the theory of Pose, I have rejected the Pose recommendation to try to land with point of support beneath the centre of gravity. Nonetheless, I agree with Dr Romanov that it is important to avoid reaching out with the leading foot, and to land with slightly flexed knee and slight plantar flexion of the ankle. I have adopted the style of Pirie slightly modified to include some features of Pose.

At this stage, the crucial questions are: have I avoided injury and have I improved my running performance during the past year.

With regard to avoiding injury, the answer is ‘almost’. Unfortunately I trod heavily on a stone in March, exacerbating my longstanding forefoot problems. That pain still lingers, but since April, it has not limited my running. It is probable that landing on the forefoot increased the impact of the stone, but on the whole, I think the advantages of landing with slight flexion of knee and plantar flexion of the ankle outweigh any possible adverse effects on my forefoot problems. In particular, my highest priority is minimising impact on the knee at foot-strike. Despite having suffered intermittent inflammatory arthritis in my right knee since my teens, I have had only very minor discomfort in my knee during the past year. The arthritis has been less troublesome this year than it was a decade ago. So, with regard to injury, my experiment with running style appears to be a success – though the real proof of the pudding will emerge when I attempt to increase training intensity.

With regard to performance, the answer is ‘no’, but the issue is confounded by the fact that one of my other longstanding minor health problems, asthma, has developed into a more serious problem in the past year and this has significantly limited my training. Although I have covered a reasonable distance in training (an average of 33 miles a week since May) the majority of this training has been low quality because pushing myself anywhere near to lactate threshold has resulted in marked broncho-constriction.

I have only run one race, a half-marathon, which I was persuaded to enter to raise money for charity. My time was 101min 50 sec, which was somewhat disappointing. However, it would be unwise to draw any conclusions from a run for which I was not adequately prepared.

In recent weeks, the asthma has improved substantially, probably due to treatment with inhaled steroids, so today I decided it was time to increase training quality. I set out to do 3x2K intervals at 10K pace. However, at the start I faced a problem: I do not know what my 10K pace is. I have only ever run one 10K race and that was over forty years ago. My recent half-marathon would suggest a current 10K time in the range 45-50 minutes, so I set out with the goal of 9:30 for the first 2K, and intended to adjust pace according to heart rate, aiming for lactate threshold which I expected would be in the vicinity of 140 bpm (88% of HR max). I covered the first 2K in 9:20, with mean heart rate of 137 and felt comfortably below lactate threshold. I increased pace for the second repetition, which I completed in 9:13 with a mean heart rate of 141, and a fairly comfortable ventilation rate. Again I increased pace and completed the third repetition in 8:41 with a mean heart rate of 145, and breathing fairly heavily. I suspect that I was a little above lactate threshold. The overall conclusion is that I probably have the potential for a 45 min 10 K in the near future and during 2K interval sessions, I should aim for a pace of 4:30 per Km.

I jogged home feeling pleased with my performance. As I unlocked the front door, I could hear a faint squeaking like the mewing of a cat locked in the bathroom. As I entered the house I called out ‘where are you, puss?Although our cat interprets human speech according to his own schemas, he usually responds to my utterances whenever he is in a communicative mood. Sure enough, the plaintive mewing continued. It seemed very nearby, but nonetheless followed me through the house. Opening the door to each room failed to reveal a distressed cat. After about 20 seconds the truth dawned. The squeak was from my own lungs. I felt a bit foolish when I realised that in my mild euphoria following a successful training session, I had not registered that I was still somewhat breathless, and the asthma had not gone away. So I will need to proceed with caution as I increase the intensity of training.

The mind of the dancer: Does mind-set influence the benefit of training?

September 20, 2008

In a recent post in mid-July I had mentioned the evidence from brain imaging studies showing that merely imagining an action activates the brain cells that are engaged when performing that action. It follows that merely imaging good running style might establish and strengthen the patterns of brain activity that are required to achieve good running form.

This raises an even more speculative question. What influence does mind-set have on non-voluntary actions such as the activity of the heart and metabolic processes. I do not know of any evidence that imagination alone will make you fit, but maybe the way we think about our training can increase the benefits of training. Alia Crum and Helen Langer of Harvard University carried out a study of the effect of merely informing hotel cleaning staff that their daily cleaning work is good exercise. Four weeks later, their blood pressure and body fat had decreased, even though they did not increase the amount of cleaning they performed. In contrast a comparison group who carried on cleaning as usual without being told that cleaning is good exercise, did not show improvements in fitness. (Crum and Langer, ‘Mind-Set Matters: Exercise and the Placebo Effect’, Psychological Science, 18:165-171;2007). Maybe the practical conclusion is that developing a training plan that makes sense to you increases the benefit of that training compared with performing the same training without knowing why.