Archive for October, 2010

A brief half-marathon training program

October 30, 2010

This year has been a year in which ill health has again confounded my plans.  After a promising start to the year in which I initially made slow but steady progress in building up both my speed and my leg muscle strength, I ran into the first obstacle with a recurrence of my longstanding arthritis, in January.  The acute inflammation affected several joints; most significantly, my left knee.  It was June before the swelling settled, but even after the acute inflammation settled I have had continuing troubles with spasms of popliteus, patella-femoral syndrome and also ITB syndrome – all probably a consequence of altered knee dynamics due to the pain in the joint.  These problems were compounded by a recurrence of one of my other long-standing problems – metatarsalgia due to congenital downwards protrusion of the second metatarsal head in both feet.  Six weeks of running with heel-strike fixed that problem and now the metatarsalgia is not perceptible while I am running, though I still cannot maintain a stable stationary stance on my left foot.

My health problems were further compounded by evidence of atrial fibrillation.  Despite fairly extensive investigation, the diagnosis is a lingering question, though it is very clear that if I do have AF, it is a rare and transient problem, so for the time being I will simply monitor my heart rate carefully (employing the  R-R mode of my Polar RS800cx, which has proven to be a fairly reliable way of detecting anomalies of heart rate).

By early October, it appeared feasible to resume regular training provided I was careful to avoid exacerbating my knee problems.  However October proved to be a busy month at work.  It has been an interesting month that has included lectures at several conferences in Europe and in China so I have been travelling extensively.  Unfortunately, there has been little opportunity for training and in the four weeks from 1st to 28th October, I managed to average only 16Km of running per week. During the summer, I had been pleased that my aerobic fitness did not appear to have deteriorated too much despite seriously restricted training, but I am afraid that the very sporadic training in October in the absence of a sound fitness base, has resulted in a marked deterioration.

Nonetheless I am eager to get fit enough to run at least one half-marathon this year, even if only to provide a bench-mark against which to measure future improvement.  So I have entered a local race, the Keyworth Turkey Trot, scheduled for 12th December.   If I am to condition my legs adequately for the rigours of racing a half-marathon in six weeks time, I will have to do at least three longish runs in November.   Until today, I had done only three runs of 15Km or more since March.  When I sat down to formulate a plan for a 6 week half-marathon program starting from a base training load of 16 Km per week, it was clear that I would have to bend the usual rule of increasing the length of long runs by no more than 10% at a time. Fortunately my past experience has demonstrated that provided I keep the pace slow, I can increase distance with minimal risk of injury.  As far as I can remember, all injures I have ever sustained have arisen when I have increased intensity rather than distance.

I decided that I would start the 6 week campaign with a longish, easy paced run this morning.    It was yet another lovely late autumn day.  The sun was shining through a thin veil of clouds with enough strength to create perceptible but not uncomfortable warmth.  The yellow-gold of the sycamore leaves and the golden-red of the beech leaves made it a delight to be out-of-doors.    Provisionally I set a target of around 21 Km in the low aerobic zone, though I was prepared to truncate this if my knee showed any sign of discomfort.  As it turned out, the knee was no problem.  However, I had foolishly forgotten to take the scheduled puff of the inhaler I use to control my asthma, after getting up this morning, despite experiencing constriction in my throat on wakening.  After a few minutes of inhaling the cool autumn air, I began to wheeze, and I continued to wheeze for the remainder of the run. My heart rate was somewhat elevated due to the mild breathing difficulty, but the slight reduction in oxygenation was not a serious problem and I was still feeling quite relaxed when I reached 8 Km in around 48 minutes.

Due to a deviation around the site of some tree felling in the woods in Attenborough Reserve I ran a bit further than intended.  At the end, the Polar monitor recorded a distance of 23Km in a time of 2 hours 16 min, though I think my foot-pod needs recalibrating and it is probable the actual distance was only a little over 22Km.  While the pace continued to feel fairly easy throughout, I was aware of increasing tiredness in the later stages.  My average heart rate was 127 bpm, which is about 9 bpm higher than I would expect for a pace around 6 min/Km, but the elevation was probably due to the constriction of my bronchi.  After cooling down, my peak expiratory flow was 280 litre/min compared with a usual value of around 550 litre/min.   Now, a few hours later, my peak flow is back to 500 litre/min, I have some mild stiffness of my muscles and some discomfort in my left knee on standing from a sitting position, but I do not appear to have suffered any serious adverse consequences.

For the next four weeks I will aim to do one long run, one interval session (or long hill session) and an easy run of 8-10Km in the low aerobic zone, together with some trampolining, each week, to increase the resilience of my legs.  In addition, I will do several elliptical cross training sessions to augment my aerobic fitness while minimising stress on my knee.

At the beginning of the year I had anticipated setting a half-marathon target of 99 minutes for this year.  That is clearly out of the question now.  I suspect 110 minutes would be a more reasonable target, but nonetheless, in the spirit of aiming for the stars to increase the likelihood that I at least hit a fairly high tree, I will set a target of 105 minutes.   In fact I will be quite happy if I manage to complete six weeks of systematic training without further health problems.

Note added 31 Oct:

Today I did a relaxed 12.5Km low aerobic run at approximately the same pace as yesterday’s long run.  I compared pace and heart rate over the section 9km to12Km today with the corresponding section from 9 to 12 Km yesterday. Both days this section of the run was on a level path.  Yesterday the mean pace was 5:49 min/Km; aHR was 129  (759 b/Km), and my respiration rate was 45 breaths/min.  Today, average pace was 5:56 min/Km; aHR was 117 (694 b/km) and respiration rate was 30 breaths/min.  The pace was similar though slightly slower today.  Usually beats/Km increases slightly as pace decreases so the decreased beats/Km today demonstrates that my efficiency as assessed by the cardiac work required to maintain a pace in the low aerobic zone, was greatly improved today, though a long way short of the values around 640 b/Km that I was achieving during low aerobic runs at the beginning of the year, prior to my various health problems.  However I think that the substantially lower value of b/km today compared with yesterday reflects the effect of the constriction of my bronchi due to the mild asthma attack that I experienced throughout yesterday’s run.