TRAINING: Week by Week Comparison

My second week back is almost completed. All that's left is a 41min hill run tomorrow and a 46min marathon pace run on Sunday. So in other words, the majority of the slower mileage has crowded together during my weekend.

Today I completed my second structured fartlek session, focusing solely on speed (not on VO2 max or fatigue resistance) and therefore being structured as 30sec sprints with a long 1:30 float in between to allow for full recovery (or almost full!).

This week and last I performed 8 repetitions, and there's a favourable improvement already. My average speed has moved from 03:49 (15.7kph) to 3:27 (17.2kph) and my best sprints from 3:15 (18.5kph) to 3:03 (19.7kph).

Total Recall
While I'm delighted with this improvement it's not that outrageous an improvement. When I had to stop through injury I was a TPL 26 and should have been doing sessions like this at 03:23 (17.7kph) average speed. Today's session was equivalent of a 27, meaning my body has just very quickly reestablished the neural connections to my muscles.

So its important not to take this as a sign that I'm already ready to go back and train at 27 level (indeed I ran my base run today at a TPL 28 level, but I did feel frisky). The short intervals remind the body of its full former speed potential, something that is easily held over a 30 second distance.

Sources of Speed Loss
The major losses of fitness I have sustained over the last 3 months are unlikely to be much related to maximum speed (as this attribute is to a high degree genetic). Instead, its more likely that my aerobic base has eroded, decreasing my fatigue resistance and maximum sustainable pace (at any speed).

Therefore ny attempt to train yet at TPL 27 level will no doubt meet with disappointment. My brain remembers how to use the neural pathways enabling it to recruit enough motor units to attain a given speed. It may not anymore have the engine and fuel system to sustain this without having to activate its safety mechanism to protect the heart, however.

At the end of the day, the practice of running is to practice communication between your brain and your muscles (Fitzgerald 2008). So anyone returning from injury should heed this warning: Do no take early performances in short speed intervals for safe signs of improved Target Pace Level. The brain's ability to recollect learned patterns is infinite, thus anything learned can never be truly unlearned (damage to brain tissue can in fact break your connection to parts of your knowledge, but as modern physics is now hypothesizing, the information itself will remain as long as the universe remains).

This interesting physical anecdote means that your brain will never forget the training you have done which explains the well-observed fact that previously well-trained runners regain fitness quicker than untrained individuals. We still have much to learn about the specifics of this observation, but the key seems to be that although this observation is true, the support systems (capillaries, bone density, mitochondria, muscle fibres) needed to work at your "old" speed may no longer be fully intact and must be allowed time to rebuild.

So in conclusion, things are progressing well, and its interesting to see how the Brain Training paradigm effectively explains the actual developments I can observe in my own running.