10 x 400m was on the cards last night at the track. Pat Murphy, my Thursday evening partner now for three weeks, was recovering from a cold/infection and therefore decided to join me for every second 400m. He was also recovering from his efforts at the weekend where he took a gold in the 3000m and a silver in the 1500m in the M50 category at the AAI county track championship.
Having done 400s for the previous 2 weeks building up from 6 to 8 and now to 10, I thought it would be well within my capability. As all lanes were open our target was lane 1 at 80 second reps and similar recoveries. Piece of piss:
1 - 79 (with Pat - no problem)
2 - 78 (good)
3 - 78 (with Pat - tough)
4 - 78 (this is hard work and i'm not even half way)
5 - 78 (with Pat - my legs are heavy before I start, have to push to keep up)
6 - 79 (I can't see how i'm going to last the full 10 without slowing down)
7 - 78 (With Pat - he's pushing ahead of me and I struggle to keep up)
8 - 80 (This is getting very uncomfortable - can I stop now)
9 - 79 (With Pat - that's it, i'm spent i'll just push hard on the last one but not kill myself)
10-79 (Pat joins me and I have to dig deep over the last 100 so as not to fall off the pace - i'm on my knees at the end).
The faster the speedwork that harder the pain but surprisingly the quicker the recovery - My legs felt fresh coming away from the track.
I checked my log to see if I had done sessions like this before and found that while I had completed similarly fast 400's in the past my recoveries were longer, typically 400m at a slow jog (at least double the time of the fast rep).
According to Daniels Running Formula if I were running Intervals (I-Pace) my target pace should be slower - about 86/87 second laps (as for my longer 1k Intervals) and my recoveries shorter (i.e. start every 400m on 2 minutes or 2:10) with the aim of maximising my time running at VO2max. I-Pace should be the same no matter what the distance. On the other hand if I were running Repetitions (R-Pace) my target pace at 80 seconds would be correct but my recoveries should be long enough until "you feel you can perform the next run as well as you did the previous one". A general rule is that recovery should take between twice and four times as long as the fast rep. The purpose of R-Pace, which is primarily anaerobic running, is to improve economy and speed. So while I was running at R-Pace I wasn't allowing myself sufficient recoveries to get the full benefit and while my times did not get progressively slower the stress on my body got progressively more intense - hence the hands on knees exhausted feeling after the final rep. Certainly felt tougher than Tuesday's 4 x 1000m Intervals @ 87 second laps (90 in lane 3)