Marathon Training Progress

For fourteen months I ran at 49.3–49.4% left, which is about as even as a person gets. Since returning from the IT band layoff I am at 47.7%, and correcting for the fact that slower running shifts this a little, I am still roughly 1.4 points short of my own baseline. Over the last 3 weeks it has held flat rather than closing. The knee has read 0/10 for almost all of it, non-zero on two days: worst 4/10 after a 5K time trial, and most recently 2/10 after a strength session, each resolving within a day or two. It has been back to 0/10 for the 36 days since. That mostly quiet record is the point: a limp you cannot feel is still a limp, and the other leg and both hips absorb whatever the left one is not taking. What I do about it: lead every single-leg exercise with the left leg so it is never the tired one, and match the left side's quality rather than counting reps. This number is the thing I check weekly.

The same warm-up curve shows up in the asymmetry itself. Averaged across the comeback, the left leg carries 47.5% of footstrike time in the first kilometre and climbs to 48.1% by the sixth, moving back toward even as the tissue warms and the pace lifts. On any single long run the swing is larger still. The left side loads better the longer I run, not worse, so the deficit is an early-run, cold-tissue problem rather than fatigue. What I do about it: the same ankle hops and skips that warm the tendons also help the balance, and I keep the first kilometre genuinely easy so the left leg has time to switch on before the load builds.

Braking at footstrike starts at 8.1% and falls to 4.6% by the sixth kilometre, and this is after a five minute walking warmup. The obvious reading is overstriding, but my own numbers say otherwise: across these laps the kilometres with the longest stride and the lowest cadence are the ones that brake least. What actually predicts it is how far into the run I am. This is cold tendon, not bad form. The Achilles and the plantar fascia are not returning energy yet, so landing force gets absorbed instead of bounced back. What I do about it: three or four minutes of ankle hops, pogo hops and skips before the watch starts, then let the first kilometre be slow instead of chasing pace in it.

These are the same six kilometres measured two ways, and they move in opposite directions: turnover drops from 88.4 to 86.5 steps per minute while each step stretches from 0.86 to 0.94 metres. All the late-run speed comes from reaching further rather than turning over faster. Worth watching, but not worth panicking about, because the braking chart above says those long-stride kilometres are my cleanest. What I do about it: the real limiter on the back half is cardiac, not mechanical, so I hold a heart-rate ceiling of 152 and let the pace fall where it wants to.

Set against a full year of base training, almost everything has improved: quicker turnover, less time on the ground, less wasted vertical bounce. The engine and the mechanics are both in better shape than they were before I got hurt. One more thing that surprised me: on the day I actually flared the IT band, a hard time trial in August, my form metrics were the best of the entire comeback: 49.65% balance, 89.33 steps per minute, 235 ms on the ground. Technique did not break down. The dose was simply too big, 356 W against about 275 on an easy day. What I do about it: keep the fast work short and well recovered, and stay strict about sustained hard running.

The cap holds on most flat ground and gives way on the hill. 111 of 136 flat or downhill kilometres finished at or under 152, while 14 of 20 climbing kilometres went over it, averaging 153 bpm. Near the cap, pace on those climbs (6:16/km) is within 2 seconds of pace on the flat (6:14/km): I hold the pace up the hill and let the heart rate take it. That is allowed by design, since the hill is short and the rule is to stay under 164, but it is where the cap does the least governing.

Every run so far started between 8 and 29 C, with dew points of 6–24 C. Already the cooler mornings run 29 seconds per kilometre faster at the same heart rate (5:55 at under 15 C vs 6:24 at 25 C and up). Expect the gold to darken and the marks to rise as it keeps cooling.