How do 400 runners transform short-distance improvements into a faster get-out that they can sustain?
I've been working on my 200 speed and making good progress, but it hasn't carried over to my 400 much. Both have improved by about .6 seconds over last month, but the 400 is an outlier.
I've been hitting the 200 split at nearly 2 seconds slower than 200 max. To get out faster than that, my form changes drastically leading to burnout soon after 200. A couple of times I've started faster and caught myself altering my form from on the second turn, like a power sprinter who converts to middle distance halfway. I expect this has something to do with alactic metabolism, muscle types and whatnot, so that however they work over 200 doesn't convert to 400.
I'm guessing I should train to recruit more aerobic-using muscles for acceleration, like starts with short recovery. But let's see what the sprint coaches say.