Posted: 23/05/2012 at 22:05
Wrt 400s, think Rob is spot on with his suggestions. As for the sorts of times, the longest I did was 20 x 400, 45 secs rest in 77 s. Not too bad because it goes so fast!
Bus, you could always go for an alternating 60, 90 and aim for the same pace, and then go 60, 60, 90 and so on. Takes longer but maybe a lower injury risk if you transition over a few weeks?
One of my suggestions was to continue aiming for under 80s, maintain the same recoveries, and swap say 16 x 400 with 14 x 500, then 12 x 600, 8 x 800, 6 x 1k, 5 x 1200... you get the idea. I think reducing the cumulative recovery should probably be the aim, but what people tend to do is repeat the same sessions and try to shave a few seconds off each time!