I am 25 years old. When I am in my top condition for the 1500m/5000m, my natural 400 meter speed is around 53 seconds. This is on about 40 mpw with mostly long tempo runs and long intervals.
I am going to spend 4 months on 400 meter training. How much improvement do you think I could drop? I am hoping for around 49 seconds, but 47 would be nice. Do you think this is possible?