I was searching what people had to say about the impact of long running on sprinting/raw speed. And the basic gist is that for a sprinter a long run is not useful at all, and so they don't do it.
However I can't find a conclusive answer as to if it's just not useful for speed and won't make you faster (on 100-400m), or if it actually also slow you down and make you less fast.
Thank you,
If you stay up on regular speed work I doubt it affects it too negatively. I just finished an 80-mile, zero-carb week, my highest in 13 years, and jumped on the track for some 100s and ran as fast as last summer when I was hitting speed multiple times/week. YMMV, try it out and see for yourself.
I always found throughout high school I was always .5-1 a sec in faster for 100m after cross country, doing absolutely NO sprinting for months, and relatively high mileage compared to track. Just don’t do 100 mile weeks.