If you just Completed the 75 Episode Anime AND BOTH the TV Movie (Champion Road) and OVA:
You will want to continue with Volume 35 - Round 315.
If you just Completed the 75 Episode Anime:
You will want to continue with Volume 31 - Round 269, the day right after
If you just Completed the 75 Episode Anime AND ONLY the TV Movie (Champion Road):
If you choose not to or are unable to watch the OVA, you will want to continue with the
fight which spans from Volume 31 - Round 270 through Volume 33 - Round 289 and then, after reading that, you will want to skip to Volume 35 - Round 315.
If you just Completed the 75 Episode Anime AND ONLY the OVA (Mashiba vs. Kimura):
If you choose not to or are unable to watch the TV Movie,
Volume 33 - Round 290 through Volume 35 - Round 314.