Part of volume is accumulated base, meaning the years of experience before this particular season. It's all part of the adaptation process, where a new racer trains relatively unused muscles into getting fit. If there's been 1,000 hours of prior training, you don't need as much base. So, for me, with (ahem) 29 seasons already under my belt, if I miss out on an hour or three of training right now, well, it won't kill me. Plus, honestly, the season doesn't count as much to me as to a new racer. If I'm not good this year I figure I'll have another year to do it. For someone that just got into racing it'd be really hard to skip riding every weekend (i.e. "a few hours") and still be okay racing, and every race is a new experience so it's exciting and important.

I've tried to do the high intensity, low hours approach, where I'm training (not racing) really, really hard for short intense rides (generally 30-45 minutes long). I found that unless I had a solid base of hours in the winter I wasn't good with just short intense workouts. I need that solid base first, and I need races (most of my races are 1 hr long, give or take, so add 0-60 min warming up and I have 1-2 hours riding on a Sunday).

I've gotten by for a full season, complete with an odd win in a Bethel, plus high places in other races (2nd was the highest), on 150 hours for the whole year. I did about 50 hours in Jan/Feb (about 30+ of them in a training trip to SoCal) and raced after that. Virtually no serious group rides, just races and maybe an hour loop near my house. I raced many of the Tuesdays (1 hour) and some Wednesdays (track racing, maybe an hour of racing).