In my experience, less but structured workouts are a lot better. How many hours do you normally ride, and how structured is your training? At one time, I would ride 6.5 hours just on group rides over the weekend and on Tuesdays, with intervals on Thursdays and easy endurance rides on Wednesdays and Fridays for 2 hours. That worked out to about 12 hours of training.
Iāve shifted to intervals on Tuesdays and Thursdays, with a hard group ride where I take hard pulls and attack the sprints. I also do one long solo endurance ride of 2.5 hours and spend 30 minutes on Fridays working on my aero position and drops. This has made me a lot better, and I hardly ever fail on workouts. Plus, I have a lot more time to recover and Iām not nearly as hungry.
You have to trust the system. You can use the extra hours off the bike for yoga and lifting. That will give you a lot more than just a bunch of wasted time on the bike. Eight hours is a lot of time for a non-pro rider. If you use most of that time for structured training, youāll get a huge bang for your buck compared to most people who just ride hard in group rides with a lot of freewheeling and off-and-on efforts.
Iām not a gravel rider, but watching the sport and focusing on speed and interval training will make the most difference.
Good luck!