if you were to ride 500 miles over 5 rides, or 40 rides, would you get the same fitness benefits?

I’m personally if the opinion little and often is better than long and infrequent.

My 5 days commute of 15 miles each day seemed to put me in a better fitness than the Sunday riding clocking ~70miles.

5 days does throw a spanner in the works though, I have felt mega fit (and hungry!) after biking holidays

There that’s cleared things up

Depends 100 miles at 8 mph on a road is not going to get you fit
Secondly if you can ride 100 miles you are fit anyway so the issue is do you want to be able to
1) ride faster
2) ride further


How you train depends on what you want to achieve

IANAFG* but back in the day when I used to actually train, loads of short rides at high intensity were way better for me than plugging along for six hours to build what the cognoscenti would refer to as a "base".


* I Am Not A Fitness Guru

For me, shorter rides of higher intensity - combined with the odd longer one - seem to be the best training strategy. Last year I did lots of long rides to prepare for a Cairngorms Loop ITT attempt. I got round the loop but felt thoroughly beaten up afterwards and it took me a long time to recover.

This year I rode a route with similar stats as an ITT and felt so much better during and after. This followed lots of short high-intensity rides just because that's all I've been able to do for the several months of lockdown.

It was an eye-opener for me to see how well I could get in condition for a 300km effort doing mainly 20-50km rides. I only rode three 100km+ rides in the months beforehand.

Your mileage may literally vary though