My mate at work is always covering lots of road miles, but he is not very fit. I suggest that it is the easy option…
Suggest away 😀
Road cycling is ‘easier’ in as much as you’re not fighting the terrain, and therefor don’t require some great heavy lump of a bike to help you. Because of this, you go faster, or you go longer, or you go hillier.
Because of this you get fitter, because you can actually get on with propelling yourself as fast as possible. The joy of actually riding a bike which is uncomprimisingly fast (and as a side note, doesn’t require a complete overhaul every couple of weeks) is a nice novelty compared to MTBs as well.
If pure speed on tarmac wasn’t fun, why would people buy fast cars or motorbikes?