My main after effects have been saddle sores and still some dexterity and hand strength issues, despite using aero bars for a lot of the time.
In some ways, I feel that being a novice audaxer (who only got a bike <2yrs ago) was helpful this year - I had no preconceptions. I’d taken to heart the advice that I’m pretty sure I saw in here about training/riding in whatever conditions arose, so I’d done some horrendous rides! Rain, cold, heat, even snow… if I’d planned a ride, almost regardless of weather, I did it.
What I also did, in common with most of the south Asian riders (but almost no other brits), was wear long sleeves. I’ve hiked in dessert environments and find that covering skin is cooler than leaving it exposed to the burning sun, as well as protecting it much better than any sunscreen.