Last year, F1 switched to ground-effect-based cars which are set up extremely stiff to generate the most downforce. That set-up had the unintended side-effect of porpoising on most cars, with drivers bouncing violently on the straights.
But even without the highly publicised bouncing effect, the low-ride heights have generally made the cars much less comfortable to drive, with more forces transferred to the drivers' backs.
Norris has revealed that last year's McLaren left him in "constant pain", having to do much more work with the team and with his trainer to alleviate his back problems for this year.
"I have to stretch morning and evening, before every session. If I don't then I always struggle a lot more with my back," Norris said.
"It's not just racing. It's just something that I've had to work on in general anyway. But it's definitely not helped by some of the changes on the car over the last couple of years.
"It got to a pretty bad point last year, every day I was struggling with sleep and everything... just in constant pain.
"I think a lot of things have already been put in place like I made a couple of new seats already. It was worse last year than it is this year."
Norris says his recurring issues have also limited how he trains. Even common activities like track walks have been cut down, while he has also had to limit his golf outings.
Source: Autosport