The data supports the anecdotes you’ll hear from me and other players: artificial turf is significantly harder on the body than grass. Based on NFL injury data collected from 2012 to 2018, not only was the contact injury rate for lower extremities higher during practices and games held on artificial turf, NFL players consistently experienced a much higher rate of non-contact lower extremity injuries on turf compared to natural surfaces. Specifically, players have a 28% higher rate of non-contact lower extremity injuries when playing on artificial turf. Of those non-contact injuries, players have a 32% higher rate of non-contact knee injuries on turf and a staggering 69% higher rate of non-contact foot/ankle injuries on turf compared to grass.
https://nflpa.com/posts/only-natural-grass-can-level-the-nfls-playing-field