WADA has restrictions on Prednisone: "...Prednisolone & prednisone within 10 days of a competition." https://www.usada.org/spirit-of-sport/key-changes-2022-prohi...

"...Oral corticosteroids reduce the pain and inflammation that often occurs with extreme exertion. Athletes have reported that corticosteroids help them push through the pain of extreme exertion and allow them to recover faster for the next event..." https://truesport.org/clean-sport/5-facts-about-corticostero...

Painkillers and anti-inflammatories are usually taken to shorten recovery time. It's usually a sign that an athlete can't keep up due to old age/injury or, if many athletes are using them, because the sport has an unrealisticly busy calendar.