Been there! Switching to low-impact cardio like swimming or the elliptical saved my joints while I built up strength. Proper form on squats is a game-changer too—knees tracking over toes, not past them. A good physical therapist can work wonders with targeted exercises if it's a persistent issue.
Spending 10-hour days on concrete subfloors taught me that knee strength comes from adaptation, not avoidance. While elliotbarnes recommends low-impact cardio, I found that controlled, weight-bearing movements like lunges during breaks actually built resilience. Using knee pads with gel inserts helps, but the real fix was strengthening the muscles around the joints through functional work. Now, after a long day, my knees feel solid, not sore, because I trained them to handle the stress.