If you’re struggling with patellar tendonitis, patellafemoral syndrome, patellar tendinopathy, or a total knee replacement, this may help eccentrically strengthen the patella tendon.
Rather like developing a pistol squat note two kettle on floor, 4 counts down, 1 to return. Develop to toe touch then single leg.
Usual disclaimer, not ideal for acute situations if in pain during, stop and see your preferred osteopath, physiotherapy, orchiropractor