While a modern total knee replacement (TKR) allows for a return to an active lifestyle, there are certain high-impact activities that orthopedic surgeons generally advise against to prevent premature wear or "loosening" of the prosthetic joint. You should never engage in high-impact sports like long-distance running, jogging on hard surfaces, or singles tennis, as the repetitive "pounding" force can degrade the plastic (polyethylene) spacer between the metal components. Contact sports like football, rugby, or basketball are also discouraged due to the risk of sudden twisting or falling, which could fracture the bone around the implant. Additionally, many patients find that kneeling directly on hard surfaces is permanently uncomfortable or prohibited without thick padding, as it puts direct pressure on the patella component. While you can hike, swim, cycle, and play golf, the goal is to avoid "explosive" movements that exceed the mechanical limits of the artificial knee, ensuring the implant lasts for its intended 15 to 25-year lifespan.