This episode explores how basic science underpins clinical decision-making in orthopaedics. Using a study of hip and knee joint loads during swimming—measured in patients with instrumented implants—the discussion highlights how biomechanical data can validate long-held assumptions, such as the safety of swimming after arthroplasty. Yet despite their value for hypothesis generation and biological plausibility, preclinical findings don’t always translate cleanly into clinical outcomes, emphasizing the need for rigorous trials, careful blinding, and complementary perspectives.