A 30-second test with nothing but a chair can tell you whether you'll be independent or dependent at 80. Most people score lower than they expect and don't find out until something goes wrong. Here's the stat that stopped me cold: for older adults, the hip often breaks before the fall. The bone gives out first. The fall is what happens next. And most doctors never mention it. UK physiotherapist Will Harlow breaks down why your knee pain usually isn't coming from your knee, how even people in their 90s rebuilt leg strength by 175% in eight weeks, and the one movement test that predicts your longevity better than most bloodwork panels.