Blame your joints. A new study found that, on average, Americans over 45 feel 12 years older than their actual age. 55% of those who feel older than their actual age blame joint pain, and 45% said joint pain is limiting how they live their lives. Knee pain, in particular, impacts about 40% of Americans. Those suffering from knee pain have had to make significant lifestyle changes because of it, including where they live (25%), where they work (22%) and how they travel (17%). 85% of Americans experience some sort of joint pain – though half of those don’t realize there is a link between increased muscle strength and reduced joint pain. Less than half (47%) feel optimistic about finding lasting relief from their joint pain.