"Tightening the muscles above the knees helps lift them," says Johanna Subotovsky, a trainer at Equinox Fitness. To boost quadriceps strength, sit at the edge of a chair and extend each leg until it's parallel to the floor.
The only way to fully restore knees to their former glory involves surgery: No thanks. A less-invasive option could be coming soon. Doctors are investigating laser and radiofrequency treatments (brands include Titan and Thermage) as potential knee-lifters. These procedures heat collagen, causing it to contract and tighten skin over time; one treatment (about $3,000 for both knees) is supposed to yield results over six months, and the effects can last up to two years. "I'm not confident in these treatments yet, but as the technology evolves, the knees will be an area that could be treated successfully," says Ranella Hirsch, MD, president of the American Society of Cosmetic Dermatology & Aesthetic Surgery.