“As we age, skin cells turn over more slowly,” says Jessica Wu, MD, a dermatologist in Los Angeles. And because these areas are always rubbing up against something—your clothes, your desk, your kitchen counter—dead skin tends to build up and get thick, rough, and discolored, she says. Worse, a natural loss of collagen and elastic tissue can cause sagging, especially around joints, where skin is constantly being stretched and contracted. But don’t give up just yet. There are simple, super-effective tactics to target these problem spots, and you can do them all at home. Here, top dermatologists prescribe your DIY game plan.

  1. Add acids to your routineThe problem: Your elbow and knee skin is likely to look dull and rough as you age, thanks to the thick buildup of dead skin on its surface. An alpha hydroxy acid (AHA) such as glycolic acid will loosen up the glue-like protein that holds those cells together so they can be shed, says Elizabeth Tanzi, co-director of The Washington Institute of Dermatologic Laser Surgery in DC. Think of those skin cells as bricks, says Tanzi. “If you dissolve the concrete in between the bricks, they can be removed easily.” With regular use, the skin in these spots will get softer, smoother, and more youthful-looking.The plan: Because these thick-skinned joints can handle a stronger dose of glycolic acid than what you typically find in facial treatments, Tanzi suggests using one that contains 12 to 20% AHA. “Apply it before bed every other night at first, and if there’s no irritation after two weeks, increase the frequency to every night,” she says. In the shower you can exfoliate with a washcloth or a gentle scrub to help the sloughing process along. Try DCL Glycolic Acid Pads 20% Mini-Peel Treatment ($52, dermstore.com).
  2. Upgrade your moisturizerThe problem:The plan:amazon.com Your regular body lotion can’t quite cut through the dead skin cells to rehab cracked, sandpaper-y elbows and knees. For real results, upgrade to a formula that contains urea, a powerful humectant that simultaneously hydrates and loosens the intracellular protein holding dead skin in place, says Tanzi. Use a lotion that contains 20 to 40% urea twice a day for smoother skin in one to two weeks. Try Udderly Smooth Extra Care 20 Cream, ($10, ), which is 20% urea but gentle enough to use on your entire body. MORE: 5 Ingredients To Avoid If You Have Dry Skin
  3. Shake the shady lookThe problem: Constant friction or pressure on your joints—leaning your elbows on your desk as you type, performing gym exercises on your knees—causes low-grade inflammation that triggers hyperpigmentation, explains Joshua Zeichner, MD, director of cosmetic and clinical research in dermatology at Mount Sinai Hospital’s Department of Dermatology in New York City. The result: a dark, shadowy look that’s far from youthful. “It’s more noticeable in patients in their 40s and beyond, because discoloration takes a while to build up,” says Zeichner.The plan: Lighten pigmentation caused by chronic rubbing with a 1% topical hydrocortisone ointment, available at drugstores, twice a day for two weeks to calm inflammation. This will reduce darkness over time, but it can take months to see results, says Zeichner. You can speed up the process with an OTC skin lightener; look for one that contains 2% hydroquinone. The bleaching agent is known to be irritating on facial skin, but dermatologists say the thick skin on your knees and elbows can handle the ingredient. Use it nightly until skin tone improves. Try Ambi Fade Cream ($6.50, shopambi.com).
  4. Cut down on creasesThe problem: Like skin everywhere else, elbow and knee skin also slackens with age. Anti-aging ingredients proven to rev up collagen production—retinol, peptides, and growth factors—can firm and strengthen the skin on these areas over time. “There are some body treatments that contain these ingredients, but there’s no reason you can’t apply your face products to your elbows and knees, too,” says Zeichner.The plan: You’ll need to apply the collagen-stimulating ingredient daily for a few months, but the end game (smoother, firmer skin) is worth the wait: Look for a product that contains between 0.5 and 1% retinol, like Paula’s Choice Clinical 1% Retinol Treatment ($55, paulaschoice.com). MORE: 5 Ways To Get Firmer Skin On Any Budget
  5. Pump some ironThe problem:The plan:Fitness ManagementStronger Knees In 3 Easy Moves3 At-Home Workouts For Sexy, Shapely Arms Loss of muscle and bone mass can contribute to sagging around these areas, says Wu. “Weight training will encourage tautness by keeping your bones strong and producing muscle definition to better support the skin,” she says. Research in suggests that strength training your arms and legs two to three times a week is enough to increase muscle mass and slow bone loss in as little as 10 weeks. Try these workouts: and .
  6. Get your caffeine fixThe problem: Cellulite happens to women of all ages, but it can get worse as time goes on—especially around the sag-prone knee area, says Wu. “Cellulite is the result of fat pockets bulging through the skin,” she says. “As skin gets thinner and collagen gets looser, those fat bulges become more visible.“The plan: While no topical treatment will get rid of cellulite for good, recent research in Drug Development and Independent Pharmacy suggests that caffeine can help reduce its appearance by inducing lipolysis, or fat cell death. “Caffeine has a temporary smoothing effect by increasing circulation and decreasing fat accumulation in fat cells,” Wu adds. Apply a caffeine-containing treatment, like Vichy Celludestock ($40, vichyusa.com), which contains 5% pure caffeine, twice daily.
  7. Ditch the crash dietThe problem:The plan: When it comes to miracle diets, there’s a lot to be skeptical of. In addition to their dubious claims, they can also encourage skin sagginess. “As you get older and collagen and elastin production dips, drastic fluctuations in weight can leave the skin on your legs looking like deflated balloons,” says Zeichner. “That loose skin tends to hang over the knees,” he says. To prevent this weight loss-induced elbow and knee sagging, aim for steady loss—one to two pounds a week—which will allow your skin to shrink back on its own, says Wu. Bonus: your slow-and-steady method will ensure you lose fat, not muscle, and keep your metabolism from doing the nose-dive that comes with calorie deprivation, says George L. Blackburn, MD, PhD, associate director of the division of nutrition at Harvard Medical School. MORE: 10 Moves That Target Cellulite