Knees are complex joints, and with this complexity comes the myth that the bones, tendons, ligaments, and cartilaginous tissues that flex, extend, and propel you in all directions are destined to deteriorate — destined for discomfort, for pain, for immobility, for surgery.
Yet even if you are an avid athlete or have a family history of knee issues, you are not — repeat, not — doomed to suffer from damaged knees.
In fact, experts agree that the fate of your knees is not entirely predestined. They won’t necessarily wear out, and even existing knee irritation can be healed. Growing older is not an automatic life sentence to such complaints as osteoarthritis, rheumatoid arthritis, bursitis, tendinitis, or runner’s knee.
“If you’ve been told it’s normal for your knees to feel crummy when you get older, you’ve been misled,” says strength coach and prehab specialist Kate Galliett, BS, FRCms, NASM-CES, creator of the Unbreakable Body program.
Many of the joint issues we consider chronic and a result of aging can be prevented or ameliorated, she says, by strengthening and mobilizing the entire leg: hip to foot and everything in between.
Surgical intervention may ultimately be in the cards for you — some 4.7 million Americans are living with total knee replacement. Still, having the operation with your knees in their best shape possible will increase your chances of success and long-term resiliency. (For more on replacement surgery, see “Do You Really Need a New Knee?” on page 13.)
Here, experts shine a light on the knee, its intricate movements, and common complaints that may arise from overuse, acute impact, repetitive movement, a sedentary lifestyle, and the simple passage of time. Plus, they share insights on caring for your knees to keep them in action for the long haul.
The Links That Bind Us
Critical to understanding the knee joint is learning about what is known as the kinetic chain: the integration of bones, joints, nerves, and muscles that work together to move the body.
The knee joint consists of four bones as well as tendons and ligaments that keep the femur (thighbone) and tibia (shinbone) stable and aligned, explains Debbie Lensing, DPT, OCS, Cert-DN, a physical therapist at Life Time’s LifeClinic in Chanhassen, Minn., who specializes in lower-body biomechanics and injuries.
The two bones of the lower leg — the tibia and fibula — join the knee to the ankle and foot downstream; via the femur, it’s linked upstream to the hips, spine, rib cage, shoulders, and neck. This kinetic chain offers a holistic view of the knee and everything it affects — and is affected by.
“At a basic level, your knee is a hinge joint,” says guild-certified Feldenkrais instructor Nick Strauss-Klein, GCFP. That means it works to extend (straighten) and flex (bend) your leg.
“But the knee is more sophisticated than that,” he explains. “A knee is not just a hinge; it’s a connection of four bones that also give the knee rotational abilities. The knee has movement possibilities besides the ones we’re most commonly aware of.”
Our knees are natural works of art. They maintain stability and alignment, absorb shock from our every step and jump, and allow us to change direction on a whim. They power our activities and bear the brunt of repetitive and high-impact motions — and they suffer the consequences of our sedentary lifestyles.
Weakness in the knees affects the structures above and below. This means that foot or lower-back complaints may stem from knee issues. Meanwhile, the cause of knee pain may not be as straightforward as a problem in the knee joint itself, but it may originate in the feet or hips.
In fact, foot and hip dysfunction — common results of too much sitting and poor shoe choices — may manifest as knee pain before issues arise in the feet and hips themselves.
Notably, a sedentary lifestyle has been shown to take a higher toll on knee health than the higher-impact exercises that many people with knee problems fear.
“When we’re sedentary and our knees don’t experience a lot of surface variety and force going through them, they become numb to experience and sensation,” Strauss-Klein says. Then, when you do stand up — or walk, run, jump, or squat — your knees (as well as your body’s other muscles and joints) may have forgotten how to move or absorb that force.
The key to healthy knees is to train them to accommodate the forces they are naturally designed to absorb.
The Kinetic Chain
Your primary hip muscles include the glutes (gluteus maximus, medius, and minimus), hip flexors (a group of muscles that allow you to lift your leg), adductors (the inner-thigh muscles that bring your legs together), and the tensor fasciae latae, or TFL. The TFL, gluteus medius, and gluteus minimus make up the abductors (the outer hip muscles that move the leg away from the body and help it rotate at the hip joint).
Weakness or instability in the hips can cause problems with your knees. Though it’s easy to blame a sedentary lifestyle for hip weakness, even active people may have weaker hips than they realize.
Pay attention to your glutes, especially if you’re experiencing knee discomfort or pain, says physical therapist Debbie Lensing. The gluteus medius and minimus, the side-butt muscles, play a major role in stabilizing your knees. If they aren’t strong enough, other muscles and joints must compensate; that burden often gets offloaded onto the knees, increasing impact. Over time, this added pressure can lead to inflammatory conditions, including patellofemoral pain syndrome (known as runner’s knee) and iliotibial (IT) band syndrome.
Each knee consists of four bones, including the knee cap (the patella); tendons and ligaments that keep the femur and tibia stable and aligned; and two pieces of cartilage (the lateral and medial menisci) that absorb shock.
Cartilage, a slippery substance that can wear down over time, is typically the culprit in what we consider age- and overuse-related wear and tear. “It’s similar to a car tire,” says Alfredo Arrojas, MD, orthopedic surgeon at Osceola Regional Medical Center in Kissimmee, Fla. “When you have a brand-new tire, it’s got a nice thick tread on it, but as you drive on it for a while, it gets thinner and thinner.
Limiting activities that involve knee flexion, extension, and rotation — no matter how well-intentioned — won’t protect cartilage from wearing out.
“Cartilage health is promoted by healthy activity, so just like being active helps our bones get stronger, exercise stimulates cartilage to be healthy,” Arrojas explains. (Learn more about low-impact training to keep the knees engaged without pain at “The Case for Low-Impact Exercise”.)
Knee health starts at the foot. “That’s where the rubber hits the road,” says Timothy Miller, MD, director of endurance medicine at the Ohio State University Wexner Medical Center. “If there are abnormalities in the foot, it’s eventually going to work its way up the kinetic chain.” And often your knees are the first to suffer.
If your ankles lack mobility, your knees can lock out as you take a step, putting extra stress on joints. And if your arches are weak, your feet and knees may collapse inward as you stand, walk, or run. Over time, this added pressure can cause knee inflammation and pain.
Your Healthy-Knee Plan
Get ahead of knee pain with strength and mobility exercises like the ones below, which work your ankles, legs, and hips. By taking action now, you can prevent injury and age-related pain later on.
Move as much as possible, advises Strauss-Klein. If you have a sedentary job, find ways to stay active throughout the day.
And seek out a variety of surfaces, especially natural surfaces like sand, grass, dirt, and snow. “Varying the terrain you use creates subtle changes in how your tissues respond, which can mitigate overuse injuries,” adds Galliett.
One factor that can help prevent knee pain or alleviate existing knee pain is maintaining a healthy weight: Carrying excess pounds places extra stress on your joints.
It’s not the culprit for all knee pain, though — and weight loss isn’t an automatic fix. Although it may reduce the pressure on your knees, losing weight alone won’t improve your strength or mobility, nor will it mitigate other harmful lifestyle factors.
What you eat also affects your knee health. Anti-inflammatory whole foods can help strengthen all your joints. And these foods — along with exercise — can help you shed extra pounds. (For more information on eating for joint health, visit “Feed Your Joints”.)
6 Moves for Stronger Knees
Mastering mobility, stability, and strength exercises, like these recommended by Life Time’s LifeClinic physical therapist Debbie Lensing, DPT, OCS, Cert-DN, can play a major role in keeping your knees healthy for life. Perform the first two moves every day and the other moves three or four times per week.
Note: If you have moderate knee pain that doesn’t improve after two weeks, consult a physical therapist about targeted treatment. If you can’t walk without limping, suffer from acute knee pain and swelling, or have been diagnosed with a medical condition like osteoarthritis, seek professional help before beginning this program.
1. Mulligan Mobilization With Ankle Movement
This move increases ankle mobility, which helps prevent compensation at the knees when you squat or climb stairs.
- Wrap a resistance band around one ankle below the ankle bone and attach the other end to an anchor behind you. Kneel on the floor on your opposite knee so the foot with the resistance band is planted in front of you and both knees are bent 90 degrees.
- Keeping your lead foot flat on the floor, and with a strong stretch on the band, slowly push your front knee forward as far as you can without lifting your heel off the floor.
- Once you can’t go any farther, pull your front knee back to starting position. Perform 20 reps before switching to the other side. Try to do this move two or three times per day.
- If this move is hard on your back knee, kneel on a yoga mat or blanket.
2. Foam Rolling Quads and Hip Flexors
Loosening your quad and hip-flexor muscles with a foam roller can help release pressure on the knee cap.
- Lie face-down on a foam roller so the roller is horizontal and supports your quad muscles (the muscles in the front of your thighs). Support your upper body with your forearms on the floor.
- Roll back and forth on the foam roller for one to two minutes, going from your hip flexors just below your hip bones to the bottom of your quad muscles just above your knees.
- Aim to roll out two or three times per day, as well as after your workout when your muscles are warm.
3. Single-Leg Bridge With Knee toward Chest
Use this exercise to activate your glute muscles before tackling more challenging glute-focused strength moves. Pulling one knee to your chest at the top of the exercise helps prepare your glute muscles for moves like lunges, split squats, and running, and can be especially helpful to counteract overactive hip flexors.
- Lie on your back with your knees bent and feet hip width apart on the floor.
- Lift one foot off the floor to bring your knee toward your chest. Interlace your fingers beneath your knee to help guide it gently as far as you can without sacrificing form.
- Push through your heel and squeeze your glutes to lift your hips off the floor.
- Hold briefly before returning your hips to the floor. You should feel this move primarily in your glutes, and minimally in your hamstrings and lower back.
- Perform two or three sets of 20 reps per side. If this move is too challenging, start by simply raising one foot off the floor from bridge position. Or keep both feet on the floor until you’re ready to try the single-leg version.
4. Banded Lateral Walk
Strengthen your side-butt muscles to shore up hip stability and prevent your knees from collapsing inward while running or squatting.
- Stand with legs hip width apart and loop a resistance band around your ankles below the bone. You should feel mild to moderate tension in the band.
- Bend your knees slightly and step one foot to the side. Immediately follow with the opposite foot so your legs are once again hip width apart. Continue stepping in the same direction for 20 steps total, then repeat in the opposite direction. Perform two or three sets.
- Keep your torso steady as you side-step to avoid rocking motions. To make the move easier, use a band with less resistance, take smaller steps, or move the band up above the knees. To make the move more challenging, use a heavier resistance band, take wider steps, or loop the band around your forefeet.
5. Single-Leg Box Squat
Runners in particular will benefit from mastering this squat. “You’re leaping from one leg to another repeatedly, sometimes for 13.1 to 26.2 miles,” Lensing explains. But even if you’re not a runner, the single-leg squat will assist you in building glute strength and overall balance, which helps offload pressure from your knees.
- Set up a box or bench one foot behind you. The surface height will depend on how deep you’re able to squat comfortably and with control, so start with a higher surface and adjust as needed.
- Shift your weight onto one leg and lift the opposite foot a few inches off the floor in front of you.
- Push your butt back and bend your standing knee to sit back into your hips. Tap the box or bench with your butt, then push through your standing foot to return to starting position. Perform two or three sets of 15 reps per leg.
- Keep your stance knee in line with your toes; don’t let your knee travel in front of your toes or collapse inward or outward.
- Gradually lower the box or bench height until you’re able to squat at full depth (thighs at or below parallel to the floor). To make the move easier, raise the box or bench height, or kickstand your opposite foot to help you balance.
6. Single-Leg Squat reach
Once you’ve mastered the single-leg box squat, progress to this next-level version that incorporates a functional rotational movement. This single-leg move will challenge you to keep your knee steady while you rotate, which is especially helpful for people who run or play rotational sports like baseball or tennis.
- Stand with feet hip width apart and arms at your sides. Shift your weight onto one leg and lift your opposite foot off the floor a few inches behind you. Push your butt back and bend your standing knee to sit back into your hips.
- Keeping your back flat and knee in line with your toes, reach your opposite hand toward the outside of the standing foot. Return to standing, then reach your other hand to the inside of your standing foot.
- Perform 10 reaches per hand on one leg before switching to the other. Do two or three sets.
- To make the move easier, place a slider or folded towel under your back foot and simply slide it backward instead of lifting it off the floor. To make the move more challenging, reach while holding 5 to 10 pounds in each hand.
This originally appeared as “Knee Know-How” in the December 2019 print issue of Experience Life.