More than not, the reason a non-runner tells me he doesn't run is due to knee pain. "Oh I'd run, but I have bad knees." "My knees just can't take the pounding." It's not just non-runners, though. Former runners will often say the reason they no longer run is due to "bad knees."
Knee problems are often blamed on the constant pounding that a runner does when running. Each time your foot hits the ground the force exerted is about 6 times your body weight. So, if you weight 175lbs, one foot landing in running is taking on about 1000lbs! That's a lot of force! But you know, Mother Nature is a pretty smart cookie. Weren't we designed to walk and run? Okay, maybe she didn't intend for us to run grueling ultramarathons, but shouldn't we be able to handle running 5-10 miles several times a week? The answer is, "Yes!"
So, why do so many of us have knee problems? Well, the problem usually isn't the knee. Knee pain is usually the end result. Earlier this month, I wrote a post on how a
tight ITB (iliotibial band) that runs along the outside of each leg can cause knee pain. Muscle imbalance is another culprit for knee pain.
There are several groups of muscles that support the knee. The two main groups are the quadriceps and the hamstrings. The quads are actually made up of four different muscles—Rectus Femoris, Vastus Lateralis, Vastis Intermedius, and Vastis Medialis. The hamstrings consist of three different muscles—Biceps Femoris, Semitendinosus, and Semimembranosus. Other muscles that help stabilize the knee (but to a lesser degree) include your calf muscles, the hip abductors (outer thigh), the hip adductors (inner thigh), and as mentioned earlier, the iliotibial band.
Okay, that's a lot of muscles with big names and you're wondering how all of that's related to your knee. Well, remember that song you sang in elementary school—"Dem Bones"? You remember
Toe bone connected to the foot bone
Foot bone connected to the leg bone
Leg bone connected to the knee bone...
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Well, your body actually works like that. Nothing in your body really works in isolation, it all works together. But, sometimes there can be an imbalance which will cause other areas to work harder. When this happens, sometimes pain can occur.
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Often knee pain is the result of such an imbalance. Sometimes a runner can have strong hamstrings that overpower his/her weaker quadriceps. When this happens it can cause the patella (knee cap) to be imbalanced resulting in pain. Because the quads are weaker, they're not able to support the knee which can cause the knee cap to twist and pull.
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The opposite can also be true. A runner can have dominant quads which overpower the hamstrings. Your quads are typically stronger than your hamstrings, but they should only be about 25% stronger. Quads that are stronger than this can also cause an imbalance in the support of the knee cap.
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To even further confuse you...you can have an imbalance within your quads. Remember there are 4 different quad muscles. If the inner quad (Vastis Medialis) is stronger, it can pull on the knee cap. If the outer quad (Vastis Lateralis) is stronger, it can pull on the knee cap. Just tight quads in general can also pull the knee towards one side.
So, now that I've fully confused you, what can be done to prevent knee pain. This part isn't as confusing. Just be sure to do a balanced set of quad and hamstring exercises. Runner's don't often go to the gym and when they do, they may hop on the leg extension machine and pop-out a few sets and think that's good. First of all, I don't recommend getting on the leg extension machine. Research has shone that it puts an awful amount or tension and pressure on your knee cap. Your knee's weren't designed to hold that much weight. Think about it. How many times during the course of the day do you naturally extend your knee with 100+ pounds on your feet? Never. The leg extension machine will be adding to your knee pain instead of strengthening your quads.
Exercises good for strengthening your quads and hamstrings include:
• Body-weight, barbell, and/or dumbbell squats—a squat is great for strengthening your glutes, hams, and quads. The deeper the squat, the more the hamstring/glutes are targeted. A quarter squat will target more quad.
• Body-weight, barbell, and/or dumbbell lunges—lunges are great for strengthening your quads. Lunges can be stationary or you can do walking lunges.
• Body-weight, barbell, and/or dumbbell side lunges—side lunges will help strengthen your quads, adductors, glutes, and hamstrings.
• Deadlifts—Deadlifts are one of the best exercises for strengthening your quads, adductors, glutes, and hamstrings. Be sure to use proper technique. Stand in front of the barbell. Squat down and grab the bar using an overhand-grip with one hand and an underhanded-grip with the other hand (this provides a nice secure grip). Your hands should be positioned just outside your legs when you squat down. Keeping your back flat and your head up, stand up with the barbell while pulling your shoulders back. Slowly return the barbell back to the floor, still keeping a straight back and head up. You don't have to do a ton of weight to get benefits from a deadlift.
• Jumpsquats—this simple exercise can be done with just your body weight or you can hold a medicine ball to raise the difficulty level. To do a jumpsquat, simply descend until your thighs are parallel with the floor, then immediately fire upward using your thighs and calf muscles to jump off the floor. Upon landing, immediately go into your next jump. Try doing 3 sets of 15.
• Stability ball leg curls—this looks really simple, but beware! They are killer for your hamstrings! Simply lie on your back (on a mat) with legs extended and your heels resting on top of a stability ball. Your hands should be beside you resting on the floor. Use your heels to pull the ball toward your buttocks. The ball will roll from your heels to the bottom of your feet. Then slowly extend your legs and return the ball to starting position. Try doing 3 sets of 12 reps.
These are just a few of the many exercises that target your hamstrings and quads. The key is balance. If you do an exercise that targets the quads, follow it up with a hamstring exercise. It's also a good idea to have a personal trainer or your running/workout buddy check to make sure that you're using proper technique when doing these exercises, especially the squats and lunges. A key thing to look for when doing a squat or lunge is that your knee does not go past your toe during the squat/lunge. Also, stand in front of your buddy while he/she does a body-weight squat. Check to make sure his/her knee (one or both) is not turning inward during the squat (this is called Valgus Knee). The knee should remain neutral. Also check and make sure that his arch isn't collapsing inward. This inward motion of the arch or knee needs to be addressed before continuing with your squats. A personal trainer can help you correct this. Proper technique is very important with these exercises.