Dear Colin: I have osteoporosis thats worse in my hips. To help increase my bone density, I hike trails at a nature park, usually with a weighted vest, but stopped when my knees started hurting. Are there exercises that would increase my hip bone density without risking fracture and hurting my knees? Bonnie, Portland
While there are potentially effective exercises that can yield remarkable benefits, they must be done correctly to minimize risk of injury to the knee and other joints.
The stationary lunge can simultaneously address your knee pain and osteoporosis, if done correctly and consistently, given its compressive load on bones (which helps increase bone density), caloric expenditure (fights obesity), enhancement of thigh/hip strength (improves knee joint mechanics), improvement of balance (helps prevent falls and fractures) and ease of implementation (little equipment is needed).
If youre new to strengthening, try this exercise near your kitchen counter so you can lightly touch it with one hand for balance. Even if youre an experienced exerciser, work on getting the technique right before adding dumbbells.
In the starting position, your front knee is slightly bent, your back heel off the ground. You should focus on tensing your front thigh and relaxing your back thigh so that little pressure is felt through the back foot. This takes mental skill and time to develop.
In the end point for the down phase, you should be bending the front knee about 50 to 60 degrees while dropping the back knee toward the floor. You should lean forward slightly, keep your hips back, pelvis completely level and knee in line with the toes. Allowing your knee to collapse inward decreases demand on working muscles and is potentially damaging to the knee, hip and ankle; keep the knee straight the entire time.
At the end point for the up phase, focus on tensing the front leg and relaxing the back leg. Sharing your weight equally between both legs will make this exercise far too easy, prompting you to use heavier weight than necessary. Consequently, theres an increased risk of back, shoulder, hip and knee injury.
To minimize exercise time, do the lunge properly and perform 15 to 20 repetitions on one leg, then switch to the other.
Another version is the walking lunge, where you alternate one leg with the other in a walking fashion, which allows muscles to rest between repetitions (which is counterproductive, though, if time is important to you). As a general rule in resistance training, try to maintain tension on working muscles to minimize exercise time while maximizing benefit.
Colin Hoobler is a certified physical therapist and writes a regular column