Ask Stew: How to Go Easy on the Knees to Drop 20 Pounds

As we age, non-impact cardio options start to become favorites, especially if the knees are aching and the body is carrying around more weight than is ideal. There are many non-impact, joint-friendly exercises you can find to stay active. They just may be a bit different than the workouts you are used to doing.

As I age, I am finding that swimming and yoga-based stretching are much better for me, especially when compared to the lifting and running that I have done for decades. Though I still lift and run, the added non-impact cardio options and flexibility training are things that I cannot live without when considering age and previous injuries.

Stew, I am about to invest in either a rowing machine or stationary bike. Which is better on the knees? I used to run, but I put on some weight and now even walking hurts. What do you recommend as options that will not hurt my knees and help me lose weight as I look to shed 20 pounds? Thanks, Kelly

Kelly, you are correct to try a non-impact option for a while and avoid the impact of extra weight on the knees while you try to lose weight. If you were not having pain, I would say keep walking.

But I have a saying I use in coaching as well as my own training. "If it hurts to run, stop running. If it hurts to walk, don't run (or walk). And if it hurts doing nothing (sitting or standing), go to a doctor or physical therapist."

Typically, pain in the knees and other parts of the lower extremities can be dealt with by reducing the impact forces on the bones and joints produced by walking and running. My personal favorite non-impact option is swimming, treading or aqua jogging. I tend to do all three in a pool session for a total time of 30-45 minutes.

Another option is the elliptical machine. When my legs are feeling the aches of running cycles and I need a few days off from running, I will replace it with 30 minutes on the elliptical machine and top it off with 30 minutes of swimming and treading. Non-impact cardio is great for the heart and lungs, but the difference is that you have no pain in any joints when you are finished.

To answer your question, what you buy depends on the knee injury. If you are having a hard time with the range of motion of your knees, the rowing machine may be tougher, even though it is a great nonimpact option. Biking just does not require the same range of motion that full rowing strokes do.

If the knee pain results from impact forces, the bike and rowing machine are great land-based, non-impact cardio options. I have both a bike and an elliptical machine in our home gym, but I also have access to a rower and pool. All of these have been helpful when I feel the miles of running taking their toll on my feet, shins, knees and hips.

Here are a few ideas to use when you decide to row or bike for non-impact cardio options:

Bike Pyramid

Increase resistance every minute on the minute (EMOM) by one level until you must stand up to peddle to keep the RPM in the 70- to 90-rpm range. Increase resistance for 10-15 minutes and then repeat in reverse order for a 20- to 30-minute total workout complete with speed maintenance at varying resistance. If you decide to get a Peloton type of bike, you have access to countless spin classes if you need some coaching motivation.

Bike or Row Tabata Intervals

The Tabata interval is a 20-second sprint, 10-second easy interval that you work hard to maintain for 5-7 minutes. Then take 2-3 minutes of an easy ride or row and repeat a few more times for 20-30 minutes. There are many online rowing coaches, like the spin class bike workouts, at Hydrow.com.

Regardless of the non-impact option you choose for your home gym, the key is consistency. Block out a time of the day and get it done. Make an appointment for yourself, and soon that habit will be your time that you can't live without. Consistency equals results.

Stew Smith is a former Navy SEAL and fitness author certified as a Strength and Conditioning Specialist (CSCS) with the National Strength and Conditioning Association. Visit his Fitness eBook store if you're looking to start a workout program to create a healthy lifestyle. Send your fitness questions to stew@stewsmith.com.

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