Question: Hi there,

I'm a 35 year old male working to get in better shape. I'm definitely having some success, and while still overweight, am doing well with an exercise program (and have been for ~2 years now).

When I was in high school, I turned to speak to someone while I was carrying a stack of books, and somehow managed to twist and collapse my knee. I was on crutches for some time, but it eventually healed.

Since school but before I started exercising regularly, my knee would occasionally collapse during every day activities. This wasn't often...a few times a year...and I always managed to catch myself, but it was very painful and usually resulted in limping a bit for a day. This had happened while walking, getting up from the floor, or small jumps (ie. jumping off the last step to the ground).

Because of the issue, I went to a physical therapist at my local hospital and learned some exercises I could do to strengthen the knee. These includes squats, pushing back the knee against the floor with my leg muscles, knee bends, and several types of leg lifts that put some gravitation strain on the joints. When first starting therapy, they were every day exercises, and I still do them three times a week. Since starting this program, my knee hasn't collapsed for 2, maybe even 3 years.

The reason I'm telling you all this is I've been working out on a treadmill/incline trainer, and I'm starting to add more time and run more. So far running is always between 3.5 and 5 mph, and I usually spend 30-45 minutes on the treadmill 4 days a week (these are the days I don't do the knee exercises and other types of exercise, but I still do a short stretch beforehand). I also try to walk as much as possible in general. Some days on the treadmill are a lot of running, others mostly walking, as it depends on the incline the map for that day has. (I go by heart rate to determine speed.)

I know the therapy's helped a lot, my knees feel pretty good these days (both of them ache some after a lot of walking/running, but nothing that seems abnormal), and I've read that walking/running/climbing can even strengthen knees. But I do have the horrible thought about what would happen if my knee collapsed during a treadmill run. All that said, I know not using it (as I didn't exercise much when it was collapsing) certainly didn't help the situation, plus I enjoy the running, and it's definitely working to get me in better shape.

Do you feel like this is a safe activity for my knee? Are there any warning signs I should watch for to avoid a knee collapse? Or do you feel like, after a few years and the exercises, collapse is unlikely at this point? Also, will this likely mean my knee will wear out earlier than the norm as I get older?

Thanks very much!

Thank you so much for your feedback and thorough answer!

I'm glad to know that these activities should strengthen, not weaken, my knees. It sound like with any luck I might not have to deal with a buckling knee again should the ligaments be strengthened.

I appreciate the help and will continue to exercise as I have been!