Grrr.... I think I have patellar tendonitis. Here's the long story: I began doing squats and lunges back in August. My chiropractor warned me that they could hurt my knees, I countered with a bunch of info that squats were not bad for knees, and we came to an agreement that I would skip the lunges and not squat with heavy weight, at least not for a while. One day after seeing him (last month) my right knee began to hurt. Now they both hurt. The pain is below the knee, at the top of the tibia. After reading about it, my best guess is patellar tendonitis, although chondromalacia is also a possibility (I have no clicked or grating in my knees, though).
I stopped all lunges and squats. At the same time, I began doing the Body by Science workouts, and started heavy leg presses. That aggravated my knees. I decided to try static contraction leg presses (much more weight with very little range of motion, hold the weight steady). This confused me. The first time I tried this, I upped the weight more and more until the plates weren't even numbered any more. Counting the plates, I was up to 410 pounds, and it didn't feel like my legs were really working. My back didn't like it, and I was almost being pushed up out of my seat, so I stopped. The next week I gave it another try, and held 410 pounds for 2 minutes. My knees hurt a lot later that day. I had also done tabata sprints on a recumbent bike, which I suppose could have aggravated them too.
Sorry for the long post. I want to work my legs, but how???
Short answer - I don't know, apart from your standard "non weight bearing" such as swimming.
Also having someone check your form when you're doing these things. E.g. the machinery I use at work (tractors etc) is designed for lanky men so I stretch to reach pedals. If I'm not careful to align my leg with the clutch, it KILLS my knee after a few minutes. And that's only a clutch, not 410 lbs
I'd say get it checked and make sure it is what you think it is. If it is, does it heal after so many months off exercise, or is it chronic? Because that would affect your best course of action.
Also I've never used "static contraction" in this context but is it possible you went too high too quickly in upping the weight?
I've never done a static hold longer than 15 seconds. I find the leg press is not a good machine because you have to start in a weaker leverage position, then go into the stonger position for the static hold. I do like the leg press for BBS workouts.
I was using a squat and dead lift in a power cage, so that the leg action was about 1" to the static hold.
But I didn't have bad knees to begin with. I quit the leg exercises when I aggrevated my achilles tendon, but I'm back at it now with my legs. I still wouldn't run any sprints yet, but I am back to doing 4 x 30 second "sprints' on a stationary bike, twice a week.
Tendons take a long time to heel. The first suggestion I have is lots of rest for those joints. The only other thought is try isometric. If it continues to aggrvate then stop immediately.
The reason I held it so long is that a short time felt so easy. I was doing 130 pounds using the slow BBS method, so I was surprised that I could go up so much in weight without it being difficult. I was really loving squats, and I'm sad to not be able to do the workouts I want!
I really liked the squats too. I was finding the concentrated load was hurting the back of my neck if I didn't get the position of the bar just right.
I'm going to use static holds as my main strength test. I'll do one just before Christmas. I like the idea of strength test adding to ones strength.
I'll do the BBS until the end of January. Then in February I'll add components of continuous fatigue training to strengthen my joints to the BBS format.
My concept is based on the idea that an inactive old guy like me, needed to rebuild fast twitch muscle first to achieve some muscle balance. The static did a great start. Now I'm working with less weight and a bit more range to bring the balance of fast twitch and slow twitch closer. By the end of January I'm thinking I'll have gained enough muscle support I can add the strengthing of the joints which are rapid movements with no weights done before and after the BBS drill.
This concept in theory should reduce some muscle growth, but provide me with a more functional body.