It would be awesome if you knew of some literature on why open chain isokinetic exercises are better for patella grafts than closed chain exercises, since according to most of what I read, open chain extension exercises usually put way more strain on the ACL than closed chain exercises like squats.
Stop using machines!
- Thread starter Ride_On
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Open-chain isotonic exercises often place excessive stress on the patella, primarily due to the fact that muscle tension is the same throughout the exercise. Standard leg extensions, as well as the majority of lifestyle activities are considered isotonic in nature. Isokinetic, allows for variance in both tension and length, making it lower impact than closed chain exercises.
But that's also why isokinetic systems are so expensive, and not as accessible.
But that's also why isokinetic systems are so expensive, and not as accessible.
standard leg extensions aren't isotonic, though.. no real exercise is.. to get an exercise to be isotonic I think you need a dynamometer and set it to give the same amount of torque throughout the movement, so that the movement speed will vary (IE, speed will go up in the parts of the ROM where the subject is strong, making the force less because of the force velocity relationship)
Just because the external resistance is constant doesn't mean the muscle contraction force is constant. They used to call regular strength training isotonic before, but now they use something like constant external resistance.
Using a dynamometer set at a relatively high velocity would mean lower joint forces than a slower dynamometer velocity or a heavy set of regular leg extensions, though, so that could be it.
Just because the external resistance is constant doesn't mean the muscle contraction force is constant. They used to call regular strength training isotonic before, but now they use something like constant external resistance.
Using a dynamometer set at a relatively high velocity would mean lower joint forces than a slower dynamometer velocity or a heavy set of regular leg extensions, though, so that could be it.
Tracked down a couple studies online with some open time here at work:
Both point to isokinetic exercise as an effect part of an overall rehab process. I also read something about isokinetic being prefered in some rehab because it can safely be done through a greater range of motion than other types of exercise during the early rehab stages, but I couldn't access the actual research that the article referred to. I'll try to see if I can access it when I'm at home and post it later.
Both point to isokinetic exercise as an effect part of an overall rehab process. I also read something about isokinetic being prefered in some rehab because it can safely be done through a greater range of motion than other types of exercise during the early rehab stages, but I couldn't access the actual research that the article referred to. I'll try to see if I can access it when I'm at home and post it later.
I can see a benefit of isokinetic exercise is that if pain is experienced at any part in the ROM, you could just decrease your effort; the machine would lower its resistance and you would be able to continue the set instead of having to abort.
I can't find a lot of studies that compare isokinetic exercise to other forms of exercise though, like for example squatting. If the speed itself is the issue, then you could do high speed movements without them being isokinetic.. you wouldn't be able to be precise but if high speed contractions are, for some reason, good for ACL rehabilitation, then you could just as well do low resistance high speed squats or leg extensions.
I think the main reason isokinetic exercise has been tangled into rehabilitation is because isokinetic exercise is a good way to assess strength. At least one definition of strength, but forth by William Kraemer, is that it is velocity specific. It's the maximal force produced at a specific velocity, and you need a dynamometer to assess that.
I can't find a lot of studies that compare isokinetic exercise to other forms of exercise though, like for example squatting. If the speed itself is the issue, then you could do high speed movements without them being isokinetic.. you wouldn't be able to be precise but if high speed contractions are, for some reason, good for ACL rehabilitation, then you could just as well do low resistance high speed squats or leg extensions.
I think the main reason isokinetic exercise has been tangled into rehabilitation is because isokinetic exercise is a good way to assess strength. At least one definition of strength, but forth by William Kraemer, is that it is velocity specific. It's the maximal force produced at a specific velocity, and you need a dynamometer to assess that.
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This thread is out of control
yeah.. I'm a mod derailing a thread.. lol, I should get fired
We're still talking about machines, though. like isokinetic vs squats in rehabilitation.. so it sorta fits under the machine thing.
This thread is out of control
LOL
aint it cool when the braniacs take over!
but do they sweat!
Haha normally I would love it because I would learn something. However, in this case, I was too worried about not getting eatin by you guys in the beginning that I had to focus on my own argument. I'm so far out of the loop in their discussion that it's not even worth entering anymore lol.
yeah.. I'm a mod derailing a thread.. lol, I should get fired
We're still talking about machines, though. like isokinetic vs squats in rehabilitation.. so it sorta fits under the machine thing.
Yeah, I supposed we kinda jumped the shark...