Jump to content


Isometric Exercise Question


  • You cannot reply to this topic
2 replies to this topic

#1 Quill

    veryCoolRunner

  • Forum Member
  • PipPipPip
  • 157 posts
  • Joined: 22-May 11
  • Sex:Male
  • Location:Adelaide

Posted 05 January 2012 - 07:58 PM

Hey all




I've been doing physio for a month or so after a nasty bout of runner's knee - just the standard-issue squats, split squats, vastus medialis strengthening etc. It's all been going well and I've since progressed from 400m to 2km split by exercise-station stopoff halfway. Just taking it slow and it's a lot nicer to run after even basic strength training (I'm a noob). Heck, it's nice just to run.

Anyhoo, I've been looking to mix it up a bit for my quads as the squats are getting easier and was looking at wall sits. I've tried them and damn. That'll do it. But my question is this: a standard wall sit has the thigh parallel to the floor. This is all well and good, but I've read in many sources isometric holds induce hypertrophy, but only increase functional strength at the joint angle the muscle is trained at. "Essentially, training at only one joint angle does not increase strength throughout the full range of motion (1). In order to improve dynamic power, isometric exercises would have to be performed at multiple joint angles for the same muscle group. This becomes time consuming and enervating for an athlete who may already be spending considerable time on other training modalities."

So what is the functional benefit for us with doing wall sits with the knees bent so far? Would it not make more sense to perform the exercise at the midpoint of your knee's normal range of motion as you run? I tried it and while it's definitely easier, I reached a point reasonably quickly where I was genuinely struggling to hold the position.

Just a question - they definitely seem like they do the job and the point at this stage is still to strengthen and brace the knee, so I suppose they'll get that done regardless.


Thanks guys. :)

Edited by Quill, 05 January 2012 - 08:16 PM.


Support our Australian advertisers:

#2 B+

    1000-club gold-rated CoolRunner

  • Forum Member
  • PipPipPipPipPip
  • 1,063 posts
  • Joined: 18-October 04
  • Sex:Male
  • Location:Penrith

Posted 06 January 2012 - 08:10 AM

View PostQuill, on 05 January 2012 - 07:58 PM, said:

Hey all




I've been doing physio for a month or so after a nasty bout of runner's knee - just the standard-issue squats, split squats, vastus medialis strengthening etc. It's all been going well and I've since progressed from 400m to 2km split by exercise-station stopoff halfway. Just taking it slow and it's a lot nicer to run after even basic strength training (I'm a noob). Heck, it's nice just to run.

Anyhoo, I've been looking to mix it up a bit for my quads as the squats are getting easier and was looking at wall sits. I've tried them and damn. That'll do it. But my question is this: a standard wall sit has the thigh parallel to the floor. This is all well and good, but I've read in many sources isometric holds induce hypertrophy, but only increase functional strength at the joint angle the muscle is trained at. "Essentially, training at only one joint angle does not increase strength throughout the full range of motion (1). In order to improve dynamic power, isometric exercises would have to be performed at multiple joint angles for the same muscle group. This becomes time consuming and enervating for an athlete who may already be spending considerable time on other training modalities."

So what is the functional benefit for us with doing wall sits with the knees bent so far? Would it not make more sense to perform the exercise at the midpoint of your knee's normal range of motion as you run? I tried it and while it's definitely easier, I reached a point reasonably quickly where I was genuinely struggling to hold the position.

Just a question - they definitely seem like they do the job and the point at this stage is still to strengthen and brace the knee, so I suppose they'll get that done regardless.


Thanks guys. :)

You are wrong and right.

Isometric holds will not induce Hypertrophy, as you are only holding the same weight at an angle for a time. To cause hypertrophy you need to overload the muscle on a constant basis.
The rest of your statement is prety much correct.
If you want to use them to improve an aspect of your development then do holds for time at different angles and this will help. Part of the isometric hold advantge is activation of the muscle fibres that are dormant or less active than others. This over time allows you to have more muscle fibres avialable for use during activity.

If normal squats are getting too easy then you could - add weight - increase the range of motion - do 1 leg squats. There are many ways to increase the challange on your body. Do your squats then do an isometric hold during your recovery phase....this will ight the fire in your legs.

Train safe

#3 Mile27

    veryCoolRunner

  • Forum Member
  • PipPipPip
  • 621 posts
  • Joined: 03-October 11
  • Sex:Male
  • Location:Sydney

Posted 06 January 2012 - 08:58 AM

The functional benefit of wall squats for runners is very negligible.

The benefits gained in an exercise are specific to the range of movement, joint angle and position, speed of movement and the load used.

This is a universally accepted rule with strength and conditioning coaches and personal trainers and hopefully physiotherapists. So lets have a look  at wall sits and see how they match up in terms of what happens at the knee
                      
                                    
range of movement
Wall Sit  - none
Running -  around 20 degrees knee flexion during the stance phase

joint angle and position            
Wall Sit -  joint angle varies depending on how deep you sit, but if you sit at 20 degrees knee flexion then the exercise is very easy, body position is two legs together with back supported against a wall
Running - from 20 degrees to around 5-10 degrees at push off.Body position is standing on one leg other leg off the ground , body unsupported

Speed
Wall Sit - none as there is no movement
Running - foot hits the ground approx every .66 of a second

Load
Wall Sit - body weight plus any additional weight
Running - body weight plus the effects of gravity, ground reaction forces and momentum


Looking at the above it is hard to argue that wall sits will have any benefit for runners.

You feel the legs burn because the lactic acid builds up because the muscles arent contracting and relaxing which helps remove the lactate. How much you feel your muscles work is completely irrelevant to whether an exercise will be good for running.

They will strengthen and brace the knee when you are in a squat position with your back supported but when you land on your foot when you run and your foot begins to pronate, your knee begins to rotate inwards and go through abduction as your hip internally rotates, flexes and adducts it wont have any idea what to do since it has never been trained in that position.

The other point to consider is that runners knee is rarely CAUSED by weak quads, you may have weak quads but they usually arent the cause of the problem, usually the feet and or the hips are the problem. Only by addressing the body as a whole and training it to work together rather than isolating a particular muscle group can proper biomechanics be restored.

For more info and some suggestions of what is a far better alternative have a look at the following blogs


http://www.mile27.co...runners-part-1/

http://www.mile27.co...runners-part-2/

http://www.mile27.co...od-for-runners/