Sunday, July 28, 2013

Wall Sit research

James Steele was good enough to point this out to me.

In the basic Hillfit routine the wall sit is a fundamental exercise.  This is an isometric squat held for time with your back supported by a wall.  I included the wall sit for a few reasons:

  • you do not need any equipment
  • it is scaleable - if you are weaker, hold an easier position for example do not adopt a 90 degree knee position, don't bend your legs as far
  • it is low skill - you don't need to learn a complex move.  Squats are actually pretty complex to perform properly.  I think a good squat pattern is important for health and mobility.
  • it is safe - it keeps you in safe positions for your structure and muscles. (Bill DeSimone calls it a congruent movement - you use your muscles in a way that they are strongest where the movement is hardest)
I also find it an effective move for the thighs and hips in terms of producing strength.  Holding a 2 minute wall sit takes some strength.  I've talked about the exercise on this blog before by the way.

Anyway, James pointed out this paper, just published.

The isometric wall squat could be utilised in home-based training aimed at reducing resting blood pressure, but first its suitability must be established. The aim of this study was to determine a method of adjusting wall squat intensity and explore the cardiovascular responses. Twenty-three participants performed one 2 minute wall squat on 15 separate occasions. During the first ten visits, ten different knee joint angles were randomly completed from 135° to 90° in 5° increments; five random angles were repeated in subsequent visits. Heart rate and blood pressure (systolic, diastolic and mean arterial pressure) were measured. The heart rate and blood pressure parameters produced significant inverse relationships with joint angle (r at least –0.80; P < 0.05), demonstrating that wall squat intensity can be adjusted by manipulating knee joint angle. Furthermore, the wall squat elicited similar cardiovascular responses to other isometric exercise modes that have reduced resting blood pressure (135° heart rate: 76 ± 10 beats ∙ min−1; systolic: 134 ± 14 mmHg; diastolic: 76 ± 6 mmHg and 90° heart rate: 119 ± 20 beats ∙ min−1; systolic: 196 ± 18 mmHg; diastolic: 112 ± 13 mmHg). The wall squat may have a useful role to play in isometric training aimed at reducing resting blood pressure.

Interesting to see this benefit of the exercise - reducing blood pressure.  Exercise is often promoted as a way of controlling blood pressure, but people usually take that as "cardio", thinking strength training will raise blood pressure.  Here the wall sit is shown to be able to benefit blood pressure.

Another nice point in the abstract (I've not read the whole paper) is the observation that  

wall squat intensity can be adjusted by manipulating knee joint angle. 

That is what I mean by it being a scaleable move.


SportsGuy said...

Wall sits need not be purely isometric. After I go 60 seconds isometrically I flex up and down the wall until failure.

The actual distance covered up the wall is tiny. Maybe an inch or so.

Chris said...

On the topic of isometrics and reducing blood pressure, "Evidence for an effective physical method for treating hypertension, by brief, maximal, extensive isometric exercise has been published in the Journal of the American Geriatrics Society (December 1971). It was demonstrated that blood pressure was reduced in four to eight weeks after the initiation of a regimen of isometric exercises."

The author, Broino Kiveloff, MD, summarized the regimen in a 1983 Prevention magazine article:

• Stand in a relaxed position, arms hanging loose. Don't clench your fists or bend your elbows or joints.
• Tense all your muscles at the same time as tightly as possible, while breathing normally and counting aloud to six. You might try tensing each muscle group separately -- legs, arms chest, abdomen, face -- and then try tensing them all at once. When you do, you should feel an immediate surge of warmth all over your body.
• Relax and rest for a few seconds.
• Repeat the exercise twice more.
• Do this three times a day (try morning, noon and night).
And that's all there is to it.

Dr. Kiveloff reportedly practiced this exercise himself and died at age 91 in 1994.

Robert Palmer said...


Your discussion about the benefits of wall sits prompted me to tinker with the exercise and I came up with the "dynamic wall sit." It'd be best if I could post a video of it, but here's how it works: put a Swiss/stability ball between your back and the wall, get into the normal 90-degree position of an isometric wall sit, and slowly stand up and squat down, never going too high or too low so as to maintain constant tension throughout the movement. You can increase the load by holding a dumbbell at your chest in a goblet hold, if necessary. I think it adds the benefit of being able to move through a larger range of motion without sacrificing form.

And if that description didn't make much sense, I'll have to get my act together and post a video of me doing it.