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Powerpushups

A rope and someplace to tie it down...
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Are pushups just getting too easy for your 'roid juiced arms?*** Try this:

Step 1: tie a 3 meter rope to your feet. Step 2: tie the other end of that rope to something solid, like a tree, about 30-40 centimeters off the ground. Step 3: get into a pushup position in line with the rope, so that the rope passes over your head and is in tension enough to keep your feet from touching the ground. Step 4: Commence doing pushups. As long as the rope is roughly horizontal, you are now supporting most of your weight of your body by your arms, as opposed to only part of your weight as with the usual pushup.

***I don't suffer from this condition.

RayfordSteele, Aug 10 2006

Hindu pushups video http://www.google.c...safe%3Doff%26sa%3DG
[normzone, Aug 10 2006]

[link]






       umm, bench press?
methinksnot, Aug 10 2006
  

       Actually, as a normal pushup is almost horizantal as well, this doesn't enhance the resistance at all. Much of your body weight is still resting on the rope.
jellydoughnut, Aug 10 2006
  

       Dang. I was expecting a bra with hydraulic cylinders.
ldischler, Aug 10 2006
  

       Oh, and I thought it was one of those ice cream things (called push-ups) that would have its own hydraulics, to push itself out of the container.
xandram, Aug 10 2006
  

       You either have to bend your legs, or the rope can't be horizontal. And if it is horizontal, yes, you are supporting your entire weight with your hands.
ldischler, Aug 10 2006
  

       That too. I assumed he meant "nearly" horizontal, but the 30-40 cm has me baffled. Maybe RS has stubby arms? My back is more on the order of 65- 70 cm above the floor when in a "pushed-up" position.   

       I await an illustration.
half, Aug 10 2006
  

       [link] to Hindu Pushup video - wow...
normzone, Aug 10 2006
  

       //And all of the force required of your muscles is perpendicular to the ground?// I don't see how either. I agree that you are supporting your full weight, but you are also providing the rope tension which means you are also pushing in the direction above your head. This should add up to a required force greater than your own weight applied at an angle somewhere between perpendicular and parallel to your body. Muscularly, this is an inclined bench press of more than your own weight.
Shz, Aug 10 2006
  

       [ldischler]; if the rope is horizontal, then your legs are still supporting a portion of the weight. You can tell by the fact that the rope would be taught that your legs are pulling on it. For a horizantal push up to bear the weight of your entire body, ther must be no rope; you must balance your body horizantally with only your hands in contact with anything. This is impossible, so try a hand stand push up.
jellydoughnut, Aug 10 2006
  

       [jelly], The rope is attached at 30-40 cm. It will angle up when you push up. The weight that 'hangs' from it only does so because your back / butt is holding the rope up. You still have to lift this (leg) weight with your arms.
Shz, Aug 10 2006
  

       I'd like to see a diagram. I don't see how it's possible for someone to support their entire weight when their entire body is parallel to the ground and at a right angle to their arms.
jellydoughnut, Aug 10 2006
  

       I think your arms will need to be at about 45 deg to your body. I'll try it this weekend. Despite the fact that I have always been vehemently opposed to the use of steroids and other performance enhancing substances, I can lift more than my own weight on an incline.
Shz, Aug 11 2006
  

       Great...I can lift one of my cats...
jellydoughnut, Aug 11 2006
  

       The initial idea was to try and find a way to 'balance' on your hands, with some assistance, so that the weight of your legs could be added. But I think jellydoughnut is right; at least some of your body weight is resting on the rope. However, I believe there is an overall increase in the force vector in the direction over your head, so it might have some benefit.   

       Concerning the 30-40 centimeters: I wanted to split the difference between halfway up, and halfway down. If the rope were higher, it would only be horizontal in the 'up' position.   

       There will only be as much tension in the rope as the opposing sum of horizontal force vectors will allow. As the only horizontal force vector the opposite direction will be at your wrists, your body will be in a compressive force, and therefore the maximum tension in the rope will be constrained by whatever force your hands can deal with at the friction surface, otherwise you're sliding.   

       Bench presses aren't easily transportable.   

       Hindu pushups don't look hard at all.
RayfordSteele, Aug 11 2006
  

       Eh? You're MFDing yourself? I understood your idea, and it seemed fine, perhaps in need of a little tweaking to keep the rope horizontal. But now I don't understand your last anno a whit. I can only assume that you've gone out and gotten stinking drunk. So mods, ignore him. He doesn't know what he's saying.
ldischler, Aug 11 2006
  

       Then maybe you'll make the diagram.
half, Aug 11 2006
  

       //Eh? You're MFDing yourself? //   

       I think that's quite respectable. I've done it before.   

       I just did a few (Hindu Push ups). I don't think they acheive what [R Steele] was thinking, but instead require the use of many other muscles than would normally be used in the standard push up.   

       Push ups w/ your feet on a bed might come close, though (definately more difficult than normal push ups).   

       ***I don't suffer from this condition either. (I'm still baby'ing my what should be a long ago healed broken collar bone)
Zimmy, Aug 11 2006
  

       I agree with the self-inflicted mfd; if your arms are supporting your entire weight, the rope is not supporting any; so why is the rope there?
angel, Aug 11 2006
  

       //why is the rope there?//
It's a simple matter of statics. Your arms are displaced from your center of gravity. This produces a torque which has to be resisted, or your body will begin to rotate, and your feet will strike the ground. A horizontal rope going over your head to attach to your feet (assuming you legs are bent up at the knees to get them above your center of gravity) provides the balancing torque.
(The force on your hands isn’t entirely vertical--it’s the vector sum of the vertical and horizontal forces. As this is greater than your weight, it’s truly a difficult push-up.)
ldischler, Aug 11 2006
  

       I gave it a try. Here's the problems I had:   

       - The horizontal force required was greater than I had anticipated, meaning my arms had to be at an angle closer to horizontal than vertical. At this angle my hands didn't have enough traction (on grass). Using an angle where my hands didn't slip was murder on the shoulders.
- The rope stretched, making hand positioning (distance from the tree) very difficult. There was almost no margin of error.
- Preventing the legs / body from swinging down is the idea here, but it was preventing them from swinging side-to-side that proved nearly impossible.
  

       Conclusions:
- It is possible to do as is, at the risk of damaging your shoulders. I could do it for a half-second before swinging sideways.
- It is not bad physics.
  

       What is needed:
- An adjustable 'T' bar to brace at the base of the tree and place your hands on so traction is not an issue. This allows for proper angling of the arms.
- Airplane cable or other minimally stretching tether.
- Two stakes in the ground to prevent side-to-side motion.
  

       Adding these things takes away some of the portability, of course, but I bunned it anyway. It's halfbaked and possible.
Shz, Aug 14 2006
  

       No video to link to, [Shz]? I bunned also, after reading that you were actually able to do it.
Zimmy, Aug 14 2006
  

       I was going to have my daughter take a picture in the up position, but felt I couldn't hold the position long enough for her to get a shot.
Shz, Aug 14 2006
  

       \\//Eh? You're MFDing yourself? //\\   

       //I think that's quite respectable. I've done it before.//   

       I always thought it was MFE for your own stuff.   

       On-topic: Just did a couple of hindu pushups, and those are pretty hard.
shapu, Aug 14 2006
  

       I ran through a free-body diagram sketch of this and it seems to work out. Need to make it more explanatory and presentable before I post it here, if I ever have time...   

       Also tried it the other day. Does work, although the noted side-to-side leg swinging is difficult to handle.
RayfordSteele, Aug 15 2006
  
      
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