Simple Statics: think of Torque when lifting
Friday, July 4th, 2008I am very mechanically minded/inclined and being that I was a mechanical engineering major for 3 1/2 years, I have done a lot of math and physics as well…so pardon me for being a nerd in this blog haha, just some tips for you guys!!
The way I think and see things is different from most people. I see how forces are applied in situations in my head. I always visualize what certain motions or workouts will do to my muscles, and where the most emphasis lies….Since gravity is obvious and pulls in the same direction, most people do ok with that. But with cables, you can vary the direction of the pull on your muscles, so this is where i usually see people with the machines and their bodies set at the wrong angles…
This being said, I think people would get more out of their lifts if they put some thought into how they are pushing weight and the angles they use in different motions. Basically, one way to think about it is the hardest part of a lift is when the weight is pulling at a 90 degree angle to your arm, or whatever body part. Thats how torque works. If you push a wrench on a stubborn nut you want to push the wrench 90 degrees to it to exert the most torque. Also, the longer the lever arm, the more torque can be applied….T=(force)(lever arm length)
In a curl, the hardest point with a free bar is when your forearms are parallel to the floor (momentum aside…) Also, most people tend to get stuck on a bench press right about when their upper arms are parallel to the floor….all this is due to gravity being a vertical force.
So when I do concentration curls with a cable, i step to the side and back a bit from the pulley at the floor, (curling with my right arm, cable at the right, and i stay to the left of it) which puts more emphasis on the lower part of my bicep. Since the cable is pulling to the outside, away from the curl motion, and a little in front of me, instead of straight down, its harder on the outer and lower bicep, which is exactly where i want it…
If you are doing a lateral cable raise for your shoulder, dont have the cable set too high off the ground, or stand too far from the pulley. If you do that, as you raise your arm, your cable gets more and more inline with your arm, and reduces the force on your shoulder greatly. Think of it this way, will it be easier for you to hold a dumbel straight out to the side at 90 degrees or barely extended with your arm just off your hip? obviously it will be harder if youre standing because the force is at 90 degrees to your arm…
Another common problem i see is people doing cable flies on the the machines. People will set the arms too narrow or wide…If its too narrow, the cable will pull hard in the beginning, but then as it gets more inline with your arm, you will hardly feel anything as you get to where your hands are touching. If its too wide, then it will be way to easy in the beginning and hard in the middle. This is all fine if you actually realize that this is going on…cuz this can be used for weak point training. Also, if your arms are bent way too much in a fly, the lever arm is shortened, reducing torque and difficulty through the motion. So keep your arms only slightly bent in a fly, and you will also be able to squeeze all the way in more effectively at the finish as well…
well thats my little thought for today! hope I was not too confusing and that you actually got something out of my blog! happy lifting…






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