To clean the heaviest possible weight with a mid-height squat, the barbell should be driven from the bottom, for example, the lower third, of the thighs. Not from the top of the thighs, and certainly not from the groin. Why?
Because your balls are there?
NO! First, it's all about the order in which the lifting muscles are activated: from strongest to weakest. As I hope I explained in the "Amendment to Theory" text, the strongest muscles when lifting near-maximal weights are the calves, although they don't actually contribute the most to accelerating the barbell; rather, the quadriceps which, while exerting significantly less force, are many times more massive, and therefore much more capable, exert their force over a much longer acceleration than the calves.
As can be seen in these photos of Kurentsov and Bashanovsky . . .
. . . Olympic lifting champions and experts in the low squat were lifting the barbell after they had come up on toes. I still believe "do you come up on toes while jerking" is a killer opening line, but let me repeat: those who are experts at cleaning with lowe squats (he means Fred here?), no, experts at cleaning with low squats simply rose up on their toes, but didn't yet engage the barbell. Only later, after they'd long since risen up on their toes did they finally engage the now-high barbell with their groins or upper thighs.
"Engage" here refers to giving the bar a brush, bump and/or boink with those parts of the body. Here's another take on the bump, by Tommy Kono in his ABCs of Lifting series . . . a great series worth checking out now and then:
A specialist in powerful pulls, and cleans with relatively high squats, does, of course, something entirely different. They "push" the bar precisely when this bump can be performed with maximum force, i.e., during the toe-raising phase. Thus, the enormous strength of the calves is largely devoted not only to the pull but also to the powerful forward thrust of the bar with this movement (produced, I repeat, by the calf muscles.)
I know that for some reason most people think that the higher the lift, the more beneficial it is for acceleration and for achieving maximum barbell speed. Why it's beneficial is unclear, but this majority of people forget one of the most fundamental rules of arithmetic: The sum remains unchanged when the order of terms is changed, a.k.a, the
Secondly, the low kick (we'll call this "kick" a bump from here on) has another important advantage over the high kick. The low thigh bump, while noticeably slower than the groin bump, is noticeably stronger, more powerful and more energetic.
But you can't really impart particularly high speed to the bar by using the bump. Only a kettlebell, dumbbell or swingbell can be swung between your legs along a very long trajectory reaching speeds of around 2 m/sec or more. You can't impart such high speed and energy to the bar with the meager bump used by weightlifters. And that's okay, because bumping isn't the primary acceleration tool for weightlifters anyway. It's good if the bump's contribution amounts to 15-25% of its total energy. Such a contribution is still quite valuable.
So, it's impossible to impart any particularly high speed to the bar by bumping/kicking it, no matter where it's applied. But, as I'll explain later, bumping at various body heights exerts varying force.
The least force can be applied to the bar by "jacking" it with the neck or head. And the greatest force can be applied to the bar by jacking it with the ankles. Unfortunately, the ankles of the lifter jacking the bar are almost always motionless; therefore, the ankles themselves can't impart much speed to the bar by horizontally pushing it.
In general, a weightlifter pushing a bar with his body can be likened to a vertical lever with a fixed end at the bottom and some significant mass at the top. The lifter's "bottom end" is "fixed" to the platform due to the enormous frictional force that occurs during the pull. At this moment the lifter's weight increases greatly as the force of his interaction with the support increases. This can be recorded with a strain-gauge platform. This weight during the pull is the sum of:
1) the force of gravity of the lifter's body,
2) the gravitational force of the bar,
3) the force with which the weightlifter vertically lifts and accelerates the bar against the action of its inertial force,
4) as well as the centripetal force, which is the lifter's reaction to the counteraction of the centrifugal force that arises as a result of the swing-like rotational movement of the horizontally lifted bar.
As is well known, frictional force is directly dependent on the coefficient between the rubbing surfaces and the force compressing the rubbing surfaces. And at the moment of lift-off, this force, compressing the platform and the lifter's shoes, is enormous.
So, during the "push up" (a horizontal, forward thrust of the body against the bar), the lifter's feet cannot move due to the huge frictional force that occurs between them and the platform. Therefore, the lifter, pushing the bar forward with his body can, I repeat, be likened to a vertical lever with a fixed end at the bottom and a significant mass at the top.
As is well known, and this is the "golden rule of mechanics," the force exerted by a lever on a material body is inversely proportional to the distance from the point of application to the force of the lever's point of rotation: the shorter this distance to the lever's point of rotation, the greater the force exerted by the lever on the material body.
So, the area of he body from the end of the lower third of the thigh to the middle of the thigh is optimal for accelerating the barbell being lifted for the following reasons:
On the one hand, by striking with this area of the legs, the bar can be given a considerably greater horizontal velocity . . .
On the other hand, striking with this area of the legs (which, as I recall, is closer to the lever-body's point of rotation than the groin) has significantly greater force than striking with the groin, which is located significantly further from the lever-body's point of rotation.
Enjoy Your Lifting!
20,000 or so pulps from the past:
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