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The Start Position
There are certain sports where the duration of the event itself is shorter than its set up time. Inclusive in these short duration sports is Olympic Weighlifting. This article will cover the start position as it applies to the weightlifting biathalon: the snatch and the clean motions taken from the floor.
BASIC TERMINOLOGY
Before we cover in greater detail the process of establishing a proper start, we will first cover some basic terms as they pertain to weightlifting positions.
Foundation. Much like the starting blocks are to a sprinter’s start , the starting position is the foundation of weightlifting. In engineering terms, foundation is defined as the lowest load-bearing part of the structure, usually below the ground. In weightlifting, the lowest load-bearing position is the starting position where the feet make contact with the competition platform. As the foundation of the lift, the start position has to be extremely supportive, but consistent and controlled. This is the position where the performer will harness (summate) all their positional, mechanical, and muscular forces, to separate the apparatus from the supporting surface.
Center of Gravity (COG). The point at which the body is perfectly balanced. ls usually situated 2-3 inches below the navel. Interesting is the fact that the width of the female pelvis contributes to the lower center of gravity of the female lifter as compared to males.
Line of Gravity (LOG). The vertical projection upwards and downwards from the center of gravity. Both the apparatus and the performer have a center of gravity and a line of gravity projecting for our purposes downward.
Figure 1: Diagram of COG/LOG in a standing position and start position (click to enlarge)
ADDRESSING THE BAR: ESTABLISHING YOUR START POSITION
A stationary bar lies before you. As a lifter, in order to maximize your ability to lift the weight, a relationship has to be developed between you and the bar. Since the bar is stationary, addressing the bar means the performer needs to approach it and position him or herself to it as close as possible. The start position in weightlifting involves the following preparatory phases:
1. Approaching the stationary bar and placing the the feet under the bar and attaching the hands/upper extremities to the bar.
2. Setting the positions of the body segments relative to one another to optimize body mechanics.
3. Setting the muscles most involved to produce the potential energy prior to lifting the bar from the ground.
4. The summation of all the above to break the inertia of the stationary bar and separate the apparatus from the ground.
Therefore, our working definition of the start position is as follows:
The summation of addressing the bar, positioning body segments, and presetting the muscles most involved to break the inertia of the stationary bar to separate the apparatus from the ground.
ESTABLISHING YOUR STANCE
BASE OF SUPPORT
In mechanical terms the anterior-posterior length of the performer’s lifting shoes and the width of the performers foot placement represents the area of the base of the lifter. This is referred to in biomechanics as the base of support (BOS).
Most instructional courses in weightlifting encourage the placement of the bar over the metatarsophalangeal (MTP) joints in the starting position. lt is important to remember that the placement of the bar over the MTP joints is not set in stone and can be adjusted at any time.
Figure 2: Top view of the base support (click to enlarge)
To establish a biomechanically efficient starting position not only should the apparatus be located within the base of support of the performer but the line of gravity of the apparatus needs to approximate the line of gravity of the performer.
Figure 3: Top view of the base support showing the performer/apparatus (click to enlarge)
Due to the leverage of the human condition there will always be a distance between the line of gravity of the apparatus and the line of gravity of the lifter.
TOEING-OUT
Toeing the feet outward accomplishes a few things:
1. lt allows the line of gravity of the bar to more closely approximate the line of gravity of lifter.
2. The toeing-out position anatomically engages the gluteal muscles more effectively.
3. The toeing-out position through force plate studies in the 1960's has shown a greater ground force production.
In the 1960's the Japanese lifters experimented with an extreme toed-out position that was anatomically favorable for them. This was called the Japanese frog leg style of lifting. The Japanese weightlifters were able to accomplish this more favorably due to the mechanics of their leverage system.
BASIC BODY SETUP: SETTING YOUR POSITIONS AND MUSCLES
The relationship of the angles of the body to the bar placement over the MTP joints has to be optimized. I have found that one of the best teaching methods to do this is as follows:
1. Place your feet under the bar so that the width of the feet approximates the width of the pelvis. The feet can be straight or slightly toed-out, depending on your comfort level. The feet should be spaced accordingly so that they are equidistant from the center of the bar.
2. Situate the feet so that the bar is approximately over the MTP joints.
3. Bend forward from the trunk and grip the bar with equidistant hand spacing from the center the bar.
4. While maintaining this forward position of the trunk, move the shins forward to touch the bar.
5. Lift up head and chest so that the back is straight or slightly arched in the lumbar spine.
It is very important in the start position to make sure that forces generated from the body will be maximized. The spacing of the feet and hands will contribute to maximizing these forces. lf one studies pictures of advanced lifters from head-on, one can see that the lifters place their feet under the bar with their foot placement equidistant from a mid-sagittal plane coursing through the body and center of the bar. The lifter also places their hands on the bar equidistant from a mid-sagittal plane coursing through the body in the center the bar.
Figure 4: Nadezhda Yevstyukhina at the 2011 European Championships (click to enlarge).
Note symmetry of position and the approximation of force vectors.
MUSCLES MOST INVOLVED
Figure 5: David Rigert Breaking the Bar from the Floor © Bruce Klemens
If one observes the start position from a side view one will be able to observe the muscles most involved in the start position. A picture of the great lifter David Rigert will provide the best reference for the muscles.
One will notice from this photo exertion of the muscles of the thighs, pelvis, low back, and especially the upper back in the trapezius area along to the upper extremities that will attach the apparatus to the lifter. As stated before, the greatest stress on the body in the starting position is where the bar/apparatus is connected to the lifter's body at the posterior thoracic spine/interscapular muscle area. In order to be successful as a lifter one has to develop this muscle group as much as or more than any other area of the body. Without it, one cannot maintain proper head and spinal alignment and transfer the force of the apparatus to the lower spine, pelvis, and lower extremities.
IN SUMMARY
Thus a combination of of addressing the bar properly, optimizing the body segment angles, and utilizing the muscles most involved will provide the lifter with the best chance of separating the bar from the platform in the starting position.
The start position is such an important aspect of the lift, we incorporate it into our training as its own separate exercise.
Copyright © 2011 Marc Chasnov
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