Translations

Characteristics of the Movement of the Athlete/ Barbell System for Athletes of Different Sex

Characteristics of the Movement of the Athlete/ Barbell System for Athletes of Different Sex

Valentin Oleshko, Phd

Olimp 1-2:30-33:2010

Translated by Andrew Charniga, Jr.

Sportivny Press©

2010

The level of speed  strength development, for the most part, defines the weightlifter’s ability to achieve high results in the competition exercises. Therefore, the sportsman’s skill to display maximum speed in a brief time is as important as the realization of the athlete’s strength potential for lifting a barbell {3,9,13}.

 

An analysis of the literature shows contradictory data on the vertical speed of the barbell during the execution of the competition exercises. Some authors ({1,5,7,14} believe the higher the vertical speed, the better. Other authors {3, 917} believe the speed should be optimum and be commensurate with the task confronting the sportsman.

 

Another group {4,6,11,15} believe, and not without substantiation, that rational technique is characterized by a low barbell speed resulting from the final acceleration in the snatch and the clean;  it is this speed which permits the lifter to raise a maximum weight.

 

It has been established as well that the vertical speed increases with the rise in the athlete’s height and his weight class.

 

Consequently, in order to eliminate these contradictions we have investigated the barbell speed in the snatch and the clean for sportsmen of different gender and weight class groups, from the instant of barbell separation up to the instant the athlete/barbell system achieves maximum speed. Furthermore, we endeavored to compare the characteristics we obtained with those of other authors who have studied a similar aspect of weightlifting.

 

Our task was to study the speed characteristics of the movement of the athlete/barbell system for highly qualified weightlifters of different gender, height and weight.

 

We used the Weightlifting Analyzer 3.0 (Germany) to obtain computerized video data of the snatch and the clean and jerk. This enabled us to obtain data of the shifting of the center of mass (CM) of the athlete/barbell system. The data obtained was employed for calculations at three points: V1 – at the instant of the first maximum knee extension (at the end of the preliminary acceleration phase), V2 – the instant the sportsman applies maximum force (in the final acceleration), and Vmax – when the barbell reaches maximum speed. The barbell’s movement in phases was determined according to the published accepted phasic structure of the movements {8,9}. We also calculated speed  strength power (SSP) of the lifts according to Bartonietz’s formula {17}:

P = m x g x Vmax,

Where, m – mass of the barbell, g – acceleration of free fall (g = 9.81 m/s²), Vmax – the maximum vertical speed of the barbell.

 

The data was obtained from 240 of the world’s strongest weightlifters. We analyzed 300 lifts of male and 174 lifts of female lifters. In order to compare the speed characteristics of weightlifters of different height, we divided the athletes into weight class groups: men  56 and 62 kg; 69 and 77 kg; 85 and 94 kg; 105 kg; +105 kg; women  48 and 53 kg; 58 and 63; 69 and 75 and +75 kg.

 

The results are presented in tables 1&2. The data in the tables is of the vertical speed of the center of mass (CM) of the athlete/barbell system in the snatch and the clean for weightlifters of different sex and weight class group.

 

                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 
                 

1 – Preliminary acceleration phase; 2 – Final acceleration phase;

*MS – maximum speed; **SSP – speed – strength power

 

Analysis of the speed characteristics of the highly qualified weightlifter shows that the vertical speed of movement has a tendency to rise with the increase in weight category in both the preliminary acceleration (by 20%) and the final acceleration (by 21.9%). The lifters in the 85, 94 and 105 kg classes have the highest speed of movement in the snatch. The barbell’s speed in the preliminary acceleration comprises 75% of the maximum and 84% of maximum in the final acceleration. The speed  strength power indicator also rises by 36.6% with the increasing weight of the barbell.  

 

Table 2. Vertical speed of barbell in the separate phases of the clean.

Wt cl.        X        S        X        S        X        S        X        S

Males        PAP¹        PAP        FAP²        FAP        MS*        MS        SSP**        SSP

56,62 (n= 12)        1.17        0.11        1.28        0.11        1.43        0.13        1870        296

69,77 (n= 28)         1.22        0.17        1.21        0.17        1.35        0.19        2260        289

85,94 (n = 54)        1.17        0.21        1.22        0.19        1.38        0.22        2623        397

105 (n = 28)         1.20        0.22        1.20        0.17        1.35        0.16        2794        427

+105 (n = 28)         1.26        0.16        1.31        0.19        1.54        0.21        3483        364

x (n = 150)        1.21        0.17        1.24        0.16        1.41        0.18        2606        354

Females                                                                

48,53 (n = 9)        1.14        0.30        1.39        0.50        1.61        0.10        1676        70

58,63 (n = 21)        1.10        0.13        1.23        0.20        1.47        0.22        1639        254

69,75 (n = 36)        1.19        0.22        1.22        0.16        1.47        0.23        1708        204

+75 (n = 21)        1.31        0.18        1.35        0.18        1.56        0.18        2153        246

X (n = 87)         1.18        0.20        1.30        0.26        1.52        0.18        1794        193

1 – Preliminary acceleration phase; 2 – Final acceleration phase;

*MS – maximum speed; **SSP – speed – strength power

 

 

Analysis of the high class female lifters’ speed showed that the barbell’s vertical speed in the snatch rises with increasing weight class group, especially in the preliminary acceleration phase (by 26.9%).

 

In the final acceleration phase the light weights (58 and 63 kg) and heavy weight class (+75 kg) have the highest vertical speeds. These weight classes also have the highest maximum vertical speeds. The vertical speed of movement in the preliminary acceleration comprises 65% (10% lower than for men) of the maximum speed; the speed in the final acceleration comprises 84% of the maximum speed. The speed strength power indicator of the females increases with the rising weight class group by 32.2% based on the increasing weight of the barbell.

 

If you compare the vertical speed of the athlete/barbell system between males and females, then you will find that male weightlifters start with a higher speed (11.9%, p<0.05) than females; however, the speeds in the final acceleration phase between the sexes are approximately equivalent (the difference is not reliable). The same tendency is observed with the maximum speed.

 

A comparison of the speed  strength power indicator showed that it is 39% higher for males than females, principally because the males lift a larger weight.

 

Analysis of the barbell speed in the clean showed that there was an insignificant difference between the weight class groups for the males, but the +105 kg athletes had the highest speeds in both the preliminary acceleration and the final acceleration phase. The speed strength power indicator increases with the rising weight class by 35.6% principally because of the increasing weight of the barbell.

 

Nevertheless, the vertical speed of the barbell in the preliminary acceleration comprises 85.8% of the maximum speed for all weightlifters (10.8% lower than in the snatch) and 87.9% of the maximum speed in the final acceleration (which is 17.3% lower than in the snatch). The maximum speed of movement is 46.3% slower than in the snatch.

 

The vertical speed of the barbell in the clean does not increase significantly with the rise in weight class for the highly qualified female lifter.  For instance, the largest speed in the preliminary and final accelerations was recorded in the +75 kg class; but the maximum speed was recorded in the light (48 and 53 kg) and +75 kg classes.

 

The vertical speed in the preliminary acceleration comprises 77% of the maximum speed for females and 85.5% in the final acceleration phase. The maximum barbell speed in this exercise is 16.1% lower than in the snatch for the female lifter.

 

The speed strength power indicator of the female lifter increases along with the rise in weight class by 23.9% first and foremost because of the heavier barbell.

 

A comparative analysis of the barbell speeds between males and females in the clean showed that the male lifters accelerate the barbell with a larger speed in the preliminary acceleration phase (by 2.5% p>0.05); whereas, the females have larger maximum and final acceleration speeds (by 7.3 and 4.8%) than the males (p>0.05).

 

The speed  strength power indicator is 31.2% higher for the male lifters because they lift significantly bigger weights.

 

It is also of interest to compare the speed strength power indicator between the two exercises (table 3). We established that for the majority of the weight classes of both males and females (except +105 kg; 48, 53 and +75kg) speed  strength power is greater in the snatch than in the clean. However, logic would dictate that the power connected with lifting a barbell in the snatch is less because the weights are smaller in this exercise.

 

We decided to see if this is true in practice. In all weight classes the vertical speed of the center of mass of the system (CMS) was 21% smaller for males and 16% less for females.

 

If you analyze the difference in speed between the weight categories, you will find that the largest difference for males occurs in the middle weight classes (from 69 – 105 kg) and for females in the 58, 63 and +75 kg classes.

 

Table 3.

Wt cl.        Sn        Clean        Diff%        P        Sn        Clean        Diff%        P

Males        MS*        MS                        SSP**        SSP                

56,62 (n= 12)        1.77        1.43        -20        <0.05        2229        1870        -16.2        <0.05

69,77 (n= 28)         1.75        1.35        -23        <0.05        2529        2260        -10.7        <0.05

85,94 (n = 54)        1.82        1.38        -25        <0.05        2909        2623        -9.9        <0.05

105 (n = 28)         1.79        1.35        -25        <0.05        3071        2794        -9.1        <0.05

+105 (n = 28)         1.85        1.54        -17        <0.05        3456        3483        +0.7        –

x (n = 150)        1.79        1.41        -22        <0.05        2838        2606        -7.7        <0.05

Females                                                                

48,53 (n = 9)        1.76        1.61        -9        <0.05        1417        1676        +15.5        <0.05

58,63 (n = 21)        1.87        1.47        -22        <0.05        1674        1639        -2.4        –

69,75 (n = 36)        1.78        1.47        -11        <0.05        1758        1708        -2.9        <0.05

+75 (n = 21)        1.86        1.56        -17        <0.05        2087        2153        +3.1        <0.05

X (n = 87)         1.81        1.52        -16        <0.05        1734        1794        +3.4        <0.05

* MS – maximum speed

**SSP – speed – strength power

 

P.A. Poletayev {9, 10} obtained similar data of barbell speed variations during the snatch, depending on the weight of the barbell which is in full agreement with ours.

 

Consequently, we can conclude that the increasing weight of the barbell diminishes the maximum vertical speed and likewise the speed strength power indicator of sportsmen performing the clean.  

 

Conclusions.

 

1. Analysis of the special literature has shown that up until the present time there are varying opinions concerning the variations in barbell speed for the snatch and the clean for weightlifters of different sex and weight class group.  

 

2. We studied three of the most informative characteristics of the movement of the center of mass of the athlete barbell system (CMS): a) the vertical speed at the instant of the first maximum knee extension (VI); b) at the instant the sportsman generates maximum force (V2) in the final acceleration phase; c) at the instant of maximum barbell speed (Vmax).

 

The speed of the sportsman/barbell system increased for all athletes with the rise in bodyweight category during the preliminary acceleration phase of the snatch.  The maximum speed in the final acceleration of the snatch and the clean do not have a clearly established dependence which varies with the rise in weight class group for both males and females.

 

4. A comparative analysis of the vertical speed of the barbell in the clean between males and females revealed the same tendency as in the snatch: the starting speed of the females was less than the males, but in the final acceleration and the maximum speed it is larger for females.

 

5. The speed strength power indicator is higher in the snatch than in the clean except for the 48, 53 and +75 kg female categories and the +105 kg classes for men.

 

6. The speed characteristics of snatch and clean technique depend on the weight of the barbell, the sportsman’s qualification, weight class and gender.

 

7. The speed strength power characteristics of the movement of the athlete/barbell system obtained in this study can used for control of the weightlifter’s technique.        

   

 

 

 

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