The peculiarities of high-speed qualification of 11-16 years old tennis players

Introduction Modern tendencies of development of world tennis are caused by universalization of the game characterized by necessity in rational combination of active game on a baseline with attacking actions at the net, and also increase of accuracy and force of shots, increase of game rate. In turn, such features of game make considerable demands to high-speed abilities of tennis players.

Well-known that speed is shown in elementary and complex forms. To elementary it is accepted to reckon: speed of simple and complex reaction; speed of single movement (at small external resistance) and frequency (rate) of movements.

To complex forms: starting "acceleration", performance of integral actions (run, swimming, etc.) Research purpose Reveal the peculiarities of high-speed qualification of 11-16 years old tennis players Research problems
1) Determine the peculiarities of movements of qualified adult and young tennis players at the official competitions.
2) Determine the rates of high-speed abilities of 11-16 years old tennis players.
- simple and complex reaction time during global work from different start positions
- single movement time of left and right leg
- acceleration time from different start positions

Research methods
1) Analysis of literary sources.
2) Pedagogical testing with special panel, allowing to estimate:
- quickness of simple and complex reaction;
- single movement time of left and right leg;
- acceleration time from different start positions;
- height of the jump by flight time from different start positions;
3) Methods of mathematic statistics.
1. Analysis of literary sources.
The analysis of the researches spent in Russia and abroad has shown that to perform one shot the tennis player runs pieces up to 5 m. On the average men run for 95,7 %, juniors on "a fast" surface 86,5 % and on "a slow" surface – 83,0 % of all run pieces. Share of movements from 5 to 10 m in men‘s matches is 3,2 %, in junior‘s matches on "a fast" covering - 13,7 % and on "a slow" covering – 15,5 %, the other part – movements more than 10 m Table 1.

Tennis players for movements start from 3 various positions: run forward and backwards from «ready» position, run to the right pushing away with the left leg, and run to the left pushing away with the right leg.

Leading tennis players of the world and leading juniors during a match, both on "fast", and on «a slow covering» more often move in 4 directions: to the left – in 17,3 % of cases, to the right in 14,8 % of cases, forward in 54,3 % of cases and backwards in 13,5 % of cases [A.Skorodumova]. While on "a slow" covering – in 34,2 % of cases to the left, in 36,3 % of cases to the right, in 19,8 % of cases forward and in 10,6 % of cases backwards Pic. 2. From the presented Pic. 2 it is visible that on "a fast" covering it is necessary to do the most part of movements forward, however on "slow" - to the parties. Therefore, tennis players have often to start from various positions and push away with different leg.

For comparison tennis players of 13-14 years on "a slow" surface move to the left in 21 % of cases, to the right in 28 % of cases, forward on the left in 14 % and backwards to the left in 13 % of cases [O. Kuznetsova]. However, on "fast" – this ratio changes a little Pic.3.

2. Research organization.
Research was held on the basis of Tennis center RSUPCST. 52 tennis players have taken part in research: 24 persons of 11-12 years, 17 persons – 13-14 years and 11 persons – 15-16 years old, including members of youth national teams on the listed age groups. Testing consisted of 10 tests of high-speed and speed-power character with 3 attempts in each, during which speed of reaction and time of tasks performance were measured:
1) run on 5 m from «ready» position;
2) run on 5 m from position «an exit from shot on the left in the closed stand», i.e. standing the right side in relation to movement and making the start with the left leg;
3) run from position «an exit from shot on the right in the closed stand», i.e. standing the left side in relation to movement and making the start with the right leg.
4) run from «ready» position with start by the left or right leg depending on the type of signal;
5) run or a jump upwards pushing away both legs from «ready» position depending on the type of signal.
6) single movement by the left leg, while standing;
7) single movement by the right leg, while standing;
8) jump upwards pushing away both legs from «ready» position;
9) jump upwards pushing away by the left leg;
10) jump upwards pushing away by the right leg;
3. Methods of mathematical statistics
Mathematic-statistical processing of results of the pedagogical testing, conducted on the personal computer with use of programs StatSoft® STATISTICA 6.0 and Microsoft® Excel 2003, included calculation of descriptive indicators (mean, standard deviations), values of criteria (t-criterion of Uilkokson) and significance values. An error of a photo starting and a photo finishing devices 0,01 sec, the software 0,02 seconds.

Results
1. During testing it is determined that the task - run from «ready» position with pushing away by the left or right leg depending on the type of signal has appeared impracticable for anybody from tennis players of 11-16 years.
2. Authentic differences between time indicators in each age group are determined: 11-12, 13-14 and 15-16 years:
- Overcoming 5 meter pieces depending on a start position,
- Flight in high jumps depending on a start position,
- Time of performance of single movement by left and right leg,
- Simple reaction at run depending on a start position,
- Simple reaction at high jumps pushing away by left and right leg,
- Time of simple reaction at performance of single movement by a left and right leg,
- Simple reaction in run on 5 meters from «ready» position and at high jumps pushing away by two legs.
Results are presented in Table 4.
3. Start performance at run on 5 m from «ready» position occurs at all age groups of tennis players with technical breaches which lead to increase in time spent for overcoming of a piece.
4. Average-group time indicators of movements and reaction of 11-16 years old tennis players are determined. Table 5.

Conclusions
Results of testing testify the necessity for working out a special method which will allow to level differences between the left and right leg on indicators of high-speed and speed-power qualification of 11-16 years old tennis players and have a big practical value and the importance for construction of effective process of training and productivity increase in competitive activity.

A. Skorodumova, I. Baranov