Dr. Hab., Professor A.N. Tambovskiy¹
PhD, Associate Professor T.A. Sidorenko^{1, 2}
PhD, Researcher A.V. Kalashnikov^1
1Moscow State Academy of Physical Education, Malakhovka, Moscow Region
²Ryazan State University named for S. Yesenin, Ryazan

Keywords: athlete, preparatory and pre-competition stages, recovery, running stride, biomechanical indicators, comparison.

Introduction.
The active use of recovery methods in the training process of athletes requires coaches to understand the impact of these methods on the capabilities (including technical ones) of athletes. This knowledge is particularly relevant during the preparatory and pre-competition stages.
Research aim: to compare the main biomechanical indicators of the running stride technique of long jump athletes after recovery interventions at these stages of the annual training cycle.

Methodology and research organization.
The research was conducted as part of a state assignment from the Ministry of Sports of the Russian Federation. The participants were 14 qualified long jump athletes (first category to candidate master of sports). The methods used included magnetic laser stimulation, electrostimulation, tensometry, biopotentiometry, high-speed video recording, generalization, and mathematical statistics.

Results and discussion.
Five informative biomechanical indicators of the running stride were identified:

g1 – indicator characterizing the maximum acceleration of the foot in the horizontal plane;

t2g – time indicator of the foot's forward movement;

t3v – time indicator of the foot's vertical movement;

t2v – transition of the foot's work from negative to positive values (practically the flight phase);

TG – integral time indicator characterizing the total work time of the ankle and practically the length of the running stride.

It was noted that the preparatory stage of the annual training cycle for long jumpers is aimed at developing their functional systems, building the body's functional reserve, and is not focused on refining the run-up technique. After a course of recovery interventions, the following values were recorded for the participants:

g1: 19.91 ± 2.66 m/s²;

t2g: 75.20 ± 11.04 ms;

t3v: 83.42 ± 13.18 ms;

t2v: 140.22 ± 12.10 ms;

TG: 344.14 ± 12.62 ms.

At the pre-competition stage, significant biomechanical indicators changed: the g1 indicator was replaced by t3g, characterizing the time of the foot's vertical movement. After recovery interventions, the following values were recorded:

g1: 24.24 ± 2.51 m/s²;

t2g: 68.29 ± 11.08 ms;

t3v: 60.53 ± 3.41 ms;

t2v: 131.82 ± 90.15 ms;

TG: 312.51 ± 12.36 ms.

Conclusions.
The biomechanical indicators of the running stride technique of long jumpers at the pre-competition stage showed significantly better values compared to the preparatory stage, provided that the athletes underwent a cycle of recovery interventions, including magnetic laser and electrostimulation effects on specific muscle groups.

References

1. Tambovsky, A. N., Furaev, A. N., Han, C., & Sidorenko, T. A. (2022). Izmeneniya biomekhanicheskikh pokazateley sportsmenov posle primeneniya vnetrenirovochnykh sredstv [Changes in biomechanical indicators of athletes after the use of non-training methods]. Uchenyye zapiski universiteta im. P.F. Lesgafta, 2(204), 394–398.
2. Tyupa, V. V., Arakelyan, E. E., & Primakov, Y. N. (1990). Biomekhanika bega (mekhanicheskaya rabota i energiya) [Biomechanics of running (mechanical work and energy)]. Moscow.