The purpose of the study was to determine the acute responses to a jump squat protocol designed to induce postactivation potentiation on sprint running performance in experienced track and field athletes and soccer players. Twenty-five regional level athletes (12 track and field: ∼17 years; ∼177 cm; ∼73 kg and 13 soccer: ∼18 years; ∼175 cm; ∼72 kg) performed 2 test sessions assessing 40-m sprint running performance in a balanced, crossover design. Dual-beam light timing gates measured 0-20 and 20-40 m sprint times before and after either 9 minutes of sitting (control) or 2 sets of 6 repetition half-squat jump with the load eliciting maximum power (experimental) conditions. Sprint performance was significantly enhanced over both 0-20 m (3.09 ± 0.07 to 3.04 ± 0.08 seconds; Δ ∼1.5%; p ≤ 0.05) and 20-40 m (2.42 ± 0.09 to 2.39 ± 0.09 seconds; Δ ∼1%; p ≤ 0.05) in track and field athletes only. Also, the magnitude of enhanced sprint performance was related to baseline 0-20 m sprint performance (r = 0.44; p = 0.028; n = 25). It seems that using loaded half-squat jumps to enhance sprint performance could be used in training of high-level young athletes.

This study investigated the effects of instantaneous performance feedback during the jumpsquat exercise over a 6-week training period. Twenty-five strength-trained athletes were randomly divided into an instant feedback (n = 13, half-squat 3-RM/body weight = 2.38 ± 0.19) or a non-feedback (n = 12, half-squat 3-RM/body weight = 2.03 ± 0.44) group. Both groups performed the same training program (3×week), consisting of 4 sets of 8 repetitions (weeks 1-3) and 8 sets of 4 repetitions (weeks 4-6) using a barbell with a load that maximized the average concentric power output (Pmax) of each athlete. Subjects in the instant feedback group were given real-time data after each repetition. Pre-, mid-, and post-training testing consisted of maximum 20m, 30m and 50m running speed, 3-RM back half-squat load, Pmax and the load that maximized average concentric power output (Pmax load), countermovement (CMJ) and squat jump (SJ) height. Results revealed that the feedback group significantly improved all selected tests versus non-feedback (time×group interaction, p<0.01). Significant improvements post-training for 20m, 30m, 50m, 3-RM load, Pmax load, CMJ and SJ were observed in the feedback group only (p<0.01). Training without instant feedback did not lead to significant performance improvements, this group actually demonstrated significant decreases in SJ and Pmax (W) and Pmax load (p<0.05). The results of this study indicate that the use of instant feedback during jump-squat training in athletes was beneficial for improving multiple performance tasks over 6-weeks of training. Instant feedback is an important element of power training to maximize adaptations when training strength-trained athletes.

The aim two groups time parallel 6-week experiment was to compare selected types of plyometric training. One group trained with gradation of external weight loading in eccentric phase (EXP1) and the second group increased drop height (EXP2) during drop jump training. We compared their effects on changes in selected strength abilities. We assessed the level of countermovement vertical jump height (CMJ), standing vertical jump height (SJ) and average force gradient in squat exercises with the knee joint in 90 ° by maximal isometric contraction at intervals of 0-50 ms (RFD50) and 0-200 ms (RFD200). The results showed that in CMJ EXP1 had improved by 1.01 cm (3.5%) (p<0.01). EXP2 improved by an average of 1.78 cm (5.5 %) (p<0.05). SJ in EXP1 average improved by 0.94 cm (3.5 %) (p = n.s.) in EXP2 by 1.91 cm (6.6 %) (p<0.05). In RDF50 the average increase observed after a period of training in EXP1 1.03 N.ms-1 (26.08 %) (p = n.s.) and EXP2 0.57 N.ms-1 (16.39 %) (p<0.05). In the EXP1 RFD200 the average increase was 2.51 N.ms-1 after a period of training (20.91 %) (p<0.01), while on average EXP2 improved by 1.05 N.ms-1 (10.04 %) (p = n.s.). Based on these results we recommend to improving of vertical jump height with a countermovement and force gradient in longer intervals (200 ms) to apply the external weight in the form of small dumbbells in eccentric phase of drop jump training. To standing jump height development and shorter time intervals of force gradient (50 ms) is recommended to use a gradual increase in height of drop in plyometric training.

Objektivizácia diagnostiky silovo-rýchlostných schopností je téma vysoko aktuálna. Väčšina štúdií bola doposiaľ zameraná na aktivitu svalových skupín, pomocou elektromyografie, v tlaku v ľahu na lavičke (benčprese) pri rôznych spôsoboch vykonania. Hlavným cieľom výskumu bolo porovnanie vybraných parametrov sily pri rôznych šírkach úchopu v tlaku v ľahu na vodorovnej lavičke. Hodnotili sme najvyšší priemerný výkon v celej a v akceleračnej časti koncentrickej fázy pohybu v stupňovanej diagnostickej sérii.Výsledky potvrdili hypotézy, pretože najvyšší priemerný výkon vo wattoch v celej koncentrickej fáze pohybu bol dosiahnutý úzkym úchopom s protipohybom 509,9±87,2 W v porovnaní s úchopom širokým 477,06±86,7 W (p<0,01). V akceleračnej časti koncentrickej fázy pohybu bol najvyšší priemerný výkon dosiahnutý úzkym úchopom s protipohybom 692,9±137,8 W. Širokým úchopom bol dosiahnutý najvyšší výkon 652,2±122,5 W (p<0,05). Odporúčame využívať úzky úchop v benčprese ako špeciálny prostriedok rozvoja silových schopností. Hlavne v športoch, ktorých biomechanická štruktúra pohybu je podobná ako napr. boby, hádzaná,karate, box a iné.

Cieľom práce bolo prispieť k objasneniu štruktúry limitujúcich faktorov športového výkonu v karate, z ktorých sme vybrali disjunktívne reakčno-rýchlostné schopnosti dolných končatín na optické podnety a rýchlosť úderu seiken čoku cuki z hľadiska hierarchického usporiadania vybraných motorických faktorov prostredníctvom kvantifikovaného matematického modelu. Namerané hodnoty sme spracovali a párovou korelačnou analýzou sme zistili mieru závislosti medzi jednotlivými premennými. Pomocou regresnej a parciálnej korelačnej analýzy sme zostavili empirický model štruktúry vybraných motorických faktorov limitujúcich výkon v karate. K nám zvoleným závislým premenným boli do druhej faktorovej úrovne na základe významných koeficientov mnohonásobnej determinácie zaradené motorické faktory: skok do diaľky z miesta, beh na 400m, hod plnou loptou a ľah sed. Do tretej faktorovej úrovne sme na základe štrukturálnej analýzy zaradili: beh na 50m, počet kľukov za 10s, beh zo zmenami smeru 10x5m, zhyby a výdrž v zhybe, prepočet VO2max.