BACKGROUND: The study aimed to assess the acute effects of overcoming isometric split squats on subsequent single-leg drop jump (DJ) performance and the contralateral effect in volleyball players, considering training status differences. METHODS: Ten male elite (ELI) and ten amateur (AMA) volleyball players took part in two experimental sessions in which they performed conditioning activity (CA) consisted of 3 sets of overcoming isometric 3-second split squats, differing in the limb used: dominant (DL) or non-dominant (ND-L). Single-leg DJ was performed before and at the 4th and 8th minute post-CA for both limbs. The best post-CA attempt in terms of jump height (JH) was analyzed. RESULTS: Results revealed a significant increase in jump height (JH) in the non-dominant limb (ND-L) from 13.7 ± 2.6 cm to 15.5 ± 2.7 cm after CA performed by the ND-L (p = 0.001; Hedge's g = 0.65). Similarly, the reactive strength index (RSI) of the ND-L improved from 0.40 ± 0.06 to 0.45 ± 0.08 (p = 0.008; g = 0.58). Additionally, contact time in the ND-L increased significantly from 342 ± 36 ms to 375 ± 42 ms after CA performed by the dominant limb (p = 0.001; g = 0.66). In the elite (ELI) group, JH significantly increased from 16.4 ± 2.4 cm to 18.3 ± 3.3 cm (p < 0.001; g = 0.79), while RSI in the dominant limb (DL) improved from 0.47 ± 0.06 to 0.53 ± 0.07 (p = 0.011; g = 0.68). CONCLUSIONS: Results suggest that the examined CA effectively induces the post-activation performance enhancement in DJ among elite volleyball players, with a predominantly local impact on the limb executing the CA. TRIAL REGISTRATION: NCT06459050 (Retrospectively registered).
- Publication type
- Journal Article MeSH
The main purpose of the study was to establish, whether future cardiorespiratory fitness might be predicted by the level of muscular fitness at baseline. In this 3-year follow-up study, we recruited 240 secondary school girls at the age of 15 y, who were followed until the age of 17 y. Muscular fitness included the following tests: (i) standing broad jump (cm), (ii) sit-ups in 60 s (#) and (iii) squats in 60 s (#). Cardiorespiratory fitness was split into aerobic endurance (the 800-m run test) and speed endurance (the 400-m run test). Better performances in the 800-m run and the 400-m run tests at follow-up were correlated with higher levels of standing broad jump, sit-ups and squats in 60 s measured at baseline. In regression models adjusted for fat mass and maturity offset, standing broad jump, sit-ups and squats in 60 s were positively associated with the 800-m run test, while only standing broad jump remained significantly and positively associated with the 400-m run test. These data suggest that interventions enhancing muscular fitness should be recommended, as the effects are likely to be associated with future cardiorespiratory fitness in adolescent girls.
- MeSH
- Exercise MeSH
- Cardiorespiratory Fitness * MeSH
- Humans MeSH
- Adolescent MeSH
- Follow-Up Studies MeSH
- Nutritional Status MeSH
- Physical Fitness MeSH
- Check Tag
- Humans MeSH
- Adolescent MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
The objective of this study was to compare (i) The effects of a flywheel and free-weight resistance training program; and (ii) The effects of performing lateral and frontal split squats as part of a flywheel-resistance training program on jumping performance, the 5-0-5 change of direction test time, and the one-repetition maximum (1RM) back squat in soccer players. Twenty-four male amateur soccer players participated in this study and were randomly and equally assigned to one of three different test groups: forward split-squat group (FSQ); lateral split-squat group (LSQ); and free-weight training group (TRAD). Athletes in the FSQ group performed a squat and a forward split squat on a flywheel device, while those in the LSQ group performed a squat and a lateral split squat (instead of a forward split squat) on a flywheel device. Each training lasted 4 weeks. The main finding was that all training groups, such as TRAD, FSQ, and LSQ, significantly improved broad jump length (p = 0.001; effect size [ES] = 0.36), 5-0-5 COD time with a turn on the dominant limb (p = 0.038; ES = 0.49), and 1RM back squat (p = 0.001; ES = 0.4). In turn, both flywheel-resistance training groups (FSQ and LSQ) significantly improved their counter-movement jump height (p = 0.001; ES = 0.8 and p = 0.002; ES = 0.58; respectively) with no effect in the TRAD (p = 0.676; ES = 0.07) training group. Both free-weight and flywheel-resistance training lasting 4 weeks performed in-season contributed to significant improvement in 1RM back squat, broad jump performance, and 5-0-5 change of direction testing time, while flywheel-resistance training might be superior in counter-movement jump height enhancement in soccer players. Moreover, the manner in which split squats were performed was not a factor influencing the obtained results.
- Publication type
- Journal Article MeSH
The goal of this study was to compare the effects of a bilateral conditioning activity consisting of back squats and drop jumps with a unilateral one consisting of split squats and depth jumps to lateral hop over sequentially performed countermovement jump (CMJ), modified t-agility test (MAT), and Achilles tendon stiffness. Twenty-six basketball players participated in this study and were randomly and equally assigned to one of two different test groups: bilateral (B - CA) or unilateral (U - CA) conditioning activity group. The B - CA group completed 2 sets of 4 repetitions of back squats at 80% of one-repetition maximum (1RM), then 10 drop jumps, while the U - CA group performed 2 sets of 2 repetitions of split squats on each leg at 80%1RM, followed by 5 depth jumps to lateral hop on each leg as conditioning activity (CA) complexes. After a warm-up and 5 min before the CA the baseline Achilles tendon stiffness, CMJ, and MAT time measurement were performed. In the 6th min after the CA, all tests were re-tested in the same order. The two-way repeated measures mixed ANOVAs revealed that both B - CA and U - CA failed to produce significant improvements in CMJ and MAT performance. In addition, a significant increase in Achilles stiffness was demonstrated with both protocols (a main effect of time: p = 0.017; effect size = 0.47; medium). This study revealed that combining back squats and drop jumps, as well as split squats and depth jumps to a lateral hop, had no effect on subsequent CMJ and MAT performance in basketball players. Based on these results, it can be assumed that combinations of exercises, even if they have similar movement patterns, may cause excessive fatigue, resulting in no PAPE effect.
- MeSH
- Achilles Tendon * MeSH
- Basketball * MeSH
- Exercise MeSH
- Humans MeSH
- Posture MeSH
- Athletic Performance * MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Randomized Controlled Trial MeSH
Introduction: Ice hockey is a power-speed sport played on ice. The surface specification is very different from a normal surface, so it is important to look for the most appropriate measurements and specific off-ice tests that would better define ice-hockey performance. Therefore, the main purpose of this research was to determine the relationship of rate of force development (RFD) in back squat with commonly used off-ice and on-ice tests. Methods: The research involved 15 junior ice-hockey players (181.8 ± 4.1 cm; 80.7 ± 8.8 kg; 18.4 ± 0.9 yrs) playing in the highest competition of Czech hockey. Players performed all tests in one day divided into 2 blocks - off-ice block (OFF) in the morning and on-ice block (ON) in the afternoon, respectively. The OFF contained 30 m sprint test with 15 m split (SP15; SP30), plyometric tests (broad jump - BJ; countermovement jump - CMJ), and a velocity squat protocol (VSP). Finally, in the ON was performed speed and coordination tests - 30 m forward skating with 15 m split (FW15 and FW30); 30 m backward skating with 15 m split (BW15 and BW30); Weave agility test (WAT); Transition test (TT) and Pro-agility test (PAT). Results: No significant results were found between RFD and coordination tests (TT, WAT, PAT) and CMJ. The significant correlations were found between RFD40kg and SP30 (r = -.865; p < .01) and BJ and RFD40kg, respectively (r =.649; p < .05). However, as the back squat loads increase, the correlation strength decreases between RFD and SP30 (r = -.677; p < .01 for RFD50kg and r = -.560; p < .05 for RFD60kg). Moreover, the strong degree of correlation were observed between RFD40kg and FW15 (r = -.699; p < .05) and also FW30 (r = -.705; p < 0.05). Conclusion: The results of the study show a significant relationship between the RFD and commonly used off-ice and on-ice tests.
This review aimed to summarize the reported effects of unilateral conditioning activity (CA) on unilateral performance, bilateral performance, and the contribution of activated body limb to bilateral performance. A systematic search on MEDLINE, SPORTDiscus, Scopus, and Google Scholar was conducted on February 2022. Twenty-three studies met the inclusion criteria. Throwing, jumping, swimming, change of direction, and isokinetic performance were used as outcome measures to assess the impact of unilateral CAs on inducing post-activation performance enhancement. Eleven studies examined the effectiveness of resistance exercises as a CA, seven investigated plyometric exercises, and five used isokinetic muscle actions as CAs. Notably, only three studies directly compared the effects of bilateral and unilateral CA, and no study reported possible changes in the contribution of each limb during bilateral exercises executed following unilateral CA. Split squats were the most often studied CA (7), and it was shown that multiple sets of high-loaded split squats (85% one-repetition maximum) executed as CA, improve vertical jumping and change of direction after 4 to 8 min of recovery. At the same time, multiple sets of alternate leg bounds performed with ~10% body weight or without any external load result in an improvement of sprint performance, 2 and 8 min later, with the effect being greater when loaded jumps are used. The unilateral CAs such as split squats, alternate leg bounds, and drop jumps can be effectively used to acutely improve a wide variety of athletic tasks, including jumping, sprinting, change of direction, and swimming performance.
- MeSH
- Exercise physiology MeSH
- Humans MeSH
- Plyometric Exercise * MeSH
- Posture MeSH
- Athletic Performance * physiology MeSH
- Exercise Therapy MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Systematic Review MeSH
The aims of this study were to determine the relationship between vertical jumping performance, linear speed, change of direction speed (CODs) time and the COD deficit (CODD) in adolescent basketball players and to analyze the CODD between faster and slower players based on linear speed performance. Thirty-eight male basketball players (age: 15.47 ± 0.51 years; body height: 185.19 ± 5.67 cm; body mass: 71.87 ± 7.29 kg) completed countermovement jumps (CMJ) with and without an arm swing, squat jumps (SJs), linear sprints at 20 m with split times at 5 and 10 m, the pro-agility test and the zig-zag tests. Furthermore, the CODD was calculated as the difference between the 20 m linear speed result and CODs time in both COD tests. Pearson and Spearman analyses were used to determine the correlations between power-speed-related variables and the CODD. Moreover, independent t-tests and Cohen's d effect size (ES) were used to analyze the differences between the faster and slower players in the CODD. Moderate to strong significant negative correlations were observed between the CODD in the pro-agility test and linear speed at 5 m, 10 m, and 20 m (r = -0.55 to -0.46), while moderate negative significant correlation was found between the zig-zag CODD and SJs (r = -0.37) as well as small positive significant correlation between the CODD in the zig-zag test and the eccentric utilization ratio (EUR) (r = 0.23). Additionally, faster basketball players displayed significantly higher CODD values performing the pro-agility test. In summary, these findings underline the complexity of COD performance and the importance of remodeling traditional training programs in basketball players.
- Publication type
- Journal Article MeSH
The forward walking lunge (WL) and split squat (SSq) are similar exercises that have differences in the eccentric phase, and both can be performed in the ipsilateral or contralateral carrying conditions. This study aimed to determine the effects of dumbbell-carrying position on the kinematics and electromyographic (EMG) amplitudes of the gluteus medius (Gmed), vastus medialis (VM), vastus lateralis (VL), and biceps femoris during WLs and SSqs. The resistance-trained (RT) and the non-resistance-trained (NT) groups (both n = 14) performed ipsilateral WLs, contralateral WLs, ipsilateral SSqs, and contralateral SSqs in a randomized order in a simulated training session. The EMG amplitude, expressed as a percentage of the maximal voluntary isometric contraction (%MVIC), and the kinematics, expressed as the range of motion (ROM) of the hip and knee, were measured during 5 repetition maximum for both legs. The repeated measure analyses of variance showed significant differences between the RT and NT groups. The NT group showed a smaller knee flexion ROM (p < 0.001, η = 0.36) during both types of WLs, whereas the RT group showed a higher eccentric Gmed amplitude (p < 0.001, η = 0.46) during all exercises and a higher eccentric VL amplitude (p < 0.001, η = 0.63) during contralateral WLs. Further differences were found between contralateral and ipsilateral WLs in both the RT (p < 0.001, η = 0.69) and NT groups (p < 0.001, η = 0.80), and contralateral WLs resulted in higher eccentric Gmed amplitudes. Contralateral WLs highly activated the Gmed (90% MVIC); therefore, this exercise can increase the Gmed maximal strength. The ipsilateral loading condition did not increase the Gmed or VM activity in the RT or NT group.
- MeSH
- Biomechanical Phenomena physiology MeSH
- Walking physiology MeSH
- Lower Extremity physiology MeSH
- Adult MeSH
- Electromyography * MeSH
- Isometric Contraction physiology MeSH
- Muscle, Skeletal physiology MeSH
- Humans MeSH
- Young Adult MeSH
- Resistance Training * MeSH
- Cross-Sectional Studies MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
