Combination of Agility and Plyometric Training Provides Similar Training Benefits as Combined Balance and Plyometric Training in Young Soccer Players

Introduction: Studies that combined balance and resistance training induced larger performance improvements compared with single mode training. Agility exercises contain more dynamic and sport-specific movements compared with balance training. Thus, the purpose of this study was to contrast the effects of combined balance and plyometric training with combined agility and plyometric training and an active control on physical fitness in youth.Methods: Fifty-seven male soccer players aged 10–12 years participated in an 8-week training program (2 × week). They were randomly assigned to a balance-plyometric (BPT: n = 21), agility-plyometric (APT: n = 20) or control group (n = 16). Measures included proxies of muscle power [countermovement jump (CMJ), triple-hop-test (THT)], muscle strength [reactive strength index (RSI), maximum voluntary isometric contraction (MVIC) of handgrip, back extensors, knee extensors], agility [4-m × 9-m shuttle run, Illinois change of direction test (ICODT) with and without the ball], balance (Standing Stork, Y-Balance), and speed (10–30 m sprints).Results: Significant time × group interactions were found for CMJ, hand grip MVIC force, ICODT without a ball, agility (4 m × 9 m), standing stork balance, Y-balance, 10 and 30-m sprint. The APT pre- to post-test measures displayed large ES improvements for hand grip MVIC force, ICODT without a ball, agility test, CMJ, standing stork balance test, Y-balance test but only moderate ES improvements with the 10 and 30 m sprints. The BPT group showed small (30 m sprint), moderate (hand grip MVIC, ICODTwithout a ball) and large ES [agility (4 m × 9 m) test, CMJ, standing stork balance test, Y-balance] improvements, respectively.Conclusion: In conclusion, both training groups provided significant improvements in all measures. It is recommended that youth incorporate balance exercises into their training and progress to agility with their strength and power training

Within Session Sequence of Balance and Plyometric Exercises Does Not Affect Training Adaptations with Youth Soccer Athletes

The integration of balance and plyometric training has been shown to provide significant improvements in sprint, jump, agility, and other performance measures in young athletes. It is not known if a specific within session balance and plyometric exercise sequence provides more effective training adaptations. The objective of the present study was to investigate the effects of using a sequence of alternating pairs of exercises versus a block (series) of all balance exercises followed by a block of plyometric exercises on components of physical fitness such as muscle strength, power, speed, agility, and balance. Twenty-six male adolescent soccer players (13.9 ± 0.3 years) participated in an 8-week training program that either alternated individual balance (e.g., exercises on unstable surfaces) and plyometric (e.g., jumps, hops, rebounds) exercises or performed a block of balance exercises prior to a block of plyometric exercises within each training session. Pre- and post-training measures included proxies of strength, power, agility, sprint, and balance such as countermovement jumps, isometric back and knee extension strength, standing long jump, 10 and 30-m sprints, agility, standing stork, and Y-balance tests. Both groups exhibited significant, generally large magnitude (effect sizes) training improvements for all measures with mean performance increases of approximately >30%. There were no significant differences between the training groups over time. The results demonstrate the effectiveness of combining balance and plyometric exercises within a training session on components of physical fitness with young adolescents. The improved performance outcomes were not significantly influenced by the within session exercise sequence

Dominant and nondominant leg press training induce similar contralateral and ipsilateral limb training adaptations with children

International audienceCross-education has been extensively investigated with adults. Adult studies report asymmetrical cross-education adaptations predominately after dominant limb training. The objective of the study was to examine unilateral leg press (LP) training of the dominant or nondominant leg on contralateral and ipsilateral strength and balance measures. Forty-two youth (10-13 years) were placed (random allocation) into a dominant (n = 15) or nondominant (n = 14) leg press training group or nontraining control (n = 13). Experimental groups trained 3 times per week for 8 weeks and were tested pre-/post-training for ipsilateral and contralateral 1-repetition maximum (RM) horizontal LP, maximum voluntary isometric contraction (MVIC) of knee extensors (KE) and flexors (KF), countermovement jump (CMJ), triple hop test (THT), MVIC strength of elbow flexors (EF) and handgrip, as well as the stork and Y balance tests. Both dominant and nondominant LP training significantly (p < 0.05) increased both ipsilateral and contralateral lower body strength (LP 1RM (dominant 59.6%-81.8%; nondominant 59.5%-96.3%), KE MVIC (dominant 12.4%-18.3%; nondominant 8.6%-18.6%), KF MVIC (dominant 7.9%-22.3%; nondominant nonsignificant-3.8%), and power (CMJ dominant 11.1%-18.1%; nondominant 7.7%-16.6%)). The exception was that nondominant LP training demonstrated a nonsignificant change with the contralateral KF MVIC. Other significant improvements were with nondominant LP training on ipsilateral EF 1RM (6.2%) and THT (9.6%). There were no significant changes with EF and handgrip MVIC. The contralateral leg stork balance test was impaired following dominant LP training. KF MVIC exhibited the only significant relative post-training to pretraining (post-test/pre-test) ratio differences between dominant versus nondominant LP cross-education training effects. In conclusion, children exhibit symmetrical cross-education or global training adaptations with unilateral training of dominant or nondominant upper leg

Comparison of Cross-Education and Global Training Effects in Adults and Youth After Unilateral Strength Training

International audienceChaouachi, A, Ben Othman, A, Chaouachi, M, Hechmi, A, Farthing, JP, Granacher, U, and Behm, DG. Comparison of cross-education and global training effects in adults and youth after unilateral strength training. J Strength Cond Res 36(8): 2121-2131, 2022-Youth strength training research examining contralateral, homologous (cross-education), and heterologous (global training) effects after unilateral training have provided mixed results and the relationship to adults has not been compared. The objective was to compare adult and youth cross-education and global training effects on dominant and nondominant limb testing. Initially, 15 men and 15 prepubertal boys volunteered for each unilateral chest press (CP), handgrip training, and control groups (n = 89). Individuals trained their dominant limb 3 times per week for 8 weeks and had their dominant and nondominant limbs tested for CP and leg press 1 repetition maximum (1RM), handgrip, knee extension and flexion, and elbow extension and flexion maximum voluntary isometric contractions (MVICs). Adult CP training gains were significantly greater than youth with lower-body testing (p = 0.002-0.06), whereas youth CP training gains exceeded adults with upper-body tests (p = 0.03-0.07). Training specificity was evident with greater CP 1RM increases with CP vs. handgrip training for both youth (p &lt; 0.0001) and adults (p &lt; 0.0001). Handgrip training elicited greater gains in handgrip MVICs compared with other strength tests (p &lt; 0.0001). In conclusion, only contralateral CP 1RM showed a training advantage for unilateral CP over unilateral handgrip training. Adults showed greater gains with lower-body testing, whereas youth showed greater gains with upper-body testing

Taekwondo Anaerobic Intermittent Kick Test: Discriminant Validity and an Update with the Gold-Standard Wingate Test

International audienceThe aim of this study was to update the validity of the Taekwondo Anaerobic Intermittent Kick Test compared with the 30-s Wingate anaerobic test as the "Gold-Standard", squat jump and countermovement jump tests. The second objective was to examine whether this new specific test would be able to effectively discriminate between elite taekwondo athletes of different competitive levels. Twenty taekwondo athletes (15 males and 5 females) participated in the validation component, whereas 18 (14 males and 4 females) and 16 (13 males and 3 females) athletes participated in the reliability analysis of the Wingate anaerobic test and jumping tests, respectively. They performed these tests on two separate occasions (i.e., test-retest), in addition to the Taekwondo Anaerobic Intermittent Kick Test. To establish test's discriminatory capability (i.e., construct validity), two subgroups were identified based on their international and national taekwondo performance 10 elite (8 males and 2 females) and 9 sub-elite (7 males and 2 females) athletes. Wingate anaerobic test and jumping tests performances showed excellent reliability (ICC > 0.90, SEM < 5% for most variables). Significant correlations between Taekwondo Anaerobic Intermittent Kick Test, Wingate anaerobic test, and jumping tests' variables were mostly "large". Elite taekwondo athletes showed greater taekwondo test performances compared with their sub-elite counterparts (p < 0.001). Receiving operating characteristic analysis indicated that the taekwondo specific test was able to effectively discriminate between elite and sub-elite taekwondo athletes. Overall, the findings of the current study support the concurrent validity of the Taekwondo Anaerobic Intermittent Kick Test. In particular, the Taekwondo Anaerobic Intermittent Kick Test showed good ability to effectively discriminate between taekwondo athletes of different competitive levels

Effect of leg dominance on change of direction ability amongst young elite soccer players

Young soccer players often use one particular dominant leg (DL) to perform dynamic movements which require strength, resulting in leg asymmetry. The aim of this study was to compare, in young soccer players, the effect of using DL and non-dominant leg (NDL) on time performance of two change of direction (COD) manoeuvres in several angles of COD. Seventy-three young male soccer players (mean ± SD, age: 16.1 ± 1.8 year) participated in this study. Players performed 10-m sprints, either in a straight line or with a COD (5 m straight ahead and a turn of 45°, 90°, 135° and 180° to the opposite side of the DL or NDL). Testing for COD speed was conducted over two different manoeuvres: (1) sidestepping and (2) bypass. Maximal isometric voluntary contraction of the knee extensors/flexors and hip abductors/adductors was also measured using a handheld dynamometer. For sidestepping, COD performance with use of the DL was significantly better compared to the NDL (P &lt; 0.05) in all angles of COD. However, bypass COD performance through use of the DL was better compared to the NDL only when turning at 135°. Additionally, strength of the knee extensors/flexors and hip abductors of the DL was significantly (P &lt; 0.05) greater than the NDL. The use of the DL allows better COD performance than the NDL when sidestepping manoeuvre is used. However, the DL allows better COD performance than the NDL only at 135° with the use of the bypass manoeuvre. Furthermore, the greater strength of the DL compared to the NDL may contribute to COD performance difference between legs

'Side-stepping maneuver': not the more efficient technique to change direction amongst young elite soccer players

Two change of direction (COD) maneuvers (Side-Stepping [SSJ and Crossover-Stepping [CR) are often described in the scientific literature. However, there are other COD techniques which have not been investigated Therefore, the main aim of this study was to compare the performance of SS maneuver and a “By-Pass” (BP) COD maneuver (multiple short steps to avoid reduction in running speed by performing longer distance and wider angle of COD compared to SS) over several angles of COD. Seventy-three male soccer players (from U15 and U18 categories) competing at youth level participated in the study. Each age-category was divided into Starters Players (SP) and Non-Starters Players (NSP). Players performed a total of 26 sprints of 10-m, either in straight-line or with a COD (5 m straight ahead and the other 5 m with a turn of 45°, 90°, and 135°) using the two different maneuvers separately: SS and BP. Sprint performance was significantly better at 45°, 90° and 135° CODs (p<0.001) when players performed a BP maneuver compared to SS. Significant age-group effects were revealed, with U18 players demonstrating better performances (p<0.001) than U15 players in all COD angles. Further analysis revealed a significant effect of playing-level, with SP having better performances (p<0.002) compared to NSP in all COD angles. It can be concluded that the BP is a more effective maneuver than SS for changing direction in youth elite soccer players. Also, COD tests with angles ranging between 45° and 135° discriminate between Starters and Non-starters in youth soccer