Change Of Direction Ability Research Articles

Dynamic Strength Index in Basketball Players: Age and Position Differences, Seasonal Variation and Association with Sprinting and Change of Direction Performance

AbstractThe aim of the study was to investigate the differences in bilateral and unilateral dynamic strength index (DSI) between age categories (seniors and juniors), player positions (guards and forwards), its variation during the basketball season, and its association with sprint and change of direction (CoD) performance. Highly trained basketball players (n = 32) performed bilateral and unilateral countermovement jumps (CMJ), bilateral and unilateral isometric squats, 10-m sprint, and 505 CoD test. DSI was calculated from CMJ and isometric peak force, while 10-m sprint and 505 test were used to calculate the CoD deficit. Two-way factorial analysis showed larger isometric peak force in seniors, and larger bilateral DSI in juniors, while guards had higher DSI values and larger peak force in both metrics compared to forwards. Two-way mixed model ANOVA showed a significant increase in unilateral isometric squat and CMJ peak force force (g = –0.08 to –0.64) and increase in bilateral DSI values. Post-hoc analysis showed that isometric squat force significantly increased only in seniors (g = 0.88), resulting in decreased bilateral DSI values (g = 0.52), with bilateral and unilateral DSI values increasing in juniors. Similar trends were observed in guards and forwards, with guards exhibiting a more pronounced increase in all variables compared to forwards. Furthermore, correlation analysis for in-season testing showed moderate associations between isometric squat peak force and CoD ability (r = –0.43 to –0.54; P < 0.001), and weak associations between DSI and CoD ability (r = 0.36 to 0.39; P < 0.05), while associations were not significant for sprint performance. The relationships were lower or absent during pre-season testing. Further interventional studies are needed to determine the usefulness of DSI to guide training related decision-making.

Reliability of phase-specific outcome measurements in change-of-direction tests using a motorized resistance device.

This study aims to determine test-retest reliability of phase-specific information during initial acceleration, deceleration, and re-acceleration phases of different change-of-direction (CoD) tests using a motorized resistance device (MRD). A total of 21 participants (16 males and five females, with mean age of 22.3 ± 3.9 years, body mass of 75.2 ± 6.9 kg, height of 177.9 ± 6.8 cm) completed the modified 505 (m505), 10-0-5, and 15-0-5 CoD tests on four different test sessions while exposed to an external load (3 kg) provided by the MRD. Outcome variables included overall and phase-specific kinetic (force, power, and impulse) and kinematic (time, distance, velocity, and acceleration/deceleration) data during the initial acceleration, deceleration, and re-acceleration phases. The deceleration and re-acceleration phases were further divided into two subphases, namely, early and late subphases, using 50% of maximum velocity. Reliability was assessed using an intraclass correlation coefficient (ICC), coefficient of variation (CV), typical error (TE), and minimal detectable change (MDC). Good to excellent ICC values (>0.75) and acceptable (<10%) to good (<5%) CV values were observed for most outcome measurements. Specifically, 80.1% (822 out of 1,026) of all variables showed good or better relative reliability (i.e., ICC ≥ 0.75), while 97.0% (995 out of 1,026) of all variables showed acceptable or better absolute reliability (i.e., CV < 10%). In conclusion, the present study demonstrates that the MRD can obtain reliable phase-specific outcome measurements across different CoD tests, providing coaches and researchers with new opportunities to advance our understanding of CoD ability and inform more advanced CoD training prescriptions.

Mixed Training Programs Applied to Young Soccer Players: Effects on Speed-Power Abilities.

We compared the effects of two 4-week strength-power-speed training protocols on physical performance of young soccer players. Twenty-three highly trained under-20 soccer players were randomly allocated to two mixed-training groups: 1) "traditional" (TRAD: n=11), comprising vertically oriented strength-power exercises and linear sprints; or 2) "multidirectional" (MULTI: n=12), combining vertically and horizontally oriented strength-power exercises, linear sprints, and change-of-direction (COD) drills. Squat jump (SJ) and countermovement jump, 2) linear sprint, COD speed, and 3) jump-squat (JS) and hip-thrust (HT) power tests were performed pre- and post-training. Differences were determined using a two-way ANOVA with repeated measures and "target scores" were used to detect real changes in performance. No group-time interactions were found for any of the variables (p>0.05). Significant increases (p<0.05) in 20-m sprint velocity, JS- and HT-power were found in both groups, and in SJ in TRAD. Individual analyses revealed a greater number of meaningful changes in zig-zag velocity in MULTI while most players in TRAD displayed meaningful increases in SJ height. In conclusion, both training protocols resulted in similar adaptations but, at the individual level, it appears that MULTI protocol is superior to improve COD ability while TRAD should be preferred to maximize vertical jumping capabilities during short soccer pre-seasons.

The Effects of Workload Difference Between Limbs in Plyometric and Strength Exercises in Reducing Asymmetry in Change of Direction Ability During Basketball Season.

Ujaković, F, and Šarabon, N. The effects of workload difference between limbs in plyometric and strength exercises in reducing asymmetry in change of direction ability during basketball season. J Strength Cond Res 37(11): 2282-2288, 2023-The topic of interlimb asymmetries has recently been extensively investigated; despite that, intervention for purpose of reducing them have been narrowly examined. The present study investigated the effects of maximal strength and plyometric resistance training program with 3:1 workload ratio (nondominant to dominant side) on change of direction deficit (CoDdef) asymmetry during the basketball season. Thirty-six highly trained male basketball players (19.3 ± 4.9 years) from different age categories (U-17, U-19, and senior) were divided into 2 groups: the control group ( n = 18) and the intervention group ( n = 18). The intervention group performed once-a-week training that consisted of strength (Bulgarian split squats) and jumping (single-leg countermovement jumps [SLCMJs]) part in which nondominant-to-dominant workload ratio was 3:1 during the 8-week period. Preintervention and postintervention testing included single-leg isometric squat, SLCMJ, 10-m sprint, and 505 test. Analysis of covariance results showed a statistically significant difference with large effect size ( p < 0.05; η2 = 0.26) when preintervention asymmetry was included as covariate. Post hoc analysis showed a statistically significant decrease in mean CoDdef asymmetry between preintervention (11.88%) and postintervention (4.47%) testing ( p < 0.01, effect size [ES] = -1.37). Isometric squat strength increased on nondominant side in the intervention group ( p < 0.05; ES = 0.77). No other performance or asymmetry variable showed significant change. In conclusion, a 3:1 workload of nonspecific movement task in favor of nondominant limb is an effective training strategy to reduce CoDdef asymmetry during basketball season.

Acute Effect of Four Stretching Protocols on Change of Direction in U-17 Male Soccer Players.

The ability to rapidly change direction while sprinting is a desirable athletic skill in soccer. Enhancing change of direction (COD) performance depends almost exclusively on specific training, with stretching traditionally considered one such intervention. However, the comparative impact of diverse stretching methods on COD in soccer players remains an area of interest. Therefore, this study aimed to compare the effects of different stretching methods on COD ability in soccer players. Twelve male soccer players playing in the national championship football division II (age: 16.3 ± 0.3 years, height: 1.81 ± 0.10 m, body mass: 67.7 ± 7.2 kg) were tested for COD performance (i.e., Illinois agility test) after (1) control condition (20 min general warm-up without stretching), (2) static stretching, (3) dynamic stretching, (4) combined static-dynamic stretching, and (5) combined dynamic-static stretching. The duration of stretching intervention was approximately 6 min for static and dynamic stretching and 12 min for both the combined stretching conditions. The experimental sessions were separated by 72 h. COD improved after dynamic stretching when compared to any other condition (p: 0.03-0.002; ηp2: 0.56-0.73), except for the control condition (p = 0.146; ηp2 = 0.18). In contrast, static stretching induced a detrimental effect on COD when compared only to the dynamic stretching condition (p < 0.01; ES = 1.35). Dynamic stretching exercises used by male soccer players in the warm-up improved COD. Other forms of stretching exercises, particularly static stretching, negatively impacted the COD performance. Therefore, coaches can consider integrating dynamic stretching protocols tailored to the athletes' specific needs. Moreover, extending the investigation to encompass a wider range of athletes, including different age groups and genders, would enhance the applicability and generalization of the findings.

Change of direction speed and deficit over single and multiple changes of direction: Influence of biological age in youth basketball players

ABSTRACT The study analysed the difference in change of direction (COD) deficit among young male basketball players of different age groups and biological ages and analysed the relationships in COD performance (time and deficit) across single and multiple CODs depending on their biological age. Fifty-four highly-trained male players (U-13 and U-17) were tested on sprinting (25-m) and COD ability over single and multiple CODs through total times and the percentage-based COD deficit (CODD). Results showed that older age groups performed significantly (ES = 0.43–2.32, p < 0.05) better in linear and COD times, especially those players with post-peak height velocity (PHV) (ES = 0.89–1.90). Controlling for age at PHV, no significant differences were found in any group or inter-limb asymmetries. Moderate relationships were found between CODD in the pool data (r = 0.36 to 0.50). All CODD and time relationships in any test (i.e., 180º COD and V-cut) were considerably lower (r= −0.27 to 0.32) across individual biological groups. The study highlights the impact of maturation on COD performance, whereas CODD seems to be not affected. Interestingly, the CODD is independent, highlighting this measurement’s specific nature. Practitioners should use common distances, angles, and the number of CODs linked to biological status to create a COD profile.

The relationship between relative lower-body strength, sprint and change of direction ability in elite youth female soccer athletes

Soccer is described as a high-intensity, multidirectional sport requiring athletes to possess a high level of physical conditioning to compete at the elite level. Strength, linear sprint and change of direction (COD) abilities are key physical characteristics in soccer-specific performance, with research suggesting athletes who possess greater relative lower-body strength are superior in sprint and COD ability. The purpose of this study was to investigate the relationship between relative lower-body strength with linear sprint and COD ability among elite youth female soccer athletes in Western Australia. Forty-four (U13, n = 11; U14, n = 12; U15, n = 11; U19, n = 10) athletes completed an isometric mid-thigh pull (IMTP), 30 m sprint and 505 COD test. Results demonstrated a significant moderate correlation between relative IMTP (IMTPr) performance and 10 m ( r = −0.315, p = 0.037) and 30 m ( r = −0.0347, p = 0.021) sprint time, however, there was no significant correlation between IMTPr performance and COD deficit ( r = −0.227, p = 0.168). This study suggests that relative lower-body strength is moderately related to greater sprint performance but not COD ability in elite youth female soccer athletes. Overall, relative lower-body strength appears to be advantageous to linear sprint performance in elite youth female soccer athletes, and therefore the inclusion of appropriate and targeted strength training in the physical preparation and long-term athlete development of this demographic may be recommended.

The Relationship of Anthropometric and Physical Performance Characteristics on Competitive Success in Amateur, Elite, and Professional Rodeo Athletes.

Oranchuk, DJ, Gullett, LK, Kicia, M, Thome, B, and Game, A. The relationship of anthropometric and physical performance characteristics on competitive success in amateur, elite, and professional rodeo athletes. J Strength Cond Res 37(7): 1495-1506, 2023-Reference anthropometric and physical performance qualities can improve understanding of sporting needs and streamline preparation and rehabilitation programs. However, these data and their relationships with competitive success are absent in rodeo athletes. We hypothesized that riding performance would be most correlated with hip adductor, neck, and grip strength, whereas jump, reactive strength index (RSI), and change of direction abilities would best predict bull-fighting performance. Forty-three amateur ( n = 9), professional ( n = 23), or internationally ranked ( n = 11) male rodeo athletes (bareback = 9, bull riders = 16, saddle bronc = 7, bullfighters = 11) (26.8 ± 5.6 years) volunteered for this study. Anthropometrics included body mass, height, and body fat percentage. Performance measures included isometric hip adduction and abduction, neck flexion and extension, handgrip strength, squat and countermovement jump heights, eccentric utilization ratio, reactive strength index, change of direction, bike sprints, and several pneumatic power measures. Bullfighters were taller and heavier than bull riders (effect size [ES] = 0.84-0.87, p = 0.008-0.017). Bull riders were leaner than bullfighters (ES = 0.74, p = 0.012). Fighters had greater RSI than riders (ES = 0.73-1.47, p < 0.001-0.030). Competitive level of rodeo riders ( n = 32) correlated with age, rodeo experience (ρ = 0.37-0.43, p = 0.013-0.049), bent-leg abduction (ρ = 0.43, p = 0.014), straight-leg hip adduction and abduction (ρ = 0.49-0.56, p < 0.001-0.005), neck flexion force (ρ = 0.43, p = 0.016), and rotational power (ρ = 0.50, p = 0.004). The competitive level of the fighters correlated with age (ρ = 0.64, p = 0.036) and time trial performance (ρ = -0.76, p = 0.006). This is the first study providing normative and correlational strength and power performance data in a rodeo population. These data highlight the need for more event-specific physical preparation. Riders should focus their physical preparation on hip and neck strength and rotational power. Bullfighters should prioritize stiffness and anaerobic power.

Association between 2D:4D ratios and sprinting, change of direction ability, aerobic fitness, and cumulative workloads in elite youth soccer players

BackgroundThe aim of this study was two-fold: (i) to determine the correlation between 2D:4D, maximal oxygen uptake (VO2max), body fat percentage (BF%), maximum heart rate (HRmax), change of direction (COD), and accumulated acute and chronic workload variables; (ii) to verify if the length of the second digit divided by fourth digit (2D:4D) can explain fitness variables and accumulated training load.MethodsTwenty elite young football players (age: 13.26 ± 0.19 years; height: 165.8 ± 11.67 cm; body mass: 50.70 ± 7.56 kg; VO2max, 48.22 ± 2.29 ml.kg− 1.min− 1) participated in the present study. Anthropometric and body composition variables (e.g., height, body mass, sitting height, age, BF%, body mass index, right and left finger 2D:4D ratios) were measured. The following fitness tests were also conducted: 30 − 15 Intermittent Fitness Test (VO2max and HRmax), COD (5-0-5 agility test), and speed (10-30msprint test. HRmax and the training load were also measured and monitored using the Rate of Perceived Exertion during the 26 weeks.ResultsThere were associations between HRmax and VO2max, between 2D and 4D lengths and Left and Right hand ratios. Also, in AW with Right and Left 4D. The CW and de ACWR with the Right 4D. There were other associations between physical test variables and workload variables.ConclusionsUnder-14 soccer players with low right and left-hand 2D:4D ratios did not perform better in the selected fitness tests to assess VO2max, COD, or sprint ability. However, it cannot be ruled out that the absence of statistically significant results may be related to the small sample size and the maturational heterogeneity of the participants.

Revisiting the Assessment of Strength, Power, and Change of Direction in Collegiate American Football Athletes.

Burke, AA, Guthrie, BM, Magee, M, Miller, AD, and Jones, MT. Revisiting the assessment of strength, power, and change of direction in collegiate american football athletes. J Strength Cond Res 37(8): 1623-1627, 2023-The primary purpose was to assess the effect of strength on vertical jump (VJ) and change of direction (COD) with a secondary purpose to examine if these relationships were moderated by the sport position group through path analysis using structural equation modeling. Subjects were collegiate American football athletes grouped by skill (SK; n = 98) and nonskill (NS; n = 83) sport position groups. Maximal strength was assessed by 1 repetition maximum back squat and hang clean (HC). Vertical jump was used to evaluate power. Change of direction was assessed through the 20-yard shuttle (i.e., 5-10-5) test. Multigroup path analysis examined causal pathways among variables and moderating effects of sport position. The final model revealed that VJ fully mediated the relationship between HC and COD (HC-VJ: β = 0.408, p < 0.001; VJ-COD: β = -0.376, p < 0.001; and HC-COD: β = -0.137, p = 0.17) in SK. The NS showed only direct effects of HC on COD ( β = -0.335, p < 0.001). These findings suggest that strength does not solely explain COD ability but also can serve to enhance underpinning qualities, such as relative force production in the VJ. Relationships between strength, power, and COD are different depending on the positional group. The results provide further insight into performance outcomes in field tests. It is recommended that sport position differences be considered when assessing and analyzing physical qualities in a team setting within the sport of American football.

Relationship Among the Change of Direction Ability, Sprinting, Jumping Performance, Aerobic Power and Anaerobic Speed Reserve: A Cross-Sectional Study in Elite 3x3 Basketball Players.

The main purpose of this study was to determine the relationships among sprinting performance, change of direction ability (COD), change of direction deficit (CODD), and aerobic power expressed by maximal oxygen velocity (VmaxIFT), anaerobic speed reserve (ASR) as well as jumping performance (countermovement jump with (CMJa) and without an arm swing (CMJ)) in elite 3x3 basketball players. A total of 15 Polish Olympic 3x3 team players (age: 26.86 ± 8.28 years; body height: 191 ± 5.33 cm; body mass: 90.68 ± 10.03 kg, basketball experience: 15.53 ± 5.8 years) participated in the study. Athletes were tested for the following measures: the linear speed at the first section (5 m), the second section (9 m), the third section (10 m) and total distance (24 m), two sets; the 30-15 Intermittent Fitness Test (first session); COD speed by the Change of Direction and Acceleration Test (CODAT) (the same sections and total distance as in the linear speed test), five repetitions, two sets; and jumping performance by the CMJ with and without an arm swing (second session). CODD was calculated by subtracting the COD speed time from linear speed time at adequate sections and total distance. Maximal sprinting speed (MSS), maximal aerobic velocity (VmaxIFT), and anaerobic speed reserve (ASR) were also considered. Anaerobic Speed Reserve (ASR) was calculated as the difference between MSS and VmaxIFT. A Pearson's correlation test was used to determine the relationship between power-speed-related variables and CODD, final velocity attained at the 30-15 Intermittent Fitness Test (VmaxIFT), ASR, and COD performance. Moderate to strong correlations were registered between COD and linear speed at 5, 10, and 24 m, while moderate to strong negative correlations were detected between COD, CODD, and CMJ, CMJa. Moreover, moderate to strong correlations were observed between COD, CODD, and VmaxIFT, MSS at 9, 10, and 24 m sprints. No relationship was detected between COD, CODD, LS, and ASR in any measured sector. Finally, statistically significant differences were registered in COD and CODD between trial 1 and trial 2.

Change of Direction Ability as a Sensitive Marker of Adaptation to Different Training Configurations, and Different Populations: Results from Four Experiments.

This article includes four separate experiments. In the first experiment male beach handball players (n = 24) were randomly assigned to regular training (n = 12) or plyometric and sprint training (n = 12). In the second experiment, male players were assigned to a handball practice only (n = 12), a plyometric training (n = 12), or an eccentric-overload (e.g., versa-pulley machine) training group (n = 12). In the third experiment, participants were assigned to padel training (n = 12) or specific on-court neuromuscular technical actions (n = 12). In the fourth experiment, females between 50-59 years (n = 25), 60-64 years (n = 25), and 65-70 years (n = 25) completed 10 weeks of bench stepping training involving jumps, and were compared to age-matched controls (n = 45). The COD ability was assessed with the 10-m COD ability test (experiments one and two), the COD ability test with 90º and 180º turns (third experiment), and with the timed-up-and-go test (fourth experiment). In experiment one, greater COD improvement was noted in the experimental group compared to the control group (p < 0.05). In experiment two, both intervention groups similarly improved COD when compared to the control group (p < 0.05). In experiment three, although no significant group-time interactions were observed for COD, the experimental group improved all COD measures pre-post-training (p < 0.05), with a larger effect size for COD with 180° turn to the right compared to the control group (effect size = 0.8 vs. 0.3). In experiment four, the three training groups improved COD ability compared to the control group (p < 0.05). In conclusion, COD is a sensitive marker of adaptation to different training configurations in these diverse groups.

Comparison of two 8-week training interventions on the athletic performance of padel players

Padel is an intermittent racket sport played in pairs (2 vs. 2) on a small-sized grass court (20 x 10 m), involving high physical fitness demands for the players. Therefore, this study aims to compare the effect of two 8-week in-season training programs on the athletic performance of male padel players. Participants (age, 22.1±0.8; body height, 182.0±1.0; body mass, 74.7±0.7) were randomly assigned to the integrated training group (IG, n=12) and non-integrated training group (NIG, n=12). The IG trained inside the padel court, integrating neuromuscular exercises with sport-specific (i.e., use of the racket) technical actions. The NIG trained outside the padel court, performing the same neuromuscular exercises and sport-specific technical actions as the IG, although not simultaneously. Before and after the intervention, athletes were assessed for their hand-grip strength, two legged and one-legged Abalakov jump, bench press performance, padel stroke velocity, cardiorespiratory endurance (30-15IFT), 5-m and 10-m linear sprint time and change of direction ability at 90º and 180º using left and right leg. Both groups improved their scores on Abalakov jump tests, bench press performance, stroke velocity, cardiorespiratory endurance (30-15IFT), and change of direction ability at 90º and 180º (all changes p&amp;lt;.05; effect size = 0.22-2.58). The IG improved stroke velocity compared to NIG (p&amp;lt;.05), and only the IG showed pre-post improvements (p&amp;lt;.05; effect size = 0.30-0.76) in change of direction ability at 90º and 180º involving the non-dominant leg (i.e., turn to the right). An 8-week in-season integrated training approach and a non-integrated training approach may induce similar improvements in athletic performance among highly trained male padel players. However, the neuromuscular training program involving an integration of padel-specific and non-specific training exercises may induce greater improvements in padel-specific performance (i.e., stroke velocity) and change of direction speed ability, particularly in movements involving the non-dominant leg.

Assessment of Change of Direction and Agility. Running and Dribbling among Soccer, Basketball and Handball Players: The Concept of “Agility deficit”

The primary objective of this study is to conduct a comparative analysis of change of direction (COD) and agility among players engaged in soccer, basketball, and handball. Additionally, the researchers introduced the novel concept of “Agility deficit”, aimed at evaluating distinctions between COD and agility during running (COD-R; Agility-R) and dribbling (COD-D; Agility-D). The participant cohort comprises 38 individuals with an average age of 20.63 years, distributed across 13 handball players, 12 soccer players, and 13 basketball players. Statistical analyses, specifically ANOVA accompanied by Tukey’s post hoc comparisons, have been employed to discern significant differences among subgroups. While no noteworthy disparities among groups were observed in both COD-D and Agility-D when participants manipulated the balls using their hands, a marked superiority in performance emerged for soccer players when the balls were manipulated with their legs. Soccer players exhibited expedited responses compared to their basketball and handball counterparts when confronted with a visual stimulus during the Agility-R test (reduced Agility-R deficit). Furthermore, the Agility-D deficit underscored the heightened visual challenge to react in visual stimuli during dribbling in soccer. Independent of the type of ball handling, soccer players consistently demonstrated a diminished Agility-D deficit, affirming their superior visual ability. The performance in Agility-D further revealed that visual ability plays a pivotal role in influencing dribbling ability. The study posits that, for a comprehensive assessment of a player’s visual ability during running or dribbling, interpretations of both Agility-R deficit and Agility-D deficit are imperative. Consequently, the proposed indexes of Agility-R deficit and Agility-D deficit present valuable tools for evaluating players’ COD and Agility abilities during running or dibbling. However, the efficacy of these assessments in real-game situations remains undetermined, requiring further investigation.

Effects of different maturity status on change of direction performance of youth tennis players.

The aim of this study was to examine the maturational status (i.e., peak height velocity [PHV]) differences in neuromuscular performance (i.e., vertical jump, linear sprint, change of direction (COD) using different tests, and change of direction deficit [CODD]) of young tennis players. One hundred and two tennis players (70 boys and 52 girls; age 13.9 ± 2.0 years, body mass 53.3 ± 12.7 kg, height 163.1 ± 11.9 cm) participated in the study and were divided into Pre-PHV (n = 26), Circa-PHV (n = 33) and Post-PHV (n = 43) groups. Testing included speed (5, 10, and 20 m), COD tests (i.e., modified 5-0-5, pro-agility and hexagon), and bilateral/unilateral countermovement jump (CMJ). Pre- and Circa-PHV players presented lower levels of performance in jumping ability (i.e., both bilateral and unilateral CMJs; P < 0.001; ES: 0.85 to 0.98), linear sprints (5 to 20 m; P < 0.05 to < 0.001; ES: 0.67 to 1.19) and COD ability tests (modified 5-0-5 test, pro-agility and hexagon) compared to the Post-PHV players. Moreover, Pre-PHV players presented lower CODD% (p < 0.05; ES: 0.68-0.72) than Post-PHV for both forehand and backhand sides, and Circa-PHV showed lower values in the CODD of the rolling situation to the forehand side (p < 0.05; ES: 0.58). Among the COD tests, the pro-agility test seems to be a simple, easy-to-implement and reliable test, which can provide interesting information about the COD with higher entry speeds. Moreover, specific training strategies related to the PHV and focused not only on the neuromuscular training and COD workouts, but also on maximizing motor skill proficiency, should be recommended.

The Effects of Different Training Interventions on Soccer Players’ Sprints and Changes of Direction: A Network Meta-Analysis of Randomized Controlled Trials

Objective: To compare and rank the effects of different training interventions on the sprint and change of direction (COD) abilities of soccer players using a network meta-analysis. Methods: The PubMed, Cochrane, and Web of Science databases were searched for papers published up to June 2022. Inclusion criteria: (1) No distinction was made between nationality, region, or gender. No distinction was made between physical activity times or habits. Healthy and disease-free soccer players (age ≥ 18 years old) were eligible. (2) Different training methods and their combinations were used. (3) Groups of either no training or single training, or combined training were included. (4) Randomized controlled trials (RCTs) were included. (5) The outcome indicators included at least one of the following: sprint, agility, and change of direction (COD). Exclusion criteria: (1) studies in non-English were not included. (2) Individual studies, general public studies, literature review studies, qualitative studies, case studies, and studies with unclear data such as means and standard deviations were not included. (3) Studies using the same data were not included. (4) Interventions that could not be statistically analyzed because of insufficient numbers of studies were not included. RCTs that satisfied the inclusion criteria were included. Paired analyses and network meta-analyses were performed using random-effects models. The included studies were assessed using the Cochrane risk-of-bias assessment tool. The surface under the cumulative ranking curve (SUCRA) metric was used to rank the effectiveness of each treatment and identify the best treatment. Results: The network meta-analysis (NMA) included eleven RCTs with a total of two-hundred and seventy-seven participants and six interventions: plyometrics combined with sprint, agility, and resistance training (P+T+S+A), plyometrics combined with sprint and agility training (P+S+A), resisted sprinting combined with agility training (RS+A), plyometric training (P), resistance training (T), soccer skills, and a strategy training control group (C). P+T+S+A ranked highest in terms of improving soccer players’ 10 m sprint performance (SUCRA = 70.2%) and COD (SUCRA = 75.0%). P+S+A ranked highest in terms of improving soccer players’ 20 m sprint performance (SUCRA = 69.8%). Conclusions: Based on the network meta-analysis, for combined training, P+T+S+A was more effective at improving the sprinting and COD ability of soccer players. In the single training mode, plyometric training was the most effective. To improve sprint and COD ability, P+T+S+A should be chosen. Such improvements may be expected after P+T+S+A interventions for a duration of six or more weeks. However, gender, competitive level, and other factors will affect the assessment results. Given the limitations of the above analysis, these results should be interpreted with caution.

Match Loads May Predict Neuromuscular Fatigue and Intermittent-Running Endurance Capacity Decrement after a Soccer Match.

How the match-derived load metrics relate to post-match fatigue in soccer is scarcely researched. Thus, the aim of this study was to determine the associations between soccer match-related internal and external loads, neuromuscular performance decrease and intermittent-running endurance capacity decrement immediately post-match. Vertical jump (countermovement jump), straight-line sprinting (10- and 20-m sprint), change of direction ability (T-test) and intermittent-running endurance capacity (YO-YO intermittent recovery level 2) were measured one day before and immediately after a friendly match in male soccer players. During the match, players' internal and external loads were also monitored, including heart rate-derived indices, total distance at various speed thresholds, average running velocity, maximal running velocity, number of sprints and number of accelerations and decelerations at various intensity thresholds. The results show that match-induced fatigue was reflected on neuromuscular performance and intermittent-running endurance capacity immediately post-match (p &lt; 0.05). The quantification of percentage change of match external-load metrics, particularly accelerations and decelerations, provides a useful non-invasive predictor of subsequent neuromuscular fatigue status in soccer players immediately post-match (p &lt; 0.05). However, only internal load metrics present a practical application for predicting intermittent-running endurance capacity impairment (p &lt; 0.05). In summary, internal and external load metrics may allow for predicting the extent of acute fatigue, and variability between halves may represent a valuable alternative to facilitate the analysis of match-related fatigue both for research and applied purposes.

The influence of short sprint performance, acceleration, and deceleration mechanical properties on change of direction ability in soccer players-A cross-sectional study.

The study investigated the relationship between short sprint performance and mechanical parameters obtained during the acceleration and deceleration tasks with the change of direction (COD) performance in female and male soccer players. The acceleration and deceleration ability were compared in the "High/Fast" versus "Low/Slow" COD performance group based on a median split analysis in each sex group. One hundred three French soccer players were assessed for the sprinting Force-Velocity (F-V) profile (i.e., theoretical maximal force [F0], velocity [V0], power [Pmax]), 10m performance, linear deceleration test (maximal braking force [HBFmax], braking power [BPmax], deceleration [Decmax]), and COD performance using 505-test. The 10m performance was strongly associated with 505-test performance (ES = [0.64 to 0.71]), whereas the sprinting F-V profiles parameters were weakly to moderately correlated with 505- performance (ES = [-0.47 to -0.38]). The BPmax was also moderately associated with 505-test performance (ES: range = [-0.55 to -0.46]). In addition, the High/Fast female COD group presented higher F0, Pmax, HBFmax, and BPmax than the Low/Slow group, whereas the male groups presented very few mechanical differences. Multiple regression analysis shows that the COD performance of male players was determined by 10m performance and maximum deceleration power. In contrast, no statistically significant model could be found to determine the change of direction performance in female players. In conclusion, the current finding indicated that the only variable strongly associated with COD performance was the linear 10m sprint time. In the same way, the mechanical parameters obtained from acceleration and deceleration seemed to play a non-neglectable role in this population.

Ability of functional performance assessments to discriminate athletes with and without chronic ankle instability : a case-control study.

BackgroundThe decline in motor function associated with chronic ankle instability (CAI) can be assessed using Functional Performance tests. Ankle muscular strength, endurance and range of motion (ROM) has been assessed in previous studies but functional activities such as sprinting and change of direction are less well studied in athletes with CAI. Hence the aim of this study was to determine how sprint, change of direction, ankle isometric strength, endurance and ROM measures may be associated with discriminate athletes with and without CAI.MethodsOne hundred and six participants (CAI: n = 53 or no CAI: n = 53) provided informed consent to participate in this study. Participants performed three functional performance tests, (30-m sprint test, Modified Illinois change of direction test (MICODT)) and change of direction test. Range of motion for dorsiflexion was measured using weight bearing lunge test and inversion, eversion and plantarflexion using Saunders® digital inclinometer. Strength was assessed using Baseline® hand-held dynamometer for plantarflexors, dorsiflexors, invertors and evertors. Muscular endurance was assessed by single heel raise test and Modified single heel raise test. Between-group comparisons utilised Student’s t-test and Mann-Whitney U-tests, with a number of unique variable and multivariable binomial logistic regression performed to determine which performance measures may discriminate participants with CAI.ResultsThe CAI participants performed significantly worse in the three functional performance tests as well as multiple measures of ankle ROM, isometric strength and muscular endurance (p < 0.008). While several measures of ROM (plantarflexion and dorsiflexion), strength (inversion and eversion) and both muscular endurance tests were significantly associated with CAI in the univariable analysis, the strongest association was the functional performance tests, especially MICDOT time (odds ratio (95% CI): 0.06 [0.02–0.17], sensitivity 94.3%, specificity 88.7%). Multivariable regression analyses indicated that performance across the functional performance tests were more strongly associated with CAI than any ankle ROM, muscular strength or endurance test. Further, the inclusion of the best ankle range of motion, strength or muscular endurance tests did not significantly improve upon the association of the MICDOT with CAI.ConclusionsChronic ankle instability in athletic populations appears to be highly associated with declines in functional performance and to a somewhat lesser extent, ankle range of motion, strength and muscle endurance measures. This may suggest that optimal rehabilitation for athletes with CAI may require a greater focus on improving sprinting speed and change of direction ability in the mid to latter stages of rehabilitation, with regular assessments of these functional performance tests necessary to guide the progression and overload of this training.

Relationship between Variations in the Accumulated Workload and the Change of Direction Ability in Elite Young Soccer Players

Background: The main aim of this study was to evaluate the relationships between training workload (WL) parameters with variations in the change of direction (COD) in under-16 soccer players. Methods: Twenty-seven under-16 elite soccer players were daily monitored for their WL across 15 weeks during the competitive soccer season. Additionally, players were assessed two times for anthropometric measures (weight, height, sitting height and leg length), COD performance (modified 505 test) and maturity offset measured using the peak height velocity (PHV). Results: A correlational analysis was performed to determine the relationship between the variation in COD performance and accumulated WL parameters. Moreover, a regression analysis was executed to explain the variations in the percentage of COD performance considering the accumulated WL parameters and PHV of the season (r = 0.93; p ≤ 0.01) and training monotony during the early-season (r = 0.53; p ≤ 0.05). There were associations between the acute workload during the start of the season and the COD during the end of the season (r = 0.47; p ≤ 0.05). The multiple linear regression analysis showed that 55% of the variation in COD performance between the early and end of season could be explained by the acute or chronic WL, training monotony or strain and the PHV. Conclusions: This information might be useful for practitioners and coaches aiming to improve the COD performance in youth soccer players during an entire competitive season.