Effects of a feint on reactive agility performance

Abstract

This study compared reactive agility between higher-standard (n = 14) and lower-standard (n = 14) Australian footballers using a reactive agility test incorporating a life-size video image of another player changing direction, including and excluding a feint. Mean agility time in the feint trials was 34% (509 ± 243 ms; p < 0.001; effect size 3.06) longer than non-feint trials. In higher-standard players, agility time was shorter than for lower-standard players in both feint (114 ± 140 ms; p = 0.18; effect size 0.52; likely beneficial) and non-feint (32 ± 44 ms; p = 0.22; effect size 0.47; possibly beneficial) trials. Additionally, the inclusion of a feint resulted in movement time increasing over three times more in the lower-standard group (197 ± 91 ms; p = 0.001; effect size 1.07; almost certainly detrimental) than the higher-standard group (62 ± 86 ms; p = 0.23; effect size 0.66; likely detrimental). There were weak correlations between the feint and non-feint trials (r = ?0.13–0.14; p > 0.05), suggesting that reactive agility involving a feint is a unique skill. Also, higher-standard players are more agile than their lower-standard peers, whose movement speed deteriorates more as task complexity increases with the inclusion of a feint. These results support the need for specific training in multi-turn reactive agility tasks.     

Effects of small-sided game and change-of-direction training on reactive agility and change-of-direction speed

Abstract

The purpose of this study was to determine the effects of training change-of-direction speed and small-sided games on performance in the Planned-AFL agility test and reactive agility. Twenty-five elite-standard U-18 Australian Rules football players were randomly allocated either to a change-of-direction group or a small-sided games group. Players participated in one or two 15-min sessions per week with 11 sessions conducted over a 7-week period during the season. Tests conducted immediately before and after the training period included the Planned-AFL agility test and a video-based reactive agility test specific to Australian Rules football. The reactive agility test variables were total time, decision time and movement response time. The small-sided games group improved total time (P = 0.008, effect size = 0.93), which was entirely attributable to a very large reduction in decision time (P < 0.001, effect size = 2.32). Small-sided games produced a trivial change in movement response time as well as in the Planned-AFL agility test (P > 0.05). The change-of-direction training produced small to trivial changes in all of the test variables (P > 0.05, effect size = 0–0.2). The results suggest that small-sided games improve agility performance by enhancing the speed of decision-making rather than movement speed. The change-of-direction training was not effective for developing either change-of-direction speed as measured by the Planned-AFL test or reactive agility.     

Effects of a contrast training programme on jumping,sprinting and agility performance of prepubertal basketball players

The purpose of this study was to examine the effects of a 10 week contrast training (CT) programme (isometric + plyometric) on jumping, sprinting abilities and agility performance in prepubertal basketball players. Fifty-eight children from a basketball academy (age: 8.72 ± 0.97 years; body mass index: 17.22 ± 2.48 kg/m²) successfully completed the study. Participants were randomly assigned to experimental groups (EG, n = 30) and control groups (CG, n = 28). The CT programme was included in the experimental group’s training sessions – twice a week – as part of their usual weekly training regime. This programme included 3 exercises: 1 isometric and 2 plyometric. Jumping, sprinting and agility performance were assessed before and after the training programme. Significant differences were found in posttest between EG and CG in sprint and T-test: EG showed better results than CG. Furthermore, there were significant differences in posttest-pretest between EG and CG in squat jump, countermovement jump, drop jump, sprint and T-test with the EG showing better results than CG. The CT programme led to increases in vertical jump, sprint and agility levels, so that the authors suggest that prepubertal children exhibit high muscular strength trainability.     

The influence of ankle dorsiflexion on jumping capacity and the modified agility t-test performance

Abstract

Dorsiflexion sport shoes aim to increase jumping capacity and speed by means of a lower position of the heel in comparison with the forefoot, favouring additional stretching of the ankle plantar flexors. In previous studies, contradictory results have been found on the benefits of using this type of shoe. With the aim of comparing a dorsiflexion sport shoe model (DF) with a conventional sport shoe (CS), 41 participants performed a countermovement jump (CMJ) test and an agility test (MAT) with both models of shoe. There were no significant differences in the jump test [CS=35.3 cm (6.4) and DF=35.6 cm (6.4), P>0.05]. In the agility test, the conventional shoe obtained better results than the model with dorsiflexion with regard to time taken to complete the circuit [CS=6236 ms (540) and DF=6377 ms (507), P<0.05)]. In spite of producing pre-stretching of the plantar muscles, the DF sport shoes were not effective for improving either jump power or agility in a specific test.     

The acute effects of vibration stimulus following FIFA 11+ on agility and reactive strength in collegiate soccer players

PurposeThe aim of this study was to assess the effects of combining the FIFA 11+ and acute vibration training on reactive strength index (RSI) and 505 agility.MethodsSeventy-four male collegiate soccer players took part in the study and were randomly assigned to FIFA 11+ with acute vibration group (FIFA + WBV), FIFA 11+ with isometric squat group (FIFA + IS) or a control group consisting of the FIFA 11+ alone (Con). The warm-up consisted of the FIFA 11+ and was administered to all participants. The participants in the acute vibration group were exposed to 30 s whole body vibration in squat position immediately post warm-up. The isometric group completed an isometric squat for 30 s immediately post warm-up.ResultsRSI significantly improved pre- to post-intervention amongst FIFA + WBV (p < 0.001) due to a decrease in contact time (p < 0.001) in comparison to FIFA + IS and Con, but 505 agility was not affected.ConclusionThe results of this study suggest the inclusion of an acute bout of WBV post FIFA 11+ warm-up produces a neuromuscular response leading to an improvement in RSI. Future research is required to examine the exact mechanisms behind these improvements amongst other populations and over time course of the performance.     

动作识别对运动员心理敏捷性的影响

动作识别运动员在做出动作反应之前,对所知觉的对象进行辨认并将知对象与其他动作区分开来,获得未来动作反应信息的过程。动作识别能力受训练水平的影响,运动员在动作识别能力上的差异是直接影响其在对抗性运动中心理敏捷性或认辞别中工速度的主要因素之一。     

Collegiate baseball players with more optimal functional movement patterns demonstrate better athletic performance in speed and agility

Sports injuries are common among baseball players and may result in abnormal movement patterns, increased risks of future injury, and unsatisfactory performance. The Functional Movement Screen (FMS?) has been developed to detect abnormal functional movement patterns and can be used for predicting risks of sports injury. However, whether FMS? scores are associated with athletic performance remains unclear. The goal of this study was to determine the association between functional movements and athletic performance in elite baseball players. Core stability, muscular strength and flexibility of the lower extremities, and FMS?, as well as athletic performance in sprinting, agility, and balance tests were assessed in 52 male collegiate Division I baseball players placed into two groups based on FMS? scores. The high-scoring group demonstrated better athletic performance than the low-scoring group, with a shorter duration of the agility test. No group differences were found in core stability, muscular strength, or muscle flexibility, except for rectus femoris flexibility. Thus, the FMS? score is associated with sprinting and agility performance in elite baseball players. These findings indicate that the FMS? may have a role in predicting athletic performance and thereby help determine the goals of training regimens or return-to-play strategies.     

Effects of fatigue on golf performance

The purpose of this study was to determine if body position, weight transfer, and/or pelvis/trunk rotations changed as a result of a golf specific fatiguing protocol and whether these changes affected resultant club head velocity at impact and shot consistency. Six male golfers and one female golfer participated in the study, who had a mean age, height, and body mass of 23.9 +/- 3.9 years, 177.4 +/- 4.9 cm, and 75.3 +/- 9.9 kg, respectively. Path analysis was used to determine the relationships between fatigue, biomechanical variables, and resultant club head velocity at impact and shot consistency. In the statistical models representing the effects of biomechanical variables calculated at the top of the swing and ball contact, golf specific fatigue was associated with a 2.0% and 2.5% reduction in the club head velocity and a 7.1% and 9.4% improvement in the shot consistency, respectively. These data suggest that golf specific fatigue was not related to the initial lower body sagittal plane angles at address nor was simulated golf specific fatigue related to peak transverse plane pelvis and trunk rotational velocities (or their timings) in a manner that indicates a relationship to resultant club head velocity and shot consistency.     

Physical demand of seven closed agility drills

The present study aimed to quantify the demand of seven generic, closed agility drills. Twenty males with experience in invasion sports volunteered to participate in this study. They performed seven, closed agility drills over a standardised 30-m distance. Physical demand measures of peak velocity, total foot contacts, peak impacts, completion time, and maximum heart rate were obtained via the use of wearable sensor technologies. A subjective rating of perceived exertion (RPE) was also obtained. All measures, with the exception of maximum heart rates and RPE were able to delineate drills in terms of physical and physiological demand. The findings of this study exemplify the differences in demand of agility-type movements. Drill demand was dictated by the type of agility movement initiated with the increase in repetitiveness of a given movement type also contributing to increased demand. Findings from this study suggest agility drills can be manipulated to vary physical and physiological demand. This allows for the optimal application of training principles such as overload, progression, and periodisation.     

Effects of forefoot bending stiffness of badminton shoes on agility,comfort perception and lower leg kinematics during typical badminton movements

This study investigated whether an increase in the forefoot bending stiffness of a badminton shoe would positively affect agility, comfort and biomechanical variables during badminton-specific movements. Three shoe conditions with identical shoe upper and sole designs with different bending stiffness (Flexible, Regular and Stiff) were used. Elite male badminton players completed an agility test on a standard badminton court involving consecutive lunges in six directions, a comfort test performed by a pair of participants conducting a game-like practice trial and a biomechanics test involving a random assignment of consecutive right forward lunges. No significant differences were found in agility time and biomechanical variables among the three shoes. The players wearing the shoe with a flexible forefoot outsole demonstrated a decreased perception of comfort in the forefoot cushion compared to regular and stiffer conditions during the comfort test (p < 0.05). The results suggested that the modification of forefoot bending stiffness would influence individual perception of comfort but would not influence performance and lower extremity kinematics during the tested badminton-specific tasks. It was concluded that an optimisation of forefoot structure and materials in badminton shoes should consider the individual’s perception to maximise footwear comfort in performance.     

Effects of multicycle-run training on triathlete performance

The purpose of this study was to determine the effect of triathlon training using multiple, short cycle-run sequences (multicycle-run training) on cycle-run performance. Twelve competitive triathletes, randomized into two groups, underwent multicycle-run training or normal training for 6 weeks. During this period, baseline training remained the same for both groups, and only the high-intensity component differed. The differentiated exercises were performed at or above 100% maximal aerobic velocity. The improvements in overall cycle-run performance were similar (3.3 +/- 1.4 % and 6.1 +/- 1.7% rise in Performance in multicycle-run and normal training, respectively). However, the improvement in performance was significantly greater for the multicycle-run training (-11.2 +/- 6.8 s versus -1.2 +/- 7. 7 s for multicycle-run training and normal training, respectively) during both the cycle-run change and the first 333-m lap, which together are termed the cycle-run transition. We concluded that 6 weeks of multicycle-run training did not induce greater improvement in cycle-run performance than did normal training in competitive triathletes. However, it did induce significant improvement in the cycle-run transition. This finding indicates that multicycle-run training may help competitive triathletes to develop greater skill and better physiological adaptations during this critical transition period of the triathlon race.     

Effects of inter-limb asymmetries on physical and sports performance: a systematic review

The prevalence of inter-limb asymmetries has been reported in numerous studies across a wide range of sports and physical qualities; however, few have analysed their effects on physical and sports performance. A systematic review of the literature was undertaken using the Medline and SPORT Discus databases, with all articles required to meet a specified criteria based on a quality review. Eighteen articles met the inclusion criteria, relating participant asymmetry scores to physical and sports performance measures. The findings of this systematic review indicate that inter-limb differences in strength may be detrimental to jumping, kicking and cycling performance. When inter-limb asymmetries are quantified during jumping based exercises, they have been primarily used to examine their association with change of direction speed with mixed findings. Inter-limb asymmetries have also been quantified in anthropometry, sprinting, dynamic balance and sport-specific actions, again with inconsistent findings. However, all results have been reported using associative analysis with physical or sport performance metrics with no randomised controlled trials included. Further research is warranted to understand the mechanisms that underpin inter-limb differences and the magnitude of performance changes that can be accounted for by these asymmetries.     

Effects of a minimalist shoe on running economy and 5-km running performance

The purpose of this study was to determine if minimalist shoes improve time trial performance of trained distance runners and if changes in running economy, shoe mass, stride length, stride rate and footfall pattern were related to any difference in performance. Twenty-six trained runners performed three 6-min sub-maximal treadmill runs at 11, 13 and 15 km·h^?1 in minimalist and conventional shoes while running economy, stride length, stride rate and footfall pattern were assessed. They then performed a 5-km time trial. In the minimalist shoe, runners completed the trial in less time (effect size 0.20 ± 0.12), were more economical during sub-maximal running (effect size 0.33 ± 0.14) and decreased stride length (effect size 0.22 ± 0.10) and increased stride rate (effect size 0.22 ± 0.11). All but one runner ran with a rearfoot footfall in the minimalist shoe. Improvements in time trial performance were associated with improvements in running economy at 15 km·h^?1 (r = 0.58), with 79% of the improved economy accounted for by reduced shoe mass (P < 0.05). The results suggest that running in minimalist shoes improves running economy and 5-km running performance.     

Effects of strategy use on children's motor performance in a continuous timing task

The purposes of this study were to associate age-related performance deficits in children with the use of recall strategies and to determine whether children who performed poorly in cycling would benefit from learning a recall strategy. In Experiment 1, 18 younger children (ages 5-7years) and 18 older children (ages 8-10 years) were asked to recall selected pedaling cadences. The majority of the older children used strategies and performed with less error than the younger children. In Experiment 2, children with a high number of errors in Experiment 1 were assigned to an experimental or a control group. The children in the experimental group were taught to use a specific recall strategy. The results showed that children who received the instruction in strategy use improved their performance.     

Effects of high-intensity interval training on canoeing performance

The purpose of this study was to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) utilizing a canoeing ergometer on endurance determinants, as well as aerobic and anaerobic performances among flat-water canoeists. Fourteen well-trained male flat-water canoeists were divided into an HIIT group or an MICT group. All subjects performed a continuous graded exercise test (GXT) and three fixed-distance (200, 500, and 1000?m) performance tests on a canoeing ergometer to determine canoeing economy, peak oxygen uptake (VO₂peak), and power at VO₂peak, and to calculate the critical velocity (CV) and anaerobic work capacity before and after the training programmes. The training programme involved training on a canoeing ergometer three times per week for four weeks. HIIT consisted of seven 2 min canoeing bouts at an intensity of 90% VO₂peak separated by 1 min of rest. The MICT group was trained at an intensity of 65% VO₂peak continuously for 20 min. After four weeks of training, performance in the 200-m distance test and the power at VO₂peak significantly improved in the HIIT group; performance in the 500?m and 1000?m distances and CV significantly improved in the MICT group. However, all variables were not significantly different between groups. It is concluded that HIIT for four weeks is an effective training strategy for improvement of short-distance canoeing performance. In contrast, MICT improves middle-distance canoeing performances and aerobic capacity.     

Effects of increased participation on veteran running performance

Contrary to elite performance that is approaching an asymptote, recent analyses suggested a trend for improvement in veterans. This might be attributable to a disproportionate increase in older age-group participation. We extracted 26 years (1987–2012) of men’s results of a running event in Switzerland, “La Course de l’Escalade” (7.25 km). We investigated trends in performance by five-year age-groups, taking the 10, 20, 30, and 50 fastest in each group, and then the 1^st, 5^th, and 10^th percentiles. Taking the 10, 20, 30 or 50 fastest runners there was a trend for improvement ranging from 0.07 to 0.22 min·year^?1 (p < .0001; 95% CI ?0.083 to ?0.049 and p < .0001; 95% CI ?0.250 to ?0.196 respectively) in the elder age-groups. Taking the 1^st, 5^th, and 10^th percentiles there were no trends for improvement, and actual deteriorations up to 0.13 (p < .0001; 95% CI +0.119 to +0.138) min·year^?1. Mixed-effect models with repeated measures for runners, confirmed a global deteriorating trend with an estimate of +0.11 min·year^?1 (p < .0001; 95% CI +0.107 to +0.116). The results suggest that increases in performance in older runners arise from modifications of sampling from a growing population.     

Effects of a motivational climate inntervention for coaches on young athletes' sport performance anxiety

The mastery approach to coaching is a cognitive-behavioral intervention designed to promote a mastery-involving motivational climate, shown in previous research to be related to lower anxiety in athletes. We tested the effects of this intervention on motivational climate and on changes in male and female athletes'cognitive and somatic performance anxiety over the course of a basketball season. Hierarchical linear modeling analyses revealed that the athletes in the intervention condition perceived their coaches as being more mastery-involving on the Motivational Climate Scale for Youth Sports when compared to athletes in an untreated control condition. Relative to athletes who played for untrained coaches, those who played for the trained coaches exhibited decreases on all subscales of the Sport Anxiety Scale-2 and on total anxiety score from preseason to late season. Control group athletes reported increases in anxiety over the season. The intervention had equally positive effects on boys and girls teams.     

Effects of various concentrations of carbohydrate mouth rinse on cycling performance in a fed state

The objective of this study was to identify the effects of mouth rinsing with a 6% and 16% carbohydrate solution (CHO) on time trial performance when compared to a 0% control (PLA) when in a fed state. Twelve recreationally active males underwent three trials by which they had to complete a set workload (600?±?65?W) in a fed state. Throughout each trial, participants rinsed their mouths with a 25?ml bolus of a 0% PLA, 6% or 16% CHO (maltodextrin) for every 12.5% of work completed. Rating of perceived exertion (RPE) and heart rate were recorded every 12.5% of total work. Performance times and power output improved significantly when using the 6% and 16% CHO versus the PLA trial (6% versus PLA, p?=?.002 and 16% versus PLA, p?=?.001). When comparing the performance times of the 6% to 16% CHO, no significance was observed (p?=?.244). There was no significant difference between heart rate levels or RPE values across the three trials. In conclusion, mouth rinsing with a 6% or 16% CHO solution has a positive effect on a cycling time trial performance undertaken in a fed state.     

Effects of a power-focussed resistance training intervention on backward grinding performance in America's Cup sailing

This study determined whether backward grinding performance in America's Cup sailing could be improved using a training intervention to increase power capability in the upper-body pull movement. Fourteen elite male sailors (34.9 ± 5.9 years; 98.1 ± 14.4 kg; 186.6 ± 7.7 cm) were allocated into experimental (speed-focussed) and control groups. Grinding performance was assessed using a grinding ergometer and an instrumented Smith machine measured force, velocity and power during the bench pull exercise. Conventional training produced significant improvements in bench pull 1 RM (5.2 ± 4.0%; p = 0.016) and maximum force production (5.4 ± 4.0%; p = 0.014). Speed-focussed training improved maximum power (7.8 ± 4.9%; p = 0.009), power at 1RM (10.3 ± 8.9%; p = 0.019) and maximum velocity (8.4 ± 2.6%; p = 0.0002). Backward grinding performance showed greater improvements in the experimental group than the control group for moderate (+1.8%) and heavy load (+6.0%) grinding. Changes in maximum power output and power at 1 RM had large correlations (r = 0.56–0.61) with changes in both moderate and heavy load grinding performance. Time to peak force had the strongest relationship, explaining 70% of the change in heavy load grinding performance. Although the performance benefit was not entirely clear the likelihood of a detrimental effect was low ( < 5%) and therefore implementation could be recommended.     

Effects of a carbohydrate and caffeine gel on intermittent sprint performance in recreationally trained males

Abstract

We investigated the effects of ingesting carbohydrate gels with and without caffeine on a ~90-minute, four blocks intermittent sprint test (IST), in 12 recreationally trained male athletes. Using a cross-over design, one 70 ml dose of gel containing either 25 g of carbohydrate with (CHOCAF) or without (CHO) 100 mg of caffeine, or a non-caloric placebo (PL) was ingested on three occasions: one hour before, immediately prior to and during the IST. Blood glucose, rating of perceived exertion (RPE) and fatigue index (FI) were analysed. Glucose showed significantly higher values for both CHOCAF and CHO at the first (p=0.005 and p=0.000, respectively), second (p=0.009 and 0.008, respectively) and third (p=0.003 and 0.001, respectively) blocks when compared with PL, while only CHOCAF was significantly different to PL (p=0.002) at the fourth block. CHOCAF showed an improved FI (mean 5.0, s =1.7) compared with CHO (mean 7.6, s =2.6; p=0.006) and PL (mean 7.4, s =2.4; p=0.005), a significantly lower RPE (mean 14.2, s =2) compared with PL (mean 15.3, s =2; p=0.003) and a trend in respect of CHO (mean 14.9, s =2.3; p=0.056) after the third block. In conclusion, ingesting CHOCAF one hour before, prior to and during an IST is effective at transiently reducing fatigue and RPE whilst maintaining higher glucose levels at the final stages of the exercise.