Description:
Agility is an important component of many sports but has not been extensively researched. The various components that contribute to agility performance are discussed and training guidelines are provided. There appears to be limited transfer to agility performance from straight sprint training as well as from general strength training. The principle of training specificity is emphasized to achieve maximum transfer to on-field performance.
Description:
Agility is an important component of many sports but has not been extensively researched. The various components that contribute to agility performance are discussed and training guidelines are provided. There appears to be limited transfer to agility performance from straight sprint training as well as from general strength training. The principle of training specificity is emphasized to achieve maximum transfer to on-field performance.
Description:
At present, no agreement on a precise definition of agility within the sports science community exists. The term is applied to a broad range of sport contexts, but with such great inconsistency, it further complicates our understanding of what trainable components may enhance agility. A new definition of agility is proposed: "a rapid whole-body movement with change of velocity or direction in response to a stimulus". Agility has relationships with trainable physical qualities such as strength, power and technique, as well as cognitive components such as visual-scanning techniques, visual-scanning speed and anticipation. Agility testing is generally confined to tests of physical components such as change of direction speed, or cognitive components such as anticipation and pattern recognition. New tests of agility that combine physical and cognitive measures are encouraged.
Description:
At present, no agreement on a precise definition of agility within the sports science community exists. The term is applied to a broad range of sport contexts, but with such great inconsistency, it further complicates our understanding of what trainable components may enhance agility. A new definition of agility is proposed: "a rapid whole-body movement with change of velocity or direction in response to a stimulus". Agility has relationships with trainable physical qualities such as strength, power and technique, as well as cognitive components such as visual-scanning techniques, visual-scanning speed and anticipation. Agility testing is generally confined to tests of physical components such as change of direction speed, or cognitive components such as anticipation and pattern recognition. New tests of agility that combine physical and cognitive measures are encouraged.
Description:
The purposes of this review are to identify the factors that contribute to the transference of strength and power training to sports performance and to provide resistance-training guidelines. Using sprinting performance as an example, exercises involving bilateral contractions of the leg muscles resulting in vertical movement, such as squats and jump squats, have minimal transfer to performance. However, plyometric training, including unilateral exercises and horizontal movement of the whole body, elicits significant increases in sprint acceleration performance, thus highlighting the importance of movement pattern and contraction velocity specificity. Relatively large gains in power output in nonspecific movements (intramuscular coordination) can be accompanied by small changes in sprint performance. Research on neural adaptations to resistance training indicates that intermuscular coordination is an important component in achieving transfer to sports skills. Although the specificity of resistance training is important, general strength training is potentially useful for the purposes of increasing body mass, decreasing the risk of soft-tissue injuries, and developing core stability. Hypertrophy and general power exercises can enhance sports performance, but optimal transfer from training also requires a specific exercise program.
Description:
The purposes of this review are to identify the factors that contribute to the transference of strength and power training to sports performance and to provide resistance-training guidelines. Using sprinting performance as an example, exercises involving bilateral contractions of the leg muscles resulting in vertical movement, such as squats and jump squats, have minimal transfer to performance. However, plyometric training, including unilateral exercises and horizontal movement of the whole body, elicits significant increases in sprint acceleration performance, thus highlighting the importance of movement pattern and contraction velocity specificity. Relatively large gains in power output in nonspecific movements (intramuscular coordination) can be accompanied by small changes in sprint performance. Research on neural adaptations to resistance training indicates that intermuscular coordination is an important component in achieving transfer to sports skills. Although the specificity of resistance training is important, general strength training is potentially useful for the purposes of increasing body mass, decreasing the risk of soft-tissue injuries, and developing core stability. Hypertrophy and general power exercises can enhance sports performance, but optimal transfer from training also requires a specific exercise program.
Description:
A purpose of this study was to determine if pre-season anthropometric and physiological measures were significantly different for the players from one Australian Football League (AFL) club selected to play in the first game of the season compared to the players not selected. Another purpose was to compare fitness test results for defenders, forwards and mid-fielders in the same AFL club. Thirty-four players were tested for isolated quadriceps and hamstrings strength, leg extensor muscle strength and power, upper body strength, sprinting speed, vertical jump (VJ), endurance, skinfolds and hamstring flexibility. The starters who were selected to play the first game were a significantly older and more experienced playing group, and were significantly better (p < 0.05) in measures of leg power, sprinting speed and the distance covered in the Yo Yo intermittent recovery test compared to the non-starters. Although there were trends for the superiority of the starters, the differences in lower and upper body strength, VJ and predicted VO(2)max were nonsignificant. The forwards generally produced the worst fitness scores of the playing positions with the midfielders having significantly lower skinfolds and the defenders possessing better hamstring strength and VJ compared to the forwards. It was concluded that some fitness qualities can differentiate between starters and non-starters, at least in one AFL club. Comparisons of playing positions and the development of fitness norms for AFL players require further research.
Description:
A purpose of this study was to determine if pre-season anthropometric and physiological measures were significantly different for the players from one Australian Football League (AFL) club selected to play in the first game of the season compared to the players not selected. Another purpose was to compare fitness test results for defenders, forwards and mid-fielders in the same AFL club. Thirty-four players were tested for isolated quadriceps and hamstrings strength, leg extensor muscle strength and power, upper body strength, sprinting speed, vertical jump (VJ), endurance, skinfolds and hamstring flexibility. The starters who were selected to play the first game were a significantly older and more experienced playing group, and were significantly better (p < 0.05) in measures of leg power, sprinting speed and the distance covered in the Yo Yo intermittent recovery test compared to the non-starters. Although there were trends for the superiority of the starters, the differences in lower and upper body strength, VJ and predicted VO(2)max were nonsignificant. The forwards generally produced the worst fitness scores of the playing positions with the midfielders having significantly lower skinfolds and the defenders possessing better hamstring strength and VJ compared to the forwards. It was concluded that some fitness qualities can differentiate between starters and non-starters, at least in one AFL club. Comparisons of playing positions and the development of fitness norms for AFL players require further research.
Description:
The purpose of this research was to determine the effect of static stretching in a warm-up on hip flexor and quadriceps flexibility as measured by a modified Thomas test and on range of motion (ROM) of the leg and foot speed at impact in kicking a football with maximum effort. Sixteen Australian Rules (AR) footballers performed two different warm-ups on different days. One warm-up involved five minutes of sub-maximum running followed by seven practice kicks, while the other also included 4.5 minutes static stretching of the hip flexors and quadriceps after the running. A modified Thomas test was conduced before and after each warm-up. Players performed maximum effort drop punt kicks into a net while being videotaped to determine the ROM of the kicking leg and foot speed at impact with the ball. There were no significant changes in flexibility (p>0.05) as a result of either warm-up and there were no significant differences between the warm-ups in the kicking variables (p>0.05). It was concluded that the Thomas test may not have been sensitive to possible acute changes in flexibility from the warm-ups, and that stretching had no influence on kicking ROM or foot speed, possibly because of the complexity of the kicking skill.
Description:
The purpose of this research was to determine the effect of static stretching in a warm-up on hip flexor and quadriceps flexibility as measured by a modified Thomas test and on range of motion (ROM) of the leg and foot speed at impact in kicking a football with maximum effort. Sixteen Australian Rules (AR) footballers performed two different warm-ups on different days. One warm-up involved five minutes of sub-maximum running followed by seven practice kicks, while the other also included 4.5 minutes static stretching of the hip flexors and quadriceps after the running. A modified Thomas test was conduced before and after each warm-up. Players performed maximum effort drop punt kicks into a net while being videotaped to determine the ROM of the kicking leg and foot speed at impact with the ball. There were no significant changes in flexibility (p>0.05) as a result of either warm-up and there were no significant differences between the warm-ups in the kicking variables (p>0.05). It was concluded that the Thomas test may not have been sensitive to possible acute changes in flexibility from the warm-ups, and that stretching had no influence on kicking ROM or foot speed, possibly because of the complexity of the kicking skill.
Description:
The objective of this study was to investigate whether a warm-up consisting of a series of maximal contractions would augment the force and activation of subsequent leg extensor contractions. Both voluntary and evoked isometric contractions were tested to determine the mechanisms underlying the response. Nine subjects were tested for twitch, tetanic, submaximal (30%), and maximal voluntary contractile (MVC) properties before and after (1, 5, 10, and 15 minutes) one to three 10-second MVCs. MVC force either did not change following 1-2 MVCs or was depressed at 10 and 15 minutes after 3 MVCs. MVC activation was decreased (4.4-6.9%) throughout recovery, whereas submaximal contractions were minimally affected. Although overall, twitches were potentiated (15.5-19.8%) posttest, 3 MVCs had significantly greater twitch potentiation than 1 or 2 MVCs at 5 and 10 minutes. Results suggest that voluntary and evoked contractions respond differently to prior 10-second MVCs. In the present study, a warm-up routine of 1-3 MVCs of a 10-second duration did not enhance subsequent voluntary performance.
Description:
The objective of this study was to investigate whether a warm-up consisting of a series of maximal contractions would augment the force and activation of subsequent leg extensor contractions. Both voluntary and evoked isometric contractions were tested to determine the mechanisms underlying the response. Nine subjects were tested for twitch, tetanic, submaximal (30%), and maximal voluntary contractile (MVC) properties before and after (1, 5, 10, and 15 minutes) one to three 10-second MVCs. MVC force either did not change following 1-2 MVCs or was depressed at 10 and 15 minutes after 3 MVCs. MVC activation was decreased (4.4-6.9%) throughout recovery, whereas submaximal contractions were minimally affected. Although overall, twitches were potentiated (15.5-19.8%) posttest, 3 MVCs had significantly greater twitch potentiation than 1 or 2 MVCs at 5 and 10 minutes. Results suggest that voluntary and evoked contractions respond differently to prior 10-second MVCs. In the present study, a warm-up routine of 1-3 MVCs of a 10-second duration did not enhance subsequent voluntary performance.
Description:
Context: Flexibility tests are sometimes thought to be related to range of motion in dynamic activities, but such a relationship remains to be determined. Objective: To determine the correlation between flexibility and hip and knee angles in Australian football kicking. Design: Correlation. Setting: Biomechanics laboratory. Participants: 16 Australian Rules football players. Main Outcome Measures: Hip and knee angles of the preferred kicking leg in a relaxed position were determined with a modified Thomas test. Maximum hip extension, the knee-flexion angle in this position, the maximum knee-flexion angle, and the hip angle at this position during the swing phase of maximum-effort drop-punt kicks were determined. Results: Significant correlations were found between hip flexibility and maximum hip extension (r =.65, P < .01) and hip angle at the maximum knee-flexion angle (r = .70, P < .01). Conclusions: The data indicate a moderate association between hip flexibility and hip angles during kicking.
Description:
Context: Flexibility tests are sometimes thought to be related to range of motion in dynamic activities, but such a relationship remains to be determined. Objective: To determine the correlation between flexibility and hip and knee angles in Australian football kicking. Design: Correlation. Setting: Biomechanics laboratory. Participants: 16 Australian Rules football players. Main Outcome Measures: Hip and knee angles of the preferred kicking leg in a relaxed position were determined with a modified Thomas test. Maximum hip extension, the knee-flexion angle in this position, the maximum knee-flexion angle, and the hip angle at this position during the swing phase of maximum-effort drop-punt kicks were determined. Results: Significant correlations were found between hip flexibility and maximum hip extension (r =.65, P < .01) and hip angle at the maximum knee-flexion angle (r = .70, P < .01). Conclusions: The data indicate a moderate association between hip flexibility and hip angles during kicking.
Description:
The purpose of this study was to determine if straight sprint training transferred to agility performance tests that involved various change-of-direction complexities and if agility training transferred to straight sprinting speed. Thirty-six males were tested on a 30-m straight sprint and 6 agility tests with 2-5 changes of direction at various angles. The subjects participated in 2 training sessions per week for 6 weeks using 20-40-m straight sprints (speed) or 20-40-m change-of-direction sprints (3-5 changes of 100°) (agility). After the training period, the subjects were retested, and the speed training resulted in significant improvements (p < 0.05) in straight sprinting speed but limited gains in the agility tests. Generally, the more complex the agility task, the less the transfer from the speed training to the agility task. Conversely, the agility training resulted in significant improvements in the change-of-direction tests (p < 0.05) but no significant improvement (p > 0.05) in straight sprint performance. We concluded that straight speed and agility training methods are specific and produce limited transfer to the other. These findings have implications for the design of speed and agility training and testing protocols.
Description:
The purpose of this study was to determine if straight sprint training transferred to agility performance tests that involved various change-of-direction complexities and if agility training transferred to straight sprinting speed. Thirty-six males were tested on a 30-m straight sprint and 6 agility tests with 2-5 changes of direction at various angles. The subjects participated in 2 training sessions per week for 6 weeks using 20-40-m straight sprints (speed) or 20-40-m change-of-direction sprints (3-5 changes of 100°) (agility). After the training period, the subjects were retested, and the speed training resulted in significant improvements (p < 0.05) in straight sprinting speed but limited gains in the agility tests. Generally, the more complex the agility task, the less the transfer from the speed training to the agility task. Conversely, the agility training resulted in significant improvements in the change-of-direction tests (p < 0.05) but no significant improvement (p > 0.05) in straight sprint performance. We concluded that straight speed and agility training methods are specific and produce limited transfer to the other. These findings have implications for the design of speed and agility training and testing protocols.
Description:
A speed program was developed for two male sixteen-year-old Australian Rules footballers who play state level competition. The program targeted acceleration, repeat sprint ability (RSA), and agility, and was performed two days per week on a natural grass oval. Examples of activities are provided for each speed quality. A key activity for acceleration was resisted sprinting involving towing a sled, which encouraged the desired body positions and technique. Repeat sprint ability was developed by prescribing activities containing short sprints with minimal recovery periods. Agility techniques were initially introduced, and then training activities included evasive changes of direction in an attacking role, and also defensive manoeuvres in one-on-one scenarios. A central principle in the creation of training activities was to contextualise them to Australian Rules football, with the intention of maximising transfer to on-field performance. This involved stressing maximum efforts with sound sprint technique under various imposed perturbations, such as the execution of football skills, pressure from an opponent, and fatigue.
Description:
The purpose of this research was to determine 1) the relationship between lower-body strength qualities and baserunning and 2) the relationship between lower-body strength qualities and the time discrepancy between baserunning and linear sprints of the same distance. Twenty-one male baseball players (age: 17 ± 1.11 years; height: 179.5 ± 6.73 cm; body mass: 82.48 ± 11.1 kg) from a State Baseball Academy were tested for peak force (PF) production in an isometric mid-thigh pull (IMTP), peak power (PP) and jump height (HCMJ) in a countermovement jump (CMJ), and reactive strength index (RSI) from a drop jump (DJ). Additionally, they performed sprints from Homeplate to Second Base (54.8mBR) and over a 54.8m linear distance (54.8mLIN), with splits taken at 10m (10mBR, 10mLIN) and 27.4m (27.4mBR, 27.4mLIN). Relationships between all the collected variables plus the difference between 54.8mBR and 54.8mLIN (BRD), relative PF (RelPF) and relative PP (RelPP) were assessed by Pearson product-moment correlation coefficient. Only ten complete sets of data were collected (age: 16.9 ± 1.29 years; height: 180.2 ± 7.07 cm; body mass: 84.67 ± 12.1 kg). RelPF (r = -0.81, p