The purpose of this study was to determine the relationships between selected physical qualities, change-of-direction (COD) speed, and defensive agility performance in Australian Rules football players. Twenty-four male community-level players were assessed on sprint acceleration (10-m time), maximum strength (3 repetition-maximum half squat), leg power (countermovement jump), reactive strength (drop jump), and a single COD speed test and a defensive agility test. Change-of-direction speed was correlated with reactive strength (r = -0.645, p = 0.001) and sprint acceleration (r = 0.510, p = 0.011). Multiple regression indicated that the combined physical qualities explained 56.7% of the variance associated with COD speed (adjusted R = 0.567, p ≤ 0.05). Participants were median split into faster and slower COD speed groups, and these were compared by independent t-tests. The faster group was significantly better (p ≤ 0.05) on the sprint acceleration and reactive strength tests (large effect size). The correlations between physical qualities and agility were trivial to small (r = -0.101 to 0.123, p > 0.05) and collectively explained only 14.2% of the variance associated with agility performance (adjusted R = -0.142, p > 0.05). When faster and slower agility groups were compared, there were trivial to moderate differences (p > 0.05) in all physical qualities. It was concluded that reactive strength and sprint acceleration are important for COD speed, but the physical qualities assessed are not associated with defensive agility performance. For agility tasks similar to those in this study, sprint and resistance training should not be emphasized, and training other factors, such as the development of sport-specific technique and cognitive skill, is recommended.

BACKGROUNDː Hamstring Strain Injuries (HSI) are among the most common injuries in field based team sports with a high speed running component. The implementation of the Nordic Hamstring Exercise (NHE) is a well documented method of improving eccentric hamstring strength to mitigate the risk of HSI occurance. Sprint training is specific to the injury mechanism and is thought to activate the hamstrings through maximal eccentric contractions. The purpose of this study was to compare the effects of sprint training and the NHE on eccentric hamstring strength and sprint performance. METHODSː Twenty-eight participants (Mean ± SD age = 16.21 ± 1.34 years; height = 1.75m ± 0.10m; body mass = 68.5kg ± 12.1kg) completed an eccentric hamstring strength assessment and 40m sprint to assess acceleration and maximum speed. Participants were randomly allocated to either a NHE training or sprint training group. Two sessions per week for four-weeks of training was performed with baseline testing procedures repeated in the week following the intervention. Perceptions of soreness were recorded following the warmup in each training session. RESULTSː Both the NHE (effect size = 0.39, p < 0.05) and sprint training (effect size = 0.29, p <0.05) groups displayed significant gains in eccentric hamstring strength. The NHE group reported trivial improvements in sprint performance, whilst the sprint training group experienced a moderate improvement, specifically in maximum speed (ES = 0.83 Moderate). Sprint training also produced greater perceptions of soreness than the NHE following a fourweek training intervention, specifically before the start of the last session (p < 0.05). CONCLUSIONSː These findings indicate that sprint training had a beneficial effect for both eccentric hamstring strength and sprint performance, whilst also producing greater soreness than the NHE following the final training session. It was concluded that a fourweek block of maximum speed training may have both an injury prevention and performance enhancement benefit.

There is currently a lack of consensus in the collection of injury/illness data, limiting the development of prevention programmes for combat sport as a whole. However, sport-specific data that identify body areas with high injury frequency can provide direction to clinicians, enabling them to focus their attention on developing pathologies in these areas. In doing so, clinicians can enhance the practical elements of their role within the integrated combat sport performance team and assist in the regular update of surveillance records.

Rowing requires strength, power, and strength-endurance for optimal performance. A rowing-based warm-up could be enhanced by exploiting the postactivation potentiation (PAP) phenomenon, acutely enhancing power output at the beginning of a race where it is needed most. Minimal research has investigated the effects of PAP on events of longer duration (i.e. 1,000-m rowing). The purpose of this research was to investigate the effects of PAP on 1,000-m rowing ergometer performance through the use of 2 different warm-up procedures: (a) a rowing warm-up combined with a series of isometric conditioning contractions, known as the potentiated warm-up (PW), and (b) a rowing warm-up only (NW). The isometric conditioning contractions in the PW were performed by "pulling" an immovable handle on the rowing ergometer, consisting of 5 sets of 5 seconds (2 seconds at submaximal intensity, and 3 seconds at maximal intensity), with a 15-second recovery between sets. The 1,000-m rowing ergometer time trial was performed after each warm-up condition, whereby mean power output, mean stroke rate, and split time were assessed every 100 m. Ten Australian national level rowers served as the subjects and performed both conditions in a counterbalanced order on separate days. The PW reduced 1,000-m time by 0.8% (p > 0.05). The PW improved mean power output by 6.6% (p < 0.01) and mean stroke rate by 5.2% (p < 0.01) over the first 500 m; resulting in a reduction of 500-m time by 1.9% (p < 0.01), compared with the NW. It appears that the inclusion of isometric conditioning contractions to the rowing warm-up enhance short-term rowing ergometer performance (especially at the start of a race) to a greater extent than a rowing warm-up alone.