The purpose of this study was to compare the benefits of 4-weeks of velocity-based training (VBT) using different augmented feedback (AugFb) types and the frequency of AugFb, and whether adaptations are retained 10 days post-training. Thirty-seven collegiate male rugby players were divided into groups that received immediate-feedback (ImFb; n=9), visual-feedback (ViFb; n=10), average-feedback (AvgFb; n=10) and no-feedback (NoFb; n=8) during each VBT session consisting of 3 sets of 5 repetitions of loaded jump squats. The ImFb group received AugFb regarding lifting velocity under loaded jump squats (LV-JS) following every jump, whereas LV-JS measures were averaged following each set of jumps and presented to the AvgFb group. The loaded jump squats were video-recorded and displayed as kinematic feedback for the ViFb group following each set, although no feedback was provided for the NoFb group. LV-JS measures were reported at baseline, during each training session and 10-days post training. LV-JS measures were significantly greater for the ImFb Group compared to the other groups during a number of post-baseline time points (P<0.05). Furthermore, at 4-weeks of VBT and 10 days post-retention, effect size (ES) calculations showed that LV-JS measures were greater with moderate to large effects for the ImFb group compared to the NoFb (ES=1.02-1.25), AvgFb (ES=0.78-0.82) and ViFb (ES=0.74-1.60), respectively. However, LV-JS measures were reduced with moderate to large effects 10 days post-retention for the ViFb (ES=-0.60) and NoFb (ES=-0.85) groups. Providing LV-JS feedback following each jump appears to optimize performance and should be considered as a training tool during VBT.

Physical characteristics and performance of Japanese top-level American football players. J Strength Cond Res 31(9): 2455-2461, 2017-This study aimed to compare the physical characteristics and performance between top-level nonprofessional football players in Japan and National Football League (NFL) Combine invited players and between top-level and middle-level players in Japan to determine the factors that enhance performance in international and national competitions. A total of 168 American football players (.20 years) in Japan participated in an anthropometric (height and weight) and physical (vertical jump, long jump, 40-yard dash, pro-agility shuttle, 3-cone drill, and bench press repetition test) measurement program based on the NFL Combine program to compete in the selection of candidates for the Senior World Championship. All players were categorized into 1 of the 3 position groups based on playing position: skill players, big skill players, and linemen. Japanese players were additionally categorized into selected and nonselected players for the second tryout. The NFL Combine candidates had significantly better performance than selected Japanese players on all variables except on performance related to quickness among the 3 position groups. Compared with nonselected players, selected Japanese skill players had better performance in the 40-yard dash and bench press test and big skill players had better performance in the vertical jump, broad jump, and 40-yard dash. Selected and nonselected Japanese linemen were not different in any measurements. These results showed the challenges in American football in Japan, which include not only improving physical performance of top-level players, but also increasing the number of football players with good physical performance.

The purpose of the present study was to examine the timing for the detection of relevant information in the final running direction of attackers' cutting manoeuvres. Skilled basketball players and novices performed sidestep and reach tasks in response to a ready-go choice stimuli using light-emitting diode (LED) task and video stimuli (video task) wherein skilled ball players executed cutting manoeuvres. The time at which the defenders first obtained relevant visual information was estimated by subtracting the visuo-motor processing time, acquired from the reaction time in the LED task, from the reaction time in the video task. Skilled basketball players reacted to and reached towards the target faster than novices, whereas the estimated video cue timings for the skilled players were not different from those for the novices. The results suggest that the anticipation of attacker's direction in this task would be a general visuo-motor skill, even without previous specialised perceptual training. Combined with the results from the reaction performance in the video task, we conclude that novices are afforded shorter times and more uncertain information before their stepping when they are in a one-on-one ballgame defensive scenario because their sidestepping takes a relatively long time.

The aim of the study was to examine the relationship between pitching ball velocity and segmental (trunk, upper arm, forearm, upper leg, and lower leg) and whole-body muscle volume (MV) in high school baseball pitchers. Forty-seven male high school pitchers (40 right-handers and seven left-handers; age, 16.2 ± 0.7 years; stature, 173.6 ± 4.9 cm; mass, 65.0 ± 6.8 kg, years of baseball experience, 7.5 ± 1.8 years; maximum pitching ball velocity, 119.0 ± 9.0 km/hour) participated in the study. Segmental and whole-body MV were measured using segmental bioelectrical impedance analysis. Maximum ball velocity was measured with a sports radar gun. The MV of the dominant arm was significantly larger than the MV of the non-dominant arm (P < 0.001). There was no difference in MV between the dominant and non-dominant legs. Whole-body MV was significantly correlated with ball velocity (r = 0.412, P < 0.01). Trunk MV was not correlated with ball velocity, but the MV for both lower legs, and the dominant upper leg, upper arm, and forearm were significantly correlated with ball velocity (P < 0.05). The results were not affected by age or years of baseball experience. Whole-body and segmental MV are associated with ball velocity in high school baseball pitchers. However, the contribution of the muscle mass on pitching ball velocity is limited, thus other fundamental factors (ie, pitching skill) are also important.