Purpose: The well-being of elite rugby union players has been intensely scrutinised in recent years. Understanding the longitudinal development of physical traits in junior players, alongside the moderating effect of simultaneous increases in body mass, can aid in improving programming and ultimately help junior players prepare for the demands of senior rugby. The purpose of this study was to investigate the longitudinal physical development of elite adolescent backs and forwards in a professional rugby union academy. Methods: A total of 15 players (age, 17.0 [0.2] y; body mass, 90 [14] kg; height, 183 [9] cm; n = 7 backs, n = 8 forwards) completed anthropometric measures and 3 primary performance assessments (countermovement jump, Yo-Yo intermittent recovery test level 1, and 10-m speed) at baseline, year 2, and year 3. Mixed modelling was used to assess player development over time and differences in this development by playing position. Magnitude-based inferencing was used to assess the uncertainty in the effects. Results: There was a substantial increase in countermovement jump height for both groups combined (0.9, ±0.4; standardized improvement, ±90% confidence limits; most likely substantial). Forwards exhibited a moderate-sized decrease in speed (−1.0, ±0.5; very likely substantial), and there was a large difference between groups with regards to speed change with backs outperforming forwards (1.5, ±0.9; very likely substantial). For forward, body mass change had a large negative association with 10-m speed (−1.9, ±0.7; most likely substantial) and Yo-Yo intermittent recovery test level 1 change (−1.2, ±0.9; very likely substantial). Conclusion: These findings provide novel normative data for longitudinal changes in junior rugby union players and suggest that coaches should account for changes in body mass when targeting increases in speed and aerobic fitness.

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The aims of this investigation were to describe the physical output of hockey relative to possession status, and to identify differences in physical output during each possession category with respect of match result. Ten international matches were analysed utilizing Sportscode to identify in and not in possession instances. 24 players (age 26 ± 4) wore a 10 Hz GPS device to track physical output. Linear Mixed Models and post hoc pairwise comparisons were utilised to compare the physical output in each possession category within each position and relative to match result. Significant main effects were found for possession status on several physical output metrics (p ≤ 0.05). For all positions except forwards, not in possession instances were more physically demanding than in possession instances for metrics such as relative total distance, explosive distance, and high-speed running (>5.5 m.s−1). No significant difference was identified between possession category physical output aligned with match result (p > 0.05). This study shows for the first time that not in possession instances were more physically demanding than in possession instances for defenders, outside backs and midfielders. For not in possession instances, relative total distance and high-speed running was, on average, 13% and 41% higher compared to in possession instances. Furthermore, there was no statistical difference in physical output for any position during each possession category relative to the match result.

This study examined trunk muscle activation, balance and proprioception while squatting with a water-filled training tube (WT) and a traditional barbell (BB), with either closed (CE) or open eyes (OE). Eighteen male elite Gaelic footballers performed an isometric squat under the following conditions: BB-OE, BB-CE, WT-OE and WT-CE. The activity of rectus abdominis (RA), external oblique (EO) and multifidus (MF) was measured using electromyography, along with sway of the centre of pressure (CoP) using a force platform. Only the EO and the MF muscles exhibited an increased activity with WT (p < 0.01). In the medio-lateral direction both the velocity and range of the CoP increased significantly with WT (p < 0.01). Interestingly, the range of the CoP for the WT-CE condition was significantly lower than WT-OE (p < 0.05, d = 0.44), whilst the velocity of the CoP was marginally reduced (d = 0.29). WT elicited a greater level core muscle activation and created a greater challenge to postural stability when compared to a BB. It appears that WT does not benefit from vision but emphasises the somatosensory control of balance. The use of WT may be beneficial in those sports requiring development of somatosensory/proprioceptive contribution to balance control.

This investigation aimed to compare the international level peak intensity period of male field hockey players to those experienced during professional and amateur club hockey match play. Twenty-seven players from an international squad were monitored for all activity relating to field hockey over three seasons. The peak intensity period, of 3 min duration, was extracted from match play files for international and club matches. Club matches were categorised by league standard—professional vs. amateur. The output for the peak intensity period, within positions, was compared using linear mixed models (LMMs) and post hoc pairwise comparisons. Significance levels were set as p < 0.05 and Cohen’s d was utilised for effect sizes. Competition level had a main effect on relative total distance (p < 0.05) and significant interaction effects were found between competition level and position (p < 0.05). Midfielders competing in amateur leagues and international match play completed less relative total distance than those who compete in professional leagues (−47.88 m/min, p < 0.05), (−46.06 m/min, p < 0.05) with large effect sizes reported. No other position displayed significant differences for peak periods. Match play in professional leagues provide opportunities for midfielders to experience peak intensity periods of a greater magnitude than international match play.