Brian S. Green

Physical Game Demands in Elite Rugby Union: A Global Positioning System Analysis and Possible Implications for Rehabilitation

STUDY DESIGN Descriptive. OBJECTIVES To evaluate the physical demands of an international Rugby Union-level game using a global positioning system (GPS). BACKGROUND Elite Rugby Union teams currently employ the latest technology to monitor and evaluate physical demands of training and games on their players. METHODS GPS data from 2 players, a back and a forward, were collected during an international Rugby Union game. Locomotion speed, total body load, and body load sustained in tackles and scrums were analyzed. RESULTS Players completed an average distance of 6715 m and spent the major portion of the game standing or walking, interspersed with medium- and high-intensity running activities. The back performed a higher number of high-intensity sprints and reached a greater maximal speed. Body load data revealed that high levels of gravitational force are sustained in tackling and scrum tasks. CONCLUSION The current study provides a detailed GPS analysis of the physical demands of international Rugby Union players. These data, when combined with game video footage, may assist sports medicine professionals in understanding the demands of the game and mechanism of injury, as well as improving injury rehabilitation.

A Valid Field Test Protocol of Linear Speed and Agility in Rugby Union

Green, BS, Blake C, and Caulfield, BM. A valid field test protocol of linear speed and agility in rugby union. J Strength Cond Res 25(5): 1256-1262, 2011-Field testing is a key component to measure player performance in all sports, which provides coaches and strength and conditioning staff information to evaluate player performance and measure desired training effects. Therefore, the purpose of this study was to investigate the reliability and construct validity of a rugby union field test protocol based on analysis of the components of the game. Participants were placed in an Academy (n = 17) or Club (n = 11) group determined by current playing level. Trials of 10- and 30-m linear speed (LS), change of direction speed, and reactive agility speed were measured to evaluate the field test protocols utility in distinguishing players of different playing abilities. Reliability analysis of each field test demonstrated stable values allowing this field test protocol to be used to compare between groups. Furthermore, the Academy players performed significantly (p < 0.05) faster compared to Club players in all LS and agility components. These results suggest that this field test protocol is appropriate to identify rugby union players of varying playing abilities allowing coaches and strength and fitness staff to measure a players capability to execute critical aspects of the game and may have application in performance evaluation and talent identification. The results from this study suggest that this test battery is an appropriate measure in identifying the varying playing abilities of rugby union players. This enables coaches and fitness staff to assess a players capability in executing critical aspects of the game and also may have application in performance evaluation and talent identification.

The thigh adductor squeeze test: 45° of hip flexion as the optimal test position for eliciting adductor muscle activity and maximum pressure values.

The thigh adductor squeeze test is commonly used in the diagnosis of groin injuries. Currently no reports exist in the published literature which, detail the level of activation of the adductor musculature during the test as well as concomitant pressure values. Thus the aim of the present study was to investigate adductor muscle activity and concomitant pressure values during the performance of the thigh adductor squeeze test at 0°, 45°, and 90° of hip flexion. Eighteen Gaelic games athletes without any history of groin injury participated. Each participant performed 3 repetitions of the thigh adductor squeeze test in the three positions of 0°, 45°, and 90° of hip flexion. Adductor musculature surface electromyographic activity (bilateral) and pressure values quantified using a commercially available sphygmomanometer were recorded for each test. The greatest pressure values were observed in the 45° of hip flexion test position (0°: 202.50 ± 57.28 mmHg; 45°: 236.76 ± 47.29 mmHg; 90°: 186.11 ± 44.01 mmHg; P < 0.05). Similarly, the greatest amount of adductor muscle activity was observed in the 45° of hip flexion test position (P < 0.05). The combined results of the present study suggest that the 45° of hip flexion test position is the optimal thigh adductor squeeze test position for eliciting adductor muscle activity and maximum pressure values.

Intrarater Reliability of the Adductor Squeeze Test in Gaelic Games Athletes

CONTEXT Groin pain is commonly experienced by athletes involved in field-based sports and is particularly prevalent in Gaelic Games athletes. The adductor squeeze test is commonly used in the assessment of groin pain and injuries. To date, no evidence in the literature provides the reliability of the adductor squeeze test using a sphygmomanometer in assessing the adductor muscle integrity of Gaelic Games athletes. Given the high proportion of groin pain encountered in Gaelic Games athletes, establishing the reliability of the adductor squeeze test will allow clinicians to monitor injury responses and to assess return-to-play criteria. OBJECTIVE To evaluate the intrarater reliability of a commercially available sphygmomanometer for measuring adductor squeeze values in Gaelic Games athletes and to determine if different squeeze values are associated with the 3 commonly used test positions. DESIGN Descriptive laboratory study. SETTING University clinical skills laboratory. PATIENTS OR OTHER PARTICIPANTS Eighteen male Gaelic Games athletes without any previous or current history of groin or pelvic pain. INTERVENTION(S) Each participant performed the adductor squeeze test in 3 positions of hip joint flexion (0°, 45°, and 90°) on 2 test days separated by at least 1 week. MAIN OUTCOME MEASURE(S) Adductor squeeze test values (mm Hg) quantified by a commercially available sphygmomanometer. RESULTS Intrarater reliability intraclass correlation values ranged from 0.89 to 0.92 (intraclass correlation coefficients were 0°, 0.89; 45°, 0.92; and 90°, 0.90). The highest squeeze values were recorded in the 45° of hip flexion test position, and these values differed from those demonstrated in the 0° and 90° hip flexion test positions (P < .05). CONCLUSIONS A commercially available sphygmomanometer is a reliable device for measuring adductor squeeze test values.

A comparison of cutting technique performance in rugby union players.

Green, BS, Blake, C, and Caulfield, BM. A comparison of cutting technique performance in rugby union players. J Strength Cond Res 25(10): 2668–2680, 2011—Rugby union is a dynamic running game requiring players to regularly perform change of direction maneuvers to avoid player opposition. The change of direction/cutting task is characterized by rapid deceleration onto the plant leg (PL) then reacceleration by the push-off leg (POL) into the new direction. Identification of the kinematic characteristics of cutting tasks and their relationship to playing ability may offer practical guidelines for coaches and strength and conditioning staff to design effective agility drills and provide player feedback to improve technique. Therefore, the purpose of this study was to investigate the kinematic and temporal characteristics of cutting tasks and their relationship to performance in rugby union players. Semiprofessional rugby union players from the All-Ireland League were placed in a Starters (N = 13) or Nonstarters (N = 10) group based on whether they were routinely selected in the starting team or were reserve ‘bench’ players. Each participant was fitted with reflective markers and performed 10 cutting trials (5 left, 5 right) of a single 45° cutting task to collect relevant kinematic data. The directions of the cutting trials were classified as a dominant or nondominant cut based on the participants dominant leg. All trials were then analyzed to determine the timings, angular displacements, and velocities during key events of the PL and POL in the cutting task. The total time to complete the cutting task was not statistically significant between groups; however, Starters demonstrated significantly shorter contact time of the PL during dominant cuts and initiated knee extension of the POL faster than Nonstarters in dominant and nondominant cuts. This preliminary study demonstrates that components of the cutting task differed between groups and may provide an insight for strength and conditioning professionals to assess change of direction technique.

Intrarater Reliability of Neck Strength Measurement of Rugby Union Players Using a Handheld Dynamometer

OBJECTIVE The purpose of this study was to investigate the isometric neck strength profiles of rugby union players and to assess the intrarater reliability of isometric neck strength measurement using a handheld dynamometer. METHODS Twenty-five male, academy-level, rugby union players (forwards [n = 16], backs [n = 9]) were tested on 2 occasions during a training week 2 days apart. Isometric strength of the neck musculature was tested using a handheld dynamometer, for flexion (F), extension (E), left side flexion (LSF), and right side flexion (RSF). The average of 3 trials for each test position was used for statistical analysis. The following isometric neck strength values were obtained: F, E, F:E, LSF, RSF, LSF:RSF, and total isometric strength. RESULTS Intrarater reliability intraclass correlation coefficients ranged from 0.80 to 0.92 (intraclass correlation coefficient values: F, 0.85; E, 0.85; F:E, 0.85; LSF, 0.80; RSF, 0.85; LSF:RSF, 0.91; total isometric strength, 0.92), thus indicating excellent reliability in all instances. Forwards recorded significantly greater E scores compared with backs (637.10 ± 75.15 N vs 537.87 ± 82.25 N). Forwards also recoded significantly greater total isometric neck strength scores (2151.96 ± 231.11 N vs 1814.21 ± 211.26 N). CONCLUSION The results of this study provide isometric neck strength values for the forward and back units in the rugby union and indicate that a handheld dynamometer may be a reliable tool for assessing isometric neck strength in this population.

Normative adductor squeeze test values in elite junior rugby union players.

Objective:To establish normative adductor squeeze test (AST) values in elite junior rugby union players and investigate if differences existed between field position units and categorizations. Design:Cross-sectional study. Setting:National underage screening camp. Participants:One hundred four healthy players attending an under-19 and under-18 national musculoskeletal and fitness screening camp. Players had no history of surgery, no self-reported history of groin or pelvic pain in either limb and no other lower limb injury in the past 3 months, and no pain reported during the testing procedure. Main Outcome Measures:The AST in 3 positions of hip flexion (0, 45, and 90 degrees), position unit, and categorizations. Results:The highest AST values were observed at 45 degrees of hip flexion in all field position categories. No differences were observed between position units and categorizations. Conclusions:Normative AST values in an elite junior rugby union population were established in this investigation. Clinically, the sports medicine professional may use these results in making decisions on the management of both symptomatic and asymptomatic players.

Effects of neck strength training on isometric neck strength in rugby union players.

Objective:To investigate the effectiveness of a neck strengthening program on the isometric neck strength profile of male rugby union players. Design:Controlled laboratory study. Setting:Professional rugby union club. Participants:Fifteen professional and 10 semiprofessional rugby union players. Interventions:The 15 professional players undertook a 5-week neck strengthening intervention, which was performed twice per week, whereas the 10 semiprofessional players acted as the control group. Main Outcome Measures:Isometric strength of the neck musculature was tested using a hand-held dynamometer, for flexion (F), extension (E), left-side flexion (LSF), and right-side flexion (RSF). Preintervention and postintervention evaluations were undertaken. Results:No significant between-group differences in isometric neck strength were noted preintervention. A significant main effect for time was observed (P < 0.05), whereby the intervention group increased isometric neck strength in all planes after the 5-week intervention (F preintervention = 334.45 ± 39.31 N vs F postintervention 396.05 ± 75.55 N; E preintervention = 606.19 ± 97.34 vs E postintervention = 733.88 ± 127.16 N; LSF preintervention = 555.56 ± 88.34 N vs LSF postintervention = 657.14 ± 122.99 N; RSF preintervention = 570.00 ± 106.53 N vs RSF postintervention = 668.00 ± 142.18 N). No significant improvement in neck strength was observed for control group participants. Conclusions:The results of the present study indicate that a 5-week neck strengthening program improves isometric neck strength in rugby union players, which may have implications for injury prevention, screening, and rehabilitation. Clinical Relevance:The strengthening program described in the present study may facilitate rehabilitation specialists in the development of neck injury prevention, screening, and rehabilitation protocols.

The adductor squeeze test: which is the optimal test position for eliciting maximum squeeze values and adductor muscle activity?

Background Groin injuries are a common occurrence in field based sports that have a high component of twisting and turning activities. The adductor squeeze test is commonly utilised, as a diagnostic and injury screening tool. Currently no reports exist in the published literature, which detail the level of activation of the adductor musculature and concomitant squeeze values during the test positions of the adductor squeeze test which are commonly utilised in a clinical setting. Objective The aim of the present study was to investigate the level of adductor musculature surface EMG (SEMG) activity and concomitant squeeze values in a healthy population of male Gaelic games athletes during performance of the adductor squeeze test in the three commonly utilised test positions (ie, 0°, 45°, and 90° of hip flexion). Setting University biomechanics laboratory. Participants 18 male Gaelic games players without any previous or current history of groin or hip injury. Main outcome measures Each participant performed three maximal effort repetitions of the adductor squeeze test in the positions of 0°, 45°, and 90° of hip flexion. Bilateral adductor SEMG activity and concomitant squeeze values quantified by a sphygmomanometer were recorded for each test. Repeated measures ANOVA was used to test for differences in the values obtained during each of the three test positions for both SEMG activity and squeeze values. Results The greatest amount of adductor muscle activity and squeeze values were observed in the 45° of hip flexion test position. Conclusion The results of the present study suggest that the adductor squeeze test performed in a position of 45° of hip flexion is the optimal test position for eliciting maximal adductor muscle activity and squeeze values. Therefore, the 45° of hip flexion test position can be recommended as the optimal test position for injury screening in non-pathological groups.