Reliability, Usefulness, and Validity of Field-Based Vertical Jump Measuring Devices

Comyns, TM,Murphy, J, and O’Leary, D. Reliability, usefulness, and validity of field-based vertical jump measuring devices. J Strength Cond Res 37(8): 1594–1599, 2023—The purpose of this study was to examine the test-retest reliability, usefulness, and validity of field based devices, in determining jump height (JH) during a countermovement jump (CMJ). Twenty-one male (22.8 6 2.4 years; 1.82 6 0.07m; 86.0610.4 kg) and 7 female field sport athletes (20.561.5 years; 1.6560.06 m; 65.467.2 kg) performed 3CMJs with data simultaneously recorded using a force plate (criterion measure), Opto jump, Output Capture, and Push-Band 2.0. Reliability was determined by intraclass correlation (ICC) and coefficient of variation (CV) analyses. Usefulness was assessed by comparing typical error (TE) with the smallest worthwhile change (SWC), and the validity analyses involved repeated measures analysis of variance with post hoc analysis, Pearson correlation coefficient (r), coefficient of determination, and Bland-Altman 95%limits of agreement analyses. All 3 field-based devices were deemed reliable in assessing CMJ height as the respective ICCs $ 0.80 and the CV # 10%. Only the Opto jump and Output Capture devices were rated as “good” at detecting the SWC in performance (Opto jump SWC: 1.44.TE: 1.04; Output Capture SWC: 1.47 . TE: 1.05). The Output Capture device demonstrated acceptable validity for CMJ height assessment, whereas the Push-Band 2.0 showed systematic bias when compared with the criterion force plate data. Systematic difference was also evident for the Opto jump potentially due to the optical switching-cell position on the Opto jump. Although all 3 devices showed excellent reliability, the Opto jump and Output Capture devices offer practitioners a cost effective, reliable, and valid method of assessing the smallest worthwhile change in CMJ performance in an applied setting

COMPARISON OF THE RELIABILITY OF PEAK FORCE MEASURED DURING AN ISOMETRIC MID-THIGH PULL AND ISOMETRIC SQUAT.

The purpose of this study was to compare peak force produced during the isometric midthigh pull (IMTP) and isometric squat (IsoSquat), performed at the same knee and hip angles (135 – 140°) and determine the reliability of both tests. Following a specific warmup, 22 international athletes from different sports performed 2 maximal effort tests of both the IMTP and IsoSquat. Peak force achieved during the IsoSquat was significantly greater (p = 0.01) than peak force achieved during the IMTP. Both tests were highly reliable for peak force (�������� ���� ���������� ������ ���� ��%). Therefore, strength and conditioning coaches can select either test when examining lower extremity maximum strength. However, the IsoSquat produces higher peak force values and this may be a more accurate reflection of the athlete’s maximum strength

The relationship between physical and wellness measures and injury in amateur rugby union players

peer-reviewedObjectives To investigate factors associated with injury in amateur male and female rugby union players. Design A prospective cohort study. Setting Amateur rugby clubs in Ireland. Participants Male (n = 113) and female (n = 24) amateur rugby union players from 5 of the top 58 amateur clubs in Ireland. Main outcome measures Pre-season testing included physical tests assessing hamstring flexibility, dorsiflexion range of movement, adductor muscle strength and foot position. Wellness questionnaires assessed sleep quality (PSQI), coping skills (ACSI-28) and support levels (PASS-Q). Players were monitored throughout the season for injury. Results The time-loss match injury incidence rate was 48.2/1000 player hours for males and 45.2/1000 player hours for females. Two risk profiles emerged involving; ‘age + navicular drop + training pitch surface’ (53%) and ‘age + navicular drop + groin strength’ (16%). An inverse relationship between groin strength and groin injury was found for the ‘backs’ players (−0.307, p < 0.05). Using the PSQI, 61% of players had poor sleep quality, however no relationship between the wellness questionnaires and injury was found. Conclusion Two injury risk profiles emerged, associated with subsequent injury occurrence. Using these risk profiles, individualized prevention strategies may be designed regarding deficits in groin muscle strength and identifying foot alignment.ACCEPTEDpeer-reviewe

Strength and conditioning coaches\u27 application of the session rating perceived exertion method of monitoring within professional rugby union

Session rating of perceived exertion (session-RPE) is a method of monitoring and managing training loads. The purpose of this study was to research how and for what purpose strength and conditioning (S&C) coaches implement this monitoring method within professional rugby union. The study also aimed to assess if S&C coaches found this monitoring method to be valid and effective. An online survey containing 24 fixed response questions was used to assess how S&C coaches applied the session-RPE method. The survey was piloted with expert researchers and practitioners in the area of session-RPE prior to distribution and alterations were made to the survey based on the experts’ feedback. Twenty S&C coaches working with professional rugby union clubs in Ireland, England, Scotland and Wales completed the survey. The coaches’ responses indicated that the majority found the session-RPE to be a valid and effective monitoring method. While some good implementation practices were identified, not all of the coaches adhered to these guidelines which may impact on the accuracy of the collected data. For example, 30% of coaches do not collect the RPE for every session that a player does per week limiting the use of the session-RPE variables cumulative training load, training monotony, training strain and acute:chronic load ratio. S&C coaches within rugby should consider using session-RPE as a method of monitoring and implement the method in a manner reflective of research findings to enhance the potential applications of this system in maximising adaptations and minimising the risk of injury

Strength and conditioning coaches' application of the session rating perceived exertion method of monitoring within professional rugby union

Session rating of perceived exertion (session-RPE) is a method of monitoring and managing training loads. The purpose of this study was to research how and for what purpose strength and conditioning (S&C) coaches implement this monitoring method within professional rugby union. The study also aimed to assess if S&C coaches found this monitoring method to be valid and effective. An online survey containing 24 fixed response questions was used to assess how S&C coaches applied the session-RPE method. The survey was piloted with expert researchers and practitioners in the area of session-RPE prior to distribution and alterations were made to the survey based on the experts’ feedback. Twenty S&C coaches working with professional rugby union clubs in Ireland, England, Scotland and Wales completed the survey. The coaches’ responses indicated that the majority found the session-RPE to be a valid and effective monitoring method. While some good implementation practices were identified, not all of the coaches adhered to these guidelines which may impact on the accuracy of the collected data. For example, 30% of coaches do not collect the RPE for every session that a player does per week limiting the use of the session-RPE variables cumulative training load, training monotony, training strain and acute:chronic load ratio. S&C coaches within rugby should consider using session-RPE as a method of monitoring and implement the method in a manner reflective of research findings to enhance the potential applications of this system in maximising adaptations and minimising the risk of injury

The application of postactivation potentiaion methods to improve sprint speed

THIS ARTICLE EXAMINES THE APPLICATION OF A VARIETY OF MODALITIES TO ELICIT A POSTACTIVATION POTENTIATION (PAP) RESPONSE IN SPRINTING. WE PRESENT THE EXISTING LITERATURE ON THE ACUTE EFFECTS OF BACK SQUATS, POWER CLEANS, PLYOMETRICS, AND SLED PULLING ON SPRINT DISTANCES RANGING FROM 5 TO 50 M. WE ALSO DISCUSS AND PROVIDE AN EXAMPLE OFHOWCOACHES CAN ASSESS THE INDIVIDUAL EFFECTS OF PAP PROTOCOLS ON THEIR ATHLETES TO IDENTIFY WHETHER A PROTOCOL ELICITS AN ACUTE IMPROVEMENT OR IMPAIRMENT IN PERFORMANCE. FINALLY, WE PROVIDE PRACTICAL RECOMMENDATIONS ON HOW COACHES CAN INCORPORATE THESE METHODS INTO A SPRINT TRAINING SESSION

Applications of the session rating of perceived exertion system in professional rugby union

This article instructs strength and conditioning practitioners in the use of the session RPE system of training load monitoring in the context of the professional rugby union environment. An explanation of the system and the research underpinning its validity and reliability is presented. The use of the system to manage squad and individual player training plans within weeks and across weeks is detailed. Common errors which can be encountered when using the system within professional rugby union are addressed