5 Examination of the relationship between changes in workload and changes in loaded countermovement jump during a rugby union season

2021 ◽  
Vol 55 (16) ◽  
pp. 941.3-942
Author(s):  
Rob Strong ◽  
Daniel West ◽  
Joe Kupsarevic
Keyword(s):  
Peak Power ◽  
Rank Order ◽  
Rugby Union ◽  
Countermovement Jump ◽  
Match Play ◽  
Time To Peak ◽  
Significant Relationships ◽  
Flight Season ◽  
Acute Changes ◽  
The Relationship

BackgroundThe loaded countermovement jump (CMJ) is a variation on the normal CMJ (bodyweight-only), used routinely in sport settings as a measure of neuromuscular fatigue (NMF). Although commonplace, the CMJ variables that are most sensitive to NMF remain somewhat unclear.PurposeThe aim of this study was to examine the relationship between changes in workload and changes in the loaded CMJ; specifically, to determine its suitability for assessment of NMF.MethodsEighteen professional rugby union players performed loaded CMJ tests on seven occasions over the course of thirteen weeks, during an English top-flight season. Eight CMJ variables were measured, assessing different aspects of the CMJ. Workload was measured by GPS total distance and was the sum of the previous week’s data, recorded in on-field training and match-play. Spearman’s rank-order correlations were calculated to identify the relationship between changes in workload and changes in loaded CMJ variables.ResultsNo significant relationships were found between loaded CMJ variables and workload with no lag or workload lagged one week. Significant relationships were found between workload lagged 2 weeks and flight time/contact time (FT-CT; rs=-0.35; p=0.04) and time to peak power (TtPP; rs=0.35; p=0.05).ConclusionThis study suggests loaded CMJ is not a suitable test to monitor acute changes to NMF. However, results also indicate that FT-CT and TtPP, are associated with changes in workload lagged 2-weeks. Therefore, certain CMJ variables may prove useful to help prescribe alterations to athlete training plans following periods of heavy workload.

Relative Net Vertical Impulse Determines Jumping Performance

2011 ◽  
Vol 27 (3) ◽  
pp. 207-214 ◽  
Author(s):  
Tyler J. Kirby ◽  
Jeffrey M. McBride ◽  
Tracie L. Haines ◽  
Andrea M. Dayne
Keyword(s):  
Body Mass ◽  
Peak Power ◽  
Vertical Jump ◽  
Peak Force ◽  
Jump Height ◽  
Countermovement Jump ◽  
Jump Performance ◽  
Velocity Peak ◽  
Force Peak ◽  
The Relationship

The purpose of this investigation was to determine the relationship between relative net vertical impulse and jump height in a countermovement jump and static jump performed to varying squat depths. Ten college-aged males with 2 years of jumping experience participated in this investigation (age: 23.3 ± 1.5 years; height: 176.7 ± 4.5 cm; body mass: 84.4 ± 10.1 kg). Subjects performed a series of static jumps and countermovement jumps in a randomized fashion to a depth of 0.15, 0.30, 0.45, 0.60, and 0.75 m and a self-selected depth (static jump depth = 0.38 ± 0.08 m, countermovement jump depth = 0.49 ± 0.06 m). During the concentric phase of each jump, peak force, peak velocity, peak power, jump height, and net vertical impulse were recorded and analyzed. Net vertical impulse was divided by body mass to produce relative net vertical impulse. Increasing squat depth corresponded to a decrease in peak force and an increase in jump height and relative net vertical impulse for both static jump and countermovement jump. Across all depths, relative net vertical impulse was statistically significantly correlated to jump height in the static jump (r= .9337,p< .0001, power = 1.000) and countermovement jump (r= .925,p< .0001, power = 1.000). Across all depths, peak force was negatively correlated to jump height in the static jump (r= –0.3947,p= .0018, power = 0.8831) and countermovement jump (r= –0.4080,p= .0012, power = 0.9050). These results indicate that relative net vertical impulse can be used to assess vertical jump performance, regardless of initial squat depth, and that peak force may not be the best measure to assess vertical jump performance.

scholarly journals Which anthropometric and lower body power variables are predictive of professional and amateur playing status in male rugby union players?

2018 ◽  
Vol 14 (1) ◽  
pp. 82-90 ◽  
Author(s):  
Thomas W Jones ◽  
Karen Keane ◽  
Andrew Smith ◽  
Jack Dent ◽  
Kevin McShane ◽  
...  
Keyword(s):  
Physical Performance ◽  
Peak Power ◽  
Peak Velocity ◽  
Rugby Union ◽  
Peak Force ◽  
Lower Body ◽  
Anthropometric Measures ◽  
Standard Data ◽  
Time To Peak ◽  
Lower Body Power

The purpose of this study was to compare anthropometric and lower body power measurements between current professional and amateur male rugby union players. The present study also sought to determine which anthropometric and physical performance variables were predictive of playing standard. Thirty professional and 30 amateur RU players performed Wattbike 6 s maximal effort (WB6S) and countermovement (CMJ) and squat jump (SJ) assessments, anthropometric measures were also taken. Dependant variables recorded and analysed including: body mass, stature, Σ8 site skinfolds, WB6S absolute and relative peak power, CMJ and SJ average concentric force, jump height, peak velocity, time to peak force, rate of force development (RFD) and absolute and relative peak force and power. Professional players were heavier, taller and leaner than their amateur counterparts ( p < 0.05). Professional players performed significantly better in all physical performance measures except CMJ and SJ time to peak force, CMJ RFD and SJ relative peak force. Variables which were predictive of playing standard were: Σ8 skinfolds, CMJ peak velocity and WB6S absolute and relative peak power ( p < 0.05). These findings indicate that the current body of male professional RU players is anthropometrically and physically superior to their amateur counterparts, although not all variables assessed here were predictive of playing standard. Data presented here indicate that Σ8 skinfolds, WB6S absolute and relative power and CMJ peak velocity are predictive of playing standard, whereas other anthropometric and strength and power variables are not.

scholarly journals Relationship Between 2 Standardized Tackling Proficiency Tests and Rugby League Match-Play Tackle Performance

2018 ◽  
Vol 13 (6) ◽  
pp. 770-776 ◽  
Author(s):  
Michael J.A. Speranza ◽  
Tim J. Gabbett ◽  
David A. Greene ◽  
Rich D. Johnston ◽  
Andrew D. Townshend
Keyword(s):  
Rank Order ◽  
Correlation Coefficients ◽  
Rugby League ◽  
Proficiency Tests ◽  
Lower Body ◽  
Spearman Rank Order Correlation ◽  
Match Play ◽  
Body Strength ◽  
Lower Body Strength ◽  
The Relationship

This study investigated the relationship between 2 different assessments of tackling ability, physical qualities, and match-play performance in semiprofessional rugby league players. A total of 18 semiprofessional rugby league players (mean [SD]: age = 23.1 [2.0] y and body mass = 98.8 [11.8] kg) underwent tests of upper- and lower-body strength and power. Tackling ability was assessed using video analysis of under- and over-the-ball tackle drills. A total of 2360 tackles were analyzed from match play. Over-the-ball tackle ability was positively related to the proportion of dominant tackles (Spearman rank-order correlation coefficients [rs] = .52; 95% confidence interval [CI] .07–.79, P = .03) and average play-the-ball speeds (rs = .50; 95% CI .04–.78, P = .03) and negatively related to tackles that conceded offloads (rs = −.55; 95% CI −.78 to .04, P = .04). Under-the-ball tackle ability was significantly related to the proportion of dominant tackles (rs = .57; 95% CI .14–.82, P = .01) and missed tackles (rs = −.48; 95% CI −.77 to .02, P = .05). Good over-the-ball tacklers performed proportionally more dominant tackles, allowed significantly fewer offloads, and had longer average play-the-ball speeds. Good under-the-ball tacklers missed proportionately fewer tackles. This study suggests that both the under-the-ball and over-the-ball standardized tackle assessments are associated with varying indicators of match-play tackle performance and justifies the practical utility of these tests to assess and develop both types of tackles.

scholarly journals Relationships Between Sprint, Jumping and Strength Abilities, and 800 M Performance in Male Athletes of National and International Levels

2017 ◽  
Vol 58 (1) ◽  
pp. 187-195 ◽  
Author(s):  
Beatriz Bachero-Mena ◽  
Fernando Pareja-Blanco ◽  
David Rodríguez-Rosell ◽  
Juan Manuel Yáñez-García ◽  
Ricardo Mora-Custodio ◽  
...  
Keyword(s):  
Countermovement Jump ◽  
Male Athletes ◽  
Running Performance ◽  
Significant Relationships ◽  
High Level ◽  
The Relationship

AbstractThis study analysed the relationships between sprinting, jumping and strength abilities, with regard to 800 m running performance. Fourteen athletes of national and international levels in 800 m (personal best: 1:43-1:58 min:ss) completed sprint tests (20 m and 200 m), a countermovement jump, jump squat and full squat test as well as an 800 m race. Significant relationships (p < 0.01) were observed between 800 m performance and sprint tests: 20 m (r = 0.72) and 200 m (r = 0.84). Analysing the 200 m run, the magnitude of the relationship between the first to the last 50 m interval times and the 800 m time tended to increase (1st 50 m: r = 0.71; 2nd 50 m: r = 0.72; 3rd 50 m: r = 0.81; 4th 50 m: r = 0.85). Performance in 800 m also correlated significantly (p < 0.01-0.05) with strength variables: the countermovement jump (r = -0.69), jump squat (r = -0.65), and full squat test (r = -0.58). Performance of 800 m in high-level athletes was related to sprint, strength and jumping abilities, with 200 m and the latest 50 m of the 200 m being the variables that most explained the variance of the 800 m performance.

scholarly journals Workload, Fatigue, and Muscle Damage in an Under-20 Rugby Union Team Over an Intensified International Tournament

2018 ◽  
Vol 13 (8) ◽  
pp. 1059-1066 ◽  
Author(s):  
Mathieu Lacome ◽  
Christopher Carling ◽  
Jean-Philippe Hager ◽  
Gerard Dine ◽  
Julien Piscione
Keyword(s):  
Muscle Damage ◽  
High Speed ◽  
Perceived Exertion ◽  
Well Being ◽  
Rugby Union ◽  
Rating Of Perceived Exertion ◽  
Exposure Group ◽  
Progressive Decrease ◽  
Countermovement Jump ◽  
Match Play

Purpose:To examine the effects of an intensified tournament on workload, perceptual and neuromuscular fatigue, and muscle-damage responses in an international under-20 rugby union team.Methods:Players were subdivided into a high-exposure group (HEG, n = 13) and a low-exposure group (LEG, n = 11) according to match-play exposure time. Measures monitored over the 19-d period included training session (n = 10) and match (n = 5) workload determined via global positioning systems and session rating of perceived exertion. Well-being scores, countermovement jump height performance, and blood creatine kinase concentrations were collected at various time points.Results:Analysis of workload cumulated across the tournament entirety for training and match play combined showed that high-speed running distance was similar between groups, while a very likely larger session rating of perceived exertion load was reported in HEG vs LEG. In HEG, high-speed activity fluctuated across the 5 successive matches, albeit with no clear trend for a progressive decrease. No clear tendency for a progressive decrease in well-being scores prior to or following matches was observed in either group. In HEG, trivial to possibly small reductions in postmatch countermovement jump performance were observed, while unclear to most likely moderate increases in prematch blood creatine kinase concentrations occurred until prior to match 4.Conclusions:The magnitude of match-to-match changes in external workload, perceptual and neuromuscular fatigue, and muscle damage was generally unclear or small. These results suggest that irrespective of exposure time to match play players generally maintained performance and readiness to play across the intensified tournament. These findings support the need for holistic systematic player-monitoring programs.

scholarly journals Relationships of the 5-Jump Test (5JT) Performance of Youth Players With Volleyball Specific’ Laboratory Tests for Explosive Power

2020 ◽  
Vol 14 (6) ◽  
pp. 155798832097768
Author(s):  
Karim Ben Ayed ◽  
Helmi Ben Saad ◽  
Mohamed Ali Hammami ◽  
Imed Latiri
Keyword(s):  
Peak Power ◽  
Laboratory Tests ◽  
Leg Length ◽  
Countermovement Jump ◽  
Squat Jump ◽  
Explosive Power ◽  
Jump Test ◽  
Volleyball Players ◽  
S Peak ◽  
The Relationship

Volleyball involves movements with and/or without horizontal approaches (i.e., spike jumps, jump setting, blocking). The 5-jump test (5JT) was suggested to assess lower limb explosive power of athletes competing in some disciplines (e.g., soccer, judo, running). It appears that no previous study has investigated the 5JT performance components in volleyball players. This study aimed to test the relationship between 5JT performance and two specific laboratory tests for explosive power (i.e., countermovement jump [CMJ] and squat jump [SJ]). Forty volleyball players (boys, mean age: 12.4 ± 0.8 years) were tested for 5JT, CMJ, and SJ tests. 5JT performance was expressed in absolute terms (m), and relative to leg length (5JTLL) and body mass (5JTBM). The SJ and CMJ tests were evaluated using the optojump photoelectric cells and the following data were collected: peak power (Pp) of jump (W, W.kg-0.67), peak jumping force (Fpeak, N), peak jumping velocity (Vpeak, m/s), peak heights of CMJ and SJ (CMJH and SJH, respectively, cm). Only significant ( p < .05) Pearson product-moment correlations ( r) > 0.30 were considered. 5JT performance was significantly correlated with SJ, Vpeak ( r = 0.90), SJH ( r = 0.88), Pp [W.kg-0.67 ( r = 0.86), W ( r = 0.72)], Fpeak ( r = 0.45); and CMJ, Vpeak ( r = 0.82), CMJH ( r = 0.80), Pp [W.kg-0.67 ( r = 0.89), W ( r = 0.85)], Fpeak ( r = 0.73). 5JTLL values were significantly related to SJ, Pp [W ( r = 0.81), W.kg-0.67 ( r = 0.74)], Vpeak ( r = 0.82); and CMJ, Pp [W ( r = 0.73), W.kg-0.67 ( r = 0.84)], Vpeak ( r = 0.75), Fpeak ( r = 0.67)]. 5JTBM values were significantly related to SJ, Pp (W, r = −0.43). To conclude, in youth volleyball players, the 5JT may be viewed as an explosive strength diagnostic instrument under field circumstances.

Linking ‘Halal’ Friendly Hotel Attributes and Customer Satisfaction:The Islamic Tourism Sector

2016 ◽  
Vol 4 (4) ◽  
pp. 43
Author(s):  
Lennora Putit ◽  
Mazzini Muda ◽  
Ainul Nadzirah Mahmood ◽  
Nor Zafirah Ahmad Taufek ◽  
Norhayati Wahib
Keyword(s):  
Customer Satisfaction ◽  
Dress Code ◽  
Significant Relationships ◽  
Tourism Sector ◽  
Managerial Implications ◽  
Halal Food ◽  
Increasing Demand ◽  
Islamic Dress ◽  
The Relationship ◽  
Survey Questionnaires

An increasing demand for Islamic tourism has driven the concept of a ‘Halal’ (or permissible) friendly hotel into another level of business insight within the consumers’ travel market. The concept via its unique value proposition has rapidly become very attractive not only to Muslim tourists, but also to non-Muslim tourists globally. This study aims to examine the relationship linking ‘Halal’ friendly hotel attributes and customer satisfaction. Using purposive sampling, a total of 410 survey questionnaires were distributed to targeted respondents with only 323 usable feedbacks and used for data analysis. Regression results revealed that four main “Halal-friendly hotel” attributes have significant relationships with customer satisfaction. These include prayer facilities, Halal food, Islamic dress code and general Islamic morality. Of these four attributes, prayer facilities proved to have the most significant impact on customer satisfaction. Findings and managerial implications were further discussed in this article.

Whos Chatting?: Interplay between Personality and WhatsApp Use

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Himanshu Rajput
Keyword(s):  
Logistic Regression ◽  
Multiple Regression ◽  
Big Five ◽  
Personality Assessment ◽  
The Internet ◽  
Big Five Inventory ◽  
Significant Relationships ◽  
Indian Context ◽  
High Penetration ◽  
The Relationship

Smartphone-based messaging applications have shown phenomenal growth with the proliferation of the internet coupled with the high penetration of smartphones into masses. The current study is an attempt to understand the relationship between the individuals personality and their use of WhatsApp, a popular smartphone-based messaging application in Indian context. For personality assessment the study takes Big Five Inventory. A questionnaire consisting items on individual WhatsApp use and Big Five Inventory was administered to students in an Indian University. Multiple regression and logistic regression revealed significant relationships between personality and WhatsApp usage and use of its different inbuilt functions.

scholarly journals How Is Sleep Related to Anxiety or Depression in Older Adults With Dementia?

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 619-619
Author(s):  
Yeji Hwang ◽  
Nancy Hodgson
Keyword(s):  
Anxiety And Depression ◽  
Regression Analyses ◽  
Subjective Sleep Quality ◽  
Subjective Sleep ◽  
Significant Relationships ◽  
People With Dementia ◽  
The Family ◽  
Study Participants ◽  
Anxiety Depression ◽  
The Relationship

Abstract Anxiety and depression are one of the most distressing symptoms for the family caregivers. Little is known about the relationship between sleep impairments and anxiety/depression in this population and how objective and subjective sleep measures differ in relation to anxiety. This study was designed to examine the relationship between sleep impairments and anxiety/depression in people with dementia, using both subjective and objective sleep measures. Among the 170 study participants, 50% (n=85) reported to have anxiety/depression. In univariate logistic regression analyses on anxiety/depression, adjusting for dementia stage, people with more subjective sleep impairment had higher odds of having anxiety/depression (OR=1.111; 95% CI: 1.020-1.211, p=0.016) and people with poorer subjective sleep quality had higher odds of having anxiety/depression (OR=1.702; 95% CI: 1.046-2.769, p=0.032). Objective sleep measures from actigraphy did not show any significant relationships to anxiety/depression. The results suggest that subjective sleep measures are closely related to anxiety/depression in this population.

scholarly journals Ethics of Retailers and Consumer Behavior in E-Commerce

2020 ◽  
Vol 11 (1) ◽  
pp. 107-126
Author(s):  
Zhi Yang ◽  
Quang Van Ngo ◽  
Chung Xuan Thi Nguyen
Keyword(s):  
Electronic Commerce ◽  
Communication Technology ◽  
Purchase Intention ◽  
Purchase Decision ◽  
Information Communication ◽  
Significant Relationships ◽  
Online Retailers ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

In the era of the information-communication technology with the development of electronic commerce, consumers can buy almost everything anywhere and at any time. One of the greatest benefits of e-commerce has been the convenience and the vast choices which consumers get online. However, some serious issues exist that impede consumers from transaction online. These issues have attracted the attention of many marketing researchers in recent years. In this research, the authors focus on the impact of consumers' ethics perception of e-retailer on their purchase intention and satisfaction. The authors also try to clarify the roles of trust and commitment in the relationship of ethics on consumers purchase decision and satisfaction because of their importance in e-commerce but also the privation in the research of previous studies. The data collected from a survey of 390 online consumers in Vietnam. Results reveal that there are significant relationships between online retailers' ethics and consumers' purchase intention and satisfaction via the mediation of trust and commitment.

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