Criterion and Construct Validity of an Isometric Midthigh-Pull Dynamometer for Assessing Whole-Body Strength in Professional Rugby League Players

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Nick Dobbin
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Richard Hunwicks
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Ben Jones
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Kevin Till
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Jamie Highton
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Craig Twist
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DOI:
https://doi.org/10.1123/ijspp.2017-0166
In Print:
Volume 13: Issue 2
Page Range:
235–239
Restricted access

Purpose: To examine the criterion and construct validity of an isometric midthigh-pull dynamometer to assess whole-body strength in professional rugby league players. Methods: Fifty-six male rugby league players (33 senior and 23 youth players) performed 4 isometric midthigh-pull efforts (ie, 2 on the dynamometer and 2 on the force platform) in a randomized and counterbalanced order. Results: Isometric peak force was underestimated (P < .05) using the dynamometer compared with the force platform (95% LoA: −213.5 ± 342.6 N). Linear regression showed that peak force derived from the dynamometer explained 85% (adjusted R2 = .85, SEE = 173 N) of the variance in the dependent variable, with the following prediction equation derived: predicted peak force = [1.046 × dynamometer peak force] + 117.594. Cross-validation revealed a nonsignificant bias (P > .05) between the predicted and peak force from the force platform and an adjusted R2 (79.6%) that represented shrinkage of 0.4% relative to the cross-validation model (80%). Peak force was greater for the senior than the youth professionals using the dynamometer (2261.2 ± 222 cf 1725.1 ± 298.0 N, respectively; P < .05). Conclusion: The isometric midthigh pull assessed using a dynamometer underestimates criterion peak force but is capable of distinguishing muscle-function characteristics between professional rugby league players of different standards.

Dobbin, Highton, and Twist are with the Dept of Sport and Exercise Sciences, University of Chester, Chester, United Kingdom. Hunwicks is with Rugby Football League, Leeds, United Kingdom. Till and Jones are with the Inst for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, United Kingdom.

Twist (c.twist@chester.ac.uk) is corresponding author.
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  • 1.

    Comfort P, Haigh A, Matthews MJ. Are changes in maximal squat strength during preseason training reflected in changes in sprint performance in rugby league players? J Strength Cond Res. 2012;26(3):772–776. PubMed doi:10.1519/JSC.0b013e31822a5cbf

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 2.

    Speranza MJ, Gabbett TJ, Johnston RD, Sheppard JM. Muscular strength and power correlates of tackling ability in semiprofessional rugby league players. J Strength Cond Res. 2015;29(8):2071–2078. PubMed doi:10.1519/JSC.0000000000000897

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3.

    Suchomel TJ, Nimphius S, Stone MH. The importance of muscular strength in athletic performance. Sports Med. 2016;46(10):1419–1449. PubMed doi:10.1007/s40279-016-0486-0

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4.

    Gabbett TJ, Ullah S, Finch CF. Identifying risk factors for contact injury in professional rugby league players—application of a frailty model for recurrent injury. J Sci Med Sport. 2012;15(6):496–504. PubMed doi:10.1016/j.jsams.2012.03.017

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5.

    Baker DG, Newton RU. Comparison of lower body strength, power, acceleration, speed, agility, and sprint momentum to describe and compare playing rank among professional rugby league players. J Strength Cond Res. 2008;22(1):153–158. PubMed doi:10.1519/JSC.0b013e31815f9519

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 6.

    Till K, Jones B, Geeson-Brown T. Do physical qualities influence the attainment of professional status within elite 16–19 year old rugby league players? J Sci Med Sport. 2016;19(7):585–589. PubMed doi:10.1016/j.jsams.2015.07.001

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 7.

    Darrall-Jones JD, Jones B, Till K. Anthropometric and physical profiles of english academy rugby union players. J Strength Cond Res. 2015;29(8):2086–2096. PubMed doi:10.1519/JSC.0000000000000872

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 8.

    Meylan CM, Cronin JB, Oliver JL, Hughes MM, Jidovtseff B, Pinder S. The reliability of isoinertial force-velocity-power profiling and maximal strength assessment in youth. Sports Biomech. 2015;14(1):68–80. PubMed doi:10.1080/14763141.2014.982696

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9.

    Abernethy P, Wilson G, Logan P. Strength and power assessment: issues, controversies and challenges. Sports Med. 1995;19(6):401–417. PubMed doi:10.2165/00007256-199519060-00004

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 10.

    Myer GD, Quatman CE, Khoury J, Wall EJ, Hewett TE. Youth versus adult “weightlifting” injuries presenting to United States emergency rooms: accidental versus nonaccidental injury mechanisms. J Strength Cond Res. 2009;23(7):2054–2060. PubMed doi:10.1519/JSC.0b013e3181b86712

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11.

    McGuigan MR, Winchester JB. The relationship between isometric and dynamic strength in college football players. J Sports Sci Med. 2008;7(1):101–105. PubMed doi:10.1249/01.mss.0000322664.81874.75

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12.

    McGuigan MR, Newton MJ, Winchester JB, Nelson AG. Relationship between isometric and dynamic strength in recreationally trained men. J Strength Cond Res. 2010;24(9):2570–2573. PubMed doi:10.1519/JSC.0b013e3181ecd381

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 13.

    Crewther BT, Kilduff LP, Cook CJ, et al. Relationships between salivary free testosterone and the expression of force and power in elite athletes. J Sports Med Phys Fitness. 2012;52(2):221–227. PubMed

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 14.

    Dos’santos T, Jones PA, Kelly J, McMahon JJ, Comfort P, Thomas C. Effect of sampling frequency on isometric midthigh-pull kinetics. Int J Sports Physiol Perform. 2016;11(2):255–260. PubMed doi:10.1123/ijspp.2015-0222

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15.

    West DJ, Owen NJ, Jones MR, et al. Relationships between force-time characteristics of the isometric midthigh pull and dynamic performance in professional rugby league players. J Strength Cond Res. 2011;25(11):3070–3075. PubMed doi:10.1519/JSC.0b013e318212dcd5

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 16.

    McMaster DT, Gill N, Cronin J, McGuigan M. A brief review of strength and ballistic assessment methodologies in sport. Sports Med. 2014;44(5):603–623. PubMed doi:10.1007/s40279-014-0145-2

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17.

    De Witt JK, English KL, Crowell JB, et al. Isometric mid-thigh pull reliability and relationship to deadlift 1RM. J Strength Cond Res. 2016. PubMed doi:10.1519/JSC.0000000000001605

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 18.

    James LP, Roberst LA, Haff GG, Kelly VG, Beckman EM. The validity and reliability of a portable isometric mid-thigh clean pull. J Strength Cond Res. 2017;31(5):1378–1386. PubMed doi:10.1519/JSC.0000000000001201

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 19.

    Haugen T, Buchheit M. Sprint running performance monitoring: methodological and practical considerations. Sports Med. 2016;46(5):641–656. PubMed doi:10.1007/s40279-015-0446-0

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20.

    Baumgarter TA, Jackson AS. Measurement for Evaluation in Physical Education and Exercise Science. Dubuque, IA: Wm C Brown; 1987.

  • 21.

    Dos’santos T, Thomas C, Comfort P, et al. Between-session reliability of isometric mid-thigh pull kinetics and maximal power clean performance in male youth soccer players. J Strength Cond Res. 2017. PubMed doi:10.1519/JSC.0000000000001830

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22.

    Thomas C, Jones PA, Rothwell J, Chiang CY, Comfort P. An investigation into the relationship between maximum isometric strength and vertical jump performance. J Strength Cond Res. 2015;29(8):2176–2185. PubMed doi:10.1519/JSC.0000000000000866

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 23.

    Beckham G, Mizuguchi S, Carter C, et al. Relationships of isometric mid-thigh pull variables to weightlifting performance. J Sports Med Phys Fitness. 2013;53(5):573–581. PubMed

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 24.

    Bland MJ, Altman DG. Statistic methods for measuring agreement of clinical measurement. Lancet. 1986;327(8476):307–310. PubMed doi:10.1016/S0140-6736(86)90837-8

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 25.

    Hopkins WG, Marshall SW, Batterham AM, Hanin J. Progressive statistics for studies in sports medicine and exercise science. Med Sci Sports Exerc. 2009;41(1):3–13. PubMed doi:10.1249/MSS.0b013e31818cb278

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 26.

    Field A. Discovering Statistics Using IBM SPSS Statistics: And Sex and Drugs and Rock ’n’ Roll. 4th ed. London, UK: Sage; 2013.

  • 27.

    Crewther BT, Gill N, Weatherby RP, Lowe T. A comparison of ratio and allometric scaling methods for normalizing power and strength in elite rugby union players. J Sports Sci. 2009;27(14):1575–1580. PubMed doi:10.1080/02640410903348657

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 28.

    Hopkins WG. Spreadsheets for analysis of controlled trials with adjustment for a subject characteristic. Sportscience. 2006;10:46–50.

  • 29.

    Harris GR, Stone MH, O’Bryant HS, Proulx CM, Johnson RL. Short-term performance effects of high power, high force, or combined weight-training methods. J Strength Cond Res. 2000;14(1):14–20. doi:10.1519/1533-4287(2000)014<0014:STPEOH>2.0.CO;2

    • Search Google Scholar
    • Export Citation
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