Effects of head position on back squat power performance


  • Christopher George Offley Cardiff Metropolitan University
  • Jeremy Moody
  • Joseph Esformes
  • Paul Byrne




Back squat, Head position, Kinetics, Rugby union


The effect of head positioning is often not accounted for when optimising performance in the back squat exercise. The primary aim of the study was to identify the most advantageous head position for peak power (PP), peak velocity (PV) and peak force (PF) performance in the back squat exercise. A secondary aim was to identify the most favourable head position. Twenty male rugby union players performed 1x3 repetitions at 75% one repetition maximum (1RM) to determine their preferred pre-intervention head position, followed by 1x3 at 75% 1RM in a flexed (FP), extended (EP) and neutral (NP) neck position, performed in a counterbalanced and randomised order. PP, PV, PF and comfort level (CL) were measured during each repetition. FP resulted in significantly higher PP (3147.50 ± 464.70 W; p<0.05) compared to EP (2730 ± 427.83 W) and NP (2912.95 ± 441.16 W). However, NP resulted in significantly greater CL than FP and EP (3.65 ± 0.59; p<0.05). Therefore, when performing the back squat at 75% 1RM, the FP can be adopted to optimise power performance if there is no pain and no detriment to movement kinematics.



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Adams, K., O'Shea, J.P., O'Shea, K.L. and Climstein, M. (1992). The effect of six weeks of squat, plyometric and squat-plyometric training on power production. Journal of applied sport science research, 6(1), 36-41.

Baker, D. and Nance, S. (1999). The relation between running speed and measures of strength and power in professional rugby league players. The Journal of Strength & Conditioning Research, 13(3), 230-235.

Bertram, D. (2007). Likert scales. Retrieved June 28, 2014, from the University of Calgary, Department of Computer Science. http://poincare.matf.bg.ac.rs/~kristina/topic- dane-likert.pdf

Black, K.M., McClure, P. and Polansky, M. (1996). The influence of different sitting positions on cervical and lumbar posture. Spine, 21(1), 65-70.

Comfort, P. and Kasim, P. (2007). Optimising squat technique. Strength and Conditioning Journal, 29(6), 10.

Comfort, P., McMahon, J.J. and Suchomel, T.J. (2018). Optimising squat technique—Revisited. Strength & Conditioning Journal, 40(6), 68-74. doi: 10.1519/SSC.0000000000000398

De Salles, B.F., Simao, R., Miranda, F., da Silva Novaes, J., Lemos, A. and Willardson, J.M. (2009). Rest interval between sets in strength training. Sports medicine, 39(9), 765-777.

Donnelly, D.V., Berg, W.P. and Fiske, D.M. (2006). The effect of the direction of gaze on the kinematics of the squat exercise. Journal of Strength and conditioning Research, 20(1), 145. doi: 10.1519/00124278-200602000-00023

Graci, V., Van Dillen, L.R. and Salsich, G.B. (2012). Gender differences in trunk, pelvis and lower limb kinematics during a single leg squat. Gait & posture, 36(3), 461-466. doi: 10.1016/j.gaitpost.2012.04.006

Hermassi, S., Chelly, M.S., Tabka, Z., Shephard, R.J. and Chamari, K. (2011). Effects of 8-week in-season upper and lower limb heavy resistance training on the peak power, throwing velocity, and sprint performance of elite male handball players. The Journal of Strength & Conditioning Research, 25(9), 2424-2433.

Jackson, R.P., Phipps, T., Hales, C. and Surber, J. (2003). Pelvic lordosis and alignment in spondylolisthesis. Spine, 28(2), 151-160.

Jones, T.W., Smith, A., Macnaughton, LS and French, D.N. (2016). Strength and Conditioning and concurrent training practices in elite Rugby Union. The Journal of Strength & Conditioning Research, 30(12), 3354-3366. doi: 10.1519/JSC.0000000000001445

Kraska, J.M., Ramsey, M.W., Haff, G.G., Fethke, N., Sands, W.A., Stone, M.E. and Stone, M.H. (2009). Relationship between strength characteristics and unweighted and weighted vertical jump height. International Journal of Sports Physiology and Performance, 4(4), 461-473.

Kritz, M., Cronin, J. and Hume, P. (2009). The bodyweight squat: A movement screen for the squat pattern. Strength & Conditioning Journal, 31(1), 76-85. doi: 10.1519/SSC.0b013e318195eb2f

Lachowetz, T., Evon, J. and Pastiglione, J. (1998). The effect of an upper body strength program on intercollegiate baseball throwing velocity. The Journal of Strength & Conditioning Research, 12(2), 116-119.

McBride, J.M., Blow, D., Kirby, T.J., Haines, T.L., Dayne, A.M. and Triplett, N.T. (2009). Relationship between maximal squat strength and five, ten, and forty yard sprint times. The Journal of Strength & Conditioning Research, 23(6), 1633-1636. doi: 10.1519/JSC.0b013e3181b2b8aa

McBride, J.M., Triplett-McBride, T., Davie, A. and Newton, R.U. (2002). The effect of heavy-vs. light-load jump squats on the development of strength, power, and speed. The Journal of Strength & Conditioning Research, 16(1), 75-82.

Myer, G.D., Kushner, A.M., Brent, J.L., Schoenfeld, B.J., Hugentobler, J., Lloyd, R.S., Vermeil, A., Chu, D.A., Harbin, J. and McGill, S.M. (2014). The back squat: A proposed assessment of functional deficits and technical factors that limit performance. Strength and conditioning journal, 36(6), 4. doi: 10.1519/SSC.0000000000000103

O'Donnell, S., Tavares, F., McMaster, D., Chambers, S. and Driller, M. (2018). The validity and reliability of the GymAware linear position transducer for measuring counter-movement jump performance in female athletes. Measurement in Physical Education and Exercise Science, 22(1), 101-107. doi: 10.1080/1091367X.2017.1399892

Orloff, H., Veil, G. and Askins, R. (1997). Forces on the lumbar spine during the parallel squat. In ISBS-Conference Proceedings Archive.

Scheer, J.K., Tang, J.A., Smith, J.S., Acosta, F.L., Protopsaltis, T.S., Blondel, B., Bess, S., Shaffrey, C.I., Deviren, V., Lafage, V. and Schwab, F. (2013). Cervical spine alignment, sagittal deformity, and clinical implications: a review. Journal of Neurosurgery: Spine, 19(2), 141-159. doi: 10.3171/2013.4.SPINE12838

Schoenfeld, B.J. (2010). Squatting kinematics and kinetics and their application to exercise performance. The Journal of Strength & Conditioning Research, 24(12), 3497-3506. doi: 10.1519/JSC.0b013e3181bac2d7

Speranza, M.J., Gabbett, T.J., Johnston, R.D. and Sheppard, J.M. (2015). Muscular strength and power correlates of tackling ability in semiprofessional rugby league players. The Journal of Strength & Conditioning Research, 29(8), 2071-2078. Doi: 10.1519/JSC.0000000000000897

Swinton, P.A., Lloyd, R., Keogh, J.W., Agouris, I. and Stewart, A.D. (2012). A biomechanical comparison of the traditional squat, powerlifting squat, and box squat. The Journal of Strength & Conditioning Research, 26(7), 1805-1816. Doi: 10.1519/JSC.0b013e3182577067

Walsh, J.C., Quinlan, J.F., Stapleton, R., FitzPatrick, DP and McCormack, D. (2007). Three-dimensional motion analysis of the lumbar spine during "free squat" weight lift training. The American journal of sports medicine, 35(6), 927-932. doi: 10.1177/0363546506298276

Wang, K., Deng, Z., Li, Z., Wang, H. and Zhan, H. (2017). The influence of natural head position on the cervical sagittal alignment. Journal of healthcare engineering, 2017. doi: 10.1155/2017/2941048

Wisløff, U., Castagna, C., Helgerud, J., Jones, R. and Hoff, J. (2004). Strong correlation of maximal squat strength with sprint performance and vertical jump height in elite soccer players. British journal of sports medicine, 38(3), 285-288. Doi: 10.1136/bjsm.2002.002071

Yavuz, H.U., Erdağ, D., Amca, A.M. and Aritan, S. (2015). Kinematic and EMG activities during front and back squat variations in maximum loads. Journal of sports sciences, 33(10), 1058-1066. doi: 10.1080/02640414.2014.984240

Zink, A.J., Perry, A.C., Robertson, B.L., Roach, K.E. and Signorile, J.F. (2006). Peak power, ground reaction forces, and velocity during the squat exercise performed at different loads. The Journal of Strength & Conditioning Research, 20(3), 658-664.






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