CONTEXT: Proper conditioning of the neck muscles may play a role in reducing the risk of neck injury and, possibly, concussions in contact sports. However, the ability to reliably measure the force-time-based variables that might be relevant for this purpose has not been addressed. OBJECTIVE: To assess the between-days reliability of discrete force-time-based variables of neck muscles during maximal voluntary isometric contractions in 5 directions. DESIGN: Cohort study. SETTING: University research center. PATIENTS OR OTHER PARTICIPANTS: Twenty-six highly physically active men (age = 21.6 ± 2.1 years, height = 1.85 ± 0.09 m, mass = 81.6 ± 9.9 kg, head circumference = 0.58 ± 0.01 m, neck circumference = 0.39 ± 0.02 m). INTERVENTION(S): We used a custom-built testing apparatus to measure maximal voluntary isometric contractions of the neck muscles in 5 directions (extension, flexion, protraction, left lateral bending, and right lateral bending) on 2 separate occasions separated by 7 to 8 days. MAIN OUTCOME MEASURE(S): Variables measured were peak force (PF), rate of force development (RFD), and time to 50% of PF (T(50)PF). Reliability indices calculated for each variable comprised the difference in scores between the testing sessions, with corresponding 95% confidence intervals, the coefficient of variation of the typical error of measurement (CV(TE)), and intraclass correlation coefficients (ICC [3,3]). RESULTS: No evidence of systematic bias was detected for the dependent measures across any movement direction; retest differences in measurements were between 1.8% and 2.7%, with corresponding 95% confidence interval ranges of less than 10% and overlapping zero. The CV(TE) was lowest for PF (range, 2.4%-6.3%) across all testing directions, followed by RFD (range, 4.8%-9.0%) and T(50)PF (range, 7.1%-9.3%). The ICC score range for all dependent measures was 0.90 to 0.99. CONCLUSIONS: Discrete variables representative of the force-generating capacity of neck muscles under isometric conditions can be measured with an acceptable degree of reliability. This finding has possible applications for investigating the role of neck muscle strength-training programs in reducing the risk of injuries in sport settings.
CONTEXT: Proper conditioning of the neck muscles may play a role in reducing the risk of neck injury and, possibly, concussions in contact sports. However, the ability to reliably measure the force-time-based variables that might be relevant for this purpose has not been addressed. OBJECTIVE: To assess the between-days reliability of discrete force-time-based variables of neck muscles during maximal voluntary isometric contractions in 5 directions. DESIGN: Cohort study. SETTING: University research center. PATIENTS OR OTHER PARTICIPANTS: Twenty-six highly physically active men (age = 21.6 ± 2.1 years, height = 1.85 ± 0.09 m, mass = 81.6 ± 9.9 kg, head circumference = 0.58 ± 0.01 m, neck circumference = 0.39 ± 0.02 m). INTERVENTION(S): We used a custom-built testing apparatus to measure maximal voluntary isometric contractions of the neck muscles in 5 directions (extension, flexion, protraction, left lateral bending, and right lateral bending) on 2 separate occasions separated by 7 to 8 days. MAIN OUTCOME MEASURE(S): Variables measured were peak force (PF), rate of force development (RFD), and time to 50% of PF (T(50)PF). Reliability indices calculated for each variable comprised the difference in scores between the testing sessions, with corresponding 95% confidence intervals, the coefficient of variation of the typical error of measurement (CV(TE)), and intraclass correlation coefficients (ICC [3,3]). RESULTS: No evidence of systematic bias was detected for the dependent measures across any movement direction; retest differences in measurements were between 1.8% and 2.7%, with corresponding 95% confidence interval ranges of less than 10% and overlapping zero. The CV(TE) was lowest for PF (range, 2.4%-6.3%) across all testing directions, followed by RFD (range, 4.8%-9.0%) and T(50)PF (range, 7.1%-9.3%). The ICC score range for all dependent measures was 0.90 to 0.99. CONCLUSIONS: Discrete variables representative of the force-generating capacity of neck muscles under isometric conditions can be measured with an acceptable degree of reliability. This finding has possible applications for investigating the role of neck muscle strength-training programs in reducing the risk of injuries in sport settings.
Authors: S Levoska; S Keinänen-Kiukanniemi; O Hämäläinen; T Jäms ̈; H Vanharanta Journal: Clin Biomech (Bristol, Avon) Date: 1992-02 Impact factor: 2.063
Authors: John M Popovich; N Peter Reeves; M Cody Priess; Jacek Cholewicki; Jongeun Choi; Clark J Radcliffe Journal: J Biomech Date: 2014-11-27 Impact factor: 2.712
Authors: Eva Catenaccio; Weiya Mu; Atira Kaplan; Roman Fleysher; Namhee Kim; Tamar Bachrach; Malka Zughaft Sears; Oren Jaspan; Jaclyn Caccese; Mimi Kim; Mark Wagshul; Walter F Stewart; Richard B Lipton; Michael L Lipton Journal: PM R Date: 2017-02-05 Impact factor: 2.298
Authors: David A Krause; Kelsey A Hansen; Matthew J Hastreiter; Taylor N Kuhn; Molly L Peichel; John H Hollman Journal: Sports Health Date: 2018-11-20 Impact factor: 3.843