TY - JOUR
T1 - The influence of maximal strength and knee angle on the reliability of peak force in the isometric squat
AU - Lynch, Arthur E.
AU - Davies, Robert W.
AU - Jakeman, Philip M.
AU - Locke, Tim
AU - Allardyce, Joanna M.
AU - Carson, Brian P.
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/10
Y1 - 2021/10
N2 - This study aimed to investigate the test-retest reliability of peak force in the isometric squat across the strength spectrum using coefficient of variation (CV) and intra-class correlation coefficient (ICC). On two separate days, 59 healthy men (mean (SD) age 23.0 (4.1) years; height 1.79 (0.7) m; body mass 84.0 (15.2) kg) performed three maximal effort isometric squats in two positions (at a 120◦ and a 90◦ knee angle). Acceptable reliability was observed at both the 120◦ (CV = 7.5 (6.7), ICC = 0.960 [0.933, 0.977]) and 90◦ positions (CV = 9.2 (8.8), ICC = 0.920 [0.865, 0.953]). There was no relationship between peak force in the isometric squat and the test-retest reliability at either the 120◦ (r = 0.052, p = 0.327) or 90◦ (r = 0.014, p = 0.613) positions. A subgroup of subjects (n = 17) also completed the isometric squat test at a 65◦ knee angle. Acceptable reliability was observed in this position (CV = 9.6 (9.3), ICC = 0.916 [0.766, 0.970]) and reliability was comparable to the 120◦ and 90◦ positions. Therefore, we deem isometric squat peak force output to be a valid and reliable measure across the strength spectrum and in different isometric squat positions.
AB - This study aimed to investigate the test-retest reliability of peak force in the isometric squat across the strength spectrum using coefficient of variation (CV) and intra-class correlation coefficient (ICC). On two separate days, 59 healthy men (mean (SD) age 23.0 (4.1) years; height 1.79 (0.7) m; body mass 84.0 (15.2) kg) performed three maximal effort isometric squats in two positions (at a 120◦ and a 90◦ knee angle). Acceptable reliability was observed at both the 120◦ (CV = 7.5 (6.7), ICC = 0.960 [0.933, 0.977]) and 90◦ positions (CV = 9.2 (8.8), ICC = 0.920 [0.865, 0.953]). There was no relationship between peak force in the isometric squat and the test-retest reliability at either the 120◦ (r = 0.052, p = 0.327) or 90◦ (r = 0.014, p = 0.613) positions. A subgroup of subjects (n = 17) also completed the isometric squat test at a 65◦ knee angle. Acceptable reliability was observed in this position (CV = 9.6 (9.3), ICC = 0.916 [0.766, 0.970]) and reliability was comparable to the 120◦ and 90◦ positions. Therefore, we deem isometric squat peak force output to be a valid and reliable measure across the strength spectrum and in different isometric squat positions.
KW - Isometric contraction
KW - Measurement
KW - Muscle strength
KW - Reproducibility of results
KW - Strength testing
UR - http://www.scopus.com/inward/record.url?scp=85117295376&partnerID=8YFLogxK
U2 - 10.3390/sports9100140
DO - 10.3390/sports9100140
M3 - Article
AN - SCOPUS:85117295376
SN - 2075-4663
VL - 9
JO - Sports
JF - Sports
IS - 10
M1 - 140
ER -