title: The effect of measurement time when evaluating static muscle endurance during sustained static maximal gripping.
abstract: The purpose of this study was to examine the useful measurement time when evaluating static muscle endurance by comparing various parameters during sustained static gripping for 1, 3 and 6 min. Fifteen males (mean +/- SD age 20.8 +/- 1.3 yr, height 172.9 +/- 4.6 cm, body mass 67.7 +/- 5.7 kg) and fifteen females [mean +/- SD age 20.2 +/- 0.9 yr, height 158.5 +/- 3.2 cm, body mass 55.9 +/- 4.6 kg] volunteered to participate in this study. The subjects performed the sustained static maximal grip test with a sagittal and horizontal arm position for 1, 3 and 6 min on different days. Eleven force-time parameters were selected to evaluate static muscle endurance. The trial-to-trial reliability of each measurement time of sustained static maximal gripping was very high (rxy = 0.887-0.981 (1 min), 0.912-0.993 (3 min), 0.901-0.965 (6 min)). The errors of exertion values between trials were very small (below 10%). A significant correlation was found in the following parameters: the final strength and the exponential function between 1 min and 3 min, all parameters except for the time required to reach 80% of maximal grip, the regression coefficient at post-inflection between 3 min and 6 min, and the decreasing rate between all measurement times (1 min, 3 min, and 6 min). Significant differences between the measurement times were found in all parameters except for the time to 60, 70, and 80% force decreases, and the regression coefficient of pre-inflection. There was a tendency that the longer the measurement time, the larger the decreasing force. It is suggested that for the 6 min measurement, the subjects unconsciously restrained the maximal gripping force, influenced by a psychological factor as the pain became greater. The 1 min measurement may evaluate only the remarkable decreasing phase of the decreasing force, and not evaluate the phase of an almost steady state.
authors.affiliation: Akita Prefectural University. yamaji@fukui-nct.ac.jp
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Yamaji
authors.forename: Shinichi
authors.initials: S
authors.lastname: Demura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nagasawa
authors.forename: Masakatsu
authors.initials: M
authors.lastname: Nakada
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Kitabayashi
mesh_terms: D000328:Adult; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D013178:Sports Medicine / Q000592:standards*; D013223:Statistics as Topic; D013997:Time Factors