title: Effect of time of day on the vertical spinal creep response.
abstract: Vertical spinal creep (VSC) is height loss during sustained postures over a set period of time. While total stature has been demonstrated to decrease throughout the day, whether a diurnal effect applies to the VSC response has not been reported. The aim of this study was to investigate whether time of day had an effect on the magnitude of the VSC response in young subjects asymptomatic for musculoskeletal pathologies. The VSC response was recorded over 25 min while subjects remained seated on the stadiometer, at three times (morning, midday and afternoon) on the same day, in 48 asymptomatic volunteers aged 20-39 years. While no significant differences were calculated for the magnitude of the VSC responses on the three occasions of testing, differences in magnitude of VSC response may have been confounded by preloading activities. Where magnitude of the VSC response is the primary outcome measure, measurement protocols should control preloading activities and continue to conduct measurements at the same time of day, until further studies conclusively refute the existence of a diurnal effect.
authors.affiliation: School of Health Sciences, University of South Australia, City East Campus, North Terrace, Adelaide 5000, South Australia.
authors.forename: Rungthip
authors.initials: R
authors.lastname: Puntumetakul
authors.forename: Patricia
authors.initials: P
authors.lastname: Trott
authors.forename: Marie
authors.initials: M
authors.lastname: Williams
authors.forename: Ian
authors.initials: I
authors.lastname: Fulton
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001827:Body Height / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000503:physiopathology; D008297:Male; D009141:Musculoskeletal System; D010865:Pilot Projects; D011187:Posture; D011446:Prospective Studies; D013131:Spine / Q000502:physiology*; D013997:Time Factors; D016474:Weight-Bearing / Q000502:physiology