title: Vertical ground reaction force during water exercises performed at different intensities.
abstract: The aim of the present study was to compare the peak vertical ground reaction force (V-GRF(peak)) and impulse of women performing water aerobic exercises at different intensities in aquatic and dry land environments. 15 young women performed 1 session in each environment consisting of 3 water aerobic exercises (stationary running, frontal kick and cross country skiing) performed at 3 cadences (first ventilatory threshold, second ventilatory threshold and maximum effort, as determined during exercise in water) in a randomized order. 2-way and 3-way repeated measures ANOVA were used to analyze the impulse and V-GRF(peak), respectively. Significantly lower values of V-GRF(peak) and impulse (p<0.001) were observed for the aquatic environment. Significant differences were observed among all cadences for V-GRF(peak) and impulse (p<0.001) in both environments except for the V-GRF(peak) between the cadences corresponding to the second ventilatory threshold and maximum effort in the aquatic environment. In addition, significantly lower V-GRF(peak) values in the aquatic environment were found for cross country skiing compared to the other exercises (p<0.001). Thus, water exercises are safe for people that need to minimize vertical ground reaction force; however, an important issue to be considered during water aerobics training is the exercise and intensity to be prescribed.
authors.affiliation: School of Physical Education, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: C L
authors.initials: CL
authors.lastname: Alberton
authors.forename: M P
authors.initials: MP
authors.lastname: Tartaruga
authors.forename: S S
authors.initials: SS
authors.lastname: Pinto
authors.forename: E L
authors.initials: EL
authors.lastname: Cadore
authors.forename: A H
authors.initials: AH
authors.lastname: Antunes
authors.forename: P
authors.initials: P
authors.lastname: Finatto
authors.forename: L F M
authors.initials: LF
authors.lastname: Kruel
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D010101:Oxygen Consumption; D014867:Water
chemical_list: D014867:Water