Vertical Ground Reaction Force During a Water-Based Exercise Performed by Elderly Women: Equipment Use Effects

Magnitude of vertical ground reaction force during water-based exercises in women with obesity

Individuals with obesity are recommended to practice physical activity with reduced weight bearing, such as water-based exercises. However, the magnitude of the vertical ground reaction force (Fz) during these exercises is unknown in this population. This study aimed to verify the magnitude of peak Fz (Fzpeak) in women with obesity during different exercises performed in water and on land and at different intensities. Ten adult women with obesity class 1 (body mass index: 31.6 ± 0.57 kg·m-2) completed two randomised sessions, one performed on land and other in water, composed by three exercises (stationary running, frontal kick, butt kick) performed at cadences of 80 b·min-1, 100 b·min-1 and maximal. Fzpeak value was determined in each situation. Data were analysed using repeated-measures three-way ANOVA (α = 0.05). Significant lower Fzpeak values were observed in water (p < 0.001), with no significant differences between the exercises. A significant difference in the Fzpeak was verified between maximal cadence and 80 b·min-1 (p = 0.01). Water-based exercises performed by women with obesity revealed a Fzpeak reduction from land to water corresponding to 41-67%. Also, the three water-based exercises resulted in similar Fzpeak values, while an increase was observed 80 b·min-1 to the maximal cadence.

Aquatic Exercise on Brain Activity in Type 2 Diabetic: Randomized Clinical Trial

BACKGROUND

A water-based physical exercise program is extremely important for the rehabilitation of type 2 diabetes. Little is known about its action on cerebral electrical activity.

OBJECTIVE

To evaluate the effect of a water-based physical exercise protocol on electroencephalographic activity, blood glucose levels, and functional capacity, as well as their correlation, in type 2 diabetics.

METHODS

Study design: Randomized Clinical Trial. Forty volunteers were randomized into two groups: control (n = 20) and study (n = 20). A water-based physical exercise program comprising 50 min sessions was conducted three times a week for five weeks. Assessments were performed at the pre- and post-intervention and follow-up phases. The qualitative data were compared using the Mann-Whitney test and Chi-Square. Quantitative data were compared using the Kruskal-Wallis, Independent t, and ANOVA mixed tests. The Spearman correlation coefficient was used to correlate the data.

RESULTS

The data were similar when comparing the groups. Six-minute walk test data increased in the comparison between times (p = 0.01-PrexPos). EEG data decreased in comparison between times (prexfollow-up-p < 0.05), except AF3. EEG data decreased in the timexgroup comparison (prexfollow-up and postxfollow-up-p < 0.05).

CONCLUSIONS

The water-based exercise protocol maintained electroencephalographic activity, glucose levels, and functional capacity in people with type 2 diabetes, and there was no relationship between brain electrical activity and capillary blood glucose.

Force Production and Coordination from Older Women in Water Fitness Exercises

The aim of this study was to compare bilateral propulsive forces and coordination while exercising at static and dynamic conditions in the water. A total of 27 older women (age: 65.1 ± 6.7 years old) performed the following exercises: (i) horizontal upper-limbs adduction (HA; static condition) and (ii) rocking horse (RH; dynamic condition) through an incremental protocol with music cadences from 105 up to 150 b·min⁻¹. The duration of each trial was set at 30 second (sec). Propulsive peak force (in Newton, N) of dominant (PF_D) and nondominant (PF_ND) upper limbs was retrieved using hand sensors coupled to a differential pressure system. Significant differences in force production were found between static and dynamic exercises at higher cadences (120, 135, and 150 b·min⁻¹). The static condition elicited higher bilateral propulsive forces and a more symmetric pattern. The in-water static exercise with bilateral action from the upper limbs proved to be the most appropriate strategy for older women to work strength and to reduce asymmetries.

Kinetic parameters during land and water walking performed by individuals with Down Syndrome

BACKGROUND

Down Syndrome (DS) is a genetic condition presenting delay in acquisition of main motor milestones, such as walking. Although studies have been investigating the biomechanical parameters during land walking performed by individual with DS, the literature is scarce regarding kinetic parameters analysis in this population, specially during water walking.

RESEARCH QUESTION

This study sought to assess the vertical ground reaction force (Fz) of walking performed in water and on land at different speeds by individuals with DS.

METHODS

Fourteen adults with DS (age: 27.9 ± 7.9 years; body mass: 58.4 ± 12.9 kg; height: 1.4 ± 0.1 m, body mass index: 29.2 ± 5.4 kg.m^-2) completed two sessions of data collection, one on land and another in aquatic environment. The protocol consisted of walking performed at three self-selected speeds (slow, comfortable and fast) in randomized order. The Fz was assessed with a waterproof force plate in each condition. Two-way repeated-measures ANOVA (environment and speed), with Bonferroni's post hoc tests, were used for analysis. A significance level was set as α = 0.05.

RESULTS

Significant differences were observed between environments (p < 0.001), with reduced first peak of Fz (68-73%), second peak of Fz (66-70%), loading rate (75-78%) and impulse (40-41%) in the water walking for all speeds analyzed. In the aquatic environment, no significant difference was observed for the first and second Fz peaks with the increasing speed of walking. Moreover, the loading rate significantly increased (p = 0.019) as the impulse significantly reduced (p < 0.001) in the higher speeds.

SIGNIFICANCE

Individuals with DS present reduced Fz outcomes during water walking in comparison to land. Therefore, water walking may be performed by individuals with DS with safe vertical loads on lower limbs regardless the self-selected speed for rehabilitation, correction of gait and training purposes.