Amanda Haberland Antunes

Vertical ground reaction force during water exercises performed at different intensities.

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.

Correlation Between Rating of Perceived Exertion and Physiological Variables During the Execution of Stationary Running in Water at Different Cadences

Alberton, CL, Antunes, AH, Pinto, SS, Tartaruga, MP, Silva, EM, Cadore, EL, and Kruel, LFM. Correlation between rating of perceived exertion and physiological variables during the execution of stationary running in water at different cadences. J Strength Cond Res 25(1): 155-162, 2011-The purpose of the present study was to correlate the rating of perceived exertion (RPE) with cardiorespiratory and neuromuscular variables during the execution of stationary running in water at different cadences. The sample consisted of 12 apparently healthy women (age: 22.33 ± 0.57 years). During the assessment session, the subjects performed the stationary running exercise in water at 3 different cadences: 60, 80, and 100 bpm. The heart rate (HR), oxygen uptake (&OV0312;o2), ventilation (Ve), and electromyographic (EMG) signal of the vastus lateralis (VL), biceps femoris (BF), rectus femoris (RF), and semitendinosus (ST) muscles were measured during the exercise, and the overall body RPE was measured immediately following the end. Pearsons linear correlation and multiple linear regression were used, with p < 0.05. The analyses demonstrate a high and significant relationship between RPE and HR (r = 0.65; p < 0.001), RPE and %HR maximal (r = 0.65; p < 0.001), RPE and &OV0312;o2 (r = 0.60; p = 0.001), RPE and %&OV0312;o2 maximal (r = 0.71; p < 0.001), and RPE and Ve (r = 0.77; p < 0.001). However, there was no relationship between the RPE and the EMGs of the VL, BF, RF, and ST muscles. With regard to the regression, the model was significant (p < 0.001) with an r2 = 0.79, whereas the variables that explained better the RPE were %&OV0312;o2 maximal and Ve. Hence, these results suggest an association between the perception of exertion and cardiorespiratory variables, which was not the case with the neuromuscular variables evaluated in this study. Therefore, the Borg scale of RPE can be used when prescribing stationary running exercise in water for young women.

MAXIMAL AND VENTILATORY THRESHOLDS OF OXYGEN UPTAKE AND RATING OF PERCEIVED EXERTION RESPONSES TO WATER AEROBIC EXERCISES

Abstract Alberton, CL, Antunes, AH, Beilke, DD, Pinto, SS, Kanitz, AC, Tartaruga, MP, and Kruel, LFM. Maximal and ventilatory thresholds of oxygen uptake and rating of perceived exertion responses to water aerobic exercises. J Strength Cond Res 27(7): 1897–1903, 2013—This study aimed to compare the V[Combining Dot Above]O2max and first and second ventilatory threshold (1stVT and 2ndVT) V[Combining Dot Above]O2 values and rating of perceived exertion (RPE) responses of treadmill running (TR) with those of 3 water aerobic exercises: stationary running (SR), jumping jack (JJ), and forward kick (FK). Nine women (22.89 ± 1.81 years, 1.66 ± 0.07 m, 58.46 ± 4.19 kg) performed 1 maximal test session for each of the 4 exercise protocols in a randomized order to determine the V[Combining Dot Above]O2max and V[Combining Dot Above]O2 values and RPE responses corresponding with the 1stVT and 2ndVT. V[Combining Dot Above]O2 values were also expressed as a percentage of V[Combining Dot Above]O2max (%V[Combining Dot Above]O2max). A repeated measures analysis of variance and Bonferroni’s post hoc test were used, with &agr; = 0.05 denoting statistical significance. The analyses showed that the V[Combining Dot Above]O2 responses were significantly higher for TR than for the other exercises at all effort intensities (V[Combining Dot Above]O2max: p < 0.001; 1stVT and 2ndVT V[Combining Dot Above]O2: p < 0.001), followed by intermediate responses for SR and FK and lower responses for JJ. However, no significant differences between exercises for values of %V[Combining Dot Above]O2max (1stVT: p = 0.099; 2ndVT: p = 0.131) and RPE (1stVT: p = 0.275; 2ndVT: p = 0.477) were found at submaximal intensities, indicating that it is possible to achieve and maintain the same training intensity with these exercises during a typical water fitness lesson. Moreover, the RPE values obtained for the 1stVT and 2ndVT can make the prescription of intensity for these water exercises for young women more simple and practical.

Maximal and ventilatory thresholds cardiorespiratory responses to three water aerobic exercises compared with treadmill on land.

Abstract Alberton, CL, Pinto, SS, Antunes, AH, Cadore, EL, Finatto, P, Tartaruga, MP, and Kruel, LFM. Maximal and ventilatory thresholds cardiorespiratory responses to three water aerobic exercises compared with treadmill on land. J Strength Cond Res 28(6): 1679–1687, 2014—The purpose of this study was to compare the cardiorespiratory responses of young women to exercise at the first ventilatory threshold (VT1), the second ventilatory threshold (VT2), and at maximum effort (MAX) between maximal incremental tests performed using water aerobic exercises and a treadmill on land (TL). Twenty women (24.0 ± 2.5 years; 163.3 ± 6.7 cm; 60.0 ± 6.7 kg) underwent 4 maximal tests in randomized order, with a 48-hour interval between tests. Three tests involved performing water aerobic exercises (stationary running, frontal kick, and cross-country skiing) and 1 TL. Oxygen uptake (V[Combining Dot Above]O2), ventilation (VE), and heart rate were measured throughout the tests, and their values at the VT1, VT2, and MAX intensities were determined by 3 independent, experienced physiologists. Repeated measures analysis of variance with Bonferroni post hoc tests were used for comparisons between tests (&agr; = 0.05). Heart rate was significantly higher in the TL condition compared with the water aerobic exercises at the VT1 (p = 0.001), VT2 (p < 0.001), and MAX (p < 0.001) intensities. V[Combining Dot Above]O2 and VE had similar values across the 4 protocols at the VT1 intensity, but significantly higher values were observed with TL (V[Combining Dot Above]O2: p < 0.001; VE: p < 0.001) at the VT2 intensity. At the MAX intensity, V[Combining Dot Above]O2 was significantly higher with TL compared with the 3 water aerobic exercises (p < 0.001), whereas no significant differences in VE between the 4 protocols were found. These results suggest that the prescription of water aerobics classes should be based on specific maximal tests for water aerobic exercises. Training intensities could be overestimated if they were based on maximal tests on dry land.

Vertical ground reaction force responses to different head-out aquatic exercises performed in water and on dry land

Abstract The purpose was to analyse the vertical ground reaction forces (Fz) of head-out aquatic exercises [stationary running (SR), frontal kick (FK), cross-country skiing (CCS), jumping jacks (JJ), adductor hop (ADH) and abductor hop (ABH)] at two cadences in both aquatic and dry land environments. Twelve young women completed two sessions in each environment, each consisting of three exercises performed at two cadences (first and second ventilatory thresholds – C1 and C2, respectively). Two-way and three-way repeated measures analysis of variance were used to the statistical analysis. The results showed that the peak Fz and impulse were significantly lower in the aquatic environment, resulting in values from 28.2% to 58.5% and 60.4% to 72.8% from those obtained on dry land, respectively. In the aquatic environment, the peak Fz was lower and the impulse was higher at the C1 than at the C2. Furthermore, it was observed that SR and FK (0.9–1.1 BW) elicited a significantly higher peak Fz values compared to the ADH and JJ exercises (0.5–0.8 BW). It can be concluded that the aquatic environment reduces the Fz during head-out aquatic exercises. It should be noted that its magnitude is also dependent on the intensity and the identity of the exercise performed.

Oxygen Uptake, Muscle Activity and Ground Reaction Force during Water Aerobic Exercises

This study aimed to compare the oxygen uptake (VO2), the muscle activity of lower limbs, and the vertical ground reaction force (V-GRF) of women performing water aerobic exercises at different intensities. 12 young women performed the experimental protocol, which consisted of 3 water exercises (stationary running [SR], frontal kick [FK] and cross country skiing [CCS]) at 3 intensities (first and second ventilatory thresholds and maximum effort). A two-way repeated measures ANOVA was used. Regarding VO2, different responses between intensities (p<0.001) were found, and values between exercises were similar. For electromyographic activity (EMG), differences between intensities for all muscles (p<0.001) were found. Greater EMG signals were observed in the FK compared to SR for rectus femoris, semitendinosus, vastus lateralis and biceps femoris muscles (p<0.05). Regarding V-GRF, there was an increase in the V-GRF at greater intensities compared to the first ventilatory threshold (p=0.001). In addition, lower values were found during CCS compared to the SR and FK exercises (p<0.001). Thus, greater cardiorespiratory and neuromuscular responses were observed with increasing intensity. Exercises such as CCS could be used to attenuate the V-GRF; if the purpose is to reduce the muscular activity of lower limbs at a specific intensity, SR could be recommended.

Rating of perceived exertion in maximal incremental tests during head-out water-based aerobic exercises

ABSTRACT The present study aimed to assess the relationship between rating of perceived exertion (RPE) and percentage of peak oxygen uptake () during three head-out water-based aerobic exercises. In addition, the RPE at the second ventilatory threshold (VT2) was also compared among them. Twenty young women performed head-out water-based maximal tests for the exercises stationary running (SR), frontal kick (FK) and cross-country skiing (CCS). RPE was monitored during the tests and the values corresponding to VT2 and training zones corresponding to 50–59%, 60–69%, 70–79%, 80–89% and were determined. Regression analysis, descriptive statistics and ANOVA with repeated measures were used. Significant relationships were observed between the RPE and (r = 0.858–0.893; P < 0.001) for all head-out water-based aerobic exercises. Average RPE ranged from 12.1–12.7 in the training zone corresponding to 50–59%, from 13.7–14.8 to 60–69%, from 15.8–16.4 to 70–79%, from 17.3–18.1 to 80–89% and from 18.5–18.9 to . No significant differences were found among the three head-out water-based aerobic exercises at VT2 (P > 0.05; SR: 16.1 ± 0.9, FK: 16.7 ± 1.5, CCS: 15.9 ± 1.3). The results support the use of RPE to control the relative intensity of training during head-out water-based aerobic exercises and indicate values near to 16–17 when targeting VT2 intensity for young women.

Active Female Maximal and Anaerobic Threshold Cardiorespiratory Responses to Six Different Water Aerobics Exercises

Purpose: Maximal tests conducted on land are not suitable for the prescription of aquatic exercises, which makes it difficult to optimize the intensity of water aerobics classes. The aim of the present study was to evaluate the maximal and anaerobic threshold cardiorespiratory responses to 6 water aerobics exercises. Volunteers performed 3 of the exercises in the sagittal plane and 3 in the frontal plane. Method: Twelve active female volunteers (aged 24 ± 2 years) performed 6 maximal progressive test sessions. Throughout the exercise tests, we measured heart rate (HR) and oxygen consumption (VO2). We randomized all sessions with a minimum interval of 48 hr between each session. For statistical analysis, we used repeated-measures 1-way analysis of variance. Results: Regarding the maximal responses, for the peak VO2, abductor hop and jumping jacks (JJ) showed significantly lower values than frontal kick and cross-country skiing (CCS; p < .001; partial η2 = .509), while for the peak HR, JJ showed statistically significantly lower responses compared with stationary running and CCS (p < .001; partial η2 = .401). At anaerobic threshold intensity expressed as the percentage of the maximum values, no statistically significant differences were found among exercises. Conclusion: Cardiorespiratory responses are directly associated with the muscle mass involved in the exercise. Thus, it is worth emphasizing the importance of performing a maximal test that is specific to the analyzed exercise so the prescription of the intensity can be safer and valid.

Horizontal ground reaction forces to stationary running performed in the water and on dry land at different physiological intensities

Abstract The aim of the present study was to compare the peak anterior–posterior (Fy) and medio–lateral (Fx) ground reaction forces (GRFs) of women performing stationary running at different intensities in aquatic and dry land environments. Fourteen young women performed the stationary running exercise at three cadences (first ventilatory threshold, second ventilatory threshold and maximum effort, as determined during exercise in water) in aquatic and dry land environments. Two-way repeated measures ANOVA was used to analyse the data (α = .05). As a result, significantly lower peak Fy anterior, Fy posterior, Fx medial and Fx lateral values were observed for the aquatic environment, except for the Fy posterior at the first ventilatory threshold. Significant differences were observed between cadences in the peak Fy anterior, Fy posterior, Fx medial and Fx lateral values, with higher values for the cadence corresponding to maximum effort compared to the first ventilatory threshold, except for the Fy posterior and Fx medial in the aquatic environment. The results indicate that the horizontal GRFs are reduced in the aquatic environment and depend on the intensity of stationary running exercise performance.