Quality of life responses after combined and aerobic water-based training programs in older women: a randomized clinical trial (ACTIVE Study).

BACKGROUND: Quality of life (QoL) is an important health index for older adults. AIM: The aim of this study was to compare the effects of 16 weeks of aerobic training to 8 weeks of aerobic followed by 8 weeks of combined (i.e., resistance and aerobic exercises) training, as well as to a control group on the QoL of older women exercising in the aquatic environment. METHODS: 52 older women were first randomized to either aerobic training (n = 35) or a control group (n = 17). After 8 weeks of intervention, participants initially assigned to the aerobic training group were again randomized to either 8 additional weeks of aerobic (n = 17) or combined training (n = 18). Aerobic training was performed at the heart rate percentage associated with the anaerobic threshold, while resistance training sets were performed at maximal effort. The control group performed low-intensity water-based therapeutic exercises. QoL was assessed before (week 0) and after the intervention (week 17) using the WHOQOL-BREEF and WHOQOL-OLD questionnaires. Generalized Estimating Equations (GEE) and Bonferroni post hoc tests (α = 0.05) were used to compare time points and groups. RESULTS: QoL improved significantly only in the training groups after the 16-week training intervention, whereas it remained unchanged in the control group. In addition, autonomy, environment, and present, past and future activities domains were more impacted after combined training. CONCLUSION: QoL improved only in the water-based training groups, and the addition of resistance exercises to the training program resulted in additional benefits to autonomy, environment, and past, present, and future activities domains. TRIAL REGISTRATION: Clinical Trials NCT03892278.

Exercise intervention does not reduce the likelihood of VO2max underestimation in older adults with hypertension.

The present study aimed to investigate whether training status would influence the capacity of a verification phase (VER) to confirm maximal oxygen uptake (VO2max) of a previous graded exercise test (GXT) in individuals with hypertension. Twelve older adults with hypertension (8 women) were recruited. Using a within-subject design, participants performed a treadmill GXT to exhaustion followed by a multistage VER both before and after a 12-wkcombined exercise training programme. Individual VO2max, respiratory exchange ratio (RER), maximal heart rate (HRmax), and rating of perceived exertion (RPE) were measured during both GXT and VER tests. Absolute and relative VO2max values were higher in VER than in GXT at baseline, but only absolute VO2max differed between bouts post-intervention (all p < 0.05). Individual VO2max comparisons revealed that 75% of the participants (9/12) achieved a VO2max value that was ≥3% during VER both before (range: +4.9% to +21%) and after the intervention (range: +3.4% to +18.8%), whereas 91.7% (11/12) of the tests would have been validated as a maximal effort if the classic criteria were employed. A 12-wk combined training intervention could not improve the capacity of older adults with hypertension to achieve VO2max during a GXT, as assessed by VER.

Reliability of a smartphone application to measure physical activity.

The aim of this study was to evaluate how accurate is a smartphone app to measure a physical activity parameter (steps). Physical Education undergraduate students (n = 46), both male and female, were recruited. A tally counter, a validated device (Xiaomi Mi Band 2®) and My Active Life app were used to perform the steps count. Each participant took three low-intensity treadmill walks (5 km h-1), with a number of target steps (500-, 1000- and 1500-steps walk). Visual agreement analyses was performed through Bland-Altman plots. There was no significant interaction between steps walks and device during treadmill walking test (F(2,84) = 3.854; p = 0.07). Differences in steps measured by Mi Band were not different from 0 in 500-steps walk (p = 0.243) and 1000-steps walk (p = 0.350), and in My Active Life in 500-steps walk (p = 0.177) and 1500-steps walk (p = 0.221). Bland-Altman analyses indicated an acceptable agreement between My active Life app and Mi Band devices for 1000-steps walk (-359.01; 310.43) and 1500-steps walk (-572.97; 377.11). In conclusion, My Active Life app showed accuracy in measuring total steps, in longer walking activities (e.g. higher than 1000 steps), and can be used on a daily basis and in research setting.

Anaerobic Threshold in a Water-Based Exercise: Agreement Between Heart Rate Deflection Point and Lactate Threshold Methods.

ABSTRACT: Alberton, CL, Andrade, LS, Pinheiro, RB, and Pinto, SS. Anaerobic threshold in a water-based exercise: agreement between heart rate deflection point and lactate threshold methods. J Strength Cond Res 35(9): 2472-2478, 2021-The purpose of this study was to compare and assess the agreement of the heart rate (HR) and rating of perceived exertion (RPE) corresponding to the anaerobic threshold (AT) between HR deflection point (HRDP) and lactate threshold (LT) methods during a water-based exercise in young men. Sixteen young men (24 ± 6 years) performed the experimental protocol, which comprised the performance of a maximal incremental test during the water-based stationary running exercise. The initial cadence corresponded to 90 b·min-1, with 10 b·min-1 increases every 3 minutes up to exhaustion. Heart rate was monitored every 30 seconds while blood lactate concentrations and RPE were measured at the end of each 3-minute bout. Anaerobic threshold was identified by HRDP and LT methods by experienced physiologists. Paired Student's t-test, Bland-Altman analysis, and Pearson correlation were used for data analysis (α = 0.05). As results, there was agreement between HRDP and LT methods for HR, while RPE presented significant higher values for the HRDP method, resulting in an absence of acceptable agreement between methods. In addition, strong relationships (p ≤ 0.001) were verified between methods of AT determination for HR (r = 0.786) and RPE (r = 0.916). Therefore, based on the agreement between HRDP and LT methods, the HR determined by HRDP may be a valid parameter used for the intensity prescription of water-based stationary running exercise in young men during water aerobics programs and may be considered more reliable than RPE.

Whole-Body High-Intensity Interval Training Induce Similar Cardiorespiratory Adaptations Compared With Traditional High-Intensity Interval Training and Moderate-Intensity Continuous Training in Healthy Men.

Schaun, GZ, Pinto, SS, Silva, MR, Dolinski, DB, and Alberton, CL. Sixteen weeks of whole-body high-intensity interval training induce similar cardiorespiratory responses compared with traditional high-intensity interval training and moderate-intensity continuous training in healthy men. J Strength Cond Res 32(10): 2730-2742, 2018-Low-volume high-intensity interval training (HIIT) protocols that use the body weight as resistance could be an interesting and inexpensive alternative to traditional ergometer-based high-intensity interval training (HIIT-T) and moderate-intensity continuous training (MICT). Therefore, our aim was to compare the effects of 16 weeks of whole-body HIIT (HIIT-WB), HIIT-T, and MICT on maximal oxygen uptake (V[Combining Dot Above]O2max), second ventilatory threshold (VT2), and running economy (RE) outcomes. Fifty-five healthy men (23.7 ± 0.7 years, 1.79 ± 0.01 m, 78.5 ± 1.7 kg) were randomized into 3 training groups (HIIT-T = 17; HIIT-WB = 19; MICT = 19) for 16 weeks (3× per week). The HIIT-T group performed eight 20-second bouts at 130% of the velocity associated to V[Combining Dot Above]O2max (vV[Combining Dot Above]O2max) interspersed by 10-second passive recovery on a treadmill, whereas HIIT-WB group performed the same protocol but used calisthenics exercises at an all-out intensity instead of treadmill running. Finally, MICT group exercised for 30 minutes at 90-95% of the heart rate (HR) associated to VT2. After the intervention, all groups improved V[Combining Dot Above]O2max, vV[Combining Dot Above]O2max, time to exhaustion (Tmax), VT2, velocity associated with VT2 (vVT2), and time to reach VT2 (tVT2) significantly (p < 0.05). Moreover, Tmax, vVT2, and tVT2 were greater after HIIT-T compared with HIIT-WB (p < 0.05), whereas oxygen uptake increased and HR decreased during the RE test in all groups (p < 0.05). Our results demonstrate that HIIT-WB can be as effective as traditional HIIT while also being time-efficient compared with MICT to improve health-related outcomes after 16 weeks of training. However, HIIT-T and MICT seem preferable to enhance performance-related outcomes compared with HIIT-WB.

HR, ̇V̇O2, and RPE Relationships in an Aquatic Incremental Maximum Test Performed by Young Women.

David, GB, Andrade, LS, Schaun, GZ, and Alberton, CL. HR, V̇O2, and RPE relationships in an aquatic incremental maximum test performed by young women. J Strength Cond Res 31(10): 2852-2858, 2017-The purpose of the study was to verify the relationship between oxygen uptake (V̇O2), heart rate (HR), rate of perceived exertion (RPE), and cadence (CAD) in an aquatic incremental maximum test performed during a water-based stationary running exercise. The study also verified the best adjustments for these relationships (linear or polynomial). Thirteen young college women (mean ± SD: 23.15 ± 1.72 years, 21.43 ± 2.09 body mass index) participated in the study. They performed an aquatic incremental maximum test during a water-based stationary running exercise. The experimental protocol started at an initial CAD of 80 b·min, and it was followed by increases of 10 b·min every minute until exhaustion. V̇O2, HR, and RPE were measured along the test. Linear and polynomial regression analysis were performed to determine the relationship among the percentage of peak V̇O2 (%V̇O2peak), percentage of maximal HR (%HRmax), RPE, and CAD to determine the best adjustment for each analysis (α = 0.05). The polynomial regression showed the best adjustments for all analysis. Data revealed a significant relationship (p < 0.001) between %V̇O2peak and %HRmax (r = 0.858), %HRmax and RPE (r = 0.823), and %V̇O2peak and RPE (r = 0.871). Regarding the relationship between these above-mentioned variables and CAD, all of them were significant (p < 0.001), with r = 0.848 for CAD and %HRmax, r = 0.877 for CAD and %V̇O2peak and r = 0.878 for CAD and RPE. It was concluded that all analyzed variables are associated and their relationships are in a polynomial quadratic form. Based on the findings, instructors may use the positive relationships between %V̇O2peak, %HRmax, and RPE to efficiently prescribe water-based training sessions.

Noninvasive Determination of Anaerobic Threshold Based on the Heart Rate Deflection Point in Water Cycling.

This study compared heart rate (HR), oxygen uptake (VO2), percentage of maximal HR (%HRmax), percentage of maximal VO2, and cadence (Cad) related to the anaerobic threshold (AT) during a water cycling maximal test between heart rate deflection point (HRDP) and ventilatory (VT) methods. In addition, the correlations between both methods were assessed for all variables. The test was performed by 27 men in a cycle ergometer in an aquatic environment. The protocol started at a Cad of 100 b · min(-1) for 3 minutes with subsequent increments of 15 b · min(-1) every 2 minutes until exhaustion. A paired two-tailed Student's t-test was used to compare the variables between the HRDP and VT methods. The Pearson product-moment correlation test was used to correlate the same variables determined by the 2 methods. There was no difference in HR (166 ± 13 vs. 166 ± 13 b · min(-1)), VO2 (38.56 ± 6.26 vs. 39.18 ± 6.13 ml · kg(-1) · min(-1)), %HRmax (89.24 ± 3.84 vs. 89.52 ± 4.29%), VO2max (70.44 ± 7.99 vs. 71.64 ± 8.32%), and Cad (174 ± 14 b · min(-1) vs. 171 ± 8 b · min(-1)) related to AT between the HRDP and VT methods. Moreover, significant relationships were found between the methods to determine the AT for all variables analyzed (r = 0.57-0.97). The estimation of the HRDP may be a noninvasive and easy method to determine the AT, which could be used to adapt individualized training intensities to practitioners during water cycling classes.

Water-Based Concurrent Training Improves Peak Oxygen Uptake, Rate of Force Development, Jump Height, and Neuromuscular Economy in Young Women.

The study investigated the effects of different intrasession exercise sequences on the cardiorespiratory and neuromuscular adaptations induced by water-based concurrent training in young subjects. Twenty-six healthy young women (25.1 ± 2.9 years) were placed into 2 water-based concurrent training groups: resistance before (RA, n = 13) or after (AR, n = 13) aerobic training. Subjects trained resistance and aerobic training during 12 weeks, 2 times per week performing both exercise types in the same training session. Peak oxygen uptake (V[Combining Dot Above]O2peak), rate of force development (RFD) obtained during an isometric peak torque knee extension protocol, jump height, and neuromuscular economy (normalized electromyography at 80% of pretraining knee extension isometric peak torque) in young women were determined. After training, there was a significant increase (p < 0.001) in both RA and AR in the V[Combining Dot Above]O2peak, with no differences between groups (7 vs. 5%). The maximal isometric knee extension RFD showed significant increases (p = 0.003) after training (RA: 19 vs. AR: 30%), and both groups presented similar gains. In addition, the countermovement jump height also increased (p = 0.034) after training (RA: 5% vs. AR: 6%), with no difference between groups. After training, there were significant improvements on vastus lateralis (p < 0.001) (RA: -13% vs. AR: -20%) and rectus femoris (p = 0.025) (RA: -17% vs. AR: -7%) neuromuscular economy, with no difference between groups. In conclusion, 12 weeks of water-based concurrent training improved the peak oxygen uptake, RFD, jump height, and neuromuscular economy in young women independent from the intrasession exercise sequence.

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

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 (VO2), 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 (α = 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. VO2 and VE had similar values across the 4 protocols at the VT1 intensity, but significantly higher values were observed with TL (VO2: p < 0.001; VE: p < 0.001) at the VT2 intensity. At the MAX intensity, VO2 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.

Maximal and ventilatory thresholds of oxygen uptake and rating of perceived exertion responses to water aerobic exercises.

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 α = 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.

Cardiorespiratory responses to stationary running in water and on land.

The aim of the study was to compare maximal and submaximal cardiorespiratory responses between progressive tests on a treadmill on land (TRE), and stationary running on land (SRL) and in water (SRW), while also comparing two methods of determining the second turn point (ST) (ventilatory curve and heart rate deflection point). The study sample consisted of nine active women (23 ± 1.94 years) that performed three maximal protocols in separate days. Heart rate (HR) and oxygen uptake (VO2) were measured in all sessions. The data were analyzed using repeated-measures ANOVA and two-way repeated measures ANOVA with post-hoc Bonferroni test. Greater values of maximal HR (HRmax) and HR at ST (HRST) were observed during exercise performed on TRE and during the SRL, compared to the SRW (p < 0.05). The results for maximal VO2 (VO2max) and VO2 at ST (VO2ST) showed greater and significant values on TRE compared to STL and STW (p < 0.05). Furthermore, the HR and VO2 corresponding to the ST showed similar values between the two methods. Thus, the main conclusion of the present study was that the HR deflection point seems to be a simple and practical alternative method for determining the ST in all protocols analyzed. Key PointsThe maximal and submaximal (second turn point) oxygen uptake were influenced by the type of exercise, as these responses were similar in both water-based and land-based stationary running protocols and different from those obtained during the treadmill running, that presented greater values compared with both stationary running protocols.The heart rate deflection point can be used for determining the second turn point during stationary running test in aquatic environment.Caution is necessary in the interpretation of the application of the heart rate deflection point in water aerobics exercises because we analyzed only young women performing one water-based exercise.

Effect of High-Intensity Interval Treadmill Exercise on Subsequent Lower and Upper Limb Strength Performance.

Purpose: The aim of this study was to analyze the acute effect of a treadmill high-intensity interval protocol on subsequent upper body and lower body strength exercise performance. Method: Sixteen young men had their maximal aerobic capacity and one-repetition maximum (1RM) determined and underwent four randomized conditions: a half-squat control session; a bench press control session; a treadmill interval protocol followed by a half-squat experimental session; and a treadmill interval protocol followed by a bench press experimental session. During the control sessions, four sets to failure for each exercise were performed at 80% of 1RM. In the experimental sessions, participants performed eight sprints of 40 s at 100% velocity of maximal oxygen uptake with 20 s of passive interval between them, followed by the same strength exercise protocol of the control sessions. The number of repetitions during each protocol and participants' heart rate (HR),and blood lactate concentration ([lac]) were compared pre and post protocols and exercises. Results: Fewer repetitions were completed in the experimental session compared to the control sessions (p < .001). Moreover, the reduction in number of repetitions performed was more evident in half-squat compared to bench press (p = .018). HR was higher at the end of sessions with the interval protocol for both exercises (p < .001). The [lac] was higher at the end of session with the interval protocol for half-squat (p = .003). Conclusions: These findings suggest that previous high-intensity interval running may impair subsequent strength exercise performance, but the magnitude of the negative effect is greater in the lower limbs.

Chronic low back pain prevalence in Federal Highway Police Officers: A cross-sectional study.

BACKGROUND: Police officers are exposed to specific occupational tasks, which require lifting, trunk flexion and rotation, carrying weight, and frequent standing periods, which may be associated with an increased risk of experiencing low back pain (LBP). OBJECTIVE: To describe the prevalence and intensity of chronic LBP (CLBP) in Brazilian Federal Highway Police officers (FHPO) from the Rio Grande do Sul state and evaluate its associated factors. METHODS: A total of 208 FHPOs participated in this study. The participants answered an electronic questionnaire containing sociodemographic, behavioral, and occupational questions, and CLBP history. Data analysis comprises descriptive statistics and Poisson regression models. RESULTS: Most of the FHPO were male, aged 41 or more, lived with a partner and were physically active. Sixty-seven percent of FHPO had CLBP, and the median pain intensity was 3.0 (IQR = 0- 5). Participants who lived with a partner were less likely to report CLBP (PR = 0.80; 95% CI = 0.64; 0.99). On the other hand, those who worked as FHPO for more than 11 years were more likely to report CLPB (PR = 1.32; 95% CI = 1.06; 1.63), and high pain intensity (ß= 0.95; 95% CI = 0.19; 1.71). CONCLUSIONS: The high CLBP prevalence among FHPO from Rio Grande do Sul state indicates a need to highlight the importance for police organizations to promote CLBP prevention and implement workplace management programs.

Water-Based Training Programs Improve Functional Capacity, Cognitive and Hemodynamic Outcomes? The ACTIVE Randomized Clinical Trial.

Purpose: To compare the effects of 16 weeks of aerobic training (AT) to 8 weeks of AT followed by 8 weeks of combined training (CT), as well as to a control group (CG), on the functional, cognitive and hemodynamic responses of older women exercising in the aquatic environment. Materials and Methods: The study is a three-armed parallel randomized controlled clinical trial. For this, 52 older women were first randomized in an aerobic training (AT; n = 35) or control group (CG; n = 17). After 8 weeks of intervention, participants from AT group were again randomized into another 8-week period of either AT (n = 17) or combined training (CT; n = 18). AT was performed at the percentage of the heart rate corresponding to the anaerobic threshold, resistance training was performed with sets at maximal effort and the control group performed low-intensity therapeutic exercises in water. All outcomes were assessed before (week 0) and after the intervention (week 17). In addition, some outcomes were also investigated in the middle timepoint (week 9). Generalized Estimating Equations (GEE) and Bonferroni post-hoc tests (α = 0.05) were used to compare timepoints and groups. Results: All groups similarly improved functional capacity (3-11%) and blood pressure (-4 to -10%), whereas cognitive function was not modified for any group. Conclusion: Water-based training programs and therapeutic exercises (i.e., CG) improve functional capacity and blood pressure responses in older women. Clinical Trials NCT03892278.

Effectiveness of m-health-based core strengthening exercise and health education for public safety workers with chronic non-specific low back pain: study protocol for a superiority randomized controlled trial (SAFEBACK).

BACKGROUND: Low back pain (LBP) is the leading cause of years lived with disability worldwide. Public safety workers are highly exposed to physically demanding activities and inappropriate postures, increasing the risk of experiencing LBP. Smartphone app-based self-managed interventions may be an alternative for chronic non-specific LBP (CNSLBP) treatment. This study aims to evaluate the effectiveness of a smartphone app-based self-managed exercise program plus health education, compared to a health education program alone, on neuromuscular and perceptual outcomes in police officers and firefighters with CNSLBP. METHODS: This is a parallel, two-armed, blinded evaluator randomized clinical trial. Police officers and firefighters (from public safety institutions in the Rio Grande do Sul state, Brazil) will be randomly assigned to a m-health self-managed exercise program (twice a week) plus health education or health education alone. Self-management exercise program components are mobility and core resistance exercises, available on the app. Follow-ups will be conducted post-treatment (8 weeks) and 16 weeks after randomization. The co-primary outcomes will be pain intensity and disability post-treatment (8 weeks). Secondary outcomes will be biopsychosocial factors related to CNSLBP. DISCUSSION: We hypothesize that the effects of a smartphone app-based self-managed exercise program on co-primary and secondary outcomes will be superior, compared to the health education only in public safety workers with CNSLBP. TRIAL REGISTRATION: The study was prospectively registered at ClinicalTrials.gov (NCT05481996. Registered on August 01, 2022).

Using Bodyweight as Resistance Can Be a Promising Avenue to Promote Interval Training: Enjoyment Comparisons to Treadmill-Based Protocols.

Purpose: Even though multiple training methods appear to be effective to improve cardiorespiratory fitness, they also need to be perceived as tolerable or enjoyable by exercisers to maximize long-term behavioral maintenance. Therefore, the purpose of the current study was to compare perceived enjoyment between whole-body interval training (SIT-WB), treadmill-based interval training (SIT-T) and moderate-intensity continuous training (MICT). Method: Forty-one healthy adult men (age: 23.7 ± 0.7 years, height: 1.79 ± 0.01 m, body mass: 78.5 ± 1.7 kg; VO2max: 46.7 ± 7.3 ml.kg-1.min-1) were randomly assigned to SIT-WB, SIT-T, or MICT and underwent 16 weeks of training (3x/w). SIT-WB and SIT-T completed eight 20 s bouts interspersed by 10 s passive recovery, differing as to the exercise mode performed (i.e., calisthenics exercises and treadmill running, respectively) whereas MICT participants ran for 30 min at an intensity below the second ventilatory threshold. Perceived enjoyment was assessed 10 min post-exercise at weeks 1, 5, 9, 13, and 16, using the Physical Activity Enjoyment Scale. Results: Compliance was high (~90%) across all three training groups (p = .803). All training modes were rated as enjoyable and no significant within- (F(4, 152) = 1.132, p = .344) or between-group (F(2, 38) = 0.662, p = .521) differences were found during the intervention period. Conclusions: These results suggest that SIT-WB can be employed as an enjoyable low-cost alternative to traditional treadmill-based SIT and MICT for up to 16 weeks.

Cardiorespiratory Parameters Comparison Between Incremental Protocols Performed in Aquatic and Land Environments by Healthy Individuals: A Systematic Review and Meta-Analysis.

BACKGROUND: Physical properties of water cause physiological changes in the immersed human body compared with the land environment. Understanding the magnitude of cardiorespiratory alterations might ensure adequate intensity control during aquatic exercise programs. OBJECTIVE: We aimed to compare the oxygen uptake (VO2), heart rate (HR), and rating of perceived exertion (RPE) parameters during aquatic and land incremental tests. METHODS: Four databases (PubMed, LILACS, EMBASE, and SPORTDiscus) were searched in September 2020. Eligibility criteria included studies in a crossover design comparing aquatic and land incremental tests for healthy individuals with at least one of the following parameters: VO2 (maximal, VO2max; anaerobic threshold, VO2AT), HR (HRmax; HRAT), and RPE (RPEmax; RPEAT). The random-effects meta-analysis included mean difference and 95% confidence interval for VO2 and HR or standardized mean difference for RPE. The Joanna Briggs Institute Critical Appraisal tool was adapted to assess methodological quality. RESULTS: Twenty-eight studies were eligible and included in the meta-analysis. Aquatic protocols showed lower values compared with land for VO2max (- 7.07 mL.kg-1.min-1; - 8.43 to - 5.70; n = 502), VO2AT (- 6.19 mL.kg-1.min-1; - 7.66 to - 4.73; n = 145), HRmax (- 11.71 bpm; - 13.84 to - 9.58; n = 503), and HRAT (- 15.29 bpm; - 19.05 to - 11.53; n = 145). RPEmax (0.01; - 0.16 to 0.18; n = 299) and RPEAT (- 0.67; - 1.35 to 0.02; n = 55) values were similar between aquatic and land protocols. CONCLUSIONS: Our study reinforces the specificity of the environment during incremental tests for prescribing exercises based on physiological parameters as VO2 and HR parameters presented lower values in aquatic protocols than land protocols. Conversely, RPE seems an interchangeable measure of exercise intensity, with similar values during the protocols in both environments. Substantial levels of heterogeneity were present for the VO2max and HRmax meta-analyses, and as such, results should be interpreted with attention. PROTOCOL REGISTRATION: This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42020212508).

Aerobic and combined water-based trainings in older women: effects on strength and cardiorespiratory outcomes.

BACKGROUND: The aim of the present study was to investigate the muscular and cardiorespiratory adaptations of two water-based training programs in older women. METHODS: Volunteers were divided between a water-based aerobic training (WBA; N.=13), water-based combined training (WBC; N.=11) or an active control group (CG; N.=9) and those assigned to WBA and WBC exercised twice a week for 12 weeks. All outcomes of interest were assessed prior and after the intervention. The data were analyzed using Generalized Estimating Equations (GEE), and Bonferroni post-hoc test (α=0.05). Aerobic training was performed at the percentage of the heart rate corresponding to the anaerobic threshold and resistance training during WBC was performed with sets at maximal effort. RESULTS: Improvements were observed for the maximal knee extension dynamic strength (1RM) and oxygen uptake (VO2) corresponding to the second ventilatory threshold for both WBA and WBC (1RM: 16±12% vs. 15±16%; VO2: 20±24% vs. 23±13%, respectively), whereas VO2 peak improved in all three groups (WBA: 23±21%; WBC: 18±9%; CG: 7±16%). No increase was found for horizontal chest press 1RM (P>0.05). CONCLUSIONS: These results suggest that WBA, WBC and CG are effective to improve cardiorespiratory fitness, however, only water-based training programs (WBA and WBC) appear capable of improving the maximal strength of the lower limbs.

High-velocity resistance training mitigates physiological and functional impairments in middle-aged and older adults with and without mobility-limitation.

The aim of the present study was to compare the neuromuscular, morphological, and functional responses to a high-velocity resistance training (HVRT) program between three cohorts: middle-aged adults (40-55 years, n = 18), healthy older adults (> 60 years, n = 18), and mobility-limited older adults (n = 8). Participants were tested before and after a 4-week control period and then assigned to a 12-week HVRT intervention. Investigated outcomes included ultrasound-derived muscle thickness and quality, maximal dynamic strength (1RM), maximal voluntary isometric contraction (MVIC), and muscle activation (sEMG), as well as muscle power and functional performance. After the intervention, quadriceps muscle thickness, 1RM, and sEMG improved in all three groups (all p < 0.05), whereas muscle quality improved only in middle-aged and older participants (p ≤ 0.001), and MVIC only in middle-aged and mobility-limited older adults (p < 0.05). With a few exceptions, peak power improved in all groups from 30-90% 1RM (p < 0.05) both when tested relative to pre-training or post-training 1RM workloads (all p < 0.05). Both mobility-limited older adults and older adults improved their short physical performance battery score (p < 0.05). Chair stand, stair climb, maximal gait speed, and timed up-and-go performance, on the other hand, improved in all three groups (p < 0.05), but no change was observed for habitual gait speed and 6-min walk test performance. Overall, our results demonstrate that a HVRT intervention can build a stronger foundation in middle-aged individuals so that they can better deal with age-related impairments at the same time that it can mitigate already present physiological and functional impairments in older adults with and without mobility-limitation.

Effects of strength, endurance, and concurrent training on aerobic power and dynamic neuromuscular economy in elderly men.

The aim of this study was to investigate the effects of concurrent training on endurance capacity and dynamic neuromuscular economy in elderly men. Twenty-three healthy men (65 ± 4 years) were divided into 3 groups: concurrent (CG, n = 8), strength (SG, n = 8), and aerobic training group (EG, n = 7). Each group trained 3 times a week for 12 weeks, strength training, aerobic training, or both types of training in the same session. The maximum aerobic workload (Wmax) and peak oxygen uptake (VO2peak) of the subjects were evaluated on a cycle ergometer before and after the training period. Moreover, during the maximal test, muscle activation was measured at each intensity by means of electromyographic signals from the vastus lateralis (VL), rectus femoris (RF), biceps femoris long head, and gastrocnemius lateralis to determine the dynamic neuromuscular economy. After training, significant increases in VO2peak and Wmax were only found in the CG and EG (p < 0.05), with no difference between groups. Moreover, there was a significant decrease in myoelectric activity of the RF muscle at 50 (EG), 75 and 100 W (EG and CG) and in the VL for the 3 groups at 100 W (p < 0.05). No change was seen in the electrical signal from the lateral gastrocnemius muscle and biceps femoris. The results suggest specificity in adaptations investigated in elderly subjects, because the most marked changes in the neuromuscular economy occurred in the aerobically trained groups.