Effects of post-aquatic exercise hypotension in older adults: a systematic review with meta-analysis

doi:10.21203/rs.3.rs-4364104/v1

Download PDF

Article

Effects of post-aquatic exercise hypotension in older adults: a systematic review with meta-analysis

https://doi.org/10.21203/rs.3.rs-4364104/v1

This work is licensed under a CC BY 4.0 License

You are reading this latest preprint version

The effects of aquatic exercise on acute blood pressure (BP) responses in older population remain inconsistent. The objective was to review the literature on the effects of aquatic exercises performed in a vertical position on acute BP responses after exercise in the older adults. We conducted a systematic review and meta-analysis of clinical trials, published until August 2023, using digital databases (EMBASE, PUBMED, Lilacs, SPORTDiscus, and Web of Science). Eight studies with 197 individuals were included for qualitative analysis, and seven studies were included in the meta-analysis. The aquatic exercise reduced systolic blood pressure (SBP) by -6.86 mmHg within 1 hour and by -4.14 mmHg for 24 hours post-exercise. However, it did not affect diastolic blood pressure (DBP) responses. Furthermore, subgroup analysis showed that HIIE reduced SBP by -15.50 mmHg and DBP by -5.97 mmHg after the sessions. Already the moderate-intensity continuous exercise reduced SBP by -4.91 mmHg, with no effect on DBP up to 1 hour after the sessions. Subgroup analysis over 24 hours was not possible. Acute aquatic exercise can reduce BP in the older adults, especially SBP. Post-exercise BP reduction is of utmost importance for the older people in preventing cardiovascular diseases, such as arterial hypertension.

Health sciences/Diseases/Cardiovascular diseases/Hypertension

Health sciences/Health care/Geriatrics

Exercise

Arterial Pressure

Post-Exercise Hypotension

Aged

Aging is a natural, dynamic, and progressive process. It is marked by various morphological, functional, biochemical, and psychological changes that lead to increased vulnerability and a higher incidence of chronic diseases such as arterial hypertension (AH)¹. According to the World Health Organization, AH affects 1.28 million adults aged 30–79 worldwide². Characterized as a typically asymptomatic condition, AH can be influenced by various factors (genetics, ethnicity, sedentary lifestyle, age, among others) and involves alterations in the renin-angiotensin-aldosterone system, cardiac autonomic regulation and other systems that control vascular function³. Thus, it is a significant risk factor for cardiovascular mortality, especially in older adults⁴.

According to the American Heart Association and the American College of Cardiology, lifestyle modifications, such as increasing physical activity levels and regular exercise, are considered primary approaches for the prevention and treatment of AH⁵. In fact, the literature shows that regular physical exercise leads to a significant chronic reduction in blood pressure (BP) values^6,7.

Different exercise sessions are studied due to post-exercise hypotension (PEH), characterized by reduced BP values below pre-exercise resting levels and levels observed after a session without physical exercise⁸. The cumulative effect of this acute hypotensive response may lead to a chronic effect, which can be highly beneficial to the individual's health⁹.

In this context, a meta-analysis demonstrated that exercise sessions on land, whether aerobic or strength training, reduce systolic blood pressure (SBP) values by 6 and 3 mmHg, respectively, and diastolic blood pressure (DBP) values by 4 and 3 mmHg, respectively⁹. The effects of aquatic training also show benefits in SBP responses in adults and older adults¹⁰.

Interest in the study of aquatic exercise has gained prominence, mainly due to the specific characteristics of this environment, such as buoyancy, which reduces joint impact, a crucial feature, particularly for older persons¹¹. Additionally, water immersion induces a range of physiological adjustments, including increased diuresis, lower peripheral resistance, suppression of sympathetic activity, and reduced BP and heart rate values¹².

In this regard, the literature also focuses on BP responses following aquatic exercise sessions^13–16. However, the results found still appear divergent, as some studies show significant reductions after moderate-intensity water aerobics sessions^13,16, while another study demonstrates the maintenance of BP values¹⁴.

A meta-analysis evaluated BP responses in hypertensive individuals (> 18 years) after aquatic exercise compared to a control condition (land-based exercise or rest) and found no differences in 24-hour responses between the sessions. However, SBP and DBP decreased during the night period (8,6 mmHg and 3,7 mmHg, respectively) compared to land-based exercise, and DBP showed a significant reduction (1.7 mmHg) after aquatic exercise versus rest¹⁷. It is known that methodological differences can influence these results, such as the studied population, the exercise session protocol, and the comparison between land and water exercise sessions. Therefore, there is currently no meta-analysis in the literature on the effects of a single aquatic exercise session versus a control session (no exercise) on the BP of older adult individuals.

Given this scenario, it is crucial to emphasize the importance of analyzing the present data in the literature regarding the effects of an aquatic exercise session on BP. Older people are the population at the highest risk for developing hypertension and constitute the primary audience for water aerobics classes in gyms and clubs. Thus, this study aimed to conduct a systematic review and meta-analysis to assess the effects of vertical position aquatic exercises on the acute BP responses after exercise in older adults.

This systematic review with meta-analysis was conducted in adherence to the PRISMA guidelines¹⁸. Protocol details can be accessed on the platforms Protocol.io (available at: dx.doi.org/10.17504/protocols.io.bp2l69k3rlqe/v1) and PROSPERO (CRD42022375929).

Search Strategy

The searches were conducted in the following digital databases: EMBASE, PUBMED, Lilacs, SPORTDiscus, and Web of Science, up to August 18, 2023. The search was divided into three categories of terms: Exercise, Post-exercise hypotension, and Elderly. Within each category, terms were separated by union operators (i.e., "OR"), and the categories were separated by parentheses and intersection operators (i.e., "AND"). The complete search was performed only in the title and abstract using the following combination of terms in the chosen databases:

(“Water exercise” OR “Water exercises” OR “Exercises in water” OR “Aquatic Exercise” OR “Aquatic Exercises” OR “Water-based exercise” OR “Water-based exercises” OR “Water-based activities” OR “Water aerobics” OR “Water aerobic exercise” OR “Water aerobic exercises” OR “Deep water” OR “Water running” OR “Running in water” OR “Water walking” OR Aquajogging OR “Shallow water walking” OR “Aquatic environment” OR “Water resistance” OR “Exercises in a pool” OR “Pool exercise” OR “Water plyometric” OR Swimming) AND (“Post-exercise hypotension” OR “Post exercise hypotension” OR Hypotension OR “Blood pressure” OR Systolic OR Diastolic OR “Lowering blood pressure” OR “Acute blood pressure” OR “Mean blood pressure”) AND (Aged OR “Older adults” OR Elderly OR Older OR “Middle age”).

Eligibility criteria

The following categories of studies were eligible: 1) Population: Human, both sexes, age (≥ 60 years); 2) Intervention: Acute session of any form of aquatic exercise in a vertical position; 3) Control: Immersion in water without exercise or rest on land; 4) Outcome: BP values after aquatic exercise (SBP, DBP, or mean arterial pressure - MAP); 5) Languages: English, Portuguese, and Spanish; 6) Study designs: Randomized clinical trials, non-randomized trials, and cross-sectional studies; 7) Publication dates: No time limit.

Screening and data extraction process

During the screening, eligibility, inclusion, and data extraction phases, two reviewers (C. P. G. and T. M. S.) independently assessed the studies in duplicate. After reviewing the reviewers' responses, discrepancies were resolved through consensus or by a third reviewer when necessary. The studies were organized by the reference manager, Rayyan (https://www.rayyan.ai/), and recorded in a spreadsheet for data extraction and organization. For studies that presented data only in graphs or figures without numerical representation, the WebPlotDigitizer software (https://automeris.io/WebPlotDigitizer/) was used to obtain numerical values, and those that presented BP values in standard error were transformed into standard deviation. Additionally, there was communication with the authors of the studies when necessary; information could not be obtained from the full text of the included articles.

Data extraction for each study included: 1) General description (identification code, author, publication year, language, and study design); 2) Participant details (gender, sample size, and age); 3) Exercise description (modality, intensity, and volume); 4) Control description (body position on land or in water); 5) Pool characteristics (water temperature); 6) Values related to the primary outcome of the study (SBP and DBP values).

Risk of bias and quality of evidence (GRADE)

The risk of bias analysis was conducted using the Joanna Briggs Institute (JBI) tools^19,20. The Critical Appraisal tools for Randomized Controlled Trials and Quasi-Experimental Studies were employed, and the assessments were duplicated by two independent reviewers (C. P. G. and T. M. S.). The quality of evidence for each outcome was classified using the GRADEpro GDT software®²¹, developed by the Classification of Recommendations, Assessment, Development and Evaluation Working Group (GRADE). The GRADE approach assesses the quality of a body of evidence (QoE) defined as confidence in estimates of effects of alternative management strategies and outcome is categorized as ⊕⊕⊕⊕ (high), ⊕⊕⊕○ (moderate), ⊕⊕○○ (low), or ⊕○○○ (very low). The results of these assessments are presented in the results section in both textual and graphical formats.

Data synthesis and quantitative approaches

Data analysis was conducted using the programming language R²² through the "meta" and "metafor" packages²³. The data were analyzed based on mean differences (MD) and standardized mean differences (SMD). The effect size²⁴ given by SMD is considered small = 0.2 to 0.49, medium = 0.5 to 0.79, and large = > 0.8. Kendall's tau and I² were used as measures of heterogeneity. Pooled effects were presented through forest plots of BP responses up to 1 hour and 24 hours after sessions.

The protocol anticipated a subgroup analysis, in which we divided the studies into those that analyzed BP after high-intensity interval exercises (HIIE) and those that analyzed after moderate-intensity continuous exercises (MICE) versus a control session. Sensitivity analysis was performed by searching for outliers using the "externally standardized residuals" method (standardized residuals values greater than 1.96 on the standardized residuals plot) and searching for influential points using the methods of "difference in fits" (DFFITS, identifying values above 1 or below − 1), "Covariance Ratio" (identifying values below 1), and "Cook's Distance" (identifying values much distant from the others). Publication bias analyses were conducted through a funnel plot with the Trim and Fill method and asymmetry hypothesis tests (Egger's test).

Study identification

Initially, 1156 studies were identified in the databases, and 253 were excluded as duplicates. After exclusions, the screening phase occurred, where the titles and abstracts of 903 studies were read, and those meeting the inclusion criteria were selected. Subsequently, 31 studies were identified for possible inclusion in the present review, but four studies could not be found in the databases. Researchers attempted to contact the authors of these studies via email and other social media platforms but were unsuccessful. In the end, 27 studies were read in full text, and only eight were included for qualitative analysis, with seven included for quantitative analysis (Fig. 1).

Qualitative analysis

Eight studies were included, all conducted in Brazil (Table 1). A total of 197 individuals participated in the studies, of which 152 were women, 15 were men, and 30 were of undefined sex. The average age of the participants was 67.6 ± 1.7 years. Seven studies involved medicated hypertensive older people, while another study¹⁶ did not specify whether the sample had this condition, with an average resting BP of 128/75 mmHg. Regarding the modalities of aquatic exercises, five studies^{13,14,16,25,26} implemented water aerobics interventions (comprehensive exercises for upper and lower limbs), one study²⁷ performed HIIE (1 minute of running and 2 minutes of walking) and one session of walking. Finally, one study included an HIIE session (jumping exercises)²⁸ and another a walking session²⁹.

All studies included a control session. However, only two studies^27,28 had an immersed control session, and two others^26,29 did not describe the control method. The intervention and control sessions occurred in the same pool, with a temperature between 28 to 32 ºC. In four studies^13,16,27,29 the intensity of the exercise was estimated using the perceived exertion index (RPE) according to the Borg Scale. The RPE ranged from 4 to 5 on Borg’s 0 to 10 scale and 9 to 17 on Borg’s 6 to 20 scale. Three studies^14,25,26 estimated intensity through exercise maximum heart rate (70 to 75%), and another²⁸used reserve heart rate (60 to 89%).

Regarding BP measurements, seven studies^{13,14,16,26–29} used an automatic monitor from 10 minutes to 1 hour post-session, and three studies^25,27,29 performed ambulatory 24-hour post-exercise blood pressure monitoring (ABPM):

Up to 1 hour after sessions

Cunha et al. (2012) found a significant reduction in SBP and DBP 30 minutes after exercise compared to intragroup resting values. In 2017, the same authors observed a reduction in BP after 30 minutes compared to immediately after exercise¹⁴; however, SBP and DBP levels returned to normal resting values after exercise. In 2021, the same authors found a significant reduction in SBP by up to 4.6 mmHg 30 minutes after exercise compared to the control session²⁶.

Júnior et al. (2018) found reductions in SBP and DBP at 15, 30, 45, and 60 minutes after exercise compared to rest and the control session. At 45 minutes, SBP decreased by 18 mmHg, and DBP decreased by 4 mmHg compared to pre-aquatic exercise values. Machado et al. (2020) also found significant reductions in BP 30 minutes after exercise compared to the control session.

Over 24 hours after the sessions

Cunha et al. (2018) conducted the same intervention as in 2017, evaluating BP over 24 hours, and found a significant reduction in SBP and DBP up to 12 hours post-exercise compared to the control session.

Marçal et al. (2022) found that the HIIE session led to a more significant reduction in SBP after 45 minutes compared to the first post-session measurement than the walking session. Additionally, both sessions did not induce changes in BP over 24 hours. However, Ngomane et al. (2019) found that walking resulted in a reduction in daytime and nighttime SBP and daytime DBP compared to the control session (-4.5 to -9.5 mmHg) and daytime DBP (-4.1 to -6.5 mmHg) compared to exercise.

Quantitative Analysis

The study by Machado et al. (2020) was not included in the meta-analysis because it was the only study that presented BP results in delta and did not provide raw values. Therefore, the study exhibits high heterogeneity compared to the other included studies.

Up to 1 hour after the sessions

The meta-analytic results for SBP and DBP are presented in Fig. 2. Aquatic exercise showed a favorable effect on SBP response (SMD = -0.58 [-0.89; -0.27], i²= 33%), representing an average reduction of -6.86 mmHg [-10.72; -3.00], i² = 50% (Fig. 2a). It showed a null effect for DBP (SMD = -0.20 [-0.52; 0.11], i²= 36%), with an average reduction of -1.91 mmHg [-4.70; 0.87], i² = 49% (Fig. 2b). Sensitivity analyses did not identify potential outliers.

The analysis of funnel plots indicates a potential publication bias, as the trim and fill analyses suggested two missing studies for SBP (Fig. 3a) and three studies for DBP (Fig. 3b). However, the asymmetry test does not indicate a potential publication bias for SBP (Egger's Test: p-value = 0.10) but does for DBP (Egger's Test: p-value = 0.01).

Over 24 hours after the sessions

The meta-analytic results for SBP and DBP are presented in Fig. 4. Aquatic exercise showed a favorable effect on SBP response (SMD = -0.41 [-0.79; -0.02], i²= 0%), reducing by -4.14 mmHg [-7.75; -0.53], i² = 0%. It also showed a null effect for DBP (SMD = -0.21 [-0.59; 0.17], i²= 0%), with an average reduction of -1.29 mmHg [-3.57; 0.98], i² = 0%. Sensitivity analyses did not identify potential outliers.

Funnel plot analysis indicated no missing studies for SBP (Fig. 5a) or DBP (Fig. 5b). The asymmetry tests do not indicate a potential publication bias for SBP (Egger's Test: p-value = 0.97) and DBP (Egger's Test: p-value = 0.78).

Subgroup analysis

Up to 1 hour after the sessions

Only two studies^27,28 conducted HIIE, and five conducted MICE^{13,14,26,27,29} (Fig. 6).

HIIE

Showed a favorable effect on SBP (Fig. 6a) response up to 1 hour after exercise, representing a mean reduction of -15.50 mmHg [-24.40; -6.61], i² = 52%, (SMD = -0.87 [-1.54; -0.20], i²= 61%). Regarding DBP (Fig. 6b), HIIE led to a reduction of -5.97 mmHg [-11.51; -0.43], i2 = 64%, (SMD = -0.63 [-1.28; -0.02], i²= 61%).

MICE

Showed a favorable effect on SBP (Fig. 6a) response up to 1 hour after exercise, representing a mean reduction of -4.91 mmHg [-7.75; -2.07], i² = 16%, (SMD = -0.47 [-0.79; -0.16], i²= 22%). It also showed a null effect for DBP (Fig. 6b), representing a mean reduction of -0.18 mmHg [-2.51; 2.14], i² = 8% (SMD = -0.06 [-0.36; 0.25], i²= 0%).

Over 24 hours after the sessions

Only one study²⁷ evaluated BP during 24 hours after HIIE. For this reason, it was not possible to perform subgroup analysis.

Bias Analysis and quality of evidence (GRADE)

Overall, the clinical trials showed a low risk of bias in the assessed domains (see Supplementary Table S1 online). Regarding randomized clinical trials, all used either online randomization or an envelope method (question 1). However, Marçal et al. (2022) was the only study that did not describe the procedure for allocation concealment (question 2) of the draw (e.g., whether the envelope was numbered and sealed), presenting a potential bias related to selection and allocation. None of the interventions apply treatment and assessor blinding (questions 4 and 5). Additionally, the sessions occurred identically to the intervention of interest (question 6), indicating no bias related to intervention administration.

No study provided information about outcome assessors (question 7). However, all studies' results were measured the same way between intervention and control sessions (question 8), and the measures used for BP assessment were validated protocols and devices (question 9). Therefore, the studies show low bias in outcome assessment, detection, and measurement.

Regarding bias related to participant retention (question 10), only the study by Júnior et al. (2018) did not describe sample loss throughout the study. Participants were analyzed about group randomization (question 11), and only Cunha et al. (2021) did not explain all the tests performed in the statistical analysis, in addition to lacking a sample size calculation (question 12). Finally, all studies presented a well-conducted standard randomized clinical trial design (question 13), in which only the study by Cunha et al. (2021) was not a crossover trial; however, all individuals had the same baseline characteristics.

Regarding non-randomized clinical trials (see Supplementary Table S2 online), both clearly defined "cause" and "effect" (question 1). Machado et al. (2020) did not present the baseline characteristics of participants in each comparison session, indicating a possible selection bias (question 2) since it is not a crossover trial. In both studies, participants were not exposed to another intervention simultaneously with the intervention of interest (question 3), with only the exercise and control sessions (question 4). Furthermore, outcome measures were taken multiple times before and after the session (question 5). Cunha et al. (2012) were confusing regarding follow-up, as it did not indicate if there was sample loss during the sessions, and Machado et al. (2020) did not provide sample size and loss information for each session (question 6).

All BP results were measured in the same way in both sessions and studies (question 7) and using equipment validated in the literature (question 8). Finally, the study by Cunha et al. (2012) performed an incorrect statistical test for analyzing BP at different time points, and Machado et al. (2020) did not provide an adequate description of the statistical analysis, weakening the validity of the results (question 9).

The quality analysis performed by the GRADE software indicated high certainty of evidence (⨁⨁⨁⨁) for all outcomes assessed, including SBP and DBP during 1 hour and 24 hours after the aquatic exercise session (see Supplementary Table S3 online).

This systematic review and meta-analysis aimed to assess the effects of vertical position aquatic exercises on acute BP responses in older adults. The results showed that aquatic exercise reduced SBP by -6.86 mmHg up to 1 hour and by -4.14 mmHg 24 hours after the session. However, it showed a null effect on DBP responses. Additionally, subgroup analysis showed that HIIE reduced SBP by -15.50 mmHg and DBP by − 5.97 mmHg after sessions. On the other hand, continuous moderate-intensity exercise reduced SBP by -4.91 mmHg, with no effect on DBP up to 1 hour after sessions.

A recent meta-analysis¹⁷, which was conducted with hypertensive individuals, compared the hypotensive effects of an aquatic exercise session with a control session and found similar results. The study indicated that exercise in the aquatic environment reduced SBP by -6,0 mmHg and DBP by -1,9 mmHg but without significant effects over 24 hours¹⁷. Acute BP responses are of great clinical relevance as they provide essential data on chronic BP adaptations in addition to reducing acute cardiovascular risk⁸.

These acute effects can lead to a series of physiological adaptations in BP³⁰. Indeed, the literature includes two meta-analyses demonstrating the long-term benefits of aquatic interventions on BP in adults and older adults^10,31. The SBP significantly decreased by -8,4 mmHg³¹ and − 10,58 mmHg¹⁰, while DBP also showed reductions of -3,3 mmHg³¹ and − 4,40 mmHg¹⁰.

Several factors influence the magnitude of post-exercise hypotension, and these should be considered when interpreting the results. The literature indicates that predictors modulating the BP response after exercise include baseline BP, age, and physical fitness³². Moreover, in the comparison between normotensive and hypertensive individuals, those with elevated BP exhibit a more pronounced response in PEH³³. Among the studies included in this meta-analysis, three involved physically active older adults^13,14,25, three included sedentary older persons^26,27,29, and one did not specify the level of physical activity²⁸. Indeed, Iellamo et al. (2021) suggested that, in hypertensive older adults, the training status associated with the type of exercise may induce different responses in PEH.

Another factor that should be observed is the environment in which the exercise is being performed, as physiological responses in aquatic and terrestrial environments are distinct in response to the same intensity and volume stimuli³⁴. In this regard, when comparing the effects of exercise on PEH in different environments (aquatic versus terrestrial), Ngomane et al. (2019) found that SBP was reduced below resting levels 45 minutes after an aerobic training protocol performed in the water but not after a similar protocol in the terrestrial environment. Additionally, it is crucial to note that only two studies^27,28 implemented the control session immersed under the same conditions as the exercise session. Consequently, the BP results related to aquatic exercise are more reliable due to the physiological changes occurring during immersion.

According to the review by Alberton and Kruel (2009), several factors influence physiological responses in immersion. These factors include water temperature, body position, immersion depth, initial heart rate, and reduction of hydrostatic weight. Most studies^13,26–29 conducted the sessions with water temperature between 28 and 32°C, while the remaining studies^14,16,25 did not provide this information. Furthermore, only the studies by Júnior et al. (2018) and Marçal et al. (2022) indicated the immersion depth (xiphoid process). Therefore, such methodological differences may interfere with BP responses and compromise the quality of the studies.

Exercise intensity is also an important variable that influences BP reduction. In this regard, only two studies^27,28 conducted HIIE, and six conducted MICE^{13,14,25–27,29}. When analyzing BP responses in HIIE and MICE subgroups, both showed a favorable effect on SBP response up to 1 hour after exercise, representing a mean reduction of -15.50 mmHg and − 4.91 mmHg, respectively. Regarding DBP, HIIE reduced − 5.97 mmHg after exercise, and MICE had no effect. Furthermore, only one study²⁷ evaluated the BP responses of older people 24 hours after the HIIE session. This result shows the gap in the literature on the effects of aquatic HIIE on BP.

Although HIIE promotes an essential reduction in both SBP and DBP after exercise, MICE present more robust and reliable results due to the more significant number of studies in the literature. Two meta-analyses^36,37 assessed BP responses in hypertensive and normotensive individuals after a terrestrial HIIE vs. MICE session. Marçal et al. (2021) found that the effects on BP up to 1 hour after the session were similar between the sessions, while Perrier-Melo et al. (2020) reported that HIIE induced greater post-exercise hypotension (SBP − 3 mmHg; SBP − 1.3 mmHg). Furthermore, HIIE reduced BP (-5.3 mmHg) more than MICE (-1.63 mmHg) during daytime ambulatory monitoring³⁶. Despite the significant findings, few studies were included in both meta-analyses.

Evidence suggests that the mechanisms by which aquatic exercises reduce BP and exert their hypotensive effects are due to the reduction of peripheral vascular resistance¹², suppression of the renin-angiotensin system, and activation of cardiopulmonary and baroreflex mechanisms^38,39, leading to alterations in renal functions⁴⁰. These changes occur due to hydrostatic pressure, redirecting approximately 700 mL of blood flow from the extremities (increasing venous return) to the chest^41,42.

Considering the higher prevalence of cardiovascular risks in the older adult population, the effects of immersion associated with physical exercise can help reduce adverse effects. Additionally, most studies were conducted with older adults hypertensive women^{13,14,25,26,28}. It is known that post-menopause is marked by various hormonal and functional changes, leading to a higher risk of cardiovascular diseases such as arterial hypertension⁴³. Therefore, PEH is of great relevance for older people in the treatment and prevention of hypertension, and it is crucial to understand the effects of aquatic exercise on the cardiovascular system and the magnitude of acute adaptations in this context.

However, it is important to emphasize some limitations of the present meta-analysis. The training level significantly influences the HPE response, which should be monitored or observed since it may present divergent values for future research comparing sedentary and trained older adults in the aquatic environment. In some studies, the prescription of exercise intensity was based on the heart rate achieved in maximum tests conducted on land, which could overestimate training values in the aquatic environment. Additionally, most studies conducted the control session on land, where the BP response differs from the aquatic environment.

Future studies should explore the effects of aquatic exercise on BP in other hypertensive populations, such as postmenopausal women and men. Additionally, we emphasize the importance of conducting studies with different exercise protocols (e.g., high-intensity interval training), as they may elicit different BP responses. Another suggestion is standardizing the control session under the same conditions as the aquatic intervention, such as immersion in the same pool and body position. Furthermore, few studies presented the effects of BP during the 24 hours after aquatic exercise, which may have influenced the meta-analysis results. Finally, we highlight the importance of this study as the first meta-analysis on post-aquatic exercise hypotension in older adults, given the clinical significance of reducing BP for this population.

This systematic review and meta-analysis provide evidence that aquatic exercise in an upright position reduces SBP for up to 1 hour and 24 hours without a significant effect on the DBP of older persons. Furthermore, subgroup analysis showed that HIIE and MICE reduced SBP, and only HIIE reduced DBP by 1 hour after the sessions. This study provides relevant results that help clarify the literature on the importance of aquatic exercise in acutely reducing BP in older people.

Acknowledgements

We would like to thank the Brazilian government for financing the T.M.S scholarship through the “Personnel Improvement Coordination Higher Education – CAPES”. This work supervised by Dr. Kanitz and Dr. Puga.

Author contributions

T.M.S had the idea for the article. I.M.M, C.P.G, A.C.K and G.M.P participated in the planning and structuring of the study. T.M.S, I.M.M, C.P.G, C.M and J.C.Z carried out the literature search and data analysis. T.M.S, I.M.M, C.P.G, C.M, J.C.Z, A.C.K and G.M.P wrote and critically revised the work. All authors approved the final version of the manuscript.

This work was also supervised by Dr. Kanitz and Dr. Puga.

Competing interests

The authors declare no competing interests.

Additional Information

Correspondence and requests for materials should be addressed to G.M.P.

Data availability statement

The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.

Netto, M. P. O estudo da velhice no século XX: histórico, definição de campo e termos básicos. in Tratado de Geriatria e Gerontologia 62–75 (Editora Guanabara Koogan Ltda, 2011).
World Health Organization. Hypertension. Fact sheets https://www.who.int/news-room/fact-sheets/detail/hypertension (2023).
Barroso, W. K. S. et al. Brazilian guidelines of hypertension – 2020. Arquivos Brasileiros de Cardiologia 116, 516–658 (2021).
Mancia, G. et al. 2023 ESH Guidelines for the management of arterial hypertension The Task Force for the management of arterial hypertension of the European Society of Hypertension: Endorsed by the International Society of Hypertension (ISH) and the European Renal Association (ERA). Journal of Hypertension 41, 1874–2071 (2023).
Gibbs, B. B. et al. Physical activity as a critical component of first-line treatment for elevated blood pressure or cholesterol: Who, what, and how?: A scientific statement from the American Heart Association. Hypertension 78, e26–e37 (2021).
Liu, S., Goodman, J., Nolan, R., Lacombe, S. & Thomas, S. G. Blood pressure responses to acute and chronic exercise are related in prehypertension. Medicine & Science in Sports & Exercise 44, 1644–1652 (2012).
Iellamo, F. et al. Prolonged post-exercise hypotension: effects of different exercise modalities and training statuses in elderly patients with hypertension. IJERPH 18, 1–11 (2021).
Kenney, M. J. & Seals, D. R. Postexercise hypotension. Key features, mechanisms, and clinical significance. Hypertension 22, 653–664 (1993).
Brito, L. C. et al. Postexercise hypotension as a clinical tool: a “single brick” in the wall. Journal of the American Society of Hypertension 12, e59–e64 (2018).
Reichert, T. et al. Aquatic training in upright position as an alternative to improve blood pressure in adults and elderly: a systematic review and meta-analysis. Sports Med 48, 1727–1737 (2018).
Alberton, C. et al. Vertical ground reaction force during water exercises performed at different intensities. Int J Sports Med 34, 881–887 (2013).
Pendergast, D. R., Moon, R. E., Krasney, J. J., Held, H. E. & Zamparo, P. Human physiology in an aquatic environment. in Comprehensive Physiology (ed. Terjung, R.) 1705–1750 (Wiley, 2015). doi:10.1002/cphy.c140018.
Cunha, R. M. et al. Subacute blood pressure response in elderly hypertensive women after a water exercise session: a controlled clinical trial. High Blood Press Cardiovasc Prev 19, 223–227 (2012).
Cunha, R. M. et al. Acute blood pressure response in hypertensive elderly women immediately after water aerobics exercise: A crossover study. Clinical and Experimental Hypertension 39, 17–22 (2017).
Júnior, F. et al. The effects of aquatic and land exercise on resting blood pressure and post-exercise hypotension response in elderly hypertensives. CVJA 31, 8–14 (2020).
Machado, O. A. S., Campos, S. V. P., Killian, L. F., Machado, G. A. C. & Gianolla, F. Effect of a single exercise session on blood glucose and blood pressure in elderly. JPES 20, 2637–2642 (2020).
Trindade, C. O., Oliveira, E. C., Coelho, D. B., Casonatto, J. & Becker, L. K. Effects of aquatic exercise in post-exercise hypotension: a systematic review and meta-analysis. Front. Physiol. 13, 1–12 (2022).
Page, M. J. et al. A declaração PRISMA 2020: diretriz atualizada para relatar revisões sistemáticas. Revista Panamericana de Salud Pública 46, 1–12 (2022).
Barker, T. H. et al. The revised JBI critical appraisal tool for the assessment of risk of bias for randomized controlled trials. JBI Evidence Synthesis 21, 494–506 (2023).
Lockwood, C. et al. Systematic reviews of qualitative evidence. in JBI Manual for Evidence Synthesis (JBI, 2024). doi:10.46658/JBIMES-20-04.
Schunemann HJ, et al. The development methods of official GRADE articles and requirements for claiming the use of GRADE - a statement by the GRADE Guidance Group. J Clin Epidemiol. 19,159:79–84 (2023). doi: 10.1016/j.jclinepi.2023.05.010.
Vienna R Foundation for Statistical Computing. R: a language and environment for statistical computing. https://www.r-project.org (2019).
Viechtbauer, W. Conducting meta-analyses in R with the metafor package. J. Stat. Soft. 36, 1–48 (2010).
Cohen, J. Statistical Power Analysis for the Behavioral Sciences. (Psychology Press, New York, NY, 2009).
Cunha, R. M. et al. Postexercise hypotension after aquatic exercise in older women with hypertension: a randomized crossover clinical trial. American Journal of Hypertension 31, 247–252 (2018).
Cunha, R. M., Arsa, G., Oliveira-Silva, I., Rocha, I. F. & Lehnen, A. M. Acute blood pressure effects in older adults with hypertension after different modalities of exercise: an experimental study. Journal of Aging and Physical Activity 29, 952–958 (2021).
Marçal, I. R. et al. Acute high-intensity interval exercise versus moderate-intensity continuous exercise in heated water-based on hemodynamic, cardiac autonomic, and vascular responses in older individuals with hypertension. Clinical and Experimental Hypertension 44, 427–435 (2022).
Júnior, E. A. S. et al. High-intensity interval aquatic exercise session promotes post-exercise hypotension in hypertensive elderly: a randomized controlled trial. Journal of Exercise Physiology online 21, 149–161 (2018).
Ngomane, A., Fernandes, B., Guimarães, G. & Ciolac, E. Hypotensive effect of heated water-based exercise in older individuals with hypertension. Int J Sports Med 40, 283–291 (2019).
Wegmann, M. et al. Postexercise hypotension as a predictor for long-term training-induced blood pressure reduction: a large-scale randomized controlled trial. Clinical Journal of Sport Medicine 28, 509–515 (2018).
Igarashi, Y. & Nogami, Y. The effect of regular aquatic exercise on blood pressure: A meta-analysis of randomized controlled trials. Eur J Prev Cardiolog 25, 190–199 (2018).
Pescatello, L. S. et al. Exercise and hypertension. Medicine & Science in Sports & Exercise 36, 533–553 (2004).
Cardoso, C. G. et al. Acute and chronic effects of aerobic and resistance exercise on ambulatory blood pressure. Clinics 65, 317–325 (2010).
Kruel, L. F. M. et al. Cardiorespiratory responses to stationary running in water and on land. J Sports Sci Med 12, 594–600 (2013).
Alberton, C. L. & Kruel, L. F. M. Influence of immersion on resting cardiorespiratory responses. Rev Bras Med Esporte 15, 228–232 (2009).
Marçal, I. R. et al. Post-exercise hypotension following a single bout of high intensity interval exercise vs. a single bout of moderate intensity continuous exercise in adults with or without hypertension: a systematic review and meta-analysis of randomized clinical trials. Front. Physiol. 12, 1–13 (2021).
Perrier-Melo, R. J., Costa, E. C., Farah, B. Q. & Costa, M. D. C. Acute effect of interval vs. continuous exercise on blood pressure: systematic review and meta-analysis. Arquivos Brasileiros de Cardiologia 115, 5–14 (2020).
Gabrielsen, A. et al. Immediate baroreflex-neuroendocrine interactions in humans during graded water immersion. J Gravit Physiol 3, 22–23 (1996).
Reilly, T., Dowzer, C. N. & Cable, N. The physiology of deep-water running. Journal of Sports Sciences 21, 959–972 (2003).
Larochelle, P., Cusson, J. R., Du Souich, P., Hamet, P. & Schiffrin, E. L. Renal effects of immersion in essential hypertension. American Journal of Hypertension 7, 120–128 (1994).
Park, K. S., Choi, J. K. & Park, Y. S. Cardiovascular regulation during water immersion. Appl Human Sci 18, 233–241 (1999).
Chu, K. S., Rhodes, E. C., Taunton, J. E. & Martin, A. D. Maximal physiological responses to deep-water and treadmill running in young and older women. Journal of Aging and Physical Activity 10, 306–313 (2002).
Abbas, Sz., Sangawan, V., Das, A. & Pandey, A. Assessment of cardiovascular risk in natural and surgical menopause. Indian J Endocr Metab 22, 223–228 (2018).

Table 1 is available in the Supplementary Files section.

No competing interests reported.

Download PDF

Reviews received at journal
15 Aug, 2024
Reviewers agreed at journal
31 Jul, 2024
Reviewers invited by journal
31 Jul, 2024
Editor assigned by journal
22 Jul, 2024
Editor invited by journal
23 May, 2024
Submission checks completed at journal
23 May, 2024
First submitted to journal
03 May, 2024

You are reading this latest preprint version

Effects of post-aquatic exercise hypotension in older adults: a systematic review with meta-analysis

Status:

Version 1

Abstract

Figures

Introduction

Methods

Search Strategy

Eligibility criteria

Screening and data extraction process

Risk of bias and quality of evidence (GRADE)

Data synthesis and quantitative approaches

Results

Study identification

Qualitative analysis

Quantitative Analysis

Subgroup analysis

Bias Analysis and quality of evidence (GRADE)

Discussion

Declarations

References

Table 1

Additional Declarations

Supplementary Files

Status:

Version 1