An interventional study of Aquatic aerobic exercise program and Cognitive tasks in Aging, sponsored by Federal University of Pelotas. Recruiting at 1 site in Brazil. Open to female participants aged 60 Years to 75 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-09.
Sponsored by Federal University of Pelotas · Not applicable, Interventional, and Treatment
The aquatic environment has characteristics that favor the adherence of older adults to exercise programs, and studies have shown that programs in this setting are effective in enhancing various aspects of physical fitness as well as cognitive function in this population. Research has explored whether incorporating cognitive tasks into an aquatic exercise program could offer additional benefits, but it remains uncertain whether this approach leads to greater improvements in cognitive function compared to aquatic exercises alone. The present protocol reports the WaterCog Study, which aims to evaluate the effects of an aquatic aerobic exercise program combined with cognitive tasks, compared to a conventional aquatic aerobic exercise program and a control group, on cognitive function and other health-related outcomes in older adults. This trial is a randomized, single-blinded, three-arm, parallel, superiority trial. A total of 98 older adults are randomized into one of three groups: 1) an aquatic aerobic exercise program combined with cognitive tasks, 2) a conventional aquatic aerobic exercise program, and 3) a control group. Participants in both exercise groups complete a 12-week exercise program with two weekly sessions on non-consecutive days. The primary outcome is cognitive function, while secondary outcomes include physical function, cardiovascular, and psychosocial parameters. Outcomes are measured at baseline, post-intervention, and at the 12-week follow-up after the end of the intervention period. The analysis plan will employ an intention-to-treat approach and per-protocol criteria. The conceptual hypothesis of the study is that both training programs will significantly improve the investigated outcomes compared to the control group. Additionally, it is expected that aquatic exercises with cognitive tasks will promote additional benefits in cognitive function, with similar gains in physical function, cardiovascular, and psychosocial parameters compared to conventional aquatic aerobic exercises in post-intervention and follow-up measures.
9,798 studies on the registry are indexed under Motor Activity; 1,910 are open to participants now.
This study's planned enrollment of 98 is above the median of 60 across 8,388 interventional studies indexed under Motor Activity.
Browse Motor Activity studies →Federal University of Pelotas is the lead sponsor of 52 studies on the registry; 4 are open to participants now.
Compared within Motor Activity, the registry's first condition term, which may not be this study's main condition. Counted across the registry records on this site, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Other: Aquatic aerobic exercise program · Other: Cognitive tasks
Other: Aquatic aerobic exercise program
The aquatic exercise sessions include the following exercises: butt kick, frontal kick, cross-country skiing, and stationary running. These exercises are commonly used in water aerobics classes and provide controlled osteoarticular impact, being safe for older women (Alberton et al., 2019). Training intensity is prescribed using Borg's 6-20 rating of perceived exertion (RPE) scale. The adopted strategy is based on interval training, which alternates between high-intensity effort and low-intensity active recovery phases. Each block consists of 4 minutes of effort (RPE 13 - 15), with one minute for each exercise (butt kick, frontal kick, cross-country skiing, and stationary running) followed by 1 minute of active recovery (RPE 11), performed with stationary running. To facilitate monitoring, an RPE scale (measuring 0.90 × 1.20 m) is fixed to the outside of the pool, in front of the participants.
This group performs the same aerobic training protocol used by the conventional aquatic program group. Additionally, cognitive tasks are performed during the active recovery phases. Cognitive training encompasses different domains of cognition in all sessions, including semantic fluency, processing speed, cognitive flexibility, inhibitory control, memory, attention, and reasoning. The exercises vary in each class, with progression in complexity in each mesocycle.
Objective cognitive function - Digit Span Test
The Digit Span Test is used to assess working memory and attention span (Schroeder et al., 2012). The Digit Span Test requires participants to verbally recall a sequence of numbers dictated by the examiner. The test begins with three numbers ranging from 0 to 9, read at 1-second intervals, which participants must remember in the correct order. The sequence increases by one digit if pronounced correctly. If participants fail to recall the correct sequence twice in a row, the test ends. The number of digits correctly recalled is recorded as the test result, with a higher score indicating better performance.
Time frame: Baseline (week 0), post-intervention (week 13), and 12-week follow-up (week 25)
Objective cognitive function - Controlled Oral Word Association Test
The Controlled Oral Word Association Test (COWAT) is used to assess verbal fluency, working memory, and inhibitory control (Ross et al., 2007). In this test, participants must say as many words as possible that start with the letters "F," "A," and "S" within 1 minute for each letter. Proper names, repeated words, and variations in gender, number, and conjugation are not considered. A higher number of words in each test indicates better verbal fluency.
Time frame: Baseline (week 0), post-intervention (week 13), and 12-week follow-up (week 25)
Objective cognitive function - Trail Making Test (TMT)
The validated version of the Trail Making Test (TMT) for the Brazilian population is used to assess aspects of objective cognitive function (Carvalho \& Caramelli, 2020). In the first part of the instrument (TMT-A), which measures visual attention and processing speed, participants must draw a line connecting the numbers 1 to 25 in ascending order. In the second part (TMT-B), which measures cognitive flexibility and executive function, participants connect numbers (1-13) and letters (A-L) in an interleaved numerical and alphabetical order. Participants are instructed to maintain pencil-and-paper contact throughout the test, and shorter completion times indicate better performance.
Time frame: Baseline (week 0), post-intervention (week 13), and 12-week follow-up (week 25)
Self-perception of cognitive function
The Brazilian version of the Cognitive Failures Questionnaire (CFQ) is used to measure the frequency of cognitive failures in everyday life, such as lapses in attention, memory problems, and failures in executing intentional actions (Paula et al., 2017). The questionnaire consists of 25 self-administered items, with responses on a Likert-type scale from 0 to 4, which assess the frequency of cognitive failures in different everyday contexts. The total score ranges from 0 to 100 points, with higher scores indicating a greater perceived frequency of cognitive failures and, therefore, poorer self-perception of cognitive function.
Time frame: Baseline (week 0), post-intervention (week 13), and 12-week follow-up (week 25)
Aerobic fitness
The 6-minute Walk Test (6MWT) is performed to measure aerobic fitness. The course proposed in the original test is 45.72 m rectangular. The course will be adapted for a straight line of 30 m in length, demarcated with cones every 3 m. Participants are instructed to walk for 6 minutes in a flat 30m course, where the total distance walked "as fast as possible" is assessed
Time frame: Baseline (week 0) to post-training (week 13)
Lower limb strength
The 30-s Chair-Stand test is performed to measure the strength of the lower limbs. Participants are instructed to sit and stand up from a chair 43 cm high from the seat, without the aid of the upper limbs, as many times as possible for 30 s. The total number of complete repetitions performed within the 30 seconds is recorded as the result, with higher values indicating greater lower body strength.
Time frame: Baseline (week 0) to post-training (week 13)
Upper limb strength
The Arm Curl test is performed to measure the strength of the upper limbs. Starting at full elbow extension and holding a 2 kg dumbbell in each hand, participants are instructed to perform the maximal number of elbow crunches over the full range of motion for 30 s. The test is performed with both upper limbs. The total number of complete repetitions performed within the 30 s is recorded as the result, with higher values indicating greater upper body strength.
Time frame: Baseline (week 0) to post-training (week 13)
Lower limb flexibility
The Sit-and-Reach test is performed using a Wells Bench to assess lower limb flexibility, particularly of the hamstring and lower back muscles. Participants sit barefoot on the floor with their legs extended and together, knees fully extended, and the soles of the feet flat against the front of the bench. With arms extended and hands overlapping, they slowly bend forward from the hips, sliding their hands along the measurement scale on the bench, without flexing the knees or using compensatory movements. The maximum reach is held for approximately two seconds, and the greatest distance reached in centimeters in three attempts is recorded.
Time frame: Baseline (week 0) to post-training (week 13)
Agility and dynamic balance
The Timed Up and Go (TUG) test is performed to measure agility and dynamic balance. Participants are instructed to get up from the chair (43 cm), turn around a marker that will be 3m, and return to the starting position. The shortest time of the two attempts is considered the result.
Time frame: Baseline (week 0) to post-training (week 13)
Dual-task performance
Dual-task performance involves simultaneously performing the TUG test and a cognitive task. Participants are instructed to do the TUG while reciting alternating letters (e.g., A, C, E, etc.). The time taken for the TUG and the number of correctly recited letters are recorded as test results.
Time frame: Baseline (week 0) to post-training (week 13)
Blood pressure
Office systolic blood pressure (SBP) and diastolic blood pressure (DBP) measurements are obtained using calibrated and automated oscillometric devices (HEM-7320, OMRON, China). Participants are kept in a calm environment for 5 min, and then measurements are performed in both arms of the participant. Three measurements, with an interval of 1 to 2 min, are taken in the arm with the highest initial value. The average of the three measurements is considered the subject's office blood pressure.
Time frame: Baseline (week 0) to post-training (week 13)
Blood pressure reactivity
Blood pressure reactivity is measured as the difference between values recorded during a mental stressor and those obtained at rest. The Stroop Test (Stroop, 1935) is used to induce mental stress, presented via a video on a screen in front of the participant for three minutes. Every two seconds, a visual stimulus consisting of a word written in a specific color will appear, with the color of the word and its meaning being incongruent (for example, the word "blue" written in red). The participant must respond verbally and as quickly as possible to the color of the letters, ignoring the meaning of the word. Throughout the test, systolic and diastolic blood pressure are measured by the auscultatory method, using a stethoscope and a calibrated aneroid sphygmomanometer, with one reading every minute, for a total of three readings. The reference arm is the same one used for resting BP assessments. After completing the test, participants are asked to rate their perceived stress level using a
Time frame: Baseline (week 0) to post-training (week 13)
Heart rate variability
Heart rate variability (HRV) is measured with participants seated and resting for 10 minutes, during which time their heart rate is continuously recorded using the Polar H10 chest sensor, a validated and widely used device for HRV analysis. Data collection takes place in a quiet environment, with a controlled temperature between 24°C and 26°C. Data is collected via Bluetooth and stored in the Polar Flow app, later exported in a compatible format (.txt or .csv). The final five minutes of the resting period are considered for analysis, as they offer greater physiological stability. Data are processed in Kubios HRV® software, with automatic artifact correction using a low threshold filter. HRV analysis follows the recommendations of the Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology (1996), considering time-domain parameters such as SDNN (Standard Deviation of NN Intervals), which reflects the global variability of autonomi
Time frame: Baseline (week 0) to post-training (week 13)
Depressive and anxiety symptoms
The validated version of the HADS for the Brazilian population is used to assess depressive and anxious symptoms (Botega et al., 1995). It is an instrument composed of 14 items, seven of which form the anxiety subscale and the other seven the depression subscale, allowing the assessment of symptoms in the previous week. Each HADS item has four response options ranging from 0 to 3, reaching a maximum of 21 points in each subscale. Participants are instructed to answer the questions based on the last 7 days. Based on the final score of each subscale, participants are categorized as having symptoms of anxiety or depression as "unlikely" (0 to 7 points), "possible" (8 to 11 points), and "probable" (12 to 21 points). Higher scores indicate more severe symptoms and a worse perceived emotional state.
Time frame: Baseline (week 0) to post-training (week 13)
Sleep quality
The validated version of the Pittsburgh Sleep Quality Index (PSQI) for the Brazilian population is used to assess subjective sleep quality and related disorders (Bertolazi et al., 2011). The questionnaire consists of 19 items, grouped into seven components: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disorders, use of sleeping medications, and daytime dysfunction. Each component is scored from 0 (no difficulty) to 3 (severe difficulty), and the sum of the scores results in an overall score ranging from 0 to 21; scores greater than 5 indicate poor sleep quality.
Time frame: Baseline (week 0) to post-training (week 13)
Self-reported quality of life
Quality of life is assessed using the WHOQOL-BREF questionnaire, developed by the World Health Organization and previously validated in the Brazilian population (Fleck et al., 2000). The WHOQOL-BREF comprises 26 items divided into four domains: physical, psychological, social relationships, and environment. This instrument is self-administered, with a 5-point Likert scale, and produces standardized scores ranging from 0 to 100, with higher values indicating better perceived quality of life.
Time frame: Baseline (week 0) to post-training (week 13)
Cognitive status
The validated version of the Mini-Mental State Examination (MMSE) (Brucki et al., 2003) for the Brazilian population is used to screen for cognitive decline, and in this study, it is also used to stratify randomization. The questionnaire is divided into two sections: the first, with a maximum score of 21, requires vocal responses regarding temporal and spatial orientation, memory, and attention; the second, with a maximum score of 9, assesses the ability to name, follow commands, write, and copy a polygon. The maximum total score is 30 points, and the test is not timed. Participants' cognitive function is classified based on cutoff points adjusted for education, as proposed by Brucki et al. (2003). The score is formed by the sum of the items answered correctly; the higher the score, the better the cognitive function.
Time frame: Baseline (week 0)
Sociodemographic and clinical characteristics
Sociodemographic data, health history, medical conditions, and medication use are collected using a standardized questionnaire before the intervention.
Time frame: Baseline (week 0)
Body mass
Body mass measurements are performed using a digital scale with a stadiometer (Welmy, Santa Bárbara d'Oeste - São Paulo, Brazil). Body mass is measured in kilograms.
Time frame: Baseline (week 0) to post-training (week 13)
Height
Height measurements are performed using a digital scale with a stadiometer (WELMY, Santa Bárbara d'Oeste - São Paulo, Brazil). Height is measured in meters.
Time frame: Baseline (week 0) to post-training (week 13)
Body mass index (BMI)
The calculation of the BMI is performed using the equation: BMI = body mass (kg)/height² (m).
Time frame: Baseline (week 0) to post-training (week 13)
Waist and hip circumferences
Waist and hip circumferences are measured with a measuring tape placed around the navel height and the width of the participants' hips, respectively, to calculate the waist-hip ratio.
Time frame: Baseline (week 0) to post-training (week 13)
Physical activity levels
The self-reported physical activity level is measured at baseline and post-intervention using the Godin-Shephard Leisure-Time Physical Activity Questionnaire. The translated and validated Brazilian version of the Godin-Shepard questionnaire is used (São-João et al., 2013). Participants should report the number of times they perform vigorous, moderate, and light physical activities for more than 15 minutes a week. The weekly frequencies of intense, moderate, and light activities should be multiplied by nine, five, and three, respectively. The total weekly leisure activity is calculated in arbitrary units from the sum of the products of each component, allowing for categorizing the individual as insufficiently active or active.
Time frame: Baseline (week 0) to post-training (week 13)
Eating habits
The Food Frequency Questionnaire (FFQ) is used to monitor eating habits. According to the Brazilian Food Guidelines, foods are divided into two groups: in natura/minimally processed foods and processed or ultra-processed foods. The instrument includes a list of 16 foods, and scores are assigned to each based on how often participants report consuming them. The scores can range from 0 to 32 points, with higher scores indicating healthier eating habits. An overall healthy eating score is also calculated by summing all evaluated foods, ranging from 0 to 64 points, where higher scores reflect better eating habits.
Time frame: Baseline (week 0) to post-training (week 13)
Adherence assessments
Adherence measures are taken into account for attendance and compliance in interventions. Attendance is monitored through the session's frequency recording and expressed as the percent of intervention sessions experienced by a participant, given the total number of scheduled sessions. Compliance is defined as the percentage of intervention sessions performed without protocol deviations.
Time frame: Intervention period (week 1 to week 12)
Monitoring the intensity of training sessions
The intensity participants perceive at the end of the last class of each mesocycle is recorded using the perceived exertion index. The validated Brazilian Portuguese version of Borg's Category-Ratio 10 scale, adapted by Foster et al. (2001), is used. The scale has values from 0 to 10, anchored to intensities of perceived effort, with 0 being equivalent to no effort (rest) and 10 to maximum effort.
Time frame: Intervention period (week 4, week 8, and week 12).
Follow-up questionnaire
Each participant answers 14 questions regarding their perception of the intervention using a 7-point Likert scale, in which "1" means "no total agreement" and "7" means "total agreement". The questionnaire is applied post-intervention to assess the participants' perception of safety, enjoyment, motivation, future outlook, benefits for daily life, influence of intervention partners, exercise-related fatigue, satisfaction, self-confidence in physical performance, supervision preference, changes in lifestyle, including physical activity and dietary habits, and main barriers to group participation.
Time frame: Post-training (week 13)
Plan to share: Yes — Individual participant data can be made available by the Trial Coordinator upon reasonable request.
Start is estimated for Sep 2025; primary completion for Aug 2027, 23 months later.
Of 5,147 non-industry interventional studies with no phase under Motor Activity, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 7 and three quarters within 36. This study's planned 23 months is above that.
Counting every sponsor, half of 5,207 studies reached it within 17 months; a quarter within 7 and three quarters within 36.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Federal University of Pelotas