A Two-Phased Pilot Study Evaluating the Feasibility and Acceptability of the Cognitively Enriched Walking Program “Take a Walk with Your Brain” for Older Adults

Given the aging population, finding solutions to retain optimal cognitive capacity is a research priority. The potential of physical activity to reduce the risk of cognitive decline and to enhance cognitive functioning is established. Combining physical with cognitive activity has been put forward as a potentially even more effective way to promote healthy cognitive aging. Most studies on combined interventions have however been conducted in laboratory settings. This paper reports on a two-phased pilot study evaluating the acceptability and feasibility of a newly developed real-life cognitively enriched walking program for adults aged 65+ years. In Phase I, the feasibility and enjoyability of the cognitive tasks was evaluated by conducting walk-along interviews with older adults (n = 163). In Phase II, the cognitively enriched walking program was piloted in two groups of older adults (n = 19), and the feasibility and acceptability of the program and cognitive tasks was evaluated by means of questionnaires and focus groups. The cognitive tasks (i.e., median scores of ≥3 on a total of 4 (Phase I) and ≥6 on a total of 10 (Phase II) for most of the tasks) and the cognitively enriched walking program (i.e., median scores of ≥7 on a total of 10) were considered feasible and acceptable. Based on the input of the participants, key considerations for a feasible and acceptable program were defined: participants should be sufficiently challenged cognitively and physically, social interaction is an important motivator, cognitive tasks should make use of stimuli reflecting daily life and be conducted in group, the rationale for the tasks should be explained to participants, the frequency of the group sessions should be maximum 2 times a week, and the program should be supervised by a trained coach. These results warrant future research to establish the effectiveness of this program.


Introduction
As a result of declined fertility rates and increased life expectancy, the proportion and actual number of older adults has increased considerably over the past decades, and this increase is projected to continue.In 2021, those aged 65 years or older accounted for 20.8% of the population of the European Union, while this proportion is expected to rise to 31.3% by 2100 [1].Life expectancy is also rising and has increased in Europe from 77.6 years in 2002 to 80.4 years in 2020 [2].However, these additional life years are not necessarily lived in good health.In Europe, healthy life expectancy (i.e., the number of years that a person is expected to continue to live in a healthy condition) was 64.5 years for women and 63.5 years for men in 2020 [3].
Healthy aging, defned by the World Health Organization (WHO) as "the process of developing and maintaining the functional ability that enables wellbeing in older age," is therefore considered a key challenge of this decade.Retaining optimal cognitive capacity (i.e., a person's capacity to perform a range of mental functions such as memory and executive functions) is a critical aspect contributing to healthy aging [4,5].Globally, the number of older adults living with dementia was estimated to be 55 million in 2019 and is anticipated to rise to 139 million by 2050, which underpins the importance of cognitive health today and in the future [6].Tus, investigating ways to retain optimal cognitive health at older age and consequently preserving older adults' quality of life is more important than ever.
Although age-associated nonpathological cognitive decline is inevitable, there is an individual variability in the extent and rate of cognitive decline [7][8][9].Maintaining optimal cognitive health is partly determined by unmodifable factors such as genetics, but research has also identifed several modifable "lifestyle" risk factors, such as engagement in physical activity (PA) and cognitive activity (CA) [10][11][12][13].Tese factors can positively impact cognitive health at older age and are found to decrease the risk to develop dementia [10][11][12].
Several systematic reviews and meta-analyses have pointed towards positive association and efects of both physical activity and exercise for cognitive function.For example, a recent systematic review and meta-analysis of 58 observational studies showed that higher PA levels are associated with a 20% decrease in the risk of dementia (pooled relative risk � 0.80; 95% CI [0.77-0.84])when compared with a reference or inactive group [14].Of all exercise (i.e., a structured form of PA) types, the efects of aerobic exercise and resistance training on cognitive functioning have been studied most extensively and have been found to positively afect cognitive functioning (i.e., executive functioning, memory, and attention) in older adults [15,16].Furthermore, an umbrella review by Erickson et al. [15] has shown a moderate efect of long-term moderate-to-vigorous PA interventions (i.e., more than one session) on cognitive outcomes in adults aged 50 and older (i.e., Hedges' g ranging from nonsignifcant to 0.48).Tere are several potential pathways for the benefcial efect of PA on cognitive function.Physiologically, these efects could be attributed to the PA-induced neuroplasticity, through an increase in Brain-Derived Neurotrophic Factor and Insulin-Like Growth Factor which results in positive changes in the brain, such as the promotion of neurogenesis, synaptogenesis and angiogenesis, and improved brain structure and functional connectivity [17].
Recently, it has been hypothesised that an even more efective strategy to preserve cognitive functioning in older adults is to combine PA (e.g., aerobic treadmill walking) with CA (e.g., (computerized) cognitive training).Examples of combined physical and cognitive activity (PA + CA) are doing memory exercises while walking on a treadmill [18], exergaming [19], or sequentially combining physical training and cognitive training [20][21][22].Indeed, three metaanalyses concluded that larger cognitive gains can be achieved with cognitively enriched PA intervention programs, compared to PA programs without cognitive enrichment (i.e., Hedges' g in the three meta-analyses ranging from 0.15 to 0.24) [23][24][25].Although most studies found no additional efect on cognitive functioning of PA + CA in comparison with CA alone [23][24][25], PA + CA also fosters benefts for physical function (i.e., functional mobility), which is not the case for CA alone [23].Physiologically, it is assumed that PA and CA have a synergistic impact on neuroplasticity, in which PA facilitates neuroplasticity (e.g., through neurogenesis and synaptogenesis) and CA guides the neuroplasticity by promoting the survival and integration of newly formed neurons [26][27][28][29][30].
A major shortcoming of current research on PA + CA interventions is, however, that most studies have been conducted in controlled laboratory settings [23][24][25].To combat the increasing rate of cognitive decline and dementia in the aging population, real-life (i.e., in a more natural, everyday setting, as opposed to in controlled laboratory settings), low-cost, and scalable PA + CA programs that are easily accessible to the majority of the older population are needed.Recent research focused on home-based PA + CA programs [21,22,31].Tese home-based programs are either complete individual programs [21] or combine a number of group and (home-based) individual sessions [22].Nevertheless, Zhu et al. [25] found larger efects for group-based PA + CA interventions in comparison with individual PA + CA interventions.Furthermore, social engagement has also been shown to be linked with a lower risk of dementia [11,32].Additionally, it has been suggested that performing the cognitive and physical activity simultaneously might be important for the synergistic efects of PA + CA interventions [27].Indeed, the previously mentioned meta-analyses all found simultaneous training to be more benefcial for cognitive functions compared with sequential training [24,25] or exergaming [23].
Terefore, a real-life, group-based, simultaneous PA + CA intervention, more specifcally a cognitively enriched walking program for older adults (i.e., aged 65 years and above), "Take a walk with your brain", was recently codesigned using two complementary methodologies: (1) a multistage Delphi study with academic experts in the feld of cognition, physical activity, and aging and (2) a survey study in older adults and walking coaches.Tis entire conceptualization process has been described in our earlier publication [33].Tis newly developed cognitively enriched walking program consists of supervised groupbased cognitively enriched walking sessions (i.e., simultaneously walking and performing cognitive tasks).
Te current paper reports on the acceptability and feasibility of the "Take a walk with your brain" program in community-dwelling older adults aged 65+ years.Tis study was two-phased, focusing on the evaluation of performing cognitive tasks while walking (Phase I and Phase II), and of the cognitively enriched walking program as a whole (Phase II).Specifcally, it was of our interest to know how the participants perceived the cognitive tasks and the program, and what aspects of the program were perceived as the most important to them.Te research questions were as follows:

Study Design.
We conducted this acceptability and feasibility study in two phases.Phase I was a preparatory phase during which walk-along interviews (i.e., questions posed while walking) with one or two older adults at a time were conducted to evaluate the feasibility and acceptability of the cognitive tasks conceptualized by Marent et al. [33].In Phase II, the group-based cognitively enriched walking program was piloted to evaluate the feasibility and acceptability of (i) the cognitive tasks (performed in group as opposed to alone or in pairs in Phase I) and (ii) the group program in general (i.e., a more general evaluation of performing cognitive tasks in group while walking, supervised by a coach).To obtain a comprehensive evaluation of the cognitive tasks and the group-based cognitively enriched walking program, a mixed-method embedded study design was used [34].Tis design typically complements or elaborates on quantitative data with qualitative data.In the present study, rating scales were used to evaluate the cognitive tasks (Phases I and II) and the cognitive walking sessions (Phase II) (quantitative).Open-ended questions in questionnaires (Phases I and II) and focus groups (Phase II) were used to obtain deeper insight in the underlying reasons of participants' ratings and their experiences (qualitative).
Conducting the present study in two phases was an unforeseen amendment to meet COVID-19 regulations.Originally, this study was planned to take place in the summer of 2020.To meet the COVID-19 restrictions, the design was changed from an intended pilot testing in group, to a two-phased design.Phase I consisted of walk-along interviews in the fall of 2020, as these met the COVID-19 restrictions in force at that time.Phase II was a group-based pilot testing conducted in the fall of 2021, after the COVID-19 restrictions were lifted.

Participants. Te inclusion criteria for participation in
this study were being (1) 65 years or older, (2) Dutchspeaking, (3) able to walk for approximately one hour, and (4) reporting no severe cognitive, mental, or physical disorders.Recruitment was done separately for both phases by means of convenience and snowball sampling.As a part of an educational assignment, bachelor students Physical Education and Movement Sciences at two universities each recruited two older adults within their personal environment for the walk-along interviews in the period of November-December 2020 (Phase I).For the group-based program (Phase II), participants were recruited in November 2021 through the distribution of an (online) information leafet via organizations for older adults and an existing database of older adults interested in participation in studies of our research groups.In both phases, the aim was to recruit a diverse study sample with participants of diferent age, gender, and sociodemographic background.All participants provided written informed consent.Tis study was approved by the Ethical Committee Research UZ/ KU Leuven (S63305) and the Ethical Committee of Ghent University Hospital (2019/1045 BC-5773) and was carried out according to the guidelines for Good Clinical Practice (ICH/GCP) and the Declaration of Helsinki.Data collection took place between November and December 2020 for Phase I and between November and December 2021 (questionnaires) and January and February 2022 (focus groups) for Phase II.

Phase I.
During each walk-along interview, older adults (i.e., alone or in pairs) walked for approximately 60 minutes with an interviewer and performed two or three cognitive tasks.Te cognitive tasks were randomly assigned across participants.An overview of the cognitive tasks can be found in Table 1 (for detailed descriptions, see the article of Marent et al. [33]).A standardized protocol for each cognitive task was prepared for the interviewers.It included a description of the content, instructions, materials, required preparations, and general attention points based on input from the developmental stage of this project [33].Every walk-along session started with 10-15 minutes of brisk walking, after which the instructions for the frst cognitive task were communicated, and the participant(s) performed the cognitive task.After performing the frst task, participants were questioned about how they experienced performing the cognitive tasks by means of a structured walkalong interview consisting of rating scales and open questions (for more information, see infra, Quantitative program evaluation measures).Te same process was repeated for the second and, if applicable, third cognitive task.At the end of the walk-along interview, there was some time for relaxed walking (i.e., a cooling-down).In total, about 15-20 minutes per 30 minutes of the walk were spent on the performance of the cognitive tasks.Participants' responses to all questions and general sociodemographic information of the participant were registered by a researcher on a standardized response form.

Phase II.
Before starting the group-based cognitively enriched walking program, participants were asked to complete an online questionnaire to collect sociodemographic information, general health-related information, information on their level of physical activity, psychosocial health, and their subjective perception of their cognitive functioning (see infra, Sociodemographic and general healthrelated measures).A cognitive test battery and accelerometery were used in a subsample to confrm their feasibility for use in the future evaluation of the efectiveness of this program in a randomized controlled trial.As this goes beyond the scope of this paper, we will not report on this.
Participants in Phase II took part in six sessions of the cognitively enriched walking intervention in a group of approximately ten older adults.Tere were two walking groups: one in the city of Ghent (n = 10) and the other in the city of Leuven (n = 9).Te sessions were organized with a frequency of twice a week over a total time period of three weeks, in November-December 2021.Tey were supervised by certifed walking coaches who completed a formal Participants try to repeat the list in the same, reverse, or alphabetical order.

N-back
A list of letters, words, or numbers is read; participants must respond with a predefned signal (e.g., shouting "yes") when a letter, word, or number was already previously mentioned

List learning
A variety of possible lists are studied, and participants try to repeat them at the end of the walk Stimulus-response Participants must respond to a predefned stimulus in a certain way Ballgames Participants must remember the order in which the balls are thrown.Te complexity can be increased by using more than one ball or adding rules.
Note. a "Word fuency" is the same cognitive task as "Words starting with a particular letter" in the article of Marent et al. [33].
training of "Wandelsport Vlaanderen" (Walking Federation Flanders), meaning they had already developed the necessary competences to guide walks before participating in this study.Te two groups had diferent coaches, but the same coach supervised all six sessions for each group.After each of the six walking sessions, participants were asked to complete a program evaluation questionnaire consisting of rating scales and open-ended questions (see infra, Quantitative program evaluation measures).Te attendance was registered by a researcher (who was present during all sessions).After the six sessions, focus groups were organized separately for participants of both walking groups in order to gain an indepth evaluation of the cognitively enriched walking program.By combining questionnaires and focus groups, potential bias caused by social desirability efects was reduced.
As this was a real-life program, the settings difered from a recreational park to more urban settings.Each session lasted approximately 60 minutes and, as conceptualized by Marent et al. [33], consisted of three parts: (1) a warm-up of 5-10 minutes (brisk) walking, (2) about 15-20 minutes of cognitive tasks per 30 minutes of walking (i.e., two to three cognitive tasks), and (3) 5-10 minutes relaxed walking.As it was not the aim to compare evaluations of the cognitive tasks between the two groups, it was most efcient to let them be evaluated by only one group.Terefore, the cognitive tasks were divided into 11 combinations of two or three cognitive tasks in a way to stimulate diferent cognitive functions within each session.Both groups had the same introductory session with the aim to start of the program and getting to know each other while performing cognitive tasks.For instance, participants had to remember facts about each other in the cognitive task "Facts and titbits."Te remaining fve sessions were diferent for the two groups.An overview of the combinations of tasks can be found in Table 2, as well as information on which group evaluated which session.
Before the start of the sessions, the coaches received a detailed description of all cognitive tasks including an explanation of the task, instructions, duration of the task, possible variations, materials needed, preparations needed, how to guide the task, and important considerations (for an example, see Supplementary File 1).First, they received this digitally, so they could read this in preparation of a face-to-face meeting with the researchers during which all cognitive tasks, how to combine these tasks with walking, and any questions and concerns the coaches had were discussed.Te face-to-face meeting was organized separately for the coaches of the two groups and lasted approximately 4 hours.After this meeting, the coaches received a printed version of this manual.To use as a prompt during the walking sessions, the coaches also received summary cards which consisted of a checklist and the diferent parts of the walk (e.g., frst approx.10 minutes brisk walking, then cognitive task 1, cognitive task 2, and at the end approx.10 minutes relaxed walking; for an example, see Supplementary File 2).During each session, the coach explained and guided the correct execution of the cognitive tasks.One of the researchers was present during all sessions to ensure correct adherence to the intervention protocol.Tis served as a form of fdelity check for the implementation of the intervention.If needed, the coach and researchers had a short meeting before and/or after each session, in which potential difculties or questions that came up during the preparation or execution of the session could be discussed.If necessary, small changes were made accordingly (e.g., a cognitive task was prepared to be more difcult than planned based on feedback of the participants, or a task was changed from a written to a verbal task because of practical considerations).

Sociodemographic and General Health-Related Measures.
Tese data were gathered for descriptive purposes only.All participants (Phases I and II) were asked to provide their date of birth, gender, current marital status, and highest educational degree.Phase II participants were additionally asked to provide their country of birth and current professional activity and also completed a baseline questionnaire consisting of several validated questionnaires which are explained in more detail below.
For the measurement of PA (Phase II), the Dutch version of the International Physical Activity Questionnaire Short Form (IPAQ-SF) [35] was used.Tis seven-item questionnaire with open-ended questions is one of the most used questionnaires to evaluate PA.Te IPAQ-SF was evaluated to have appropriate content validity and reliability in systematic reviews of van Poppel et al. [36] and Silsbury et al. [37], respectively.Furthermore, it is a brief and low-cost measure, making it an accessible tool to estimate the PA levels of participants.Categorical scores were calculated following the Guidelines for the Data Processing and Analysis of the International Physical Activity Questionnaire [38].
Subjective cognitive functioning (Phase II) was assessed using the Dutch version of the Cognitive Failure Questionnaire (CFQ), which has 25 questions (e.g."Do you have trouble making up your mind?") on a fve-point Likert scale going from "Very often (4)" to "Never (0)."Te CFQ is the most widely used questionnaire to measure subjective cognitive failures [39] and has been shown to be a reliable measure [40].It is a measure of psychological distress related to cognitive difculties, rather than a valid measure of objective cognitive defcits.Subscales can be derived, but according to recent research recommending to only use the total score because the CFQ likely represents a single underlying construct [40], in this study the total score was used.A higher total CFQ score indicates more frequent cognitive errors reported by the participant [41][42][43].

Quantitative Program Evaluation Measures
2.5.1.Phase I.In Phase I, participants were asked to rate each cognitive task in terms of feasibility (i.e., "I feel capable of performing this task correctly") and enjoyment (i.e., "I enjoy this task") making use of fve-point rating scales (from "Totally Disagree (0)" to "Totally Agree (4)," middle point: "Neither Agree, Nor Disagree (2)").Tis information was registered by a researcher on a standardized response form.

Phase II.
In Phase II, participants evaluated both the cognitively enriched walking sessions and the cognitive tasks by means of a questionnaire after each cognitively enriched walking session.To gain a more nuanced impression of participants' experience, participants were instructed to rate every cognitively enriched walking session in general (i.e., "How would you rate the overall session?"), on an 11-point response scale (i.e., "Not good at all (0)" to "Very good (10)," no middle point was defned).Furthermore, the cognitive tasks were evaluated on 11 rating scales, namely, feasibility, enjoyability, difculty, challenge, competition (i.e., during the cognitive task), meaningfulness (i.e., of the cognitive task), interaction (i.e., with other participants, during the cognitive task), appropriateness for the combination with walking, appropriateness for the age group, perceived positive infuence on the brain, and clarity of instructions (i.e., given by the coach).An 11-point response scale going from "Totally Disagree (0)" to "Totally Agree (10)" was used (the middle point of the response scale was not defned).In these evaluation questionnaires, the cognitive tasks (1) "Buzz it" and "Problem solving" as well as (2) "Remember the route" and "Quest with environmental cues" were performed at the same time and therefore evaluated as one task.
Furthermore, attendance was registered by the researcher present during all sessions.

Qualitative Program Evaluation Measures
2.6.1.Phase I.During the walk-along interviews, participants were asked to verbally explain what could be done to make the cognitive task more enjoyable or feasible.Responses of the participants were registered by a researcher on the same response form as for the quantitative evaluation of the cognitive tasks.

Phase II
(1) Open-Ended Questions.In addition to the quantitative evaluation of the cognitively enriched walking session and cognitive tasks, three open-ended questions were completed Note.In italic is indicated which walking group evaluated the session. 6 Journal of Aging Research after each session (i.e., "What did you like most about today's session?," "What did you like least about today's session?," and "How could the session be improved?").
(2) Focus Groups.To gain a deeper understanding of the experiences of the participants of Phase II regarding the feasibility and acceptability of the cognitively enriched walking program, focus groups were conducted separately for each walking group.Te focus groups took place in January and February 2022 and were each moderated by two researchers.A semistructured interview guide was developed for the focus groups.Both focus groups took between 90 and 120 minutes and were audio recorded.Before starting the recording, participants agreed to the focus group being recorded.[43].Median, range, and frequencies were used to evaluate ratings of the cognitive tasks (Phases I and II) and the cognitively enriched walking sessions in general (Phase II).For Phase II, the best (i.e., highest median and smallest range) and least (i.e., lowest median and widest range) positively evaluated cognitive tasks were discussed.Furthermore, the mode was calculated for all cognitive tasks and rating scales of Phase I and Phase II.Tese values are not reported in the paper as they do not difer much from the median (which we do report), but can be found as Supplementary Files 3 (rating of cognitive tasks-Phase I), 4 (rating of cognitive tasks-Phase II), and 5 (rating of cognitively enriched walking sessions).

Qualitative.
Data from the open-ended questions from the walk-along interviews (Phase I) were coded by two researchers independently.Any disagreements were discussed with a third researcher to reach consensus coding.Tis content analysis was performed in SPSS.In the results section, counts are provided to quantify the number of times a (sub)code was used.Te fnal coding tree can be found in Table 3 and was drafted deductively based on the questions asked during the walk-along interview and adapted inductively (i.e., while coding).Qualitative data from the program evaluation questionnaires (Phase II) were briefy summarized.Te audio recordings of the focus groups were transcribed verbatim and coded by two researchers using QSR Nvivo qualitative data management software.In case of disagreement, a third researcher was involved to reach consensus.Tis thematic analysis approach aimed to gain a deeper understanding of the feasibility and acceptability of and suggestions for improvement of the cognitively enriched walking intervention.Te coding tree (Table 4) was drafted deductively based on the interview guide used for the focus groups and adapted inductively.Te same coding tree was used for the data from both focus groups.

Phase I.
A total of 176 people expressed willingness to participate in Phase 1, of which 13 participants (7%) did not meet the inclusion criteria.Tus, 163 older adults participated in a total of 85 walk-along interviews (i.e., there were individual walk-along interviews and walk-along interviews in pairs).Te participants were on average 75.13 years old (SD � 6.26, range: 65-89), 58% was female, and 42% was male.Furthermore, 36% (n � 59) of the sample obtained a higher education degree, 40% (n � 65) obtained a secondary education degree, 18% (n � 30) obtained a primary education degree, and 3% (n � 4) obtained no degree.For the other 3% of participants (n � 5), the latter information was missing.

Phase II.
Twenty-two participants were enrolled in the group-based phase of the study and met the inclusion criteria, of which three dropped out (13.6%) before starting the intervention because of health issues (n � 2) or an acute family event (n � 1).Nineteen participants (i.e., nine in Leuven and ten in Ghent) started the three-week pilot intervention.Participants were on average 73.63 years old (SD � 5.51, range: 65-88 years), 63% of the sample was female, and 37% was male.Furthermore, 84.2% of the sample (n � 16) obtained a higher education degree, and the remaining 15.8% (n � 3) obtained at least a higher secondary education degree.Other sample characteristics can be found in Table 5.
Prior to the start of the intervention, the proportion with high, moderate, and low PA levels was 47.4% (n � 9), 36.8% (n � 7), and 15.8% (n � 3), respectively.Te mean total CFQ score of the participants (M � 34.6; SD � 12.5) was within the normal range , which is based on the sample of the Maastricht Aging Study (n � 1358) [43].Te mean T-scores on PROMIS short forms Depression (M � 51.0; 7.

Phase I.
Tirty-one of the 32 cognitive tasks that were evaluated had median rating scores of 3, 3.5, or 4 on the rating scale for feasibility ranging from "Totally disagree (0)" to "Totally agree (4)."Only the cognitive task "Problem Journal of Aging Research solving" received a median rating score of 2 for feasibility.In terms of enjoyability, all cognitive tasks obtained a median score of 3, 3.5, or 4, on a scale ranging from "Totally disagree (0)" to "Totally agree (4)."Tere was variability in perceived feasibility (Table 6) and enjoyment (Table 7) as indicated by the individual scores ranging from 0 to 4.  No session received a score below 5 on a rating scale of 0 "Not good at all" to 10 "Very good," on the question "How would you evaluate this cognitively enriched walking session?"Furthermore, ≥65% of the participants for all walking sessions rated the walking sessions with a score of 7 or higher.Median scores for the cognitively enriched walking sessions ranged from 7 to 10 on a total of 10 (Table 8).
Reasons for not attending a session were illness, conficting appointments, and self-isolation because of COVID-19.

Phase I. Te content analyses of responses to the openended questions during the walk-along session indicated
that that good weather conditions (n � 13), letting the walk take place in a quiet environment without many obstacles (n � 11), and the opportunity for social or group interaction (n � 3) were important for a positive evaluation of the walk.Reasons for a negative evaluation of the walk were bad weather conditions (n � 30) and having difculty walking long distances because of physical discomfort (e.g., knee pain or needing help to walk) (n � 5).When assessing specifc cognitive tasks itself in terms of enjoyment and feasibility, only having the feeling that the tasks stimulates self-efcacy by enactive mastery (n � 2) and fnding the difculty level of the task just right (n � 2) were mentioned to be a reason for a positive evaluation of a given cognitive task.
Perceiving the cognitive task as too difcult (n � 25) or too easy (n � 22) and not fnding the cognitive task suitable to perform while walking (e.g., because one cannot relax or talk enough) (n � 13) were the most common reasons for a negative evaluation of a cognitive task.In addition, not seeing the beneft of the tasks or feeling like the tasks were unnecessary or not useful (n � 8), the absence of competition (n � 8), the feelings of shame (e.g., because other people watch you doing the task) (n � 6), fnding the task too boring (n � 5), and fnding the task too childish or not appropriate for older adults (n � 5) were also mentioned frequently as reasons for a negative evaluation of a cognitive task.Lastly, another reason for not liking a task or not fnding a task feasible was not feeling safe because of fall risk while performing the task (n � 9), because of trafc (n � 3), or because of uneven ground (n � 1).

Phase II
(1) Open-Ended Questions.Mostly information about practical aspects of the walks came up (i.e., starting place or weather conditions).Getting to know each other and social interaction were indicated as aspects participants liked the best about the sessions.Te walking speed (i.e., too slow), walking distance (i.e., not far enough), weather conditions (i.e., rain or cold), and unclear instructions about the cognitive tasks were the main aspects participants mentioned to like least about the sessions.
(2) Focus Groups.All participants of the walking group in Leuven (n � 9) were present during the focus group, while only fve out of ten participants of the walking group in Ghent were present during the focus group.Results for the   12 Journal of Aging Research diferent themes that were covered during the focus groups are described below.

Journal of Aging Research
(a) Te Content of the Cognitive Tasks Overall, most participants perceived the cognitive tasks to be less difcult than they had expected.About half of the participants agreed that the cognitive tasks were too easy for them and even felt as if their capacities were underestimated.Other participants perceived part of the tasks as difcult and part of the tasks as not difcult at all.Only one participant mentioned that some of the tasks were too difcult, but that he tried to participate, nevertheless.One participant suggested making some tasks more diffcult by extending the recall phase in memory exercises (e.g., repeating the recall at the beginning of the next walking session).She would also like more attention to be paid to the strategies they used to solve cognitive tasks, in order to get the opportunity to learn from each other.Other participants would like to have the option to choose a certain level of difculty (e.g., diferent walking groups based on difculty or diferent levels of difculty for each cognitive task).

"But for me it was too difcult. I have often told myself 'I can't keep up with the others, that's that.'" [researcher "So sometimes it was too difcult for you. Would you prefer easier tasks?"] "No, no, I tried to participate. Tat's no problem for me." (G006, male, 88 y)
Most of the participants reported that it was feasible to perform the cognitive tasks while walking.However, they mentioned that sometimes they automatically stopped walking to chat or perform a task and that motivational encouragement of the coach was needed to keep them walking.It was also mentioned that tasks that included writing and were inherently walkingunrelated (e.g., "Mental Arithmetic") were not or less feasible to perform while walking.Tasks needing communication or interaction between participants were, according to these participants, the most feasible and fun tasks.In order to make the tasks more feasible to perform while walking, some participants suggested including more verbal tasks instead of tasks that need reading or writing.Furthermore, they preferred tasks to refect daily life, or to make use of more relevant stimuli (e.g., remembering the age of the other group members).Tere was a distinction between perceptions of interand intra-individual competition.Regarding inter-individual competition (e.g., trying to recall the most words, or to be the quickest to solve a riddle), opinions were divided in both groups.Some participants mentioned to be very reluctant to inter-individual competition, while others mentioned that they liked to compete with others.On the other hand, it was mentioned that some like intra-individual competition, namely, monitoring the evolution in their own performance or comparing themselves to age-related norms.Participants who liked either inter-or intraindividual competition both mentioned that this could be a motivator for them.For most of the participants, the framing of the cognitive tasks was very important.Tey wanted to know why they were doing certain tasks.Although an explanation about why each cognitive task was important was already given, most participants of both groups would like more background information, also about the general aim of the program.

"I want to know why we do every task." [. . .] "Like, is it to keep us busy, or is it evidence-based?" (G004, female, 65 y)
Participants indicated that it is important that the coaching style should be sufciently encouraging to make them perform the cognitive tasks the right way and to keep walking.A humoristic, friendly, and inclusive (i.e., trying to engage all participants) coaching style was liked by the participants.However, they did not like it when the coach would try to solve the cognitive tasks for them.Te participants mentioned that they do not mind the age of the coach.Other preferred characteristics of the coach were not mentioned.(d) Characteristics of the Cognitively Enriched Walking Program Most of the participants agreed with the proposed duration of one walking session, which is 60-90 minutes.Some participants, however, mentioned that they would like longer walking sessions, depending on the season (e.g., in winter 60-90 minutes is enough, in summer longer walks are preferred).Te participants did mention that a duration of less than 60 minutes would be too short and not worth the efort of coming to the starting point and organizing a group walk.
Opinions were divided about the frequency of the cognitive walking sessions when the program would be held for a longer time period (i.e., six or nine months).A substantial part of the participants mentioned that two times a week was too much, and that one session a week was preferred.Others agreed with two sessions a week, or preferred only one, but a longer session.One participant mentioned that she would even like three sessions a week.A reason for preferring one session a week (i.e., coming from one participant) was that she already has too many other activities, and another participant mentioned the long distance from his living place to the starting point of the sessions.Living near the starting point, the group dynamics (i.e., a "nice" group), and spontaneous social activities after the walking sessions (e.g., having a cofee together) were mentioned by one participant as reasons for wanting to engage in two sessions a week.Because of the participants' reluctance to attend two or more sessions a week, which was advised by experts in the previous stage of this project [33], we asked the participants' opinions on the possibility of individual (nonsupervised) cognitive walking sessions to supplement the group sessions.Most participants were enthusiastic about this, as they could ft this into their already existing habits.Tey did mention that they would like the cognitive tasks to be low threshold (e.g., simply repeating a task that was performed during a cognitive walking session in group) and real-life refecting and to be able to choose to do these sessions alone or in company.However, some participants were doubtful about their long-term adherence to these individual sessions.
Regarding the duration of the program, some participants were reluctant to engage for a longer period (i.e., six or nine months).Some participants mentioned that this is too long, and others mentioned their other activities as a reason for not being able to engage themselves for a longer period.
"Driving here by car was okay for two times a week for three weeks.But for a longer period, I wouldn't do that."(L005, male, 66 y) (e) Organization of the Program While some participants preferred communication through e-mail, others preferred contact via telephone.Some participants mentioned that they liked the WhatsApp group (i.e., communication app on smartphone) that was organized for the group in Leuven to facilitate communication between coach and participants.Regarding safety, the participants in both groups mentioned that a place with few cyclists, joggers, or other trafc feels safe for them.Almost all participants preferred to walk in nature instead of in the city center.Te availability of parking spaces was mentioned as an important factor when choosing the location for the cognitive walking sessions; public transport or other modes of transportation were not mentioned.Weather conditions were mentioned as an important factor by some participants.While the participants preferred not to walk in the rain, some of them indicated that they did not mind it, noting that it is possible to dress accordingly.
14 Journal of Aging Research (f ) Composition of the Walking Groups Because of diferent physical ftness levels, the ideal walking speed was not the same for everyone.Some participants did not experience this as a problem, other participants mentioned that it is important for all members of a walking group to have a similar walking speed (i.e., so no one has the feeling they have to walk too slow or too fast).It was also suggested that it might be better to have diferent groups for diferent ftness levels.Te participants mentioned that the age of the group members does not matter as some older individuals are more ft than younger ones.Regarding the group size, all participants preferred a group of eight to twelve people and they thus agreed that the size of the walking groups they were in now was optimal.

Discussion
Te aim of this study was to evaluate the feasibility and acceptability of the cognitively enriched walking program for community-dwelling older adults.In general, the cognitive tasks showed adequate feasibility and enjoyability in both the walk-along interviews (Phase I) and the group-based program (Phase II).Median scoresof 2-4 for feasibility and 3-4 for enjoyability on a total of 4 were obtained in Phase I.In Phase II, median scores of 8-10 for feasibility and 7-10 for enjoyability on a total of 10 were obtained.Also the meaningfulness, challenge, interaction, competition, appropriateness for combining with walking, appropriateness for the age group, perceived positive infuence of the brain, and clarity of the instructions of the cognitive tasks were overall positively evaluated in Phase II with medians ranging from 5 to 10 on a total of 10.Furthermore, the cognitively enriched walking sessions were positively evaluated with medians of 7-10 on a total of 10.Moreover, in Phase II, an average adherence of 87.7% (or 5 out of 6 sessions) was obtained, which confrms the feasibility and acceptability ratings.Te cognitive tasks, as well as the cognitively enriched walking program, are thus evaluated to be feasible and acceptable.Tis suggests that further evaluating the efects of the group-based cognitively enriched walking program is likely to be achievable in the real world.However, results also showed that some adaptations need to be made to the cognitive tasks as well as to the group-based program itself to be ready for execution and evaluation of its efects by means of a randomized controlled trial (RCT).

Cognitive Tasks (Phases I and II).
Most participants provided positive ratings for the cognitive tasks in terms of enjoyment and acceptability.However, cognitive tasks during which writing was needed (e.g., "Mental arithmetic") were changed from written to verbal tasks in the subsequent RCT study.Tis was done to meet the suggestion of participants that tasks needing social interaction or verbal discussion instead of tasks that need writing or reading are better suited to perform while walking in group because they interfere less with the natural fow of the walk.Furthermore, as a response to the participants of Phase II mentioning they like tasks better when they make use of stimuli relevant to their daily life, we emphasized this in the RCT manual for coaches by adapting the examples we give.For instance, for the cognitive task "List learning," we suggested trying to remember things on the shopping list of the participants, in addition to trying to remember street names they encounter during the walk.
Notably, low median scores (i.e., lower than 5 on a total of 10) were obtained only for the difculty of the tasks, showing that most of the tasks were not difcult (or too easy) according to most of the participants.Tis was also refected in the results of the focus groups after Phase II of this study, in which some participants even mentioned that they felt as if their capacities were underestimated.Moreover, participants of Phase I mentioned tasks being too easy as a reason for a negative evaluation of a given task.It is however important to note that there was a large variability in individual evaluations of difculty, and the sample of Phase II was highly educated and generally reported few subjective cognitive failures.Furthermore, Gheysen et al. [24] suggested that adequate cognitive challenge is important to obtain cognitive efects.It is consequently of utmost importance to diferentiate during the cognitive walking session (i.e., to make it possible to adapt the cognitive task to meet each participant's individual capacities).Although eforts to make this possible were already made by describing diferent variations of the cognitive tasks in the manual for the coaches, even more specifc options to tailor cognitive tasks were provided in the manual for the coaches to be used in the RCT.Tis could imply that it is necessary to perform cognitive tasks in smaller groups, based on the individual capacities of the participants.However, to ensure the core concepts of the cognitive tasks remain the same even when tailoring the difculty level (e.g., by having to remember more or less words or facts), the manual for the RCT also indicated which are the "basic building blocks" for each task.Te coaches were instructed not to change these aspects.For example, the basic building blocks of the cognitive task "Facts and titbits" are the following: (1) exchanging information with other participants while walking, (2) memorizing new information while walking, and (3) retrieving the newly acquired information from memory while walking.
Furthermore, although there was no opposition against competition among the participants (i.e., during the focus groups, Phase II), there was a large variability in perceived competition ratings for all cognitive tasks (i.e., range of individual scores of 0-10).Tus, older adults might just have diferent perceptions and preferences with regard to competition.Previous research showed that competition can be a motivator for PA participation [51], but that women may be less likely to prefer competition than men [52].Hence, competition will continue to be included on an occasional basis, as recommended by Marent et al. [33].Specifcally, the coaches in the RCT were advised to include competition carefully, to prevent conficts or a bad atmosphere and to make intra-individual competition possible.

Journal of Aging Research
One cognitive task, "N-back," that was evaluated during the walk-along interviews, was left out when evaluating the group program.Te researchers decided upon this based on the fndings of Marent et al. [33], the experience of the researchers that is was not easy to make this task enjoyable to perform in group, and the relatively low median enjoyability score obtained in Phase I of this study.Furthermore, it is important for the practical application of the program to include tasks that are perceived to be enjoyable.Tis is in line with literature showing that enjoyment is a reason for participation in PA for older adults [53,54].Tis task was thus also left out when evaluating the efectiveness of the program.

Cognitively Enriched Walking Program (Phase II).
Overall, the cognitively enriched walking sessions were positively evaluated (i.e., medians of 7-10 on a total of 10 and no score below 5).Tis is encouraging, as recent research has considered acceptability as an important factor that may infuence adherence and contribute to the efectiveness of the intervention [55][56][57].Furthermore, enjoyment could motivate older adults to undertake and maintain PA [58].
However, participants did not perceive the walks as not physically challenging enough and most of the participants preferred a higher walking speed and longer walking distance.A possible explanation might be that participants were not given clear information about the expected walking speed and distance prior to signing up.To set more realistic expectations for the upcoming RCT study, it was communicated during recruitment that walking distance during a cognitively enriched walk of 60 minutes would be three to fve kilometers.Important to note, however, is that most of the participants in Phase II of this study were highly physically active at baseline.Tis could be explained by the well-known self-selection bias in PA trials, in which people who enroll are typically already physically active.For example, in an RCT by Sipilä et al. [22] focused on people not meeting the physical activity guidelines, 2,767 people were assessed for eligibility of which 806 (29%) had to be excluded because they were too physically active.Likewise, van Ufelen et al. [59] did not manage to include people with low PA levels in a one-year community-based PA program to improve cognitive function and therefore also included more active people and adjusted the program to cater for people of diferent PA levels.Te baseline PA levels of Phase II participants may have infuenced their opinion about the preferred walking speed and distance.Given that it is a group program, diferentiating in walking speed or distance on an individual level is very challenging.When implementing this program on a larger scale (i.e., after the efect evaluation), diferent walking groups for diferent levels of ftness levels could be created.Of course, it is important to try to physically challenge everyone sufciently as earlier work already showed the importance of progressive increase of difculty of physical exercise to induce cognitive efects [60].Furthermore, it became clear that participants tended to slow down or even stopped walking while performing the cognitive tasks.Tis is consistent with the fnding that gait speed is negatively impacted by dual-tasking in healthy older adults, as shown by a meta-analysis including 22 studies [61].Given the observations made in this study as described above, the following elements were added to the manual for the RCT: (1) as the aim of the intervention is to simultaneously perform cognitive tasks while walking, the importance of keeping the participants moving was emphasized in the manual and this was also highlighted during the program education session for the coaches in the RCT; (2) ensuring everyone could walk at a sustainable walking speed while still being able to join the group-based walking program, an extra emphasis was placed upon the individual diferentiation in walking speed; participants walking faster could, for example, be instructed to proceed to a certain point on the route at their own speed and to return to the group when reaching this point; (3) ensuring the intensity of the activity increased, the coaches were instructed to progressively increase the walking speed over the intervention duration of six months.Furthermore, we recruited certifed walking coaches for the RCT (like in the pilot study), who have undergone a formal training.Tey therefore have the necessary competences to ensure all participants can maintain a walking speed which is sustainable for them, and demonstrate profcient skills in this regard.Altogether, the manual for the coaches to be used in the RCT was extended based on the observations made in this pilot study.As described above, basic building blocks and options for variation in difculty for all cognitive tasks and considerations for the physical part of the intervention were included in the manual.In addition to those changes, the manual was extended to incorporate information regarding the aim of the intervention, the basic principles of the cognitively enriched walking intervention, the practical organization of the sessions and strategies for ensuring a safe walking environment.
Regarding the practical aspects of the program, it was agreed upon by participants that a duration of 60-90 minutes for one cognitive walking session was ideal, especially keeping in mind the frequency of two group sessions a week.Some participants preferred longer sessions, but with a frequency of only one group session a week.Experts advised having at least two sessions a week to induce efects on cognitive functioning [33].A compromise solution could involve having two group sessions a week supplemented with one home-based individual session.Tis is in line with another combination of PA and cognitive training by Sipilä et al. [62], who also supplemented two group exercise sessions with a home exercise program and home-based cognitive training.Tis individual session was included in the subsequent RCT study by providing participants with "practice cards" that could be used when going for a walk on their own or for instance with their partner, (grand)children, or friends.Tese cards included the cognitive tasks performed during the group walks, adapted to make it possible to perform them alone, without needing extra equipment or a coach to supervise.With respect to the total duration of the program, participants were reluctant to engage themselves for a longer period (i.e., 6 or 9 months), mainly because combining it with other activities would not be feasible in the long run.16 Journal of Aging Research Te supervision of the sessions by a coach was considered a positive aspect of the program by the participants.Regarding the infuence of supervised (i.e., a researcher or instructor is present to give instructions) versus unsupervised interventions (i.e., the participant performs the intervention without a researcher or instructor being present), Gavelin et al. [23] did not fnd a moderating efect of supervision for PA + CA interventions.However, only 4 studies did unsupervised training (versus n � 37 for supervised training), and thus these results should be treated with caution [23].Framing the cognitive tasks is important as the participants mentioned they want to understand why they are doing certain tasks.Tis can support the basic psychological need of autonomy, as described in the selfdetermination theory (SDT), which can positively impact exercise participation [63].Te group setting was also mentioned as an advantage of this program, as social interaction could be a motivator to be physically active.Tis is in line with recent research indicating that social factors such as spending time with others [52] or having an exercise partner [58] might improve participation in PA interventions and therefore lead to better results of these interventions (i.e., greater improvements in PA levels).Accordingly, Zhu et al. [25] found larger efect sizes for the improvement of cognitive functioning in group-based PA + CA interventions, compared with individual or mixed interventions.Given the importance of the social aspect, a measure for social support and loneliness was included when evaluating the efects of the cognitively enriched walking program.

Most Important Factors of a Feasible and Acceptable
Cognitively Enriched Walking Program.Te most important factors for a feasible and acceptable real-life cognitively enriched walking program, identifed in this study, are as follows: (1) the program should be sufciently challenging for every participant both cognitively as well as physically, (2) social interaction should be encouraged as this could be a motivator, (3) solving of the cognitive tasks should mainly be verbal instead of written, (4) cognitive tasks should make use of stimuli refecting daily life, (5) the rationale of performing the cognitive tasks should be explained, (6) cognitive tasks should be conducted in group, (7) the cognitively enriched walking program should not have more than two group sessions a week, and (8) the cognitively enriched walking program should be supervised by a trained coach.

Strengths and
Limitations.Tis study had several strengths.Conducting a pilot study before the start of anRCT in a large sample is a strength, since pilot testing often provides ideas and approaches that may not have been foreseen before conducting the efect evaluation study (RCT), and may result in adaptations or redesign of the intervention that may increase the chances of fnding efects in the RCT.Tis is especially relevant when translating interventions from controlled to real-life settings, as feasibility and enjoyability will infuence participation rate and adherence.Secondly, the mixed-methods design (i.e., using both quantitative and qualitative data) is a strong design which allowed a deeper investigation of the underlying reasons for the feasibility and acceptability ratings and the experiences of the participants, making it possible for the researchers to better adjust the program to the specifc needs of the target group.Also, doing individual walk-along interviews had several benefts as it allowed a one-on-one conversation with the participant, which limited potential social or group biases.Furthermore, these interviews were performed during the walk and right after the moment of doing the cognitive tasks which minimized potential memory or recall biases.Finally, although breaking the study apart into two phases was an unforeseen amendment to meet COVID-19 regulations, it enabled us to gain detailed insight in potential diferences between the experience of performing the cognitive tasks individually at one time point versus performing the program (i.e., the combination of 2-3 cognitive tasks performed while walking) in group for a longer period, but also to see similarities in the feedback that was given which added more certainty to the answers being representative for the general opinion of the target group.Moreover, the two-phased design made it possible to make further adjustments to the program before conducting it in a group.
Tere were also some limitations to this work.First, Phase II of the study (i.e., group walks) was conducted in a limited sample (n � 19) which might hinder generalizability of the results to the wider population of healthy older adults.However, many diferent guidelines for sample sizes for pilot studies exist, indicating that sample sizes of 10 [64] to or 30 or more [65] are needed.Although Teresi et al. recommend a sample size of 30 or less or 30 or more when using qualitative or quantitative methods, respectively [65], we are not aware of specifc guidelines for sample size in a pilot study using mixed-method to evaluate the feasibility and acceptability of an intervention.Furthermore, Teresi et al. emphasized that the sample size should be based on practical considerations, such as budgetary and time constraints [65].For the present study's aim, which was to evaluate feasibility and acceptability-not to estimate efect sizes or make between-groups comparisons-and taking into account the cognitive tasks were already evaluated by 163 individuals in Phase I, the sample size of n � 19 for Phase 2 allowed us to gather meaningful data using both quantitative and qualitative methods.Tis comprehensive evaluation allowed us to detect potential issues in feasibility and acceptability of the program before fnalizing the program manual and start the recruitment phase for the RCT.Tis sample was also highly educated and highly physically active, which implies that the results and suggestions that were made are less representative for people with a lower educational degree or a lower PA level.Second, we excluded participants based on self-report of having a cognitive disorder and did not use a screening test to rule out cognitive impairment in either phase of the study.Tird, in both phases, interviewers and coaches only received a short training which might have impeded the standardized execution of the program and instructions to the cognitive tasks.Te limited training of the coaches may however add to the ecological validity of our fndings.Furthermore, in Phase I, the walk-along interviews were conducted by several Journal of Aging Research interviewers who only received a document with instructions and no individual training by the research team, which might have caused variability in the way cognitive tasks were explained and, consequently, experienced by the participant.
Fourth, the open-ended questions completed by participants in Phase II were written in positive tones, which might have lead participants to answer more positively.
Finally, as with most research conducted during 2020-2021, last-minute changes had to be made in the study protocol because of the restrictions that were imposed by the Belgian government to prevent the spread of COVID-19.As mentioned in the methods section, this resulted in a twophased design, but it might also have impacted the willingness to participate in a study with total strangers.As such, individuals that were more cautious, were at a higher risk of coronavirus complications, or lived with a family member that was at higher risk, might not have participated.Tis was also the reason why bachelor students recruited and interviewed participants of their own network for the walk-along interviews (Phase I), which may have caused a bias towards more positive evaluations because participants might not have wanted to disappoint the interviewer.Furthermore, due to postponing the group-based testing because of COVID-19 regulations and because of our funding timescale, there was no other option than to conduct Phase II in the colder months of the year.We however see this as a strength since this adds to the ecological validity and the results indicate that, also in the colder months, this program is feasible and acceptable.Nonetheless, it needs to be noted that Belgium has a mild climate all year round and that an outdoor walking program may be less feasible in regions with much colder climates.

Future Research Directions.
Given the need for accessible, low-cost programs for the prevention of cognitive decline and promotion of optimal cognitive aging, real-life interventions like this one are increasingly relevant.Although research is growing in the area of healthy aging, real-life programs will only be adopted when feasible and acceptable to the end-users.As shown by our results, also contextual factors such as weather or walking environment are important in real-life programs, which is not the case in controlled settings.More real-life programs should thus be developed in cocreation with their end-users and include pilot testing in order to be able to compare or confrm our fndings.Furthermore, as this study sample of healthy older adults was highly educated and physically active, other, more vulnerable groups of older adults should be included in future studies as other factors might be more important for them.Additionally, these fndings are only of relevance to healthy older adults, and thus an intervention for older adults with cognitive decline (i.e., mild cognitive impairment or dementia) should be adapted to the needs of this specifc study population.Lastly, as this study focused on feasibility and acceptability, it did not provide data on whether or not the cognitively enriched walking program can mitigate cognitive decline.Terefore, further interventional research to evaluate the efectiveness of this real-life group-based cognitively enriched walking program is warranted.

. Conclusion
Overall, this study provides evidence for the feasibility and acceptability of this group-based cognitively enriched walking program for community-dwelling older adults.Te most important factors for a feasible and acceptable real-life cognitively enriched walking program are as follows: (1) the program should be sufciently challenging for every participant both cognitively as well as physically, (2) social interaction should be encouraged as this could be a motivator, (3) solving of the cognitive tasks should mainly be verbal instead of written, (4) cognitive tasks should make use of stimuli refecting daily life, (5) the rationale of performing the cognitive tasks should be explained, (6) cognitive tasks should be conducted in group, (7) the cognitively enriched walking program should not have more than two group sessions a week, and (8) the cognitively enriched walking program should be supervised by a trained coach.
Tese results warrant future research to establish the efectiveness of this program.In addition to the actual results of this study, the employed methodology is relevant for researchers and practitioners planning to pilot test the acceptability and feasibility interventions that have been adapted for use in real-life settings.

Table 6 :Table 7 :
Median and range of feasibility scores for all cognitive tasks rated in Phase I (n � 163).Median and range of enjoyment scores for all cognitive tasks rated in Phase I (n � 163).withclues + remember the route" (M = 10, range = 6-10).

Table 1 :
Overview of cognitive tasks.

Table 2 :
Temes of cognitive walking sessions and cognitive tasks (Phase II).
Note.Codes in italic are inductive codes.

Table 5 :
Sociodemographic information of participants in Phase II (N � 19).
(1) Evaluation of the Cognitive Walking Sessions.

Table 8 :
Frequencies and descriptive statistics of the ratings for the walking sessions (Phase II).Note.N � the number of persons that evaluated the cognitive walking session; the numbers in bold are the score(s) with highest percentage.

Table 9 :
Median and range of scores for all cognitive tasks on diferent rating scales evaluated in Phase II (n �