Effects of Aquatic Exercise on Executive Function in the Aging Population

Effects of Aquatic Exercise on Executive Function in the Aging Population Lori A. Sherlock Neurocognitive decline, including Alzheimer’s Disease and other forms of dementia, is considered to be the world’s fastest growing disease (Alzheimer's Association, 2011). Due to this escalation, research focused on determining causes, accelerants, impeding factors, and preventative strategies has become a focus of interest within the field. One of the principal points of study is the role that exercise plays in the maintenance or fortification against neurocognitive decline. Though there is a robust library of research focused on the effects of land-based exercise on cognitive function, currently there is no research that discusses the impact of aquatic-based exercise on these parameters. This mixed method study focused on identifying the effects of a 10-week aquatic exercise intervention on parameters of executive function in individuals aged 60 years or older. Additional research questions targeted changes in cardiovascular fitness, wellness, and psychosocial barriers as well as behavior change in relation to the incorporation of adult education, and accessibility to exercise. Thirty-four volunteers between the ages of 60 and 90 years were recruited for this study. All participants took part in three preliminary visits consisting of assessment of physical parameters (anthropometric measurements, 6-minute walk test, RHR, RBP), psychosocial mediators (barriers, self-efficacy, motivators, social support), and cognitive variables (CANTAB® testing). Participants were then grouped into matched pairs and randomly assigned to the control or intervention group. The control group agreed to not alter their physical activity status while the intervention group took part in a 10-week aquatic exercise program employing progressive overload and adult education concepts. At the conclusion of the intervention, all participants (n = 34) returned for their physiological, psychosocial, and cognitive post assessments. In addition to the post-testing, the intervention group also participated in a focus group to provide the researcher with qualitative data to associate with the quantitative findings. Following data collection, a 2-way ANOVA with a group (treatment versus control) by time (pre and post intervention) was utilized to examine quantitative findings. The qualitative data from the focus group was carefully reviewed multiple times for emergent themes while employing inductive and frequency analysis. Method triangulation was then performed as a means to gain further insight into the findings. The findings revealed that the aquatic exercise intervention did not have global effects on cognitive function or physiological parameters. However, a statistically significant (p = 0.014) change favoring the intervention group was found for the spatial working memory (SWM) between errors score. Qualitative and quantitative data converged to denote no global change to executive function while displaying improvements in cognitive parameters aligned with SWM. Statistically significant positive changes were observed in the DBP (p = 0.014) favoring the intervention group, however results from the 6-minute walk test as well as SBP and RHR only displayed positive trends without reaching statistical significance. Changes over time in body weight and composition between the treatment and control group were not statistically significant. Triangulation revealed compatibility of qualitative and quantitative trends for distance walked and global wellness improvements. A lack of commentary concerning changes in body weight and body composition reflected the negligent quantitative change in these parameters also denoting convergence of data. In relation to psychosocial mediators, no statistically significant interactions between the intervention and control groups over time were found. Initial survey results revealed very few perceived barriers, high motivation, sound social support, and high self-efficacy from both the intervention and control groups presenting a potential ceiling effect upon post-test findings. A statistically significant group effect in the control group was noted for social support showing a perceived reduction in social support. Qualitative data corroborated these findings for the intervention group with predominantly positive, voluminous responses in reference to all psychosocial mediators discussed. Barriers were accounted for yet traversed with solid coping strategies; motivation was high within multiple factors producing great motive for program commencement and continuation; self-efficacy was positively perpetuated throughout the course of the intervention via health outcomes and ability levels; and social support was strong through multiple cohort channels. The exercise intervention was built around an adult education framework consisting of (1) finding motivation to begin exercise, (2) begin integrating exercise that fits into individual lifestyles, and (3) maintain and gain on all fitness parameters. It seems that through the information provided by the focus group participants that a behavior change did occur for the vast majority of the intervention group. With 86% of the attendees devising a plan for continuation of physical activity in conjunction with multiple variations in lifestyle changes and benefit recognition, it seems that the intervention group may be newly initiated chronic exercisers. Qualitative findings denoting the intervention participants resolve to continue exercise may be due in part to their improved accessibility to exercise. Utilizing aquatic exercise as a gateway to provide knowledge, advance health and function, and improve self-efficacy while reducing barriers to exercise were all distinguishable reasons for using aquatic training as a precursor to other forms of exercise. Qualitative findings provide a more personal and complete picture of how aquatic exercise was able to offer the option of physical activity to those with the perception that they were not able to take part in exercise. In conclusion, this study revealed that aquatic exercise does positively affect selective components of executive function, cardiovascular fitness, and wellness. Whereas psychosocial mediators did not show improvement, the intervention groups’ maintenance of a positive association with these mediators following a 10-week aquatic exercise intervention is encouraging. Additionally, with the allowance of active participation in exercise via the aquatic medium, participants’ accessibility to exercise was promoted while the perceived improvements in physical ability endorsed a behavior change towards improved overall physical activity levels. Future research is needed to elaborate and further justify the use of aquatic exercise for improving physiological and cognitive parameters. Procedural alterations concerning frequency and duration of aquatic exercise sessions, inclusion of participants within the spectrum of cognitive impairment, the addition of a variety of cognitive function assessments, as well as comparing the effects of land versus water on all parameters should be explored. Additionally, the implication that SWM may experience greater alterations and advancements in novice exercisers and sedentary individuals should be examined.