Physical activity as non-drug modulates consider one of the most promising strategies to prevent or improve cognitive disabilities among elderly populations . It was reported that physically active people across their entire life minimize the incidence rates of dementia and cognitive difficulties [54–56]. Whereas many studies reported a lower rates of cognitive disorders among subjects who participated in higher levels of physical activity interventions than persons with lower scores of physical activity [57–58].
Recently, many research works revealed that physical exercise with moderate intensity produce remarkable higher levels of improvement in skills, mobility, and mood in both younger , and older adults . However little is known about whether the positive effect of moderate exercise on cognitive abilities, which occurs via modulating lipid profile and lipoprotein (a).
Therefore, the current research work aimed to investigate the probable correlation between anti-dyslipidemic mechanisms of exercise on cognitive abilities among 150 older adults participated in supervised aerobic training program for 24 weeks.
In the present study, the cognitive abilities of 150 older adults of both control and exercise group were measured using LOTCA scores, a cognitive evaluation test formed of 7-subsets variables. In older subjects participated in moderate aerobic exercise for 24 weeks, there was significant improve in cognitive performance via increase in all LOTCA 7-subsets variables compared to non exercised group. The data revealed positive significant correlations between the total LOTCA scores of older subjects and their performance of cognitive abilities. Thus, the accuracy and evaluation of LOTCA test supports its use as diagnostic tool for cognitive function as previously reported .
Moreover, significant positive correlation was obtained between the older subjects in the motor praxis, vasomotor organization, thinking operations, attention and concentration domains of the LOTCA –scores and their performance of functional physical activity. The data matched with others who suggested the strongest indication of physical exercise benefits on cognition function via enhancing academic performance, psychological and well-being [61–62].
Similarly, our study was in accordance with recent studies that reported improving in cognitive performance on a working memory task among younger and older adults following moderate intensity cycling . In addition, our study supported that positive effects of physical exercise intervention relay in enhancing psychological well-being, cognitive functioning and quality-of-life especially in older subjects with mild cognitive impairment as reported recently in literature [64–65].
In present study, there was slight in significant change in cognitive abilities scores and lipid profile related markers among non exercised control group. This change may be due to low-intensity physical activity such as routine day time life which accounts for most activity energy expenditure (AEE) in people who do not regularly exercise , these activities may useful in health outcomes such as cognitive impairment. This indicated with other research work who reported that older women identified a positive association between cognitive performance and total daytime movement, which suggests that total activity may be important for cognitive outcomes . Cognitive impairment and other metabolic disorders like CVD and stroke are significantly interrelated in older subjects with dyslipidemia [16, 68–69]. However, lipid-lowering therapies have demonstrated benefits in stroke prevention and prognosis [18, 57, 69, 70].
Lipid profile and lipoprotein (a) makers; choelestrol, TG, HDL-C, LDL-C, and Lipo (a) were estimated in this study. Paired t-test and student t-test analysis showed that participants with cognitive impairments had abnormal basal levels of lipids and lipoprotein (a) makers. The data matched with many studies that reported significant relationship between abnormal lipid profiles and a negative impact on cognition in old age [71–74].
Also, in this study, there was significant association between physical activity and cognitive impairment as measured by LOTCA scores. In physically active participants, there was significant reduction in the levels of TG, LDL-C, and Lipo (a), along with increase in the level of HDL-C and LOTCA scores with overall cognitive improvements status following 24 week of moderate aerobic training. The data were in line with many studies that performed the positive effects of physical exercise as anti-dyslipidemdic modulates via significant reduction in the levels of in circulating lipids and apolipoproteins (apos) induced by regular physical exercise [75–77]. Thus, the incorporation of exercise as non-drug modulates in subjects with abnormal lipid profiles has the priority among many clinical trials [78–79]. The association between biological and cognitive aging among older ages greatly supported by the presence of dynamic link between physical activity and cognitive functioning via changes in biological fluids related to cognitive domains [80–82].
In the present study, cognitive parameters correlated negatively with the reduction in the levels of TG, LDL-C, and lipo (a) and positively with the increase in the levels HDL-C and aerobic fitness as measured by VO2 max. The data were in consistence with other studies that reported the potential positive link of many physiological mediators including lipid profiles and aerobic fitness as potential mediators in physical activity-cognition relationships , and that the improved cognition significantly correlated with the increase in aerobic fitness and reduction in the levels of lipid profile [83–85].
Finally, the data obtained showed that physical activity status, aerobic fitness, and lipid profile played a pivotal role on cognitive performance of healthy older adults.
In conclusion, the data concluded that supervised moderate aerobic training for 24 weeks plays a positive significant effect in improving cognitive functions via modulating lipid profile and lipoprotein (a) of older adults.