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 Table of Contents  
ORIGINAL ARTICLE
Year : 2020  |  Volume : 14  |  Issue : 1  |  Page : 41-45

Relationship between physical activity and cognition among young adults


1 Assistant Professor (Ph. D Scholar, Gujarat University), Surat, Gujarat, India
2 Internee, Department of Physiotherapy, S. P. B. Physiotherapy College, Surat, Gujarat, India

Date of Submission27-Sep-2018
Date of Decision15-May-2019
Date of Acceptance07-Jan-2020
Date of Web Publication29-Jun-2020

Correspondence Address:
Dr. Salvi Shah
(Ph. D Scholar, Gujarat University), S. P. B. Physiotherapy College, Ugat-Bhesan Road, Surat - 395 005, Gujarat
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/PJIAP.PJIAP_43_18

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  Abstract 


BACKGROUND AND PURPOSE: Poor cognitive functioning is a predictor of mortality at all ages and as such can be seen as a marker of general health status. Leisure-time physical activity (PA) has been shown to have a beneficial impact on cognitive function. Existing research has focused on this association in children and the elderly. However, less is focused on young adults. Hence, the purpose of the present study was to find the relationship between PA and cognition among young adults.
METHODOLOGY: Two hundred individuals (18–24 years) were selected from different colleges of Surat city after obtaining permission from the college. All necessary instructions to perform cognition tests (Rey Verbal Auditory Learning Test, Stroop test, and Trail Making Test A and B) and to fill up the International PA Questionnaire were given to participants after obtaining the consent form. Spearman's correlation was used to analyze relationships between PA and cognition among participants.
RESULTS: Results showed a significant positive correlation (r = 0.53, 0.44, and 0.68) between PA and all the three cognitive measure tests (P < 0.05).
CONCLUSION: PA is an important factor in cognitive functioning among young adults. This finding of young adults suggests that PA may be beneficial to cognition during early and middle periods of the human life span and may continue to protect against age-related loss of cognitive function during older adulthood.

Keywords: Aging, International Physical Activity Questionnaire, physical activity, Rey Verbal Auditory Learning Test, Stroop test, Trail Making Test


How to cite this article:
Shah S, Shah S, Chauhan S. Relationship between physical activity and cognition among young adults. Physiother - J Indian Assoc Physiother 2020;14:41-5

How to cite this URL:
Shah S, Shah S, Chauhan S. Relationship between physical activity and cognition among young adults. Physiother - J Indian Assoc Physiother [serial online] 2020 [cited 2020 Jul 6];14:41-5. Available from: http://www.pjiap.org/text.asp?2020/14/1/41/288367




  Introduction Top


Regular physical activity (PA) is known to have numerous physical benefits. A physically active lifestyle is associated with a decreased risk of developing the most prevalent lifestyle diseases: coronary heart disease, stroke, obesity, type II diabetes and cancer (specific types). There is also evidence for enhanced cognitive function and a lower risk of cognitive decline and dementia. Despite these health benefits, physical inactivity has become a global problem.[1] Physical activity might play a central role in ameliorating age-associated cognitive losses.[2]

Cognition is a term that describes higher brain functions such as decision-making, calculating, problem solving, producing and using language and memory.[3] Cognition is the mental action or process of acquiring knowledge and understanding through thought, experience, and senses.[4] Superior cognitive function is key to maintaining a high quality of life as it helps individuals carry out day to day activities.[5]

Evidence suggests that physical activity may play a protective role in maintaining cognitive health among older adults, as measured by tests of neurophysiologic structure and function and traditional behavioral assessments of cognition.[6] Inverse relationships between cognitive decline and self-reported physical activity,[7],[8],[9],[10],[11],[12] as well as physical fitness[13] among older adults have been demonstrated in multiple studies. Similar relationships have been observed between physical activity and risk of dementia, vascular dementia, and AD(Alzheimer's disease).[14],[15] Intervention trials have shown improved cognitive function in response to physical fitness training,[16] and the association between physical activity and cognition seems to be most apparent with more complex cognitive processes.[17],[18],[19] There have been few studies, however, which have examined the relationship between PA and the ability to perform cognitively complex real-world activities.[3]

The existing literature examines the relationship between PA and cognitive function in elderly populations[20] with evidence of cognitive decline or in children[21] where the brain is still developing, whereas the effect of habitual PA on cognition in healthy, young to middle-aged adults has received limited attention. Public health guidelines recommend regular PA throughout life span.[22] Adequate PA in young to middle-aged adults may potentially have immediate benefits on cognitive function, resulting in a higher quality of life while potentially delaying age-related cognitive decline. This is important for a range of reasons including the fact that the majority of the population worldwide falls into this age bracket and, additionally, that life expectancy[23] and retirement age are predicted to increase.[24] If PA is shown to benefit cognition in healthy young to middle-aged adults, it would be advisable to foster adequate engagement before cognitive decline steepens through aging.[25] Hence, the purpose of the present study was to examine the relationship between PA and cognition among young adults.


  Methodology Top


Procedure

A comprehensive oral description of the nature, purpose, and procedure of the study was explained to the college authorities and principal in their vernacular language. After obtaining written and verbal permission from college authorities/principal, a cross-sectional survey was conducted on young adults (n = 200) aged between 18 and 24 years from different colleges of Surat city, Gujarat. Inclusion criteria for the study were individuals who are willing to participate in study, aged between 18 and 24 years, and able to read and write English language and exclusion criteria for the study were individuals with color blindness, with any known neurological condition, with any musculoskeletal problems in last months, and with any inability to follow test instructions. Written consent was obtained from the eligible participants before the commencement of the study. Information about demographic data and educational status were obtained from the participants. Anthropometric measurements such as weight, height, waist circumference, and hip circumference were taken. All necessary instructions to perform cognition tests and to fill up the International PA Questionnaire (IPAQ) were given to all the participants. Two hundred individuals aged between 18 and 24 years were selected from different colleges of Surat city after receiving permission from the college. Randomly individuals were selected from different classes of the selected college.

Measures

To measure cognition, rey verbal auditory learning test (RVALT), Stroop test, and Trail Making Test A and B were performed by all the participants in a randomized order. A therapist explained each test and demonstrated it in a standardized manner to measure cognition. After performing the tests, results were noted by the therapist. A stopwatch was used to measure time-based tests. RVALT was performed in the group and another two were performed individually in the sequence. Score of RVALT (No. of correct words), score of Stroop test (average of time for reading congruent color word list and incongruent color word list) and score for Trail Making Test (timing for completing part A and part B) in seconds were noted. The validity and reliability of all the three tests to measure cognition were good.[26],[27],[28]

The self-administered format for the long-version IPAQ in English was used to measure PA among the participants. The reliability and validity of this test are good.[29],[30] The long version IPAQ consists of 27 items that identify the frequency (times per week) and duration (minutes or hours per day) of PA performed in the activity domains of occupation (7 items); transportation (6 items); housework, house maintenance, and family care (6 items); recreation, sport, and leisure (6 items); and time spent sitting as an indicator of sedentary behavior (minutes or hours per day) in a weekday and in a weekend day (2 items). In the first four domains, the number of days per week and time per day spent in both moderate and vigorous activities are recorded. At work, during transportation and in leisure time, walking time is also included.[31] The time was used for sedentary activities, but it was not included in the calculation of the total PA score. The IPAQ incorporates a scoring mechanism, whereby each activity is assigned an intensity code expressed in terms of metabolic equivalents (METs). The MET is the ratio of metabolic rate during the activity as compared to the metabolic rate during rest. For each type of activity, the weighted MET minute per week is calculated as follows:[32][Table 1].
Table 1: Weighted MET minute per week for different type of activity

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One MET is equal to the energy expenditure during rest and is approximately equal to 3.5 ml O2/kg/min as the oxygen cost of activity[17] and 1 kcal/kg/h as the caloric equivalent for adults.[18] The methods used to score the long version IPAQ are presented in detail on the IPAQ website as well (www.ipaq.ki.se). The scoring protocol was followed for cleaning and truncation.[33] The total PA MET minute/week was then computed by summing the walking, moderate, and vigorous MET minute/week scores.[34]

Statistical analyses were done by SPSS 20 (IBM SPSS 20, trial version). Spearman's correlation was used to analyze the relationships between PA and cognition among the participants. Correlation was calculated and analyzed with the significance threshold set at P < 0.05.


  Results Top


A total number of 200 participants (112 females and 88 males) were included in the present study. The physical characteristics of all the participants are shown in [Table 2]. The mean value of three different cognitive tests for all the participants is shown in [Table 3]. The classification of PA among the participants has been shown in [Table 4]. The correlation between PA and cognition is shown in [Table 5]. Results of the present study showed that a positive correlation between PA and all three cognitive measures tests.
Table 2: Physical characteristics of participants

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Table 3: Mean value of cognitive tests

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Table 4: Classification of physical activity

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Table 5: Correlation between physical activity and cognition

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  Discussion Top


The study was aimed to find the relationship between PA and cognitive functions among young adults. Results of the study showed a positive correlation (P < 0.05) between PA and cognitive function (episodic memory and executive function).

Few studies reported a significant positive association between PA and executive function.[18],[35],[36],[37],[38],[39] Two studies noted nonsignificant, positive trends[40],[41] and four studies noted null result.[42],[43],[44],[45] One of the reviews suggested that episodic memory was found to be significantly positively associated with PA in two studies[40],[46] but not in another.[45]

A range of plausible biological mechanisms[47] may explain how PA influences cognitive functioning. These include structural changes to the central nervous system, neurotransmitter release, modulation of arousal levels, and enhanced cerebral capillary density/blood flow.[48] Exercise increases brain-derived neurotrophic factor (BDNF) and nerve growth factor which mediate short- and long-term enhancement of synaptic strength and reduce cell death in the hippocampus.[49] These neurotrophic, angiogenic, and neurogenic and synaptogenesis effects may play a role as both an enhancer and a protector of cognitive function and central nervous system integrity. The role of central (BDNF) and peripheral (estrogens, corticosteroids, growth hormone, and insulin-like growth factor-1) factors in mediation of the effects of physical exercise on brain functions has been promoted.[34] Further research is needed and should make the use of newer technologies in molecular biology and imaging to assist in studying the underpinning biological mechanisms. In addition to its role in health promotion, PA could also reduce the economic burden to society related to chronic degenerative diseases (e.g. hypertension, diabetes, and cardiovascular disease) that impair cognitive functioning.[39],[50] Evidence of a benefit of PA in the elderly provides evidence of neuroplasticity even in old age.[51] It is, therefore, plausible that PA might modify cognitive function in earlier adulthood and that these changes might enhance existing cognitive function or attenuates the decline with aging. Recent reviews indicate that high cardiovascular fitness may be particularly beneficial for brain volume in prefrontal regions,[52],[53] consistent with the selective effects of chronic exercise on executive function shown in recent studies.[35],[39],[43]

There are certain limitations to the study. The sample size of the study was relatively small, thus limiting statistical power and the generalizability of the results. The study used a cross-sectional design, and therefore, the performance effects attributed to variable amounts of PA may be due to other factors. Another limitation is the use of self-reported measures of PA rather than objective measures of activity (e.g., pedometer or accelerometer) and fitness (e.g., VO2). Hence, the longitudinal study with large sample size along with objective measurement of PA can be done. A future research with consideration of examining the differential effects on cognition of moderate versus vigorous physical activity, as well as the amount of physical activity along with the use of brain imaging techniques in conjunction with cognitive tests can be done.


  Conclusion Top


Results of the study showed that PA has an important role in cognitive functioning among young adults. This finding of young adults suggests that PA may be beneficial to cognition during early and middle periods of the human life span and may continue to protect against age-related loss of cognitive function during older adulthood. The results indicate that regular PA has a beneficial effect on the cognitive processes on executive function in young adults.

Acknowledgment

The authors would like to thank all the participants as well as principals of the college for their kind cooperation and giving permission to collect data from their colleges.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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