when the baby boomer generation began to retire , they became a topic of interest in south 
 korea . as the retired population of south korea ages , the older adults population continues 
 to increase faster than in any other country1 . as people age , their activity engagement may decrease or 
 change . continued activity engagement has showed positive effects on healthy life , mental health 
 and quality of life . the group based activities in community centres have been associated 
 with improvements in the health and well being of adults who have previously experienced 
 poor health and other forms of social disadvantage2 . continued work involvement or volunteerism provides opportunities 
 for social interaction and engagement , and may be associated with enhanced mental well - being 
 of older adults3 . increases in physical 
 activity has been associated with higher physical self - worth and fewer disability 
 limitations which have been associated with greater life satisfaction4 . for aging and activity engagement studies to be successful , the assessment tool must cover 
 a lot of activities . ideally , health is a state of adequate physical and mental independence 
 in activities of daily living5 . in 
 addition , voluntary work , cultural activities , holiday , sports , reading books , hobbies and 
 shopping are found to be successful predictors of the social connectedness of older 
 people6 . the activity card sort ( acs ) is a standardized assessment tool that evaluates the amount 
 and level of involvement in various activities7 . the acs consists of labeled photographs of older people 
 participating in a range of activities and has multiple benefits over existing measures of 
 participation of older adults , including ease of use , lack of dependency on literacy levels , 
 and the inclusion of a broad range of culturally relevant activities8 , 9 . originally 
 developed in the usa , the acs now has versions designed for use in israel , hong kong , 
 australia , and south korea10,11,12 . the present study aimed to gain and understanding of activity engagement of aging retirees . k - acs data was analysed to examine the effect of aging on activity engagement . data were collected by seven senior university students , who had completed four months of 
 clinical practice and were trained to administer and score the k - acs . eligible participants were individuals over 55  years old who could write and communicate in 
 korean . candidates were excluded if they had obvious auditory , visual , or cognitive 
 impairments8 . the study methods and procedures 
 were approved by the institutional review board of soonchunhyang university . the k - acs has three versions : institutional , recovery , and community living . the community living version requires participants to 
 sort 67 photographs of activities ( 33 photographs illustrating instrumental activities , 
 activities to support daily life within the home and community ; 18 photographs illustrating 
 leisure activities , nonobligatory activities that is intrinsically motivated and engaged in 
 during discretionary time ; and 16 photographs illustrating social activities , activities 
 that are characteristic and expected of an individual in a given position within a social 
 system ) into 5 categories : never done ,   given up ,   do now ,   do less ,  or  new activity . the retained level of activity engagement ( % ) is calculated as follows : level of current activity = values of  do now level of previous activity = values of  done previously  column ( i.e. ,  do now ,  do less  
 and  given up  ) retained level of activity ( by percentage ) = level of current activity / level of previous 
 activity  100% data were analyzed using spss version 20.0 . participants were divided into three age groups : 75  years 
 ( group a ) , 6574  years ( group b ) , and 5564  years ( group c ) . a one - way anova was used to 
 compare the mean retained level of activity ( mra ) among the three age groups , and scheff s 
 test was used for post - hoc analyses . the independent t - tests was used to 
 examine the significance of gender differences . 95% ci was used and the ` results were 
 accepted as significant if p<0.05 . participants were 
 assigned to the a , b , or c groups to compare the mean levels of activity retained with age . most participants had completed elementary school ( 85.75% ) and lived in urban communities 
 ( 72.28% ) . participants rated their health status on a five - point scale , ranging from 
  excellent  to  poor . the same scale was also used to rate each participant s difficulty 
 with activities of daily living , from  not at all  to  somewhat . most participants reported 
 living with a spouse ( 73.06% ) ( table 
 1table 1 . general characteristics of the participants ( n=386)numberpercent ( % ) sexmale19049.2female19650.8age556412532.4657413033.775 13133.9highest educationno education5514.2elementary school9524.6middle school8221.2high school11830.6college112.8university205.2graduate school51.3residenceurban27972.3rural10727.7self - rated healthexcellent287.3good13234.2average14738.1poor7920.5self - rated activities of daily living difficultynot at all6015.5not very14337.1neutral9324.1somewhat9023.3living arrangementwith spouse28273.1without spouse10426.9 ) . the comparison of the mean retained level of activities by agetotala(n=131)b(n=130)c(n=125)instrumental activities68.1 20.681.516.586.616.0**leisure activities71.420.683.219.584.418.3**social activities66.1  26.382.3  23.384.1  20.0 * * :  75  years old , : 6574  years old , : 
 5564  years old , * * : < 0.01 compared within activities ) . there were significant differences in the mra between group a and the other 
 age groups ( instrumental activities , f=36.81 , p<0.01 : leisure activities , f=17.71 , 
 p<0.01 , social activities , f=23.24 , p<0.01 ) , but no significant differences were found 
 between groups b and c ( table 3table 3 . the comparison of the mean retained level of activities by age and sexageabcinstrumental activitiesmale66.123.677.017.790.112.1(n=41)(n=77)(n=72)female69.019.282.514.681.819.2(n=90)(n=53)(n=53)leisure activitiesmale69.220.785.518.288.513.4(n=41)(n=77)(n=72)female72.320.779.820.979.022.4(n=90)(n=53)(n=53)social activitiesmale67.723.882.123.181.222.4 ( n=41 ) ( n=77 ) ( n=72)female65.427.582.623.779.022.4(n=90)(n=53)(n=53 ) :  75  years old , : 6574  years old , : 
 5564  years old . * * : < 0.01 compared within activities , : < 0.01 
 compared between male and female ) . when participants were divided by gender , the same results were obtained 
 except for the instrumental activities of males and the leisure activities in females . there 
 were significant differences in mra of instrumental activities between group b and c for 
 males , but there were no age differences in females of leisure activities . the independent 
 t - tests demonstrated significant gender differences of the mra in group c 
 ( table 3 ) . :  75  years old , : 6574  years old , : 
 5564  years old , * * : < 0.01 compared within activities :  75  years old , : 6574  years old , : 
 5564  years old . * * : < 0.01 compared within activities , : < 0.01 
 compared between male and female activity engagement is a natural means of maintaining physical and mental function , and 
 experiencing well being10 . however , 
 activity limitation is a frequent geriatric issue with considerable individual and societal 
 impacts . people living with activity limitations may be less likely to experience happiness 
 or life satisfaction , which can have a negative effect on their quality of life13 . however , little is known about the age 
 profile of activity engagement in the south korean retiree population with age . this study found that activity engagement decreased with age14 . examining the results of each age group , the most significant 
 changes appeared mainly in group a. this finding highlights the need for care for older 
 adults over 75  years to maintain their mra . it is important to recognize that when activity 
 participation is changing , there may be health issues that make older adults vulnerable to 
 functional decline15 . in contrast , 
 engagement in activity acts as a buffer against physical decline in later life16 , 17 . it is important to know that engagement in activity provides a 
 health benefit that is as important as physical exercise18 . in addition , the decreased engagement with age of males in instrumental activities , 
 continued engagement of females in leisure activities , and significant gender differences in 
 mra in group c , suggest the importance of age- , gender- and activity - specific analyses in 
 order to identify patterns of engagement . activity choices are affected by changes of life roles because of family dynamics , changes 
 in living situation , and the deaths of family and friends19 . all participants were volunteers ; thus , our 
 sample may not be representative of the entire post - retirement aging population . second , the 
 k - acs is a self - report measure , so it may not accurately reflect actual engagement . in 
 addition , the k - acs measures the numbers of activities , but does not measure the intensity , 
 frequency , or duration of each activity20 . finally , when calculating the retained level of activity , engagement 
 in new activities was not included in the analyses to identify decreases from previous 
 levels of activity . therefore , the mean level of current activity could be higher if new 
 activities were included in the calculations performed using the original equation .
[ purpose ] the purpose of this study was to analyze the activity engagement of the 
 retiree population in south korea . 
 [ methods ] the korean - activity card sort ( k - acs ) was 
 used to collect research data . a one - way anova and 
 post - hoc comparisons showed significant 
 group effects among three age groups . 
 the independent t - tests was used to analyze the 
 differences in mean retained level of activity ( mra ) between men and women . 
 [ results ] the 
 one - way anova showed statistically significant differences in mra among different age 
 groups . 
 scheff s test revealed a statistically significant decrease in mra in group a , 
 aged more than 75  years , as compared to the other two age groups . 
 when participants were 
 divided by gender , mra of instrumental activities showed a statistically significant 
 difference between the 6574 years group and the 5565 years group , but no difference in 
 females of the leisure activities among the age groups . 
 the independent t - tests 
 demonstrated significant gender differences in mra of activity of the 5564 years group . 
 [ conclusion ] these findings suggest that health professionals should monitor the changes 
 in retained level of activity after age 75 , to maintain their engagement , and the 
 importance of age- , gender- and activity - specific analyses in order to identifying 
 patterns of activity engagement .