physical inactivity is a risk factor for cardiovascular disease1 , diabetes2 , 3 , cancer4 , 5 , osteoporosis6 , cerebral infarction7 , 8 , and other 
 diseases , and is closely related to survival prognosis9 , 10 .
a large cohort study 
 ( japan public health center - based prospective study ) of about 80,000 subjects in japan found 
 that physical activity ( pa ) associated with the mortality rates of cancer , heart disease , 
 and cerebrovascular disease11 . a report 
 by the world health organization ranked physical inactivity as fourth among the global risk 
 factors for mortality , after hypertension , smoking , and hyperglycemia12 , whereas a japanese study ranked it third after smoking 
 and hypertension13 .
we previously 
 surveyed and studied the influence of daily pa on the physical functions and prognoses of 
 patients with cardiovascular disease .
we observed reduced physical functions and higher 
 rates of recurrence and re - hospitalization among patients with low pa levels for all 
 diseases14,15,16 . as decreased pa can 
 reduce physical functions and increase disease - specific mortality , we believe that 
 maintaining high levels of pa is extremely important from the standpoints of disease 
 prevention and survival prognosis .
health japan 21  program of the japanese ministry of health , labor , and welfare aims 
 to extend healthy life expectancies by supporting health promotion programs for the general 
 public .
increasing pa is an important part of health japan 21 , which encourages elderly 
 people ( age 70  years and older ) to increase their pa by 1,300 steps per day ( about 15  min , 
 650800 m)13 .
it is expected that 
 increased pa will improve physical functions ( muscle strength , balance ability ) , body 
 composition ( reduce body weight and fat mass , increase muscle mass ) , cardiovascular 
 functions ( reduce blood pressure and degree of arteriosclerosis ) , and quality of life ( qol ) , 
 and that maintaining a healthy lifestyle will produce a variety of physical and 
 psychological benefits , such as increased self - efficacy .
however , health japan 21 does not 
 state a specific target duration by which increasing pa by 1,300 steps per day can be 
 expected to have physical and psychological effects on healthy elderly people , nor did it 
 specify what the expected effects are .
thus , it is important to show the chronological and 
 quantitative effects of increasing pa by 1,300 steps / day .
the objective of this study was to clarify the effects of increased pa during 6 months on 
 physical functions , body composition , cardiovascular functions , health - related qol ( hr - qol ) , 
 and self - efficacy in community - dwelling elderly people .
the subjects were categorized into 2 
 groups based on whether they had met a pa target .
the effects were monitored at 3 and 6 
 months to clarify the physical and psychological changes in the subjects , quantitatively and 
 chronologically . for this study ,
the subjects were elderly people ( at least 65  years old but younger than 85  years old ) who 
 resided in port island in the chuo ward of kobe city in hyogo prefecture , japan . through 
 announcements in our university s homepage , newspapers , and community bulletin boards in may 
 and june 2014 , we sought participants for a project aimed at increasing pa and for this 
 study .
the applicants were invited to a lecture on pa ( covering the relationship between pa 
 and disease incidence , effects of higher pa , and specific methods of increasing pa ) and an 
 explanatory meeting about this study .
sixty - nine subjects agreed to participate in the 
 project and the study , and provided their consent in writing .
we excluded subjects with 
 cerebrovascular disease , orthopedic disease , respiratory organ disease , heart disease , or 
 other underlying disease that limited their level of pa ; those for whom increased pa was 
 deemed not beneficial ; and those who could not walk independently outdoors .
furthermore , all 
 subjects underwent cognitive function screening in the form of the rapid dementia screening 
 test17 , to confirm that they do not 
 have reduced cognitive function ( 7 points or lower ) .
this study was conducted with the 
 approval of the ethics committee of the hyogo university of health sciences ( no .
22 were excluded because they could not undergo the regular evaluations 
 for some reason , leaving 47 subjects for the analysis .
the mean age of the subjects was 
 71.9  years ( 6582  years ) ; there were 12 men and 35 women ; their mean body mass index ( bmi ) 
 was 22.4  kg / m ( 16.529.2  kg / m ) ; and their mean preintervention pa 
 was 9110 steps ( 3,56919,800 steps ) .
the subjects were categorized into 2 groups : those who 
 had achieved the pa target ( achievement group=18 subjects ) and those who did not achieve the 
 target ( non - achievement group=29 subjects ) .
pa monitors ( mediwalk mt - kt-2dz , terumo corp . ) had been distributed to the subjects ; these 
 had been used to measure pa for 7 continuous days before the intervention .
the subjects were given a 
 full explanation on how to use the pa monitors .
they were instructed to wear them on their 
 waists at all times , except during sleeping and bathing , to measure their total daily pa . 

the mean pa was calculated during 7 days in late june and early july 2014 .
the weather 
 during this period was clear or cloudy , with an average temperature of 23.7  c .
the pa 
 target ( mean pa + 1,300 steps ) was set based on the mean preintervention pa , and the 
 subjects were instructed to increase their pa by using this target as a standard .
they were 
 also instructed to record the total pa for each day on a special form , before sleeping .
the 
 pa monitors and pa records were collected at 3 and 6 months after the start of the 
 intervention .
data on the pa monitors were transferred to a computer , and the total pa per 
 day was calculated by using a special software ( smile data vision , terumo corp . ) .
subjects 
 whose mean pa after 6 months reached the target level were placed in the achievement group , 
 whereas those who did not reach the target were placed in the non - achievement group . the 
 body composition ,
vascular functions , physical functions , hr - qol , and self - efficacy were 
 compared between the groups .
each item was measured before the intervention , after 3 months , 
 and after 6 months .
body fat percentage , muscle mass , muscle mass percentage , basal metabolic rate , and 
 estimated bone mass were measured with the bioelectric impedance method by using a 
 high - precision body composition monitor ( df860 , yamato - scale ) .
the subjects were asked to avoid excessive eating and drinking the 
 day before , and to refrain from eating or drinking for 2  h before the measurements . an abi / pwv device ( bp-203rpeiii form , omron co. )
was used to measure the brachial - ankle 
 pulse wave velocity ( bapwv ) and ankle - brachial index ( abi ) .
measurements were taken after 
 the subjects had rested while lying on a bed for 5  min .
two measurements of each variable 
 were taken , and the mean values were used .
the grip strength of the dominant hand was measured with a grip meter ( hand grip meter 
 6103 , tanita corp . ) in the standing position .
the knee - extension strength of the dominant leg was measured with a handheld 
 dynamometer ( hhd ) ( mutas f-1 , anima corp . ) in a sitting position .
two measurements ( with at 
 least 30  s rest between them ) were taken after the subjects practiced the procedure , and the 
 maximum value was used .
the arm length was measured as the distance from the center of the 
 knee joint to the middle of the hhd sensor .
torque ( nm ) was calculated by multiplying the 
 force applied to the sensor ( n ) by the arm length ( m ) , which was then divided by the 
 subject s body weight ( kg ) to obtain the torque - to - weight ratio ( nm / kg ) .
balance ability was measured as the time the subjects could stand on the dominant leg .
two 
 measurements were taken by using a stopwatch , and the maximum value was used .
the maximum 
 one - leg standing time was set at 120 s. if a subject could stand on one leg for 120  s , the 
 test was stopped at that point .
walking ability was evaluated on a 15-m walking path in a 
 hallway with no obstructions .
a stopwatch was used to measure the time it took the subjects 
 to walk 10  m at a comfortable pace and at maximum speed . for comfortable
walking , the 
 subjects were instructed to walk at their normal speed in daily life . for maximum walking , 
 they were instructed to walk as fast as they could without running .
the walking speed was 
 calculated as 10  m  60  s  walking time .
hr - qol was measured by using the standard version of the mos 36-item short - form health 
 survey ( sf-36v2 ) in a self - administered format .
the points for each item were calculated on 
 a sf-36v2 scoring program ( ihope international ) .
the pa self - efficacy scale of oka et al . 
 was used to evaluate self - efficacy18 . 

five grades of activity stress ( intensity , time , number of times ) were set for walking 
 activity .
the subjects self - recorded their current degree of walking , and the mean values 
 were calculated .
the achievement group and the non - achievement group were compared by using a t - test and the 
  test .
comparisons between baseline , 3 months , and 6 months were performed 
 with one - way analysis of variance ( bonferroni method ) .
the significance level was set at 
 < 5% . as a sub - analysis ,
correlation coefficients were calculated between the pa rate of 
 change and the rates of change of the other items .
rates of change were calculated as ( 6 
 months  baseline ) / baseline  100 .
table 1table 1.baseline characteristics of the study participants ( n=47)variablestotal(n=47)achievement group ( n=18)non- achievement group(n=29)age ( years)71.9  4.271.9  4.571.8  3.9gender ( male / female)12 / 35 6 / 1214 / 35high ( cm)156.1  9.9155.9  9.7156.2  9.8weight ( kg)54.9  9.954.3  8.555.3  10.6bmi ( kg / m)22.4  2.722.2  2.422.4  2.9hypertension ( % ) 29.838.924.1hyperlipidemia ( % ) 19.133.310.3diabetes ( % ) 10.611.110.3musculoskeletal disorders ( % ) 29.827.831.1baseline pa ( steps / day)9,110  3,2408,270  2,5919,631  3,431data are mean  standard deviation or % .
p values were calculated using an unpaired t test for the continuous variables or a 
  test for the categorical variables shows the baseline characteristics of all the subjects , the achievement group , 
 and the non - achievement group ( table 1 ) .
no 
 significant differences were observed between the groups in age , gender , height , weight , 
 bmi , hypertension , hyperlipidemia , diabetes , musculoskeletal disorders , or preintervention 
 pa .
p values were calculated using an unpaired t test for the continuous variables or a 
  test for the categorical variables table 2table 2.comparison of physical activity , body composition , vascular functions , and 
 physical functions between the achievement group and non - achievement groupachievement group ( n=18)non- achievement group ( n=29)baseline3 month6 monthbaseline3 month6 monthphysical activity ( steps / day)8,270  2,59110,496  2,729 * 9,631  3,4318,501
 2,910**body compositionbody fat ( % ) 28.9  9.229.1  9.629.0 8.831.3  7.331.3  7.431.8  7.7muscle mass ( kg)15.1  3.414.8  3.215.2  3.315.0  3.814.9  3.715.1  4.1muscle rate ( % ) 27.9  3.927.5  4.128.0  3.926.7  3.926.9  3.127.5  3.6estimated bone quantity ( kg)1.8  0.41.8  0.41.8  1.91.8  0.41.8  0.41.8  0.5vascular functionbapwv ( cm / s)1,769.3  273.31,769.0  360.81,739.0  318.21,815.0  310.91,810.5  320.91,827.5  308.1abi1.2  0.11.2  0.11.2  0.11.2  0.11.2  0.11.2  0.1body functionhand grip ( kg)25.9  5.825.6  5.626.2  6.625.2  6.925.0  6.224.7  7.3knee extension strength ( nm / kg)28.3  11.730.3  10.430.3  13.927.2  9.627.1  9.927.4  9.3one leg standing time ( sec)77.3  44.084.9  40.979.9  38.256.5  39.766.8  45.468.8  44.8comfortable walking speed ( m / min)88.6  8.790.5  10.990.4  10.287.2  13.887.7 
13.589.8  11.6maximal walking speed ( m / min)118.6  15.9121.6  18.1119.3  14.7114.9  14.2115.4  14.3112.6  15.4bapwv : brachial - ankle pulse wave velocity ( reflecting degree of vascular stiffness ) ; 
 abi : ankle brachial index . * vs. achievement group baseline , p<0.01 ,
achievement group 6 month , p<0.05 shows the changes in pa , body composition , vascular functions , and physical 
 functions in the achievement and non - achievement groups at baseline , after 3 months , and 
 after 6 months ( table 2 ) .
while baseline pa was 
 not significantly different between the groups , pa in the achievement group increased 
 significantly after 6 months and decreased significantly in the non - achievement group . 

moreover , pa was significantly lower in the non - achievement group than in the achievement 
 group after 6 months . for body composition
, no significant changes were observed between the 
 groups in body fat percentage , muscle mass , muscle mass percentage , basal metabolic rate , or 
 estimated bone mass at baseline , after 3 months , or after 6 months . for vascular functions
, 
 no significant differences were observed between the groups in bapwv or abi at baseline , 
 after 3 months , or after 6 months . for physical functions ,
no significant differences were 
 observed between the groups in hand - grip strength , knee - extension strength , one - leg standing 
 time , comfortable walking speed , or maximum walking speed at baseline , after 3 months , or 
 after 6 months .
bapwv : brachial - ankle pulse wave velocity ( reflecting degree of vascular stiffness ) ; 
 abi : ankle brachial index . * vs. achievement group baseline , p<0.01 , * * vs .
achievement group 6 month , p<0.05 table 3table 3.comparison of hr - qol and self - efficacy between the achievement group and 
 non - achievement groupachievement group ( n=18)non - achievement group ( n=29)baseline3 month6 monthbaseline3 month6 monthsf-36physical functioning89.4  6.690.6  7.090.7  8.090.4  7.688.5  11.789.7  9.9role functioning87.8  19.092.4  12.994.3  9.8 92.4  11.682.5  17.3 83.2  23.6 pain82.2  18.483.9  22.078.2  21.780.3  16.277.2  20.285.0  12.2vitality70.8  15.270.5  12.571.2  13.477.5  13.572.0  14.979.3  13.4social functioning88.9  17.691.7  13.895.8  8.390.4  16.085.6  16.586.5  19.6emotional functioning88.4  18.089.8  14.697.2  6.2 86.2  17.785.9  17.687.2  21.1mental health79.7  14.081.1  13.980.6  13.878.6  15.779.1  12.884.2  11.0self efficacygait93.8  12.395.6  7.994.5  8.886.4  16.685.4  17.391.4
non - achievement group baseline , p<0.01 shows the changes in hr - qol and self - efficacy in the achievement and 
 non - achievement groups at baseline , after 3 months , and after 6 months ( table 3 ) . in the achievement group , role functioning ( p<0.05 ) 
 and emotional functioning ( p<0.01 )
increased significantly after 6 months compared with 
 baseline . in the non - achievement group , role functioning ( p<0.01 ) decreased significantly 
 after 3 and 6 months compared with baseline .
no significant difference in self - efficacy was 
 observed between the groups . * vs. achievement group baseline , p<0.05 .
non - achievement group baseline , p<0.01 calculating correlation coefficients between the pa rate of change and the rates of change 
 of the other items did not show significant correlations with the rates of change of body 
 composition , vascular function , body function , or self - efficacy .
however , significant 
 correlations were observed with the rates of change of role functioning ( r=0.41 , p<0.01 ) , 
 social functioning ( r=0.34 , p<0.05 ) , and emotional functioning ( r=0.32 , p<0.05 ) .
of the 69 subjects , 18 ( 26.1% ) achieved the pa target . although no significant differences 
 between the achievement and non - achievement groups were observed in age , gender , bmi , or 
 concomitant disease , the subjects in the achievement group walked about 1,500 steps more 
 than their baseline pa , which means they added a certain amount of exercise in their daily 
 lives .
moreover , the baseline number of steps in both groups was higher than that of the 
 average elderly japanese person ( males 5,436 , females 4,604)13 , which suggests that many of the people who were interested in this 
 study had a high degree of health awareness .
no significant differences in the body composition items were observed between baseline and 
 after 3 or 6 months . a randomized controlled trial ( rct ) with 182 subjects conducted by 
 slentz et al . reported strong correlations between pa and body fat mass , lean body mass , and 
 waist circumference19 . the pa level used 
 in their rct differed from that of the present study ; however , the length of the 
 intervention was roughly the same .
however , the subjects of the rct were generally 
 overweight , with bmi from 25 to 35  kg / m and mean body fat percentage of about 
 35% , whereas the mean bmi and mean fat percentage of our subjects were 22.4  kg / m 
 and 30% , respectively . thus , most of the subjects in the present study had standard 
 physiques .
this indicates that increased pa during a short period of about 6 months can 
 improve body composition in obese subjects ; however , when the subjects have a standard 
 physique , there is almost no impact on body composition .
furthermore , nakae et al . reported 
 that subjects who took at least 1,000 more steps per day for 1  year after receiving support 
 for increasing their pa had significantly lower body weight , fat percentage , and bmi20 .
the age , bmi , and fat percentage of the 
 subjects in their study were similar to those in our study . to improve body composition in 
 subjects with standard physiques
, pa may need to be increased for at least 6 months . neither group exhibited significant differences in vascular functions after 3 or 6 months . 

the bapwv reflects the degree of vascular stiffness , with higher values indicating higher 
 stiffness21 .
previous studies have 
 found links between daily pa and bapwv22 , 23 ; however , the effects of interventions 
 that increase pa on the bapwv have yet to be established .
as the bapwv is affected by 
 vascular stiffness , we hypothesized that increased pa would improve the bapwv ; however , our 
 results did not show an impact on vascular stiffness .
this may be because the bapwv values 
 of the subjects were within the normal range , or because of the short 6-month duration of 
 the intervention .
for physical functions , no significant differences were observed in balance ability or 
 walking ability .
the knee - extension strength , balance ability , and walking ability mainly 
 reflect lower - limb functions , and previous studies have reported a link between pa and 
 lower - limb function24 , 25 .
however , takahashi et al . reported that elderly persons 
 who engaged in 30  min of walking per day , 5 days per week , for 12 weeks did not exhibit 
 significant differences in the cross - sectional area of lower - limb muscles26 .
they concluded that walking alone can not 
 increase muscle mass  a finding supported by the present study .
it seems to be difficult to 
 improve lower - limb functions by increasing pa by 1,300 steps per day for a short period of 6 
 months . for hr - qol ,
the achievement group showed significantly higher scores on role functioning 
 after 6 months compared with baseline , whereas the scores in the non - achievement group 
 decreased significantly after 3 and 6 months .
it has been previously reported that 
 maintaining or increasing pa contributes to maintaining or improving hr - qol27a finding supported by the present study . 
 we surmise that obtaining sufficient exercise by increasing pa has positive mental and 
 psychological effects that lead to increased hr - qol . in contrast
, role functioning decreased 
 significantly after 3 months and 6 months in the non - achievement group , and pa also declined 
 significantly at these time points .
a significant correlation was also observed between the 
 pa rate of change and the rate of change of role functioning , which indicates an association 
 between pa and role functioning even over a short period of 6 months .
the limitations of this study were that many of the subjects had relatively high levels of 
 pa and a high degree of health awareness .
therefore , the subjects levels of psychological 
 and physical functions may have differed from a random sample of community - dwelling elderly 
 people . however , many health - related initiatives for community - dwelling elderly people 
 attempt to increase pa , such as that in this study .
we thus believe that our results would 
 be relevant to future initiatives for increasing pa in community - dwelling elderly people . in 
 the future , it will be important to accurately assess the effects of increased pa on 
 physical functions , body composition , vascular functions , and mental / psychological areas 
 through large studies on increasing pa in community - dwelling elderly people .
 [ purpose ] the objective of this study was to clarify the effects of increased number of 
 steps on body composition , physical functions , vascular functions , health - related quality 
 of life ( hr - qol ) and self - efficacy in elderly people . [ subjects and methods ] the subjects 
 were 47 elderly persons who resided in port island in the chuo ward of kobe city in hyogo 
 prefecture , japan . 
 after the calculation of the mean preintervention physical activity 
 ( pa ) , the subjects were instructed to increase their pa to a target baseline + 1,300 
 steps / day . 
 body composition , physical functions , vascular functions , hr - qol , and 
 self - efficacy were measured at baseline , after 3 and 6 months . 
 these items were compared 
 between a group that increased their pa and a group that did not . [ results ] after 6 
 months , 26.1% of the subjects achieved the pa target . 
 no significant improvements were 
 observed in body composition , physical functions , vascular functions , or self - efficacy for 
 either group after 3 and 6 months . 
 however , the hr - qol improved significantly after 6 
 months in the achievement group . 
 [ conclusion ] although the intervention to increase pa did 
 not produce significant improvements after 6 months in body composition , physical 
 functions , vascular functions , or self - efficacy , the hr - qol improved significantly during 
 this relatively short period . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION