Exercising alone versus with others and associations with subjective health status in older Japanese: The JAGES Cohort Study

Abstract

Although exercising with others may have extra health benefits compared to exercising alone, few studies have examined the differences. We sought to examine whether the association of regular exercise to subjective health status differs according to whether people exercise alone and/or with others, adjusting for frequency of exercise. The study was based on the Japan Gerontological Evaluation Study (JAGES) Cohort Study data. Participants were 21,684 subjects aged 65 or older. Multivariable logistic regression models were used to examine the association. The adjusted odds ratios (ORs) for poor self-rated health were significantly lower for people who exercised compared to non-exercisers. In analyses restricted to regular exercisers the ORs for poor health were 0.69 (95% confidence intervals: 0.60–0.79) for individuals exercising alone more often than with others, 0.74 (0.64–0.84) for people who were equally likely to exercise alone as with others, 0.57 (0.43–0.75) for individuals exercising with others more frequently than alone, and 0.79 (0.64–0.97) for individuals only exercising with others compared to individuals only exercising alone. Although exercising alone and exercising with others both seem to have health benefits, increased frequency of exercise with others has important health benefits regardless of the total frequency of exercise.

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Scientific RepoRts | 6:39151 | DOI: 10.1038/srep39151
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Exercising alone versus with others
and associations with subjective
health status in older Japanese: The
JAGES Cohort Study
Satoru Kanamori1,2, Tomoko Takamiya1, Shigeru Inoue1, Yuko Kai3, Ichiro Kawachi4
& Katsunori Kondo5,6,7
Although exercising with others may have extra health benets compared to exercising alone, few
studies have examined the dierences. We sought to examine whether the association of regular
exercise to subjective health status diers according to whether people exercise alone and/or with
others, adjusting for frequency of exercise. The study was based on the Japan Gerontological Evaluation
Study (JAGES) Cohort Study data. Participants were 21,684 subjects aged 65 or older. Multivariable
logistic regression models were used to examine the association. The adjusted odds ratios (ORs) for
poor self-rated health were signicantly lower for people who exercised compared to non-exercisers.
In analyses restricted to regular exercisers the ORs for poor health were 0.69 (95% condence intervals:
0.60–0.79) for individuals exercising alone more often than with others, 0.74 (0.64–0.84) for people
who were equally likely to exercise alone as with others, 0.57 (0.43–0.75) for individuals exercising with
others more frequently than alone, and 0.79 (0.64–0.97) for individuals only exercising with others
compared to individuals only exercising alone. Although exercising alone and exercising with others
both seem to have health benets, increased frequency of exercise with others has important health
benets regardless of the total frequency of exercise.
Physical activity has been demonstrated to have various health benets1,2. e benets of physical activity apply
regardless of the context, i.e. whether it occurs as part of work, leisure, transport, or housework3. However, it
remains unclear whether exercise is more benecial for those exercising with others, compared to exercising
alone (e.g. on the basement treadmill).
is question has been previously discussed by distinguishing physical activity into exercising alone versus
with others4. e mechanisms for health benets from exercising with others may include not only physiological
eects through physical activity, but also psychological and social factors. A systematic review focusing on the
psychosocial benets of exercising with others revealed that working out with others may enhance social connect-
edness, social support, and peer bonding5. ese social relationships have been shown in turn to have potential
health benets6,7, and exercising with others may therefore have extra health benets compared to exercising
alone.
However, few studies have examined the dierences in health associations between exercising alone and exer-
cising with others. One study conducted on middle-aged Japanese adults showed that there was statistically no
dierence in the incidence of poor mental health ve years later between non-exercisers and those exercising
mostly alone, while the incidence was lower among those exercising mostly with exercising others, compared to
non-exercisers8. However, the study did not directly compare exercising alone and with others, and the analyses
1Department of Preventive Medicine and Public Health, Tokyo Medical University, Tokyo, Japan. 2Human Resource
Management Department, ITOCHU Techno-Solutions Corporation, Tokyo, Japan. 3Physical Fitness Research
Institute, Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan. 4Department of Social and Behavioral
Sciences, Harvard School of Public Health, Boston, Massachusetts, USA. 5Center for Preventive Medical Sciences,
Chiba University, Chiba, Japan. 6Center for Well-being and Society, Nihon Fukushi University, Aichi, Japan.
7Department of Gerontology and Evaluation Study, Center for Gerontology and Social Science, National Center for
Geriatrics and Gerontology, Obu city, Aichi, Japan. Correspondence and requests for materials should be addressed
to T.T. (email: takamiya@tokyo-med.ac.jp)
Received: 17 May 2016
Accepted: 18 November 2016
Published: 15 December 2016
OPEN

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did not adjust for dierences in the frequency of exercise. One cohort study examining older Japanese adults
showed a higher risk of incident functional disability (hazard ratio was 1.29 (95% condence intervals: 1.02–
1.64)) among those who did not participate in a sports organization compared to those who did, even though
both groups reported regular exercise9. A cross-sectional study in Australian adults showed that sports club par-
ticipants resulted in more positive benets for various aspects of quality of life than gymnasium participants
or walking participants10. ese studies suggest the possibility that exercising with others has additional health
eects over and above exercising alone. However, exercising alone and exercising with others were not directly
compared. We therefore sought to address this gap using cross-sectional data from a cohort of older Japanese
adults.
Self-rated health is one subjective indicator that reects overall health status. Self-rated health is commonly
used as a health outcome because of its established validity as a predictor of mortality, regardless of other medical,
behavioral, or psychosocial factors11. erefore, the aim of this study was to examine whether the association
of subjective health status to exercise diers according to exercising alone and/or with others, adjusting for fre-
quency of exercise. We hypothesized that there would be a lower prevalence of poor self-rated health among those
performing exercising with others compared to those only exercising alone, even aer adjusting for frequency
of exercise. Although the existing guideline on physical activity mentions intensity and duration3, it does not
mention whether exercise should be performed alone or with others. If exercising with others is shown to have
greater health benets than exercising alone, this would suggest the importance of including a social interaction
perspective in health promotion using physical activity.
Methods
Study sample. We used cross-sectional data from the baseline wave of the Japan Gerontological Evaluation
Study (JAGES), which is a population-based survey of community-dwelling seniors12. e JAGES sample includes
only those who did not already have functional disabilities at the baseline survey. ose without functional disa-
bilities were dened as those without eligibility for receiving long-term public care insurance benets. e cohort
was established in 2010 to examine prospectively the determinants of healthy aging in a sample of individuals
aged 65 years and older. Subjects were selected by random sampling in each municipality, using the residential
registry in each locality as the sampling frame. e present analysis was based on a sub-sample of the JAGES
cohort study as a national sample of 137,736 people in 30 municipalities across Japan (response rate: 71.1%).
Questionnaires were sent to 38,724 people and responses were received from 27,684 (response rate: 71.5%). We
excluded 6,000 respondents who did not respond to the questions on age, sex, self-rated health, frequency of exer-
cising alone and with others, or need of assistance in activities of daily living (ADL). e nal study population
consisted of 21,684 subjects. Subjects comprised 10,390 men (47.9%) and 11,294 women (52.1%), with a mean
age of 73.5 ± 6.0 years.
Measures. Subjective health status. Subjects were asked, “How is your current health status?” with possible
responses: excellent, good, fair, and poor. Dichotomisation of multinominal self-rated health is frequently used in
studies and has been validated13. Based on the previous study, subjects who responded with “fair,” or “poor,” were
combined to form our outcome variable. e test-retest reliability of self-rated health was shown to be good in a
variety of subgroups by age and sex14. In addition, the criterion-related validity of self-rated health was shown to
predict mortality in a review11, and similar results were also observed in older Japanese adults, regardless of age,
marital status, health behaviors, symptoms of depression, and chronic co-morbid conditions15.
Exercising alone and exercising with others. To dene exercising alone, respondents were asked, “How oen do
you exercise alone?” To dene exercising with others, respondents were asked, “How oen do you exercise with
a relative, friend, or acquaintance?” For each question, possible responses were: four or more times a week, two
or three times a week, once a week, one to three times a month, a few times a year, and none. Based on a previ-
ous study that examined the relationship between mortality and physical activity16, the frequency of exercising
alone and exercising with others was divided into six mutually exclusive categories: (1) non-exercisers, (2) people
who only exercised alone (Ea-only), (3) people who reported exercising more frequently alone than with others
(Ea > Ewo), (4) people who reported exercising alone or with others with equal frequency (Ea = Ewo), (5) people
who exercised with others more frequently than exercising alone (Ea < Ewo); and (6) people who only exercised
with others (Ewo-only) (Fig.1). Next, the total frequency of exercise (combinations of two variable categories)
Figure 1. Patterns of exercise. Ea-only: people who only exercised alone. Ea > Ewo: people who reported
exercising more frequently alone than with others. Ea = Ewo: people who reported exercising alone or with
others with equal frequency. Ea < Ewo: people who exercised with others more frequently than exercising alone.
Ewo-only: people who only exercised with others.

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was calculated and divided into six categories (see SupplementaryFig.S1). e higher the category, the greater the
frequency of exercise. e categories were dichotomized into two groups: categories 1 to 3 reected individuals
who exercised less than twice a week, categories 4 and 5 exercised more than twice a week.
Covariates. Based on previous studies9,17, age, sex, annual equivalized income (less than 2 million yen per
year = “low”, 2–3.99 million yen per year = “middle”, 4 million yen or more per year = “high”), educational
attainment (less than 10 years, more than 10 years), household composition (living alone, with others), occu-
pational status (employed, not employed), self-reported medical conditions (no illness or disability, illness or
disability), instrumental activities of daily living (IADL) (instrumental self-maintenance18; 5 points = “high”,
0–4 points = “low”), depressive symptoms (Geriatric Depression Scale19; 0–4 points = “no depression”, 5–9
points = “depressive tendency”, 10 points or more = “depression”), and total frequency of exercise were included
as covariates in our regression models. Furthermore, as exercising with others may reect sociability; frequency
of meeting friends (two or more times a week, once a month to once a week, less than once a month), receiving
instrumental support, providing instrumental support, receiving emotional support, and providing emotional
support (yes, no) were also included as covariates.
Statistical analysis. To examine whether the association of subjective health status to exercise diers
according to exercising alone and/or with others, we performed multivariable logistic regression to calculate the
odds ratios (ORs) for poor self-rated health. All variables were set as dummy variables. A “missing” category was
used in analysis to account for missing values in response to questions.
e dependent variable was self-rated health and independent variables were the six groups characterized by
frequency of exercising alone and exercising with others. In Model 1, age, sex, annual equivalized income, educa-
tional attainment, household composition, occupational status, self-reported medical conditions, IADL, depres-
sion, frequency of meeting friends, receiving instrumental support, providing instrumental support, receiving
emotional support, and providing emotional support were added as covariates to the univariate model. In Model
2, total frequency of exercise was added to Model 1. In addition, to perform sensitivity analysis for examining
whether the associations dier by total frequency of exercise, we conducted further analysis by stratifying the
analyses into categories 4 and 5 (those who exercise at least twice a week) versus categories 1 to 3 (those who
exercised less than twice a week).
SPSS 21.0 J was used for statistical analysis with a 2-tailed signicance level set at 5%.
Ethics statement. Ethical approval for the study was obtained from the Nihon Fukushi University Ethics
Committee (application number: 10–04) and Chiba University Ethics Committee (application number: 1777).
is study was performed in accordance with the principles of the Declaration of Helsinki. Informed consent was
obtained from all participants.
Results
Table1 shows characteristics of individuals according to their patterns of exercise. ose who exercised with oth-
ers (Ea > Ewo, Ea = Ewo, Ea < Ewo and Ewo-only) tended to be younger, and this group had a higher proportion
of people with a high equivalized income, high educational attainment, living with others, high IADL score, no
depression, rich social relationships, and good self-rated health. Among exercisers (Ea-only, Ea > Ewo, Ea = Ewo,
Ea < Ewo and Ewo-only), there was a higher proportion of people who exercised less than twice a week among
individuals who only exercised with others (Ewo-only).
Table2 shows the adjusted ORs for poor self-rated health according to patterns of exercise. In Model 1 for all
participants, the ORs for poor health were signicantly lower for individuals who exercised (regardless of whether
alone or with others; (Ea-only, Ea > Ewo, Ea = Ewo, Ea < Ewo and Ewo-only)). In the next set of models, we
excluded non-exercisers in order to draw comparisons just among the dierent types of people who performed
regular exercise. In these analyses, individuals who exercised alone (Ea-only) became the reference group for
all comparisons. In Model 1, the ORs were 0.67 (95% condence intervals: 0.58–0.77) for people who exercised
alone more oen than with others (Ea > Ewo), 0.72 (0.63–0.82) among people who exercised equally frequently
alone or with others (Ea = Ewo), 0.58 (0.44–0.76) for individuals who exercised more oen with others compared
to alone (Ea < Ewo), and 0.86 (0.70–1.05) for individuals who only exercised with others (Ewo-only). e cat-
egory of individuals who exclusively exercised with others (Ea > Ewo, Ea = Ewo, Ea < Ewo and Ewo-only) was
statistically indistinguishable from people who exercised alone (Ea-only). e covariates in Model 1 plus total
frequency of exercise were included in Model 2; the corresponding ORs were 0.69 (0.60–0.79), 0.74 (0.64–0.84),
0.57 (0.43–0.75), 0.79 (0.64–0.97).
Stratied analysis was then performed by dichotomizing the sample according to frequency of exercise. In
Model 2, the ORs for individuals only exercising with others (Ewo-only) were similar results of the analysis per-
formed on all exercisers, even though these were not statistically signicant in either stratum.
Discussion
is study was the rst to examine whether the association of subjective health status to exercise diers according
to exercising alone and/or with others, adjusting for frequency of exercise. As expected, in the analysis of all par-
ticipants, the ORs for poor self-rated health were signicantly lower for all exercise groups (Ea-only, Ea > Ewo,
Ea = Ewo, Ea < Ewo and Ewo-only) compared to non-exercisers. In the analysis excluding non-exercisers, the
ORs for poor self-rated health were signicantly lower for people who exercised both alone and with others
(Ea > Ewo, Ea = Ewo and Ea < Ewo) and people who only exercised with others (Ewo-only) compared to people
who only exercised alone (Ea-only), aer adjusting for total frequency of exercise. Moreover, although the ORs
were not signicantly lower for people who only exercised with others (Ewo-only), similar results were found

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Ea-only Ea > Ewo Ea = Ewo Ea < Ewo Ewo-only Non-exercisers
NMean ± SD 6,018 3,685 3,895 760 1,131 6,195
Age (years) 73.8 ± 6.1 72.6 ± 5.4 72.9 ± 5.4 72.3 ± 5.1 72.4 ± 5.5 74.5 ± 6.7
Sex (%) Males 48.8 53.4 46.9 44.1 36.5 47.1
Equivalized income (%)
Low 44.3 38.2 41.7 41.1 35.2 44.1
Middle 30.7 36.9 32.2 36.6 38.2 27.3
High 7.9 10.6 9.2 10.3 10.8 8.5
Missing 17.2 14.3 16.9 12.1 15.8 20.1
Educational attainment (%)
≤ 9 40.1 30.8 37.6 29.3 29.9 47.9
≥ 10 58.5 68.1 61.2 69.5 68.3 50.1
Missing 1.4 1.1 1.2 1.2 1.8 2.1
Household composition (%)
Living alone 16.8 12.0 11.1 11.2 11.4 13.6
With others 79.1 84.8 85.0 85.7 85.5 81.3
Missing 4.1 3.2 3.9 3.2 3.1 5.1
Occupational status (%)
Employed 22.2 20.8 22.2 17.4 22.9 26.1
Not employed 70.1 72.5 70.1 76.1 70.5 63.6
Missing 7.7 6.7 7.7 6.6 6.6 10.3
Self-reported medical condition (%)
No illness or disability 14.4 16.9 16.4 12.8 18.2 14.2
Illness or disability 81.3 78.3 77.8 80.5 75.2 80.4
Missing 4.3 4.8 5.8 6.7 6.6 5.4
IADL (%)
High 81.2 86.8 84.9 90.4 86.4 70.4
Low 16.6 11.8 13.1 7.6 11.9 26.4
Missing 2.2 1.4 2.1 2.0 1.7 3.2
Depression (%)
No depression 60.4 72.2 72.1 72.5 68.8 53.5
Depressive tendency 18.5 11.3 12.2 12.1 13.4 20.9
Depression 5.6 2.0 2.7 2.8 4.1 8.7
Missing 15.4 14.4 13.0 12.6 13.8 16.9
Frequency of meeting friends (%)
< 1/mo 31.9 16.1 16.3 13.8 16.9 35.6
1/mo-1/wk 35.4 38.7 29.4 29.7 33.6 31.6
≥ 2/wk 28.5 42.9 51.2 54.5 47.3 26.7
Missing 4.2 2.3 3.1 2.0 2.2 6.2
Receiving emotional support (%)
Ye s 91.3 95.7 95.7 97.1 95.8 89.3
No 6.8 2.7 2.9 1.8 2.9 7.9
Missing 1.9 1.6 1.4 1.1 1.3 2.8
Providing emotional support (%)
Ye s 89.3 94.7 94.2 95.9 94.3 85.1
No 7.6 3.0 3.5 2.1 3.7 10.6
Missing 3.0 2.4 2.2 2.0 1.9 4.2
Receiving instrumental support (%)
Ye s 91.7 95.6 96.1 97.0 95.5 91.8
No 6.3 2.6 2.5 1.8 3.3 5.7
Missing 2.0 1.8 1.4 1.2 1.2 2.4
Providing instrumental support (%)
Ye s 75.3 82.5 81.5 82.2 83.3 72.1
No 19.8 13.6 14.0 14.2 13.9 21.9
Missing 4.9 3.9 4.5 3.6 2.8 6.0
Frequency of exercising alone (%)
None 0.0 0.0 0.0 0.0 100.0 100.0
A few times/yr 7.8 0.0 13.4 24.3 0.0 0.0
1–3/mo 8.1 4.9 9.7 26.7 0.0 0.0
1/wk 11.4 9.4 12.3 29.6 0.0 0.0
2–3/wk 27.3 31.4 29.8 19.3 0.0 0.0
≥ 4wk 45.5 54.3 34.7 0.0 0.0 0.0
Frequency of exercising with others (%)
None 100.0 0.0 0.0 0.0 0.0 100.0
A few times/yr 0.0 30.9 13.4 0.0 20.4 0.0
1–3/mo 0.0 28.0 9.7 7.0 16.0 0.0
1/wk 0.0 26.2 12.3 14.5 18.5 0.0
2–3/wk 0.0 14.8 29.8 35.9 22.9 0.0
≥ 4wk 0.0 0.0 34.7 42.6 22.2 0.0
Continued

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when stratied analysis was performed using the collapsed groups reecting frequency of exercise per week.
ese results imply that increased frequency of exercise with others has important health benets regardless of
the total frequency of exercise, although exercising alone and exercising with others both seem to have health
benets.
In a previous study on middle-aged adults, there was no dierence between those who did not perform exer-
cise or play sports (the reference category) and those who exercised mostly alone, whereas there was a signi-
cantly lower OR of poor mental health later on among those who exercised mostly with others8. Similarly, in a
study on older adults, even for those exercising once a week or more, the risk of incident functional disability was
signicantly lower among those who participated in a sports organization compared to those who did not9. e
results of these previous studies are consistent with the nding in the present study that the OR of poor self-rated
health was signicantly lower among those exercising with others than those only exercising alone.
In those who exercised with others, the ORs for poor self-rated health seem to be smaller for those exercis-
ing both alone and with others (Ea > Ewo, Ea = Ewo and Ea < Ewo) than those who only exercised with others
(Ewo-only). is could still be residual confounding by total MET-hours, even though we were only crudely able
to adjust frequency of exercise (i.e. those performing both may be likely to be spending more total time exercising
compared to those only exercising alone). In contrast, the above-mentioned study on the association with mental
health did not nd any dierences in the risk of poor mental health between those exercising both alone and with
others and those who did not exercise et al.8. Although it is true that the reference for comparison was not the
same, the trend observed was dierent from that of the present study. One reason for this dierence may be that
those exercising both alone and with others accounted for over half of those who exercised in the present study,
which includes representative samples, but accounted for only 3% in the previous study.
Social relationships may be one mechanism underlying the health benefits of exercising with others4,20.
Reviews have indicated that poor social relationships can increase mortality risk6,7, and similar results were also
observed in older Japanese adults21. In addition, social connectedness while exercising contributes to exercise
adherence22. Previous studies examining the mechanism underlying the relationship between exercising with
others and health revealed the possibility that social relationships may contribute to the association between
participation in a sports organization and incidence of functional disability9,17. In this research, we used a part of
general social relationships (frequency of meeting friends, receiving instrumental support, providing instrumen-
tal support, receiving emotional support, and providing emotional support) as covariates which could serve as
measures of sociability. As we could not use specic social relationships in exercising with others, future studies
are needed to use specic social relationships in exercising with others to examine whether these social relation-
ships mediate the association between exercising with others and health. Other possible mechanisms that may
have a positive association with exercising with others are: adherence to exercise routines23–25, self-esteem and
other psychological factors5, social capital26 and other social factors4. For example, those who exercise with others
may have continued to exercise for more years at the time of the survey than those who exercise alone. As we
could not determine the roles of those factors in the present study, further studies are needed.
e present study had some limitations. Firstly, while we considered the frequency of exercise, which is an
important point when investigating the association between exercise and health, we did not consider intensity
or duration3, or type of exercise27. e dierences between exercising alone and exercising with others may be
residually confounded by dierences in these factors. e second limitation is that the phrase “exercise with oth-
ers” did not dierentiate between exercise with only one other person and exercise with two or more other people
or in a group or organization. Associations with health may dier between the dierent forms of exercise with
others. e third is that we used combinations of two variable categories for “total frequency of exercise”, which
may have resulted in a slight lack of accuracy. e fourth is that there may be a confounding eect from demo-
graphic and psychosocial factors related to exercising with others28, which we did not examine. e h is that
the study was cross-sectional, and therefore cannot determine causal relationships. Further studies are therefore
also needed to consider these points.
Ea-only Ea > Ewo Ea = Ewo Ea < Ewo Ewo-only Non-exercisers
Total frequency of exercise (%)
Non-exercisers 0.0 0.0 0.0 0.0 0.0 100.0
Category 1 7.8 0.0 0.0 0.0 20.4 0.0
Category 2 8.1 4.9 13.4 7.0 16.0 0.0
Category 3 11.4 9.4 9.7 14.5 18.5 0.0
Category 4 27.3 31.4 12.3 35.9 22.9 0.0
Category 5 45.5 54.3 64.5 42.6 22.2 0.0
Self-rated health (%) Poor 18.1 10.0 11.0 8.9 12.6 24.7
Table 1. Characteristics of individuals according to patterns of exercise. Ea-only: people who only exercised
alone. Ea > Ewo: people who reported exercising more frequently alone than with others. Ea = Ewo: people
who reported exercising alone or with others with equal frequency. Ea < Ewo: people who exercised with others
more frequently than exercising alone. Ewo-only: people who only exercised with others. Total frequency of
exercise (categories 1 to 3): people who exercised less than twice a week. Total frequency of exercise (categories
4 and 5): people who exercised at least twice a week. Results are presented as mean ± SD for continuous
variables and percentage (%) for categorical variables.

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Conclusion
Among older Japanese adults, although exercising alone and exercising with others both seem to have health ben-
ets, increased frequency of exercise with others has important health benets regardless of the total frequency of
exercise. A social interaction perspective may be useful to assist with promoting exercise benets for older adults.
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N
Crude Model 1 Model 2
OR 95%CI OR 95%CI OR 95%CI
All participants
Non-exercisers 6,195 ref —ref —
Ea-only 6,018 0.68 0.62–0.74 0.75 0.69–0.83
Ea > Ewo 3,685 0.34 0.30–0.38 0.50 0.43–0.57
Ea = Ewo 3,895 0.38 0.34–0.42 0.54 0.48–0.61
Ea < Ewo 760 0.30 0.23–0.39 0.43 0.33–0.56
Ewo-only 1,131 0.44 0.37–0.53 0.64 0.52–0.78
Exercisers-only: all participants excluding non-exercisers
Total frequency of exercise: Category 1–5 (all exercisers)
Ea-only 6,018 ref — Ref — ref —
Ea > Ewo 3,685 0.50 0.44–0.57 0.67 0.58–0.77 0.69 0.60–0.79
Ea = Ewo 3,895 0.56 0.50–0.63 0.72 0.63–0.82 0.74 0.64–0.84
Ea < Ewo 760 0.45 0.34–0.58 0.58 0.44–0.76 0.57 0.43–0.75
Ewo-only 1,131 0.66 0.54–0.79 0.86 0.70–1.05 0.79 0.64–0.97
Total frequency of exercise: Category 4–5 (exercisers ≥2/wk)
Ea-only 4,381 ref — Ref — ref —
Ea > Ewo 3,159 0.53 0.46–0.61 0.69 0.59–0.80 0.69 0.59–0.80
Ea = Ewo 2,995 0.57 0.50–0.65 0.73 0.62–0.85 0.76 0.65–0.90
Ea < Ewo 597 0.45 0.33–0.61 0.56 0.40–0.77 0.55 0.40–0.75
Ewo-only 510 0.60 0.45–0.80 0.80 0.58–1.09 0.78 0.57–1.06
Total frequency of exercise: Category 1–3 (exercisers <2/wk)
Ea-only 1,637 ref —ref —ref —
Ea > Ewo 526 0.54 0.41–0.71 0.72 0.54–0.97 0.69 0.51–0.93
Ea = Ewo 900 0.55 0.44–0.69 0.69 0.54–0.88 0.65 0.51–0.84
Ea < Ewo 163 0.46 0.28–0.76 0.65 0.39–1.10 0.62 0.37–1.05
Ewo-only 621 0.59 0.46–0.76 0.77 0.59–1.02 0.79 0.60–1.04
Table 2. Odds ratios of poor self-rated health according to patterns of exercise. Ea-only: people who only
exercised alone. Ea > Ewo: people who reported exercising more frequently alone than with others. Ea = Ewo:
people who reported exercising alone or with others with equal frequency. Ea < Ewo: people who exercised with
others more frequently than exercising alone. Ewo-only: people who only exercised with others. Model 1 was
adjusted for sex, age, equivalized income, educational attainment, household composition, occupational status,
self-reported medical conditions, IADL, depression, and sociability. Model 2 was adjusted for the covariates in
Model 1 plus total frequency of exercise.

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Acknowledgements
is study used data from the Japan Gerontological Evaluation Study (JAGES), which was supported by Health
Labour Sciences Research Grant (H28-Choju-Ippan-002, H26-Choju-Ippan-006, H25-Choju-Ippan-003, H25-
Kenki-Wakate-015, H25-Irryo-Shitei-003 (Fukkou), H24-Junkanki (Seisyu-Ippan-007)), JSPS (Japan Society for
the Promotion of Science) KAKENHI Grant Numbers (JP16H03249, JP15H01972, JP20319338, JP22390400,
JP23243070, JP23590786, JP23790710, JP24140701, JP24390469, JP24530698, JP24653150, JP24683018,
JP25253052, JP25282209, JP25870573, JP25870881, JP26882010), the Research Funding for Longevity Sciences
from National Center for Geriatrics and Gerontology (24–17, 24–23), Japan Foundation For Aging And Health
(J09KF00804), and Japan Agency for Medical Research and Development (AMED).
Author Contributions
Conceived and designed the experiments: S.K., T.T., S.I., Y.K. and K.K. Analyzed the data: S.K., T.T., S.I., Y.K., I.K.
and K.K. Wrote the paper: S.K., T.T., S.I., Y.K., I.K. and K.K. Acquisition of data: S.K., Y.K. and K.K.
Additional Information
Supplementary information accompanies this paper at http://www.nature.com/srep
Competing nancial interests: e authors declare no competing nancial interests.
How to cite this article: Kanamori, S. et al. Exercising alone versus with others and associations with subjective
health status in older Japanese: e JAGES Cohort Study. Sci. Rep. 6, 39151; doi: 10.1038/srep39151 (2016).
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