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Physical ac i i y, body mass index and hea a e a iabili y-based s ess and eco e y
in 16 275 Finnish employees : a c oss-sec ional s udy
Föh , Tiina; Pie ilä, Julia; Helande , Elina; Myllymäki, Te o; Lindholm, Ha i; Rusko,
Heikki; Kujala, U ho
Föh , T., Pie ilä, J., Helande , E., Myllymäki, T., Lindholm, H., Rusko, H., & Kujala, U.
(2016). Physical ac i i y, body mass index and hea a e a iabili y-based s ess and
eco e y in 16 275 Finnish employees : a c oss-sec ional s udy. BMC Public Heal h,
16, A icle 701. h ps://doi.o g/10.1186/s12889-016-3391-4
2016
RESEARCH ARTICLE Open Access
Physical ac i i y, body mass index and
hea a e a iabili y-based s ess and
eco e y in 16 275 Finnish employees: a
c oss-sec ional s udy
Tiina Föh
1*
, Julia Pie ilä
2
, Elina Helande
2
, Te o Myllymäki
3
, Ha i Lindholm
4
, Heikki Rusko
5
and U ho M. Kujala
1
Abs ac
Backg ound: Physical inac i i y, o e weigh , and wo k- ela ed s ess a e majo conce ns oday. Psychological s ess
causes physiological esponses such as educed hea a e a iabili y (HRV), owing o a enua ed pa asympa he ic
and/o inc eased sympa he ic ac i i y in ca diac au onomic con ol. This s udy’s pu pose was o in es iga e he
ela ionships be ween physical ac i i y (PA), body mass index (BMI), and HRV-based s ess and eco e y on wo kdays,
among Finnish employees.
Me hods: The pa icipan s in his c oss-sec ional s udy we e 16 275 indi iduals (6863 men and 9412 women; age
18–65 yea s; BMI 18.5–40.0 kg/m
2
). Assessmen s o s ess, eco e y and PA we e based on HRV da a om bea - o-bea
R-R in e al eco ding (mainly o e 3 days). The alida ed HRV-de i ed a iables ook in o accoun he dynamics and
indi iduali y o HRV. S ess pe cen age ( he p opo ion o s ess eac ions, wo kday and wo king hou s), and s ess
balance ( a io be ween eco e y and s ess eac ions, sleep) desc ibe he amoun o physiological s ess and eco e y,
espec i ely. Va iables desc ibing he in ensi y (i.e. magni ude o ecognized eac ions) o physiological s ess and
eco e y we e s ess index (wo kday) and eco e y index (sleep), espec i ely. Mode a e o igo ous PA was measu ed
and pa icipan s di ided in o he ollowing g oups, based on calcula ed weekly PA: inac i e (0 min), low (0 < 150 min),
medium (150–300 min), and high (>300 min). BMI was calcula ed om sel - epo ed weigh and heigh . Linea models
we e employed in he main analyses.
Resul s: High PA was associa ed wi h lowe s ess pe cen ages (du ing wo kdays and wo king hou s) and s ess
balance. Highe BMI was associa ed wi h highe s ess index, and lowe s ess balance and eco e y index. These
esul s we e simila o men and women (P< 0.001 o all).
Conclusion: Independen o age and sex, high PA was associa ed wi h a lowe amoun o s ess on wo kdays.
Addi ionally, lowe BMI was associa ed wi h be e eco e y du ing sleep, exp essed by a g ea e amoun and
magni ude o eco e y eac ions, which sugges s ha PA in he long e m esul ing in imp o ed i ness has a
posi i e e ec on eco e y, e en hough high PA may dis u b eco e y du ing he ollowing nigh . Ob iously,
se e al ac o s ou side o he s udy could also a ec HRV-based s ess.
Keywo ds: Body mass index, Hea a e a iabili y, Physical ac i i y, Physiological s ess, S ess, S ess assessmen
* Co espondence: [email p o ec ed]
1
Depa men o Heal h Sciences, Uni e si y o Jy äskylä, P.O. Box 35FIN-40014
Jy äskylä, Finland
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Föh e al. BMC Public Heal h (2016) 16:701
DOI 10.1186/s12889-016-3391-4
Backg ound
Physical ac i i y (PA) is known o ha e posi i e e ec s
on heal h [1, 2]. Rou ine PA educes s ess and enhances
psychological wellbeing, which is pa icula ly impo an
o he p e en ion and managemen o ca dio ascula
disease, among o he ch onic diseases [3]. Regula PA is
known o educe he isk o many ad e se heal h ou -
comes. Some PA is be e han none; howe e , o mos
heal h ou comes, addi ional bene i s a e achie ed i he
amoun o PA inc eases h ough highe in ensi y, g ea e
equency, and/o longe du a ion. Acco ding o he
2008 Physical Ac i i y Guidelines o Ame icans, mos
heal h bene i s occu wi h a leas 150 o al minu es o
mode a e in ensi y o a leas 75 min o igo ous in en-
si y ae obic PA pe week. Howe e , addi ional bene i s
occu wi h mo e PA [4, 5]. In addi ion o he bene icial
e ec s o PA on physical heal h, hese guidelines a e also
ele an o men al heal h [6]. Al hough leisu e- ime PA
has inc eased among Finnish adul s [7], physical inac i -
i y is a majo p oblem and isk o heal h, in all coun-
ies. Fu he mo e, physical inac i i y is associa ed wi h
being o e weigh [8] and he cu en a e o o e weigh
adul s wo ldwide has been desc ibed as an epidemic o
e en a pandemic. This si ua ion is a majo public heal h
isk because being o e weigh is associa ed wi h diseases
including co ona y hea disease, s oke, diabe es and
cance [9].
Toge he wi h physical inac i i y and o e weigh , s ess
a wo k is a majo public heal h isk. I may e en lead o
ca dio ascula disease [10] wi hou comple e eco e y
[11]. S ess has been shown o educe pa icipa ion in
leisu e- ime PA [12, 13]. Fu he mo e, wo kplace s ess
may p edic a u u e inc eased isk o insu icien PA [14].
No mal weigh is associa ed wi h good sel - epo ed sub-
jec i e heal h [15], including low s ess le els [16, 17]. E i-
dence sugges s ha psychosocial s ess is associa ed wi h
he de elopmen o adiposi y [18]. Howe e , acco ding o
p e ious s udies, he associa ion be ween subjec i e s ess
and body composi ion is inconsis en , wi h e idence bo h
suppo ing [16, 19] and e u ing [20, 21] he idea ha
s ess is associa ed wi h adiposi y. A ecen sys ema ic e-
iew epo ed ha he associa ions o psychosocial ac o s
a wo k wi h weigh - ela ed ou comes we e weak and
somewha inconsis en [22].
Psychological s ess causes sympa he ic esponses in
he au onomic ne ous sys em (ANS), such as educed
hea a e a iabili y (HRV) [23]. HRV e e s o he a i-
a ion in in e als be ween hea bea s and e lec s ca diac
au onomic modula ion. Physiological s ess can be de-
ined as an inc eased body ac i a ion le el, when sympa-
he ic ac i i y domina es he ANS and pa asympa he ic
ac i a ion is low. S ess is associa ed wi h educed HRV,
owing o a enua ed pa asympa he ic and/o inc eased
sympa he ic ac i i y in ca diac au onomic con ol. Reco e y
e e s o a educed body ac i a ion le el, when pa asympa-
he ic ac i a ion domina es he ANS o e sympa he ic
ac i i y [24–26]. HRV analysis can be used as a comple-
men a y ool o assess gene al heal h [27]. HRV analysis
du ing sleep has he po en ial o explo e he sleeping b ain,
wi h possible implica ions o men al heal h [28]. P e ious
HRV-s udies ha e mainly used adi ional ime-domain
and equency-domain measu es o HRV, such as oo
mean squa e o successi e R-R in e als (RMSSD) and he
a io o low equency powe o high equency powe (LF/
HF a io). The adi ional measu es o HRV ep esen he
a e age le el o he au onomic ac i i y o e a pe iod o he
ime. Ca diac au onomic ac i i y is e y dynamic and a ies
du ing he day depending on s ess, eco e y and PA.
The e o e, he usabili y o he adi ional measu es o HRV
is limi ed in eal-li e condi ions. Addi ionally, hese mea-
su es a e e y indi idual which u he limi s hei usabili y
in s ess assessmen and clinical wo k. Howe e , i is also
possible o p o ide applied hea a e (HR) and HRV-
de i ed s ess and eco e y a iables ha ake in o accoun
he dynamic changes in au onomic ac i i y and indi idual-
i y o HRV including in o ma ion ha is di icul o ob ain
om adi ional measu es o HRV.
The majo i y o p e ious s udies on he associa ion o
PA wi h s ess ha e used subjec i e assessmen me hods
o adi ional measu es o HRV in he assessmen o
s ess. The p e ious s udies suppo he associa ion o
PA wi h inc eased HRV [29, 30]. Howe e , accu a e and
objec i e me hods a e needed o eliably assess PA, as
well as o assess HRV-based s ess and eco e y in eal-
li e. By u ilizing a me hod ha acknowledges he dynam-
ics and indi iduali y in HRV in eal-li e, he aim o his
s udy was o in es iga e he ex en o which PA and
BMI a e associa ed wi h HRV-based indica o s o s ess
and eco e y on wo kdays. The s udy was conduc ed
among 16 275 Finnish employees who had pa icipa ed
in bea - o-bea R-R in e al eco ding as a pa o li es yle
counseling be ween 2007 and 2015. Mo e speci ically, ac-
coun ing o age and sex, we in es iga ed he p e alence
o s ess and eco e y acco ding o he pa icipan s’ob-
jec i ely measu ed PA le el and sel - epo ed body mass
index (BMI). Uniqueness o he p esen s udy is in he in-
di idual and dynamic me hod used in he assessmen o
physiological s ess and eco e y.
Me hods
S udy design and pa icipan s
This c oss-sec ional s udy in es iga ed he amoun and in-
ensi y o objec i e HRV-based s ess and eco e y on
wo kdays in a eal-li e sample o 16 275 Finnish em-
ployees (6863 men and 9412 women; age 18–65 yea s;
BMI 18.5–40.0 kg/m
2
). The pa icipan s nonselec i ely
ep esen a c oss-sec ion o ypical Finnish employees in-
cluding bo h manual and non-manual labou employees.
Föh e al. BMC Public Heal h (2016) 16:701 Page 2 o 13
The majo i y o he pa icipan s we e appa en ly heal hy
wi hou ch onic diseases. The exclusion c i e ia o
pa icipa ion in he R-R in e al eco dings included se-
e e ca diac disease, e y high blood p essu e (≥180/
100 mmHg), ype 1 o 2 diabe es wi h au onomic neu -
opa hy, se e e neu ological disease, e e o o he acu e
disease, and BMI >40 kg/m
2
. These exclusion c i e ia ep-
esen ed by he analysis so wa e manu ac u e a e p e-
sen ed in de ail p e iously [31]. The cha ac e is ics o he
pa icipan s a e p esen ed in Table 1.
Da a collec ion
The no el me hodology used o de e mine he pa ici-
pan s’s ess, eco e y and le el o weekly PA, was based
on HRV da a om bea - o-bea R-R in e al eco dings.
These eco dings we e olun a ily pe o med on em-
ployees as a pa o he p e en i e occupa ional heal h
ca e p og ams p o ided by hei employe s be ween
2007 and 2015. The clinical pu pose o hese measu e-
men s is p esen ed comp ehensi ely in a p e ious pape
by Mu ikainen e al. [31]. The da a eco dings used in
he p e ious s udy we e ga he ed be ween 2007 and
2013, wi h a s udy popula ion size o 9554. These da a
we e used in he p esen s udy, supplemen ed wi h e-
co dings om 2014 o 2015. The s udy had a u he in-
clusion c i e ion o a minimum o 4.5 h bea - o-bea R-R
in e al eco ding du ing sleep a e a wo kday. Ano he
inclusion c i e ion was he a ailabili y o R-R in e al
da a, including a leas one wo kday (≥4 h o wo k) and
one day o , wi h a measu emen pe iod o 16–30 h/day
( om wake-up o wake-up). Pa icipan s who had con-
sumed alcohol on he moni o ing days we e excluded.
In o ma ion abou wo kdays, wo king hou s, days o
and sleep pe iods was ob ained om dia ies ha he pa -
icipan s we e eques ed o keep du ing he measu e-
men pe iod. The analyzed da a consis ed o success ully
eco ded (measu emen e o <15 % and <30-min e-
co ding b eak) days. The low o he pa icipan s in-
cluded in he analysis is p esen ed in Fig. 1.
HRV-based assessmen o PA, s ess and eco e y
Ambula o y bea - o-bea R-R in e al da a we e used o
de e mine he amoun and in ensi y o PA, s ess and e-
co e y. Using he Fi s bea Bodygua d de ice (Fi s bea
Technologies L d., Jy äskylä, Finland), eal-li e R-R
in e al da a we e eco ded, usually o e 3 days ( ypic-
ally wo wo kdays and one day o ) and analyzed using
Fi s bea Analysis Se e so wa e ( e sion 6.3, Fi s bea
Technologies L d.), which included a powe ul a i ac
de ec ion and co ec ion ea u e o i egula ec opic
bea s and signal noise. The so wa e calcula es HRV in-
dices second-by-second using he sho - ime Fou ie
ans o m me hod, and calcula es HR- and HRV-de i ed
a iables o espi a ion a e, oxygen consump ion, on-o
kine ics (inc easing o dec easing HR), and pa ame e s
desc ibing excess pos -exe cise oxygen consump ion
using neu al ne wo ks. The ea e , he so wa e di ides
he measu emen da a in o cohe en da a segmen s and
ca ego izes hese segmen s in o di e en physiological
s a es, such as PA o di e en in ensi ies, s ess and e-
co e y [32–34], by aking in o accoun indi idual cha -
ac e is ics (e.g. indi idual le els and scales o HR and
HRV, and he indi idual ela ionships be ween HRV and
au onomic con ol) [35]. The ca ego iza ion o he da a
is desc ibed in Addi ional ile 1: Table S1. Mo e in o ma-
ion abou his analysis me hod is a ailable in a pape by
Fi s bea Technologies L d. [36].
De ec ion o s ess and eco e y a iables
A e da a ca ego iza ion, he HRV-based a iables de-
sc ibing he amoun and in ensi y o s ess and eco e y
on wo kdays we e de ec ed. S ess pe cen ages (i.e. p o-
po ions o s ess eac ions, du ing he day and du ing
wo king hou s) and s ess balance ( a ios be ween eco -
e y and s ess eac ions du ing sleep) desc ibe he amoun
o s ess and eco e y, espec i ely. The a iables desc ib-
ing he in ensi y (i.e. magni ude o ecognized eac ions)
o s ess and eco e y we e s ess index (du ing he day)
and eco e y index (du ing sleep), espec i ely. These a i-
ables and hei calcula ions a e p esen ed in Addi ional ile
1: Table S1. The co ela ion coe icien be ween wo con-
secu i e wo kdays a ied om 0.74 o 0.88 o he ad-
i ional HRV a iables, om 0.64 o 0.93 o HRV-de i ed
a iables o s ess, and om 0.42 o 0.49 o HRV-de i ed
a iables o eco e y du ing sleep.
Calcula ion o weekly PA
Backg ound in o ma ion abou age, sex, sel - epo ed
heigh and weigh , and sel - epo ed PA class [37] modi-
ied om Ross and Jackson [38], was collec ed in
Table 1 Cha ac e is ics o he pa icipan s
Va iable All (n= 16275) Men (n= 6863) Women (n= 9412)
Mean ± SD Min Max Mean ± SD Min Max Mean ± SD Min Max
Age 44.8 ± 9.9 18.0 65.0 44.5 ± 9.9 18.0 65.0 45.0 ± 9.9 18.0 65.0
Body mass index (kg/m
2
) 26.0 ± 4.1 18.5 40.0 26.6 ± 3.5 18.6 40.0 25.5 ± 4.4 18.5 40.0
Sel - epo ed ac i i y class 0–10 4.8 ± 1.8 0.0 10.0 4.9 ± 1.9 0.0 10.0 4.8 ± 1.8 0.0 10.0
Physical ac i i y (mins/week) 186 ± 227 0 2629 246 ± 258 0 2629 142 ± 189 0 1865
Föh e al. BMC Public Heal h (2016) 16:701 Page 3 o 13
conjunc ion wi h R-R in e al eco dings using ques ion-
nai es. Backg ound in o ma ion was used o es ima e
maximal HR [39] and maximal VO
2
[40] which we e
hen used in he es ima ion o VO
2
. The maximal HR
used o u he calcula ions was co ec ed acco dingly i
a pe iod wi h HR highe han he es ima ed maximal
was ound om he eco ding. F om he second-by-
second VO
2
es ima ions, each pa icipan ’s mean VO
2
o each minu e o he measu emen day was calcula ed.
The minu e-by-minu e VO
2
es ima ions we e hen con-
e ed o mul iples o he es ing me abolic a e (MET)
by di iding he VO
2
alues by 3.5. The o al numbe o
1-min segmen s wi hin he ollowing h esholds: mode -
a e PA 3 o <6 METs and igo ous PA ≥6 METs, du ing
each measu emen day (including days o ), we e calcu-
la ed. Con inuous bou s o PA las ing o ≥10 min we e
included in he es ima ion o weekly PA. These con inu-
ous bou s o PA we e calcula ed sepa a ely o wo kdays
and days o , and, i he measu emen pe iod included
wo o mo e wo kdays o days o , an a e age was cal-
cula ed. The ac i i y minu es sco e o each day (mod-
e a e PA minu es + igo ous PA minu es × 2) was
calcula ed. The ea e , he amoun o PA was ex apo-
la ed using he ollowing o mula: PA minu es pe
week = (5 × mean wo kday ac i i y sco e) + (2 × mean
day-o ac i i y sco e). These calcula ions ha e been
p e iously desc ibed in mo e de ail [31]. Based on he
weekly PA minu es, he pa icipan s we e di ided in o
he ollowing PA g oups: inac i e (0 min), low (0 <
150 min), medium (150–300 min) and high (>300 min).
Assessmen o body composi ion
BMI was calcula ed om he sel - epo ed weigh and
heigh (kg/m
2
). The pa icipan s we e hen di ided
in o he ollowing g oups: no mal weigh (18.5 o
<25 kg/m
2
), o e weigh (25 o <30 kg/m
2
) and obese
(30–40 kg/m
2
).
Analysis
Da a p ocessing and s a is ical analysis we e pe o med
using R 3.2.2 e sion (R Founda ion o S a is ical Com-
pu ing). P- alues we e wo-sided and a p- alue o <0.05
was conside ed s a is ically signi ican . Because o he
size o he da a, 99 % con idence in e als (CIs) we e de-
e mined (Fig. 2) ins ead o con en ional 95 % CIs.
The main ou come a iables o he s udy we e s ess
pe cen age and s ess index, calcula ed o he whole
day, s ess pe cen age calcula ed o wo king hou s, and
s ess balance and eco e y index calcula ed o sleep.
These a iables we e de i ed om he bea - o-bea R-R
in e al eco dings on wo kdays. Fo a mo e de ailed de-
sc ip ion o he a iables see Addi ional ile 1: Table S1.
In addi ion, HR and adi ional HRV pa ame e s, includ-
ing RMSSD and he LF/HF a io, we e calcula ed om
he bea - o-bea R-R in e al eco dings on wo kdays.
These a iables we e calcula ed sepa a ely o waking
hou s and sleep, and RMSSD was calcula ed using a 5-
min window. I he measu emen pe iod o a subjec in-
cluded wo o mo e wo kdays, an a e age was calcula ed
and he mean alues o he ou come a iables we e used
in he analysis.
Fig. 1 Flow o he pa icipan s and measu emen days included in he analysis (BMI, body mass index)
Föh e al. BMC Public Heal h (2016) 16:701 Page 4 o 13

Fo he desc ip i e s a is ics, he means and s anda d
de ia ions o he ou come a iables we e calcula ed sep-
a a ely o men and women, and s a i ied based on PA,
BMI and age. Di e ences in he ou come a iables be-
ween PA, BMI and age g oups we e es ed using he
K uskal-Wallis es . The esul s a e shown in Addi ional
ile 2: Tables S2-S4. To show he e ec s o BMI and PA
g oup on he HRV-based s ess and eco e y a iables,
he age-con olled mean alues and 99 % CIs o he
HRV-based s ess and eco e y a iables, by BMI and
PA g oup, a e p esen ed in Fig. 2.
Linea models we e employed o s udy he e ec s o
PA g oup, BMI and age on HRV-based s ess and eco -
e y a iables. In he models, age and BMI we e inco po-
a ed as con inuous p edic o a iables and objec i ely
measu ed PA g oup was inco po a ed as a ca ego ical
p edic o a iable. The models we e gene a ed sepa a ely
o men and women. The e e ence alue o age was se
o 18 yea s and o BMI o 18.5 kg/m
2
. A simple linea
leas squa es eg ession model (p ocedu e lm in R) was
applied o p edic he s ess pe cen age du ing he day.
As con i med by isual inspec ion, he assump ion o
Fig. 2 S ess and eco e y by physical ac i i y and body mass index g oups wi h age-con olled mean alues and 99 % CIs o ou pu a iables.
Physical ac i i y g oups: inac i e (0 min/week), ed ●; low (0 < 150 min/week), black ▲; medium (150–300 min/week), blue ■; high (>300 min/
week), g een ♦
Föh e al. BMC Public Heal h (2016) 16:701 Page 5 o 13
linea eg ession conside ing he no mal dis ibu ion o
he esiduals was no ul illed o s ess pe cen age du -
ing wo king hou s, s ess index and eco e y index.
Thus, a Box-Cox ans o ma ion was applied on hese
dependen a iables [41]. The Box-Cox coe icien was
de e mined by maximizing he log-likelihood unc ion
and was ounded o wo decimal places be o e ans o m-
a ion. Tobi eg ession model (p ocedu e glm using i e a-
i ely eweigh ed leas squa es in R) was applied o
modeling s ess balance wi h a ixed lowe and uppe limi
o −1 and 1, espec i ely. The in e ac ions o he p edic-
o s we e no included in he inal eg ession models be-
cause he coe icien o de e mina ion o he in e ac ion
models was only a ew pe cen age poin s g ea e han o
he simple models.
Resul s
The o al numbe o wo kdays included in he analysis
was 28 314, wi h measu emen s ob ained om 16 275
pa icipan s (men 6863; women 9412). The pa icipan s’
cha ac e is ics a e shown in Table 1. The pa icipan s’
mean age was 44.8 yea s (44.5 yea s o men; 45.0 yea s
o women) and he mean BMI was 26.0 kg/m
2
(26.6 kg/
m
2
o men; 25.5 kg/m
2
o women). The pa icipan s’
mean sel - epo ed ac i i y class was 4.8 (4.9 o men;
4.8 o women) indica ing ha , on a e age, he pa ici-
pan s we e in ol ed in PA 2–3 imes pe week and hei
o al weekly PA was abou 2 h. The mean weekly mi-
nu es o objec i e moni o ing-based PA was 186 (246 o
men; 142 o women). The mean weekly minu es o PA
in he g oup o low PA was 78 o men and 74 o
women, in he g oup o medium PA 222 o men and
215 o women, and in he g oup o high PA 545 o
men and 496 o women. The numbe o pa icipan s in
he PA, BMI, and age g oups is p esen ed in Addi ional
ile 3: Table S5.
Di e ences in ou come a iables be ween PA g oups
(Addi ional ile 2: Table S2) we e s a is ically signi ican
excep o LF/HF a io du ing waking hou s and sleep,
s ess balance in men, and HR and s ess balance in
women. Fo bo h men and women, he high PA g oup
had he highes RMSSD (du ing waking hou s and du -
ing sleep) and eco e y index, and he lowes s ess pe -
cen age (du ing he day and du ing wo king hou s) and
s ess index.
Di e ences in ou come a iables be ween BMI g oups
we e s a is ically signi ican o bo h men and women
(Addi ional ile 2: Table S2). No mal-weigh indi iduals
had he highes RMSSD (bo h du ing waking hou s and
du ing sleep), s ess balance and eco e y index, he
lowes s ess pe cen age du ing he day and he lowes
s ess index. S ess pe cen age du ing wo king hou s
was lowes in obese indi iduals.
In bo h sexes, di e ences in ou come a iables we e
s a is ically signi ican be ween age g oups, excep o
HR du ing sleep in women (Addi ional ile 2: Table S3).
The younges age g oup (18–30 yea s) had he highes
RMSSD (bo h du ing waking hou s and du ing sleep),
s ess balance and eco e y index, and he lowes s ess
index. S ess pe cen ages du ing he day we e lowes in
he younges age g oup in women, and in he oldes age
g oup (51–65 yea s) in men. S ess pe cen ages du ing
wo king hou s we e lowes in he oldes age g oup in
bo h sexes.
Figu e 2 shows he e ec o PA and BMI g oup on he
s ess and eco e y a iables wi h he e ec o age con-
olled. The high PA g oup had he lowes mean s ess
pe cen age du ing he day and du ing wo king hou s in
all h ee BMI g oups, a e adjus men o age (Fig. 2).
Mean s ess index alues inc eased as he BMI g oup
changed om no mal weigh o o e weigh and o e -
weigh o obese, ega dless o he PA g oup. In addi ion,
ega dless o he PA g oup, obese indi iduals had he
lowes s ess balance and eco e y index.
The linea model esul s a e shown in Table 2. Medium
(P<0.05)andhigh(P< 0.001) PA g oups, lowe BMI (P<
0.001), and olde age (P< 0.001) we e associa ed wi h
lowe s ess pe cen ages du ing he day. Medium (P<
0.05) and high (P< 0.001) PA le el, highe BMI (P<
0.001), and olde age (P< 0.001) we e associa ed wi h
lowe s ess pe cen ages du ing wo king hou s. S ess pe -
cen age esul s du ing he day and du ing wo king hou s
we e simila o men and women. Highe BMI (P<0.001)
and olde age (P< 0.001) we e associa ed wi h highe
s ess index, bo h in men and in women. In addi ion,
medium (P<0.01) and high(P< 0.01) PA we e associa ed
wi h lowe s ess index in women.
Medium (P< 0.01) and high (P< 0.001) PA, and highe
BMI (P< 0.001) we e associa ed wi h lowe s ess bal-
ance, bo h in men and in women. Mo eo e , olde age
was associa ed wi h lowe s ess balance in men (P<
0.001). Highe BMI and olde age we e associa ed wi h
lowe eco e y index, in men and in women (P< 0.001).
BMI explained he highes p opo ion o a iance in
s ess balance (2.2 % o men and 3.1 % o women)
compa ed wi h PA and age.
Discussion
The pu pose o his s udy was o in es iga e he amoun
and in ensi y o objec i e HRV-based s ess and eco e y
on wo kdays. The sample g oup comp ised 16 275
Finnish employees, who had pa icipa ed in bea - o-bea
R-R in e al eco ding as a pa o li es yle counseling in
he cou se o hei e e yday li es be ween 2007 and
2015. Mo e speci ically, he ela ionships be ween PA,
BMI, and HRV-based s ess and eco e y we e in es i-
ga ed. Fo bo h sexes, a high le el o PA and lowe BMI
Föh e al. BMC Public Heal h (2016) 16:701 Page 6 o 13
Table 2 Resul s o he linea models
Men Women
Pa ame e
Es ima e
95 % Cl Lowe Uppe P alue Va iance
explained (%)
Pa ame e
Es ima e
95 % Cl Lowe Uppe P alue Va iance
explained (%)
S ess (%), 24 h
a
2.356
h
1.476
h
In e cep 52.3153 50.7730 53.8575 <0.001 50.0658 48.9790 51.1527 <0.001
Age (18 yea s = 0) −0.1263 −0.1600 −0.0926 <0.001 0.780
i
−0.0869 −0.1151 −0.0587 <0.001 0.387
i
BMI (18.5 kg/m
2
= 0) 0.1541 0.0580 0.2502 0.002 0.144
i
0.0909 0.0264 0.1553 0.006 0.081
i
Physical ac i i y le el (inac i e = 0) 1.586
i
1.050
i
Low physical ac i i y class 0.3235 −0.6903 1.3372 0.53 −0.8892 −1.5471 −0.2313 0.008
Medium physical ac i i y class −1.1405 −2.2144 −0.0667 0.04 −1.9539 −2.7608 −1.1470 <0.001
High physical ac i i y class −3.9695 −5.0062 −2.9328 <0.001 −4.3772 −5.2620 −3.4923 <0.001
S ess (%), wo king hou s
b
4.152
h
1.721
h
In e cep 807.3480 777.0476 837.6483 <0.001 677.8091 656.0738 699.5443 <0.001
Age (18 yea s = 0) −4.8729 −5.5355 −4.2103 <0.001 2.942
i
−2.66482 −3.22838 −2.10127 <0.001 0.905
i
BMI (18.5 kg/m
2
=0) −4.6640 −6.5515 −2.7766 <0.001 0.341
i
−4.54067 −5.82984 −3.25149 <0.001 0.504
i
Physical ac i i y le el (inac i e = 0) 1.590
i
0.584
i
Low physical ac i i y class −5.5094 −25.4261 14.4073 0.59 −3.40975 −16.5664 9.746938 0.61
Medium physical ac i i y class −24.7847 −45.8819 −3.6874 0.021 −17.9339 −34.0695 −1.79829 0.030
High physical ac i i y class −85.2896 −105.6576 −64.9215 <0.001 −61.7878 −79.4833 −44.0923 <0.001
S ess index, 24 h
c
27.113
h
27.448
h
In e cep 1.2406 1.2403 1.2409 <0.001 1.2414 1.2412 1.2417 <0.001
Age (18 yea s = 0) 0.0001 0.0001 0.0001 <0.001 21.992
i
0.0001 0.0001 0.0001 <0.001 19.655
i
BMI (18.5 kg/m
2
= 0) 0.0002 0.0001 0.0002 <0.001 3.819
i
0.0001 0.0001 0.0001 <0.001 3.031
i
Physical ac i i y le el (inac i e = 0) 0.115
i
0.145
i
Low physical ac i i y class 0.0002 0.0000 0.0004 0.024 −0.0001 −0.0003 0.0000 0.031
Medium physical ac i i y class 0.0000 −0.0002 0.0002 0.91 −0.0002 −0.0004 −0.0001 0.002
High physical ac i i y class 0.0001 −0.0001 0.0003 0.47 −0.0003 −0.0004 −0.0001 0.002
S ess balance, sleep
e
3.669
h
3.244
h
In e cep 1 0.9975 0.9287 1.0663 <0.001 0.6166 0.5672 0.6661 <0.001
In e cep 2 −0.5292 −0.5503 −0.5082 <0.001 −0.5537 −0.5705 −0.5368 <0.001
Age (18 yea s = 0) −0.0066 −0.0081 −0.0052 <0.001 1.153
i
−0.0007 −0.0019 0.0006 0.31 0.006
i
BMI (18.5 kg/m
2
=0) −0.0273 −0.0315 −0.0231 <0.001 2.179
i
−0.0253 −0.0282 −0.0224 <0.001 3.080
i
Physical ac i i y le el (inac i e = 0) 0.445
i
0.233
i
Low physical ac i i y class −0.0715 −0.1162 −0.0269 0.002 −0.0126 −0.0423 0.0172 0.41
Föh e al. BMC Public Heal h (2016) 16:701 Page 7 o 13
Table 2 Resul s o he linea models (Con inued)
Medium physical ac i i y class −0.0799 −0.1272 −0.0326 <0.001 −0.0572 −0.0937 −0.0207 0.002
High physical ac i i y class −0.1327 −0.1784 −0.0870 <0.001 −0.0822 −0.1222 −0.0421 <0.001
Reco e y index, sleep
9.685
h
3.297
h
In e cep 592375.4298 573358.1497 611392.7100 <0.001 457913.8301 444648.7930 471178.8673 <0.001
Age (18 yea s = 0) −5092.7330 −5508.5947 −4676.8712 <0.001 7.753
i
−2100.7061 −2444.6430 −1756.7692 <0.001 1.501
i
BMI (18.5 kg/m
2
=0) −4825.0722 −6009.6783 −3640.4662 <0.001 0.921
i
−4038.5841 −4825.3668 −3251.8014 <0.001 1.065
i
Physical ac i i y le el (inac i e = 0) 0.154
i
0.026
i
Low physical ac i i y class −19214.5686 −31714.7934 −6714.3437 0.003 1051.0555 −6978.4656 9080.5766 0.80
Medium physical ac i i y class −6153.1124 −19394.2693 7088.0445 0.36 −4452.2347 −14299.7786 5395.3093 0.38
High physical ac i i y class −9653.5430 −22437.0465 3129.9606 0.14 −5732.9247 −16532.4796 5066.6302 0.30
BMI body mass index
a
Linea eg ession
b
Box-Cox linea eg ession using ans o ma ion coe icien o 1.62
c
Box-Cox linea eg ession using ans o ma ion coe icien o −0.79
e
Tobi eg ession
Box-Cox linea eg ession using ans o ma ion coe icien o 3.18
h
The p opo ion o a iance explained by he whole model
i
The p opo ion o a iance explained by he p edic o a iable. Calcula ed as he di e ence be ween he p opo ion o a iance explained by he whole model and he p opo ion o a iance explained by a model
including all he p edic o a iables, excep o he p edic o in ques ion
Föh e al. BMC Public Heal h (2016) 16:701 Page 8 o 13