3/8/17
TheBenefitsofSit-Stand:HypeorReal
ASSEBayArea2017
DavidRempel,MD,MPH,CPE
ProfessorEmeritus,DepartmentofMedicine
UniversityofCaliforniaSanFrancisco
Professor,DepartmentofBioengineering
UniversityofCalifornia,Berkeley
[Ihavenothingtodisclose]
Sit–StandandHealth
•  Reduceslowbackpain?
•  Reducescardiovascularrisk?
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Sit – Stand & LBP
Does prolonged sitting cause or aggravate LBP?
Does prolonged standing cause or aggravate LBP?
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Sit – Stand & LBP
Does prolonged sitting cause or aggravate LBP?
Does prolonged standing cause or aggravate LBP?
Sitting time increases LBP (Nourbakhsh et al. 2001)
Sitting time increases LBP (Gupta et al. 2015)
Sitting time does not increase LBP (Korshoj et al. 2017)
30% who stand experience LBP (Tissot et al. 2009)
Standing > 30 min increases LBP (Andersen et al., 2007)
Standing > 50% of workshift associated with LBP (Waters 2015)
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Pain Developers
Gallagher et al. 2012; Sorenson et al. 2015
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Sit – Stand & LBP
(Beach et al. Spine J 2005)
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Sit – Stand & LBP: Conclusions
Pain Developers (PD) vs Non-pain Developers (standing, sitting, both)
Standing greater contributor to LBP than sitting
Frequent early sit-stand change can reduce pain in PD
Transition 4-6 x per day
Standing: Monitor should be 2” higher than sitting
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UK2011&Australia2014
PublicHealthGuidelines
AdultsshouldminimizetheUmespentbeingsedentary
(siWng)forextendedperiods.
AMA2013
ProlongedsiWng,parUcularlyinworkseWngs,cancause
healthproblems.Businessesshouldofferemployees
alternaUvestosiWngallday–suchasstandingdesks,
isometricballsinsteadofdeskchairs,orre-arranging
officespaceandworkhabitstoencouragemore
movementduringtheday.
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Work hours and CVD
US Prospective PSID Population Survey 1986-2011, N=22,000; adjusted for
age, sex, industry, occupation. [Conway et al. JOEM 2016; 58(3):221]
PredictedWeightChanges
Church,Thomas,Tudor-Locke,etal.PLoSONE,2011
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Dosit-standworkstaAonsreduceCVDrisk?
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DoesoccupaUonalsiWngUmeincreaseCVD? DoesoccupaUonalphysicalacUvitydecreaseCVD?
DoesoccupaUonalstandingincreaseCVD?
Doessit-standreduceBMI? Doessit-standreducebloodpressure?
[OccupaUonalstandingincreaseslegvolume,leg
discomfort,andvaricoseveins] Words
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SiWngUme
StandingUme
Sedentarybehavior
PhysicalinacUvity
Nomoderate-to-vigorousphysicalacUvity
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DailyStandingTimeandAll-CauseMortality
[Katzmarzyk2009]
‘‘ForthoseacUviUeswhichyoudomostdaysof
theweek(suchaswork,schoolandhousework),
howmuchUmedoyouspendstanding?’’
17,013Canadians,ages18-90,(41%ofmortality=CVD),noadjustmentforcovariates
DailyStandingTimeandAll-CauseMortality
[Katzmarzyk2014]
Adjusted:age,smoking,alcohol,LTPA,physicalacUvityreadiness
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TotalSiWngTime&CVD(MI,CHD)
Study
N
Years
Followed
Age
HR
Comparison
VanDerPloeg2012(Norway)
222,497
2.8
45-75
1.40(1.27-1.55)
>11h/d
Borodulin2014(Finland)
4,516
8.6
25-74
1.06(1.01-1.11)
h/d
Petersen2014(Denmark)
71,363
5.4
18-99
1.59(1.19-2.15)
>10h/d
Maphews2015(USA)
154,614
6.8
59-82
1.42(1.21-1.66)
>12h/d
Chau2015**(Norway)
50,817
3.3
20-75
1.65(1.24-2.21)
>10h/d
**OccupaUonalsiWngUmedidnotincreaserisk
Adjustment:sex,age,employment,educaUon,smoking,LTPA,BMI,diet,alcohol,serum
cholesterol,hypertension
OccupaUonalSiWngTime&CVD(MI,CHD)
Study
N
Years
Followed
Age
Stamatakis2013(UK)
10,834
12.9
>40
Kikuchi2015(Japan)–Male*
15,863
10.0
40-74 0.87(0.75-1.01)
>3h/d
Kikuchi2015(Japan)–Female* 12,005
10.2
40-74 1.03(0.77-1.39)
>3h/d
Moller2016(Denmark)
12.2
21-70 0.99(0.92-1.06)
per10h/w
154,840
HR
Comparison
0.94(0.67-1.33) vStand-walk
*Officeworkers
Adjustment:sex,age,employment,educaUon,SES,smoking,LTPA,BMI,alcohol,serum
cholesterol,hypertension,waistcircumference,CVDatbaseline
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LondonBusDriversStudy
MorrisJetal.,Lancet1953.
DriversatincreasedriskforincidentCHD
comparedtoconductors:2.7v1.9/1000.
“Differencesduetodifferencesinphysical
acUvity”
LondonBusDriversStudy
MorrisJetal.,Lancet1953.
DriversatincreasedriskforincidentCHD
comparedtoconductors:2.7/1000vs1.9.
“Differencesduetodifferencesinphysical
acUvity”
Nocontrolforstress,BP,smoking,orBMI
UrbanbusdrivershaveelevatedBP.
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LeisureTimePhysicalAcAvity(LTPA)ReducesCVD
LTPAandCVD:
Meta-analysis
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[Lietal.,2013]
23prospecUvestudies
790,000adults
22,000incidents
Confounderscontrolled
ModeratelevelLTPA
reducedCVDrisk
20-30%
HighlevelLTPH
reducedCVDrisk
30-40%
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OccupaAonalPhysicalAcAvity(OPA)DoesNot
[Lietal.CurrentOpinioninCardiology.28(5):575-583,2013]
•  7prospecUvestudieswithadjustmentforcovariates
•  ModerateOPAincreasedrisk5-15%
•  HighOPAincreasedrisk10-30%
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TheOPA–LTPAHealthParadox
•  SystemaUcReview(Li2013):OPAisbad&LTPAisgood
•  Belgiancohort(Clays2012):OPAisbad&LTPAisonlygood
forthosewithlowOPA(OPA*LTPAInteracUon)
•  StaUcOPAincreasesBP&dynamicLTPAexercisereduces
BP–apossibleexplanaUonfortheparadox?(Clays2013)
•  Finnishcohort(Krause2015):OPA(energyexpenditure,kcal)
orrelaUveaerobicworkload(%VO2max)predict20-year
incidenceofAMI.LTPAnoeffect.
Doesaerobicexerciseatwork
increasefitness?
[KorshøjMetal.,SJWEH2014,EJAP2015,IAOEH2016,PLoS2016]
•  YES,aerobicexercise(4mo;30minx2/wk)RCT
amongDanishcleaners:increasedfitness&
reducedHR&reducedC-reacUveproteinandLDL.
•  BUTincreasedresUngandambulatorySBP(5mm
HG),especiallyaxerwork(10mmHG)amongthe
workerswhoexceededrelaUveaerobicworkload
recommendaUons(30%VO2max).
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StandingatWorkIncreasesCVD
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StandingIncreasesCaroAdAthersclerosis
Adjusted Mean Change in IMT (mm)
4-yearChangeofCaroAdInAmaMediaThickness(IMT),adjustedfor
Age,Technical,PhysicalandPsychosocialJobFactors,Income,
BiologicalandBehavioralFactors:MenwithIHD
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
none
little
quite a lot very much
Standing at Work
Krauseetal.,ScandJWorkEnvironHealth,2000
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Adjusted Mean Change in IMT (mm)
StandingcomparedtoSmoking
0.8
0.75
0.74
0.7
0.6
Standing
0.5
0.4
0.37
Smoking
0.38
0.3
0.2
0.1
0.15
0.08
0.15
0.09
0
none/none
little/ low quite a lot/
T
mid T
StandingatWork/Smoking
very
much/
upper T
Krauseetal.,ScandJWorkEnvironHealth,2000
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NEPA:Non-exercisephysicalac5vity
[LevineAJCN2000]
Lyingdown
SiWngmoUonless
StandingmoUonless
SiWng&FidgeAng
Standing&FidgeAng
Walking(1.6km/h)
Walking(3.2km/h)
Walking(4.8km/h)
kcal/h
77
80
87
118
148
196
235
305
SD
22
23
24
33
42
62
77
113
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NEPA:Non-exercisephysicalac5vity
Tudor-LockeCetal,IntJObesity2014
StandingvSiWng
TreadmillWalkingvSiWng SeatedPedalingvSiWng
0kcal/h(C:Speck2011)120kcal/h
56kcal/h
4kcal/h(Beers2008)
20kcal/h(B:Reiff2012)
UseofSit-StandWorkstaUons
•  Sit-standworkstaUonsleadtoincreased
standing50-70minutesperday.
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DoesWorkNEPAreduceBloodPressure?
8weekRCT[Gravesetal,2015]
Control(N=21)
SiWng Standing Walking 402min/d
44min/d
34min/d
Sit-StandDesk(N=23)
ΔSiWng -87.6min/d
ΔStanding 72.9min/d
ΔWalking 7.1min/d
ΔGlucose -0.09mmol/L
ΔTriglycerides0.11mmol/L
ΔCholersterol-0.40mmol/L
ΔSBP -1.6mmHg
ΔDBP -2.5mmHg
[AlldifferencesNS]
SiWngandLipidProfiles
[Saidj2013]
•  Danishworkingadults;N=2544;18-69yo
•  LeisureUmesiWng(3.1h)assocwithincreasedTGs,
cholesterol,bodyfat,BMI,waistcircumference.(no
assocwithHgbA1c,Plasmaglucose)
•  OccupaUonalUmesiWng(4.1h)noassociaUons
•  Adjusted:sex,age,ed,smoking,alcohol,diet,PA
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DoesWorkNEPAreduceBloodPressure?
4monthRCT[Mainsbridge,JOEM2014]
•  Everyhoursoxwareprompttostandupandmove
•  NEPAof8minutes/dayreducedresUngmeanarterial
pressure(MAP)by10mmHgaxer4months.
•  Strength:RCT
•  Limita5ons:
-smallsamples(N=11+18)
-randomizaUonnotsuccessful(controls5.5yearsolder)
-noblinding
-noage-adjustment
-nobetweengroup-effectsanalyzed,onlypre-post PredictedWeightChanges
Church,Thomas,Tudor-Locke,etal.PLoSONE,2011
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3/8/17
IncreasingOccupaUonalSiWngCausingObesityEpidemic?
DailyOccupaUonalEnergyExpenditure
Church,Thomas,Tudor-Locke,etal.PLoSONE,2011
-140dailykcals
-120dailykcals
USCaloricConsumpUonperDay
+900dailykcals
USDA,NHANES
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3/8/17
Conclusions
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AllUmesiWngincreasesCVD
OccupaUonalsiWngdoesnotincreasesCVD
StandingatworkincreasesCVD
OccupaUonalphysicalacUvitydoesnotdecreaseCVD
Noevidencethatsit-standworkstaUonsdecreaseCVD
MetabolisméwstandinginadequatetodecreaseBMI
StandingNEPAeffectsonBPuncertain
Sit-standworkstaUonsmaybebeneficialforLBP
Questions or Comments
[email protected]
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References:Sit-Stand
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AmericanHeartAssociaUonScienceAdvisory.SedentaryBehaviorandCardiovascular
MorbidityandMortality.CirculaUon2016;134:(ePub).
Borodulinetal.DailysedentaryUmeandriskofcardiovasculardisease:theNaUonalFINRISK
2002Study.JPhysActHealth2014;12(7):904-8.
ChauJYetal.Cross-secUonalassociaUonsoftotalsiWngandleisurescreenUmewith
cardiometabolicriskinadults,ResultsfromtheHUNTStudy.JSciMedSport2015;17:78-84.
ChurchTSetal.Trendsover5decadesinUSoccupaUonal-relatedphysicalacUvityandtheir
associaUonswithobesity.PLoSONE2011;6(5):e19657.
Eklundetal.DoesphysicalacUvityapenuate,oreveneliminate,thedetrimentalassociaUonof
siWngUmewithmortality?Aharmonizedmeta-analysis…Lancet2016;388:1302-1310
GravesLEFetal.EvaluaUonofsit-standworkstaUonsinanofficeseWng:arandomized
controlledtrial.BMCPubHealth2015;15:1145.
KatzmarzykP.StandingandmortalityinaprospecUvecohortofCanadianadults.Med&Sci
SportsExerc.2014;46(5):940-946.
Kikuchietal.OccupaUonalsiWngUmeandriskofall-causemortalityamongJapaneseworkers.
SJWEH2015;41(6):519-528.
Korshøjetal.,Doesaerobicexerciseimproveorimpaircardiorespiratoryfitnessandhealth
amongcleaners?Aclusterrandomizedcontrolledtrial.SJWEH2015;41(2):140-152.
Krauseetal.StandingatworkandprogressionofcaroUdatherosclerosis.SJWEH2000;26(3):
227-236.
References:Sit-Stand
Krauseetal.OccupaUonalphysicalacUvityand20-yearincidenceofacutemyocardial
infarcUon:resultsfromtheKuopioIschemicHeartDiseaseStudy.SJWEH2015;41(2):124-139.
LevineJAetal.EnergyexpenditureofnonexerciseacUvity.AmJClinNutr2000;72:1451-4.
Lietal.PhysicalacUvityandriskofcardiovasculardisease:whatdoesthenewepidemiological
evidenceshow?CurrOpinCardiol2013;28(5):575-583.
MainsbridgeCPetal.Theeffectofane-HealthintervenUondesignedtoreduceprolonged
occupaUonalsiUngonmeanarterialpressure.JOEM2014;56(11):1189-1194.
MaphewsCEetal.MortalitybenefitsforreplacingsiWngUmewithdifferentphysicalacUviUes.
MedSciSportsExer2015;47(9):1833-40.
MollerSVetal.MulU-wavecohortstudyofsedentaryworkandriskofischemicheartdisease.
SJWEH2016;42(1):43-51.
MorrisJetal.,Coronaryheart-diseaseandphysicalacUvityofwork.Lancet1953;28:1053-7
and1111-20.
PetersenCBetal.TotalsiWngUmeandriskofmyocardialinfarcUon,coronaryheartdisease
andall-causemortalityinaprospecUvecohortof....IntJBehavNutrPhysAct2014;11:13.
SaidjMetal.SeparateandjointassociaUonsofoccupaUonalandleisure-UmesiWngwith
cardio-metabolicriskfactors.PLOSOne2013;8(8):e70213.
StamatakisEetal.AresiWngoccupaUonsassociatedwithincreasedall-cause,canceter,and
cardiovasculardiseasemortalityrisk?Apooledanalysis….PLOSOne2013;8(9):e73753.
Tudor-LockeCetal.Changingthewaywework:elevaUngenergyexpenditurewithworkstaUon
alternaUves.IntJObesity2014;38:755-765.
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