title: The Relationship of Objectively Measured Physical Activity and Sedentary Behaviour with Gestational Weight Gain and Birth Weight The association of daily physical activity and birth outcome: a population-based cohort study Adherence to physical activity guidelines in mid-pregnancy does not reduce sedentary time: an observational study Antenatal lifestyle advice for women who are overweight or obese: LIMIT randomised trial Effect of a behavioural intervention in obese pregnant women (the UPBEAT study): a multicentre, randomised controlled trial. GRADE guidelines: 4. Rating the quality of evidence--study limitations (risk of bias). Sedentary behaviors and abnormal glucose tolerance among pregnant Latina women. Sitting time and mortality from all causes, cardiovascular disease, and cancer. Too much sitting: the population health science of sedentary behavior. Physical Activity and Gestational Weight Gain in Hispanic Women Physical activity, sedentary behavior and risk of hypertensive disorders of pregnancy in Hispanic women Television watching and other sedentary behaviors in relation to risk of obesity and type 2 diabetes mellitus in women. Association between Physical Activity in Obese Pregnant Women and Pregnancy Outcomes: The UPBEAT Pilot Study GRADE guidelines: 3. Rating the quality of evidence. Physical activity of pregnant Hispanic women. Impact of an exercise intervention on physical activity during pregnancy: the behaviors affecting baby and you study.
abstract: Objective . To evaluate the relationship of physical activity ( PA ) and sedentary behaviour with  gestational weight gain ( GWG ) and birth weight . Design . Combined data from two prospect i ve studies : ( 1 ) nulliparous pregnant women without BMI restrictions and ( 2 ) overweight and obese pregnant women at risk for gestational diabetes . Methods . Daily PA and sedentary behaviour were measured with an accelerometer around 15 and at 32–35 weeks of gestation . The association between time spent in moderate-to-vigorous PA ( MVPA ) and in  sedentary activities  with GWG and birth weight was determined . Main outcome measures were GWG between 15 and 32 weeks of gestation , average GWG per week , and birth weight . Results . We studied 111 women . Early in pregnancy , 32 % of women spent ≥30 minutes/day in at least moderate PA versus 12 % in late pregnancy . No significant associations were found between time spent in MVPA or sedentary behaviour with GWG or birth weight . Conclusions . We found no relation  between MVPA and sedentary behaviour with GWG or birth weight . The small percentage of women meeting the recommended levels of PA indicates the need to inform and support pregnant women to maintain regular PA , as there seems to be no adverse effect on birth weight and maintaining PA increases overall health The potential relationship between daily physical activity and pregnancy outcome remains unclear because of the wide variation in study design s and physical activity assessment measures . We sought to prospect ively quantify the potential effects of the various domains of physical activity on selected birth outcomes in a large unselected population . The sample consisted of 11,759 singleton pregnancies from the Avon longitudinal study of parents and children , United Kingdom . Information on daily physical activity was collected by postal question naire for self-report measures . Main outcome measures were birth weight , gestational age at delivery , preterm birth and survival . After controlling for confounders , a sedentary lifestyle and paid work during the second trimester of pregnancy were found to be associated with a lower birth weight , while ‘ bending and stooping ’ and ‘ working night shifts ’ were associated with a higher birth weight . There was no association between physical exertion and duration of gestation or survival . Repetitive boring tasks during the first trimester was weakly associated with an increased risk of preterm birth ( < 37 weeks ) ( adjusted odds ratio [ OR ] = 1.25 , 95 % CI 1.04–1.50 ) . ‘ Bending and stooping ’ during the third trimester was associated with a reduced risk of preterm birth ( adjusted OR = 0.73 , 95 % CI 0.63–0.84 ) . Dem and ing physical activities do not have a harmful effect on the selected birth outcomes while a sedentary lifestyle is associated with a lower birth weight . In the absence of either medical or obstetric complications , pregnant women may safely continue their normal daily physical activities should they wish to do so Background Physical activity ( PA ) interventions design ed to prevent prenatal complications have focused on increasing moderate PA yielding conflicting results . Minimal attention has focused on the evaluation of sleep , sedentary behavior ( SB ) , light activity or total daily PA during pregnancy . The purpose of this prospect i ve , longitudinal study was to 1 ) objective ly quantify and compare habitual PA and SB during the 2nd and 3rd trimester ; and 2 ) evaluate differences in activity patterns for women meeting prenatal PA guidelines versus those that did not . Methods Forty-six participants wore 2 PA monitors ( SenseWear ® Mini and activPAL ™ ) during week 18 and week 35 of pregnancy . We compared differences in sleep duration , postural allocation , daily steps , and PA between the 2nd and 3rd trimester and for women who met and did not meet PA guidelines . Results During the 2nd trimester , 30 % of the women ’s day ( 24-hours ) was total sleep ; 52 % SB ; 13 % light ; 3 % moderate ; and 0 % vigorous PA . Light ( P = 0.05 ) , vigorous ( P = 0.02 ) , and moderate-vigorous PA ( MET-minutes ; P = 0.02 ) , decreased with a trend in increased SB ( P = 0.07 ) . Activity of other intensities and sleep duration did not significantly change . Only 39 % and 37 % of participants slept between 7–9 hours/night at week 18 and 35 , respectively . Forty-six percent ( n = 21 ) and 28 % ( n = 13 ) of participants met prenatal PA guidelines during the 2nd and 3rd trimester , respectively . At week 18 , no differences in total sleep , SB , or light PA existed for women who met PA guidelines versus those who did not ; total PA was significantly greater for women who met guidelines . At week 35 , women that met PA guidelines had significantly less SB ( P < 0.005 ) than women who did not . Conclusions This study demonstrates that pregnant women spend the majority of their day in SB . Significant reductions in total activity across pregnancy may be attributed , in part to shifts in light PA and increased SB . Based on the lifestyle of our sample , regardless of meeting PA guidelines in mid-pregnancy , no significant difference exists in time spent in SB , however meeting PA recommendations in late pregnancy may reduce SB . Future interventions should target reducing SB by increasing light and moderate PA beyond volitional exercise Objective To determine the effect of antenatal dietary and lifestyle interventions on health outcomes in overweight and obese pregnant women . Design Multicentre r and omised trial . We utilised a central telephone r and omisation server , with computer generated schedule , balanced variable blocks , and stratification for parity , body mass index ( BMI ) category , and hospital . Setting Three public maternity hospitals across South Australia . Participants 2212 women with a singleton pregnancy , between 10 + 0 and 20 + 0 weeks ’ gestation , and BMI ≥25 . Interventions 1108 women were r and omised to a comprehensive dietary and lifestyle intervention delivered by research staff ; 1104 were r and omised to st and ard care and received pregnancy care according to local guidelines , which did not include such information . Main outcome measures Incidence of infants born large for gestational age ( birth weight ≥90th centile for gestation and sex ) . Prespecified secondary outcomes included birth weight > 4000 g , hypertension , pre-eclampsia , and gestational diabetes . Analyses used intention to treat principles . Results 2152 women and 2142 liveborn infants were included in the analyses . The risk of the infant being large for gestational age was not significantly different in the two groups ( lifestyle advice 203/1075 ( 19 % ) v st and ard care 224/1067 ( 21 % ) ; adjusted relative risk 0.90 , 95 % confidence interval 0.77 to 1.07 ; P=0.24 ) . Infants born to women after lifestyle advice were significantly less likely to have birth weight above 4000 g ( lifestyle advice 164/1075 ( 15 % ) v st and ard care 201/1067 ( 19 % ) ; 0.82 , 0.68 to 0.99 ; number needed to treat ( NNT ) 28 , 15 to 263 ; P=0.04 ) . There were no differences in maternal pregnancy and birth outcomes between the two treatment groups . Conclusions For women who were overweight or obese , the antenatal lifestyle advice used in this study did not reduce the risk delivering a baby weighing above the 90th centile for gestational age and sex or improve maternal pregnancy and birth outcomes . Trial registration Australian and New Zeal and Clinical Trials Registry ( ACTRN12607000161426 ) BACKGROUND Behavioural interventions might improve clinical outcomes in pregnant women who are obese . We aim ed to investigate whether a complex intervention addressing diet and physical activity could reduce the incidence of gestational diabetes and large-for-gestational-age infants . METHODS The UK Pregnancies Better Eating and Activity Trial ( UPBEAT ) is a r and omised controlled trial done at antenatal clinics in eight hospitals in multi-ethnic , inner-city locations in the UK . We recruited pregnant women ( 15 - 18 weeks plus 6 days of gestation ) older than 16 years who were obese ( BMI ≥30 kg/m(2 ) ) . We r and omly assigned participants to either a behavioural intervention or st and ard antenatal care with an internet-based , computer-generated , r and omisation procedure , minimising by age , ethnic origin , centre , BMI , and parity . The intervention was delivered once a week through eight health trainer-led sessions . Primary outcomes were gestational diabetes ( diagnosed with an oral glucose tolerance test and by criteria from the International Association of Diabetes in Pregnancy Study Groups ) and large-for-gestational-age infants ( ≥90th customised birthweight centile ) . Analysis was by intention to treat . This trial is registered with Current Controlled Trials , ISCRTN89971375 . Recruitment and pregnancy outcomes are complete but childhood follow-up is ongoing . FINDINGS Between March 31 , 2009 , and June 2 , 2014 , we assessed 8820 women for eligibility and recruited 1555 , with a mean BMI of 36·3 kg/m(2 ) ( SD 4·8 ) . 772 were r and omly assigned to st and ard antenatal care and 783 were allocated the behavioural intervention , of which 651 and 629 women , respectively , completed an oral glucose tolerance test . Gestational diabetes was reported in 172 ( 26 % ) women in the st and ard care group compared with 160 ( 25 % ) in the intervention group ( risk ratio 0·96 , 95 % CI 0·79 - 1·16 ; p=0·68 ) . 61 ( 8 % ) of 751 babies in the st and ard care group were large for gestational age compared with 71 ( 9 % ) of 761 in the intervention group ( 1·15 , 0·83 - 1·59 ; p=0·40 ) . Thus , the primary outcomes did not differ between groups , despite improvements in some maternal secondary outcomes in the intervention group , including reduced dietary glycaemic load , gestational weight gain , and maternal sum-of-skinfold thicknesses , and increased physical activity . Adverse events included neonatal death ( two in the st and ard care group and three in the intervention group ) and fetal death in utero ( ten in the st and ard care group and six in the intervention group ) . No maternal deaths were reported . Incidence of miscarriage ( 2 % in the st and ard care group vs 2 % in the intervention group ) , major obstetric haemorrhage ( 1 % vs 3 % ) , and small-for-gestational-age infants ( ≤5th customised birthweight centile ; 6 % vs 5 % ) did not differ between groups . INTERPRETATION A behavioural intervention addressing diet and physical activity in women with obesity during pregnancy is not adequate to prevent gestational diabetes , or to reduce the incidence of large-for-gestational-age infants . FUNDING National Institute for Health Research , Guys and St Thomas ' Charity , Chief Scientist Office Scotl and , Tommy 's Charity In the GRADE approach , r and omized trials start as high- quality evidence and observational studies as low- quality evidence , but both can be rated down if most of the relevant evidence comes from studies that suffer from a high risk of bias . Well-established limitations of r and omized trials include failure to conceal allocation , failure to blind , loss to follow-up , and failure to appropriately consider the intention-to-treat principle . More recently recognized limitations include stopping early for apparent benefit and selective reporting of outcomes according to the results . Key limitations of observational studies include use of inappropriate controls and failure to adequately adjust for prognostic imbalance . Risk of bias may vary across outcomes ( e.g. , loss to follow-up may be far less for all-cause mortality than for quality of life ) , a consideration that many systematic review s ignore . In deciding whether to rate down for risk of bias -- whether for r and omized trials or observational studies -- authors should not take an approach that averages across studies . Rather , for any individual outcome , when there are some studies with a high risk , and some with a low risk of bias , they should consider including only the studies with a lower risk of bias UNLABELLED Studies conducted among nonpregnant population s have observed an association between sedentary behavior and glucose intolerance . Few studies have investigated this association during pregnancy , particularly among Latina women , a population with higher rates of sedentary behavior and abnormal glucose tolerance ( AGT ) as compared with non-Latina white women . OBJECTIVE The purpose of this study was to estimate the association between sedentary behavior and AGT . RESEARCH DESIGN AND METHODS We used data from the Latina gestational diabetes mellitus study , a prospect i ve cohort of 1231 Latina prenatal care patients in western Massachusetts .  Sedentary behavior  was assessed by bilingual interviewers using a modified version of the  Kaiser Physical Activity Survey  in prepregnancy , early pregnancy , and midpregnancy and defined as hours spent TV watching , frequency of sitting at work , and participation in sports or exercise activity as well as a derived composite of total sedentary activity . AGT was measured at 24 - 28 wk of gestation and abstract ed from medical records after delivery . Multivariate logistic regression was used to calculate odds ratios and 95 % confidence intervals . RESULTS A total of 12 % ( n = 119 ) of participants were classified as having AGT . After adjusting for AGT risk factors , sedentary behaviors in prepregnancy or in early pregnancy were not associated with AGT . However , in midpregnancy , low levels of participation in sports or exercise ( odds ratio = 2.01 , 95 % CI = 1.01 - 4.02 ) and increasing total sedentary activity ( Ptrend = 0.003 ) were associated with increased risk for AGT . CONCLUSIONS Findings suggest an association between sedentary activity in midpregnancy and risk of AGT in this understudied population PURPOSE Although moderate-to-vigorous physical activity is related to premature mortality , the relationship between sedentary behaviors and mortality has not been fully explored and may represent a different paradigm than that associated with lack of exercise . We prospect ively examined  sitting time  and mortality in a representative sample of 17,013 Canadians 18 - 90 yr of age . METHODS Evaluation of  daily sitting time  ( almost none of the time , one fourth of the time , half of the time , three fourths of the time , almost all of the time ) ,  leisure time physical activity , smoking status , and alcohol consumption  was conducted at baseline . Participants were followed prospect ively for an average of 12.0 yr for the ascertainment of mortality status . RESULTS There were 1832 deaths  ( 759 of cardiovascular disease ( CVD ) and 547 of cancer ) during 204,732 person-yr of follow-up . After adjustment for potential confounders , there was a progressively higher risk of mortality across higher levels of sitting time from all causes ( hazard ratios ( HR ) : 1.00 , 1.00 , 1.11 , 1.36 , 1.54 ; P for trend < 0.0001 ) and CVD ( HR:1.00 , 1.01 , 1.22 , 1.47 , 1.54 ; P for trend < 0.0001 ) but not cancer . Similar results were obtained when stratified by sex , age , smoking status , and body mass index . Age-adjusted all-cause mortality rates per 10,000 person-yr of follow-up were 87 , 86 , 105 , 130 , and 161 ( P for trend < 0.0001 ) in physically inactive participants and 75 , 69 , 76 , 98 , 105 ( P for trend = 0.008 ) in active participants across sitting time categories . CONCLUSIONS These data demonstrate a dose-response association between  sitting time  and mortality from all causes and CVD , independent of leisure time physical activity . In addition to the promotion of moderate-to-vigorous physical activity and a healthy weight , physicians should discourage sitting for extended periods Even when adults meet physical activity guidelines , sitting for prolonged periods can compromise metabolic health .  Television ( TV ) time and objective measurement studies show deleterious associations , and breaking up sedentary time is beneficial .  Sitting time , TV time , and time sitting in automobiles increase premature mortality risk . Further evidence from prospect i ve studies , intervention trials , and population -based behavioral studies is required Objective Hispanic women have high rates of excessive and inadequate gestational weight gain ( GWG )  according to Institute of Medicine ( IOM ) guidelines . Observational studies suggest that physical activity may be associated with GWG but have been conflicting and were largely conducted in non-Hispanic white population s. Design and Methods We prospect ively evaluated the association between physical activity and compliance with  GWG guidelines , total GWG , and rate of GWG among 1,276 Hispanic participants in Proyecto Buena Salud , a cohort study in Western Massachusetts . The Pregnancy Physical Activity Question naire was used to assess pre , early , mid , and late pregnancy physical activity according to both intensity ( i.e. , sedentary , moderate , and vigorous ) and type ( i.e. , housework/caregiving , occupational , and sports/exercise ) . Results A total of 26.9 % of women gained within IOM guidelines , 21.2 % had inadequate GWG , and 51.9 % experienced excessive GWG . Overall , we did not observe statistically significant associations between type or intensity of physical activity during pre , early , mid , and late pregnancy and inadequate or excessive GWG , total GWG , or rate of GWG . Conclusions In this prospect i ve cohort study of Hispanic women , after controlling for important risk factors , pregnancy physical activity did not appear to be associated with GWG Objective : Prior studies of the association between physical activity and  hypertensive disorders of pregnancy have been conflicting ; the majority focused on leisure-time activity only , did not use physical activity question naires vali date d for pregnancy , and were conducted in primarily non-Hispanic white population s. Methods : We prospect ively evaluated this association among 1240 Hispanic women in Proyecto Buena Salud . The Pregnancy Physical Activity Question naire , vali date d for use in pregnancy , was used to assess pre- and early pregnancy sports/exercise , household/caregiving , occupational and transportation activity . Diagnoses of hypertensive disorders of pregnancy were based on medical record abstract ion and confirmed by the study obstetrician . Results : A total of 49 women ( 4.0 % ) were diagnosed with a hypertensive disorder of pregnancy , including 32 women ( 2.6 % ) with pre-eclampsia . In age-adjusted analyses , high levels of early pregnancy household/caregiving activity were associated with reduced risk of total hypertensive disorders ( OR = 0.4 , 95 % CI 0.1–0.9 ) and pre-eclampsia ( OR = 0.3 , 95 % CI 0.1–0.9 ) relative to low levels ; however , these findings were no longer statistically significant in multivariable models . Pre-pregnancy activity and pattern of activity from pre- to early-pregnancy were not significantly associated with risk . Finally , sedentary behavior was not significantly associated with hypertensive disorders . Conclusion : Findings from this prospect i ve study of Hispanic women were consistent with those of prior prospect i ve cohorts indicating that physical activity prior to and during early pregnancy does not significantly reduce risk of hypertensive disorders of pregnancy CONTEXT Current public health campaigns to reduce obesity and type 2 diabetes have largely focused on increasing exercise , but have paid little attention to the reduction of sedentary behaviors . OBJECTIVE To examine the relationship between various sedentary behaviors , especially prolonged television ( TV ) watching , and risk of obesity and type 2 diabetes in women . DESIGN , SETTING , AND PARTICIPANTS Prospect i ve cohort study conducted from 1992 to 1998 among women from 11 states in the Nurses ' Health Study . The obesity analysis included 50 277 women who had a body mass index ( BMI ) of less than 30 and were free from diagnosed cardiovascular disease , diabetes , or cancer and completed questions on physical activity and sedentary behaviors at baseline . The diabetes analysis included 68 497 women who at baseline were free from diagnosed diabetes mellitus , cardiovascular disease , or cancer . MAIN OUTCOME MEASURES Onset of obesity and type 2 diabetes mellitus . RESULTS During 6 years of follow-up , 3757 ( 7.5 % ) of 50 277 women who had a BMI of less than 30 in 1992 became obese ( BMI > or = 30 ) . Overall , we documented 1515 new cases of type 2 diabetes .  Time spent watching TV was positively associated with risk of obesity and type 2 diabetes . In the multivariate analyses adjusting for age , smoking , exercise levels , dietary factors , and other covariates , each 2-h/d increment in TV watching was associated with a 23 % ( 95 % confidence interval [ CI ] , 17%-30 % ) increase in obesity and a 14 % ( 95 % CI , 5%-23 % ) increase in risk of diabetes ; each 2-h/d increment in sitting at work was associated with a 5 % ( 95 % CI , 0%-10 % ) increase in obesity and a 7 % ( 95 % CI , 0%-16 % ) increase in diabetes . In contrast , st and ing or walking around at home ( 2 h/d ) was associated with a 9 % ( 95 % CI , 6%-12 % ) reduction in obesity and a 12 % ( 95 % CI , 7%-16 % ) reduction in diabetes . Each 1 hour per day of brisk walking was associated with a 24 % ( 95 % CI , 19%-29 % ) reduction in obesity and a 34 % ( 95 % CI , 27%-41 % ) reduction in diabetes . We estimated that in our cohort , 30 % ( 95 % CI , 24%-36 % ) of new cases of obesity and 43 % ( 95 % CI , 32%-52 % ) of new cases of diabetes could be prevented by adopting a relatively active lifestyle ( < 10 h/wk of TV watching and > or = 30 min/d of brisk walking ) . CONCLUSIONS Independent of exercise levels , sedentary behaviors , especially TV watching , were associated with significantly elevated risk of obesity and type 2 diabetes , whereas even light to moderate activity was associated with substantially lower risk . This study emphasizes the importance of reducing prolonged TV watching and other sedentary behaviors for preventing obesity and diabetes Background : Obesity in pregnancy is associated with fetal macrosomia , a raised neonatal fat mass and an increased risk of obesity and poor metabolic health in childhood which persists into adulthood . The offspring of obese women are more likely to be obese than the offspring of lean women when they become pregnant themselves , perpetuating a cycle of obesity and its associated negative metabolic consequences . Increasing physical activity during pregnancy could improve insulin sensitivity and reduce the risk of maternal and offspring adverse outcomes . The UK Pregnancy Better Eating and Activity Trial ( UPBEAT ) is a trial of a complex intervention design ed to improve pregnancy outcomes through dietary changes and physical activity .  Data from the pilot trial of 183 women were available for analysis . The relationship between the time spent at different physical activity levels and maternal and infant pregnancy outcomes was examined . Key Messages : Strong evidence exists that physical activity improves insulin sensitivity in non-pregnant population s , and lifestyle interventions of proven effectiveness in non-pregnant population s have been developed . Women who are active in pregnancy demonstrate better glucose control and favourable pregnancy outcomes . There is a lack of effective interventions to support obese pregnant women to be physically active . Conclusions : No difference was detected in objective ly measured physical activity between women r and omised to the intervention and control arms of the UPBEAT pilot trial . Light-intensity physical activity was lower in early pregnancy in women who delivered macrosomic infants . Maternal sedentary time at 35 - 36 weeks ' gestation was positively associated and moderate-intensity physical activity was inversely associated with neonatal abdominal circumference . Maternal physical activity is associated with infant birth weight and abdominal circumference and is an appropriate target for intervention to improve infant outcomes . The challenge remains to develop an effective intervention to support obese pregnant women to be physically active This article introduces the approach of GRADE to rating  quality of evidence .  GRADE specifies four categories-high , moderate , low , and very low-that are applied to a body of evidence , not to individual studies . In the context of a systematic review , quality reflects our confidence that the estimates of the effect are correct . In the context of recommendations , quality reflects our confidence that the effect estimates are adequate to support a particular recommendation . R and omized trials begin as high- quality evidence , observational studies as low quality . " Quality " as used in GRADE means more than risk of bias and so may also be compromised by imprecision , inconsistency , indirectness of study results , and publication bias . In addition , several factors can increase our confidence in an estimate of effect . GRADE provides a systematic approach for considering and reporting each of these factors . GRADE separates the process of assessing quality of evidence from the process of making recommendations . Judgments about the strength of a recommendation depend on more than just the quality of evidence BACKGROUND A growing body of evidence suggests that physical activity during pregnancy can reduce risk of pregnancy complications . However , factors influencing activity in pregnant Hispanic women , who have high rates of sedentary activity as compared to non-Hispanic whites , are not well characterized . PURPOSE To assess patterns and correlates of physical activity among 1355 participants in Proyecto Buena Salud , a prospect i ve cohort of pregnant Hispanic women in Massachusetts from 2006 to 2011 . METHODS Analyses were conducted in 2012 . Pre- , early- , mid- , and late-pregnancy physical activity were assessed using the Pregnancy Physical Activity Question naire . Women reported the frequency and duration of household/caregiving , occupational , sports/exercise , and transportation activities  and were classified according to compliance with American College of Obstetricians and Gynecologists guidelines for physical activity . RESULTS Household/caregiving activity was the primary mode of pregnancy activity ranging from 56 % to 60 % of total activity while sports/exercise contributed the least ( < 10 % ) . Compared to nulliparous women , women with two or more children were 85 % less likely to become inactive at any time during pregnancy ( OR=0.15 , 95 % CI=0.04 , 0.56 , p-trend < 0.01 ) . Women with one or more children increased their total physical activity on average 9.73±2.04 MET-hours/week and 12.04±2.39 MET-hours/week , respectively , with the onset of pregnancy ( p<0.01 ) . Those with the highest levels of total physical activity prior to pregnancy were 87 % less likely to become inactive with the onset of pregnancy than those who were inactive prior to pregnancy ( OR=0.13 , 95 % CI= 0.05 , 0.29 ) . CONCLUSIONS Findings can inform culturally appropriate interventions design ed to reduce pregnancy complications through the promotion of physical activity during pregnancy OBJECTIVES We examined the impact of a prenatal exercise intervention on physical activity in 260 women at risk for gestational diabetes mellitus . METHODS We r and omized participants in the Behaviors Affecting Baby and You ( BABY ) Study , which took place from 2007 to 2012 , to either a 12-week individually tailored , motivationally matched exercise intervention ( n=132 ) or to a comparison health and wellness intervention ( n=128 ) . We assessed physical activity with the Pregnancy Physical Activity Question naire . We used linear mixed models to evaluate the impact of the interventions on change in physical activity according to intensity and type , total walking , and sedentary behavior . RESULTS Compared with the health and wellness arm , the exercise arm had significantly greater increases in sports or exercise activity ( 0.3 vs 5.3 metabolic equivalent of task [ MET ] hours/week ; P<.001 ) , and smaller declines in total activity ( -42.7 vs -2.1 MET hours/week ; P=.02 ) and activities of moderate to vigorous intensity ( -30.6 vs -10.6 MET hours/week ; P=.05 ) , and was more likely to achieve recommended guidelines for physical activity ( odds ratio=2.12 ; 95 % confidence interval=1.45 , 3.10 ) . CONCLUSIONS These findings extend the previous literature by demonstrating the benefits of a clinical ly feasible exercise intervention in an ethnically and socio-economically diverse population . Given the increased risk of adverse maternal health outcomes in ethnic minority groups , these findings may have important implication s for reducing health disparities
target: Increased time in sedentary behaviour was significantly associated with higher levels of C Reactive Protein and LDL Cholesterol , and a larger newborn abdominal circumference .
  Discrepancies were found in associations of sedentary behaviour with gestational weight gain , hypertensive disorders , and birth weight .
  No consistent associations were found between sedentary behaviour and other variables such as gestational diabetes .
  Conclusions Our review highlights the significant time spent in sedentary behaviour during pregnancy , and that sedentary behaviour may impact on pregnancy outcomes for both mother and child .
background: Background In the general population , at least 50 % of time awake is spent in sedentary behaviours .
  Sedentary behaviours are activities that expend less energy than 1.5 metabolic equivalents , such as sitting .
  The amount of time spent in sedentary behaviours is a risk factor for diseases such as type 2 diabetes , cardiovascular disease , and death from all causes .
  Even individuals meeting physical activity guidelines are at a higher risk of premature death and adverse metabolic outcomes if they sit for extended intervals .
  The associations between sedentary behaviour with type 2 diabetes and with impaired glucose tolerance are stronger for women than for men .
  It is not known whether sedentary behaviour in pregnancy influences pregnancy outcomes , but if those negative outcomes observed in general adult population also occur in pregnancy , this could have implication s for adverse outcomes for mothers and offspring .
  We aim ed to determine the proportion of time spent in sedentary behaviours among pregnant women , and the association of sedentary behaviour with pregnancy outcomes in mothers and offspring .