***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background Pharmacotherapies for smoking cessation have not been adequately tested in pregnancy and women are reluctant to use them . Behavioural support alone has a modest effect on cessation rates ; therefore , more effective interventions are needed . Even moderate intensity physical activity ( e.g. brisk walk ) reduces urges to smoke and there is some evidence it increases cessation rates in non-pregnant smokers . Two pilot studies assessed i ) the feasibility of recruiting pregnant women to a trial of physical activity for smoking cessation , ii ) adherence to physical activity and iii ) womens ' perceptions of the intervention . Methods Pregnant smokers volunteered for an intervention combining smoking cessation support , physical activity counselling and supervised exercise ( e.g. treadmill walking ) . The first study provided six weekly treatment sessions . The second study provided 15 sessions over eight weeks . Physical activity levels and continuous smoking abstinence ( verified by expired carbon monoxide ) were monitored up to eight months gestation . Results Overall , 11.6 % ( 32/277 ) of women recorded as smokers at their first antenatal booking visit were recruited . At eight months gestation 25 % ( 8/32 ) of the women achieved continuous smoking abstinence . Abstinent women attended at least 85 % of treatment sessions and 75 % ( 6/8 ) achieved the target level of 110 minutes/week of physical activity at end-of-treatment . Increased physical activity was maintained at eight months gestation only in the second study . Women reported that the intervention helped weight management , reduced cigarette cravings and increased confidence for quitting . Conclusion It is feasible to recruit pregnant smokers to a trial of physical activity for smoking cessation and this is likely to be popular . A large r and omised controlled trial is needed to examine the efficacy of this intervention Aerobic exercise can acutely reduce cigarette cravings during periods of nicotine deprivation . The primary aim of this study was to assess the differential effects of light and vigorous intensity aerobic exercise on cigarette cravings , subjective and physiological reactivity to smoking cues , and affect after overnight nicotine deprivation . A secondary aim was to examine cortisol change as a mediator of the effects of exercise on smoking motivation . 162 ( 55 female , 107 male ) overnight nicotine-deprived smokers were r and omized to one of three exercise conditions : light intensity , vigorous intensity , or a passive control condition . After each condition , participants engaged in a st and ardized cue reactivity assessment . Self-reported urges to smoke , affect , and salivary cortisol were assessed at baseline ( i.e. , before each condition ) , immediately after each condition , and after the cue reactivity assessment . Light and vigorous exercise significantly decreased urges to smoke and increased positive affect , relative to the control condition . In addition , those in the vigorous exercise condition demonstrated suppressed appetitive reactivity to smoking cues , as indexed by the startle eyeblink reflex . Although exercise intensity was associated with expected changes in cortisol concentration , these effects were not related to changes in craving or cue reactivity . Both light and vigorous exercise can reduce general cravings to smoke , whereas vigorous exercise appears especially well-suited for reducing appetitive reactions to cues that may precede smoking . Results did not support exercise-induced cortisol release as a mechanism for these effects Exercise has been hypothesized to curb increases in depressive symptoms often associated with smoking cessation . The relationship between increased fitness and changes in depressive symptoms was examined among 40 women who were abstinent at the end of an 8-week r and omized controlled trial . Participants received group-based , cognitive-behavioral smoking cessation treatment plus either exercise or contact control . All participants completed maximal fitness tests and question naires , including the Centers for Epidemiological Studies Depression Scale at baseline and at post-treatment . Regardless of treatment assignment , women who increased fitness over the 8-week treatment period were more likely to have decreases in depressive symptoms . Results indicate that increased fitness may benefit women by attenuating the depressive symptoms often associated with nicotine withdrawal INTRODUCTION AND OBJECTIVES To assess the efficacy of cardiac rehabilitation with a mixed primary and cardiological care program in patients with low-risk myocardial infa rct ion . PATIENTS AND METHOD The participants in this 12-month prospect i ve study were 153 consecutive patients with low-risk myocardial infa rct ion ( MI ) referred to their primary care center for follow-up care . Of these patients , 113 were referred to a mixed primary and specialized care program that included physical exercise , cardiovascular risk control , an antismoking program , health education talks and psychological evaluation . The other 40 patients served as controls . We analyzed the results after 3 months and 1 year of follow-up . RESULTS There were no differences between the two groups at baseline . After 1 year , improvements were seen in smoking habit ( 4.6 % vs 15.6 % ; P<.05 ) and body mass index ( 26 [ 2 ] vs 29 [ 2 ] ; P<.05 ) . Dyslipidemia , glucose and blood pressure were similar in both groups after follow-up . Greater improvements in the group of patients who participated in the program were seen after 1 year in quality of life ( 78 [ 2 ] vs 91 [ 2 ] ; P<.05 ) , exercise capacity ( 10.3 [ 2 ] vs 8.4 [ 3 ] ; P<<.01 ) and return to active employment ( 84.6 % vs 53.3 % ; P<.05 ) . CONCLUSIONS After 1 year of follow-up , the cardiac rehabilitation program coordinated by cardiological and primary care services for low-risk post-MI patients improved quality of life , and increased exercise tolerance , active employment , and the number of participants who quit smoking . The mixed program also reduced body mass index . These results suggest the need for similar programs Background Many women try to stop smoking in pregnancy but fail . One difficulty is that there is insufficient evidence that medications for smoking cessation are effective and safe in pregnancy and thus many women prefer to avoid these . Physical activity ( PA ) interventions may assist cessation ; however , trials examining these interventions have been too small to detect or exclude plausible beneficial effects . The London Exercise And Pregnant smokers ( LEAP ) trial is investigating whether a PA intervention is effective and cost-effective when used for smoking cessation by pregnant women , and will be the largest study of its kind to date . Methods / design The LEAP study is a pragmatic , multi-center , two-arm , r and omized , controlled trial that will target pregnant women who smoke at least one cigarette a day ( and at least five cigarettes a day before pregnancy ) , and are between 10 and 24 weeks pregnant . Eligible patients are individually r and omized to either usual care ( that is , behavioral support for smoking cessation ) or usual care plus a intervention ( entailing supervised exercise on a treadmill plus PA consultations ) . The primary outcome of the trial is self-reported and biochemically vali date d continuous abstinence from smoking between a specified quit date and the end of pregnancy . The secondary outcomes , measured at 1 and 4 weeks after the quit date , and at the end of pregnancy and 6 months after childbirth , are PA levels , depression , self-confidence , and cigarette withdrawal symptoms . Smoking status will also be self-reported at 6 months after childbirth . In addition , perinatal measures will be collected , including antenatal complications , duration of labor , mode of delivery , and birth and placental weight . Outcomes will be analyzed on an intention-to-treat basis , and logistic regression models used to compare treatment effects on the primary outcome . Discussion This trial will assess whether a PA intervention is effective when used for smoking cessation during pregnancy . Trial registration IS RCT This study examined the relationship between changes in physical activity and changes in smoking among adolescents . We prospect ively examined smoking progression , physical activity , demographic factors , and covariates in 978 high school students participating in a longitudinal cohort study of the predictors of smoking adoption . We used latent growth modeling with the parallel processes smoking progression and physical activity as our method , with smoking progression measured as an ordered categorical variable . Results indicated that higher levels of physical activity reduced the odds of progressing to smoking or a higher level of smoking by nearly 1.5 ( 1.44 ; P < 0.05 ) . No race differences were found . However , being male increased the odds of smoking progression by 1.32 ( P < 0.05 ) . Higher levels of physical activity may reduce the risk of smoking during adolescence . Youth smoking prevention initiatives should incorporate strategies to promote physical activity to prevent smoking experimentation and escalation Abstract The accurate assessment of both tobacco withdrawal and the impact of the nicotine patch on withdrawal may be compromised by attrition of subjects , or by subjects smoking during withdrawal . To reduce these occurrences , 211 participants were provided with intensive cessation counseling while trying to quit smoking with either nicotine ( 21 mg ) or placebo transdermal patches .  Subject attrition was low , with 80.5 % of participants continuing through the 5-week study period . Abstinence rates were also high over this period ( 75 % and 61 % in active and placebo groups , respectively ) . In this multisite , double-blind trial , withdrawal severity was assessed using a nine-item daily self-report question naire , and abstinence was confirmed via CO monitoring . Abrupt smoking cessation increased multiple tobacco withdrawal symptoms/signs including craving for cigarettes , irritability , anxiety , appetite , sleep disruption , difficulty concentrating , restlessness , depression , and impatience . Treatment with transdermal nicotine  reduced craving for cigarettes , anxiety , irritability , and appetite , as well as weight gain ( 1.85 versus 2.88 kg mean gain over 4 weeks in active and placebo groups , respectively ) Abstract Objective To compare the hazards of cigarette smoking in men who formed their habits at different periods , and the extent of the reduction in risk when cigarette smoking is stopped at different ages . Design Prospect i ve study that has continued from 1951 to 2001 . Setting United Kingdom . Participants 34 439 male British doctors . Information about their smoking habits was obtained in 1951 , and periodically thereafter ; cause specific mortality was monitored for 50 years . Main outcome measures Overall mortality by smoking habit , considering separately men born in different periods . Results The excess mortality associated with smoking chiefly involved vascular , neoplastic , and respiratory diseases that can be caused by smoking . Men born in 1900 - 1930 who smoked only cigarettes and continued smoking died on average about 10 years younger than lifelong non-smokers . Cessation at age 60 , 50 , 40 , or 30 years gained , respectively , about 3 , 6 , 9 , or 10 years of life expectancy . The excess mortality associated with cigarette smoking was less for men born in the 19th century and was greatest for men born in the 1920s . The cigarette smoker versus non-smoker probabilities of dying in middle age ( 35 - 69 ) were 42 % ν24 % ( a twofold death rate ratio ) for those born in 1900 - 1909 , but were 43 % ν 15 % ( a threefold death rate ratio ) for those born in the 1920s . At older ages , the cigarette smoker versus non-smoker probabilities of surviving from age 70 to 90 were 10 % ν 12 % at the death rates of the 1950s ( that is , among men born around the 1870s ) but were 7 % ν 33 % ( again a threefold death rate ratio ) at the death rates of the 1990s ( that is , among men born around the 1910s ) . Conclusion A substantial progressive decrease in the mortality rates among non-smokers over the past half century ( due to prevention and improved treatment of disease ) has been wholly outweighed , among cigarette smokers , by a progressive increase in the smoker ν non-smoker death rate ratio due to earlier and more intensive use of cigarettes . Among the men born around 1920 , prolonged cigarette smoking from early adult life tripled age specific mortality rates , but cessation at age 50 halved the hazard , and cessation at age 30 avoided almost all of it INTRODUCTION Quitting smoking is associated with weight gain , which may threaten motivation to engage or sustain a quit attempt . The pattern of weight gained by smokers treated according to smoking cessation guidelines has been poorly described . We aim ed to determine the weight gained after smoking cessation and its predictors , by smokers receiving individual counseling and nicotine replacement therapies for smoking cessation . METHODS We performed an ancillary analysis of a r and omized controlled trial assessing moderate physical activity as an aid for smoking cessation in addition to st and ard treatment in sedentary adult smokers . We used mixed longitudinal models to describe the evolution of weight over time , thus allowing us to take every participant into account . We also fitted a model to assess the effect of smoking status and reported use of nicotine replacement therapy at each time point . We adjusted for intervention group , sex , age , nicotine dependence , and education . RESULTS In the whole cohort , weight increased in the first 3 months , and stabilized afterwards . Mean 1-year weight gain was 3.3 kg for women and 3.9 kg for men ( p = .002 ) . Higher nicotine dependence and male sex were associated 
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The other studies showed no significant effect for exercise on abstinence .