title: The effects of 60 minutes of brisk walking per week, accumulated in two different patterns, on cardiovascular risk. Associations Between Physical Activity and BMI, Body Fatness, and Visceral Adiposity in Overweight or Obese Latino and Non-Latino Adults The Effects of Single Long and Accumulated Short Bouts of Exercise on Cardiovascular Risks in Male Japanese Workers: A Randomized Controlled Study Effects of Long versus Short Bout Exercise on Fitness and Weight Loss in Overweight Females Moderate to Vigorous Physical Activity and Weight Outcomes: Does Every Minute Count? TWO SHORT,DAILY ACTIVITY BOUTS VS.ONE LONG BOUT: ARE HEALTH AND FITNESS IMPROVEMENTS SIMILAR OVER TWELVE AND TWENTY‐FOUR WEEKS? Walking trials in postmenopausal women: effect of one vs two daily bouts on aerobic fitness. Effects of intermittent exercise and use of home exercise equipment on adherence, weight loss, and fitness in overweight women: a randomized trial. Prescribing exercise in multiple short bouts versus one continuous bout: effects on adherence, cardiorespiratory fitness, and weight loss in overweight women. Walking trials in postmenopausal women: effect of low doses of exercise and exercise fractionization on coronary risk factors.
abstract: BACKGROUND Current ACSM guidelines recommend that adults should exercise for 20 - 60 min on 3 - 5 days.week(-1 ) ( M.L. Pollock , et al. , The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness , and flexibility in healthy adults . Medicine and Science in Sports and Exercise , 30 ( 6 ) ( 1998 ) 975 - 991 . ) . For individuals constrained by a busy lifestyle , an exercise prescription that delivers benefits with the minimum investment of time is attractive . The purpose of the present study , therefore , was to examine the effect of instructing sedentary individuals to undertake 20 min of brisk walking , in two different patterns , 3 days per week , on fitness and other cardiovascular disease ( CVD ) risk factors . METHODS Forty-eight subjects ( 31 women ) mean ( + /-SD ) age 45.7 + /- 9.4 year were r and omly assigned to either one 20-min walk ( single bout ) , two 10-min walks ( accumulated bouts ) 3 days week(-1 ) for 12-week , or no training ( control ) . Oxygen consumption ( VO2 ) , heart rate ( HR ) , and ratings of perceived exertion ( RPE ) were measured during a 4-stage treadmill test at pre- and post-intervention . Body composition , resting blood pressure and fasting lipoproteins were also assessed . Thirty-two subjects completed the study . RESULTS There was a significant difference between single-bout and accumulated-bout walkers in the reduction of HR at stages 2 and 3 of the treadmill test from pre- to post-intervention ( P < 0.05 ) . There were no differences between groups for changes in VO2 or RPE from pre- to post-intervention . There were also no changes in body mass , adiposity , blood pressure , waist and hip circumferences , or lipid/lipoproteins . CONCLUSION Brisk walking for 20 min on 3 days of the week fails to alter cardiovascular disease risk factors in previously sedentary adults Background / objectives : Although several studies have reported associations between moderate to vigorous physical activity ( MVPA ) , body fatness and visceral adipose tissue ( VAT ) , the extent to which associations differ among Latinos and non-Latinos remains unclear . This study evaluated the associations between body composition and MVPA in Latino and non-Latino adults . Subjects/ methods : An exploratory , cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month r and omized controlled trial that tested the efficacy of text messaging  to improve  weight loss . MVPA , body fatness and VAT were assessed by waist-worn accelerometry , dual-energy x-ray absorptiometry ( DXA ) , and DXA-derived software ( GE CoreScan GE , Madison , WI , USA ) , respectively . Participants with < 5 days of accelerometry data or missing DXA data were excluded ; 236 participants had complete data . Multivariable linear regression assessed associations between body composition and MVPA per day , defined as time in MVPA , bouts of MVPA ( time per bout ⩾10 min ) , non-bouts of MVPA ( time per bout < 10 min ) and meeting the 150-min MVPA guideline . The modifying influence of ethnicity was modeled with a multiplicative interaction term . Results : The interaction between ethnicity and MVPA in predicting percent body fat was significant ( P=0.01 , 95 % confidence interval ( CI ) ( 0.58 , 4.43 ) ) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared with Latinos ( adjusted for age , sex and accelerometer wear time ) . There was no interaction between ethnicity and MVPA in predicting VAT ( g ) ( P=0.78 , 95 % CI ( −205.74 , 273.17 ) ) and body mass index ( BMI ) ( P=0.18 , 95 % CI ( −0.49 , 2.26 ) ) . Conclusions : An increase in MVPA was associated with a larger decrease in body fat , but neither BMI nor VAT , in non-Latinos compared with Latinos . This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness The aim of this study was to determine whether accumulated short bouts of exercise can achieve the same cardiovascular benefits as a single long bout of exercise in sedentary male Japanese workers and to compare the programs ’ relative effects on oxidative stress . Twenty-three sedentary male workers were r and omly assigned into 2 different exercise programs : a Long-bout group , which performed a single period of continuous exercise ( Long-bout group : 30 min × 1 ) 3 d per week , and a Short-bouts group , which performed 3 short bouts of exercise ( Short-bouts group : 10 min × 3 ) 3 d per week . Cardiovascular risk factors , including the plasma thiobarbituric acid-reactive substances ( TBARS ) level , were examined at baseline and after both 10 and 20 wk . In the Long-bout group , waist circumference and maximum oxygen uptake ( VO2max ) significantly improved after 20 wk . The Short-bouts group demonstrated significant increases in VO2max after 10 weeks and in HDL-C after 20 wk . Plasma TBARS significantly decreased after 20 weeks in the Long-bout group and tended to decrease ( but not significantly ) in the Short-bouts group . These results indicate that accumulated short bouts of exercise are an effective option , especially for busy workers , for incorporating exercise into one ’s lifestyle Objective : The specific aim of this study was to determine if three 10 minute bouts of exercise per day ( 3 × 10 ) and two 15 minute bouts per day ( 2 × 15 ) were as effective as one 30 minute bout per day ( 1 × 30 ) for improving VO2 max and weight loss . Methods : Overweight , female college students ( body mass index ≥28 kg/m2 ) were recruited and assessed at baseline and post-treatment for aerobic fitness ( Astr and maximal cycle test ) , weight , skinfold thickness ( 7-site ) , and circumference measures ( 4-site ) . Following measurement of  resting energy expenditure ( REE ) , subjects were asked to follow a self-monitored calorie restricted diet ( 80 % of REE ) for the twelve week duration of the study and were assigned ( non-r and om ) to one of four treatment groups : 1 ) a nonexercising control group ( control , n = 8) , 2 ) a 30 minutes continuous exercise group ( 1 × 30 , n = 12 ) , 3 ) a 30 minutes accumulated exercise group ( 2 × 15 , n = 10 ) and 4 ) a second 30 minutes accumulated exercise group ( 3 × 10 , n = 8) . The exercising subjects participated in aerobic exercise training at 75 % of heart rate reserve three to five days per week with all exercise monitored . Results : VO2 max increased significantly while weight , body mass index , sum of skinfolds , and sum of circumferences decreased significantly from baseline to post-treatment in the 1 × 30 , 2 × 15 and the 3 × 10 groups , but not in the control group . A tertiary finding was that exercise participation did not differ among the exercising groups with regard to the average number of days per week . Conclusions : These results support the hypothesis that exercise accumulated in several short bouts has similar effects as one continuous bout with regard to aerobic fitness and weight loss during caloric restriction in overweight , young women Purpose . The purpose of this study was to test if moderate to vigorous physical activity ( MVPA ) in less than the recommended ≥ 10-minute bouts related to weight outcomes . Design . Secondary data analysis . Setting . R and om sample from the U.S. civilian noninstitutionalized population included in the National Health and Nutrition Examination Survey ( NHANES ) . Participants . A total of 4511 adults aged 18 to 64 years from the 2003–2006 NHANES . Method . Clinical ly measured body mass index ( BMI ) and overweight/obese status were regressed on accelerometer measures of minutes per day in higher-intensity long bouts ( ≥ 10 minutes , ≥ 2020 accelerometer counts per minute [ cpm ] ) , higher-intensity short bouts ( < 10 minutes , ≥ 2020 cpm ) , lower-intensity long bouts ( ≥ 10 minutes , 760–2019 cpm ) , and lower-intensity short bouts ( < 10 minutes , 760–2019 cpm ) . Socioeconomic and demographic characteristics were controlled . Results . Both higher-intensity short bouts and long bouts of PA  related to lower BMI and risk of overweight/obesity . Neither lower-intensity short bouts nor long bouts related to BMI or risk of overweight/obesity Conclusion . The current ≥ 10-minute MVPA bouts guideline was based on health benefits other than weight outcomes . Our findings showed that for weight gain prevention , accumulated higher-intensity PA bouts of < 10 minutes are highly beneficial , supporting the public health promotion message that “ every minute counts . This study sought to determine whether a 12-week intermittent ( INT ; 2 3 15 min·d−1 ) exercise program yielded similar improvements in cardiovascular health and fitness , compared with a traditional 12-week , 30-minute continuous ( CON ; 1 X 30 min·d−1 ) exercise program . A second purpose was to determine the effects of switching exercise programs and continuing training for an additional 12 weeks . Twenty women and 17 men , ( age 48.8 ± 9.0 years ) were divided r and omly into 2 groups : INT ( n = 20 ) and CON ( n = 17 ) . Aerobic exercise was performed 4 d·wk−1 for 12 weeks . Subjects then crossed over to the opposite training program for an additional 12 weeks of training . Subjects exercised incrementally for weeks 1–4 and training was conducted at 70–80 % heart rate reserve for weeks 5–24 . Both groups showed comparable exercise adherence , completing 96.6 ± 12.2 % ( CON ) and 96.3 % ± 17.7 % ( INT ) of the prescribed exercise time . The INT walked at a lower percentage of & OV0312;O2max , maximum heart rate , systolic blood pressure , and diastolic blood pressure ( p < 0.05 ) . Maximal oxygen consumption increased by 4.5 % in CON and by 8.7 % in INT . Following the second 12 weeks , & OV0312;O2max increased by 3.6 and 7.7 % in CON and INT , respectively . Treadmill test time increased by 41 seconds in CON ( p < 0.05 ) and 71 seconds in INT ( p < 0.05 ) after 12 weeks of training . High-density lipoproteins significantly increased in the INT group following the first 12 weeks of training . This study suggests that an INT exercise program , which is incremental in nature , provides comparable , and in some cases greater , health and fitness benefits than those expected following traditional CON exercise training We compared the effects of one vs two daily bouts of walking on aerobic fitness and body composition in postmenopausal women . One hundred and thirty-four subjects were r and omized into exercise groups or a control group and 130 completed the study . The subjects walked 5 d/week for 15 weeks at 65 % of their maximal aerobic power expending 300 kcal ( 1255 kJ ) in exercise in one ( Group S1 ) or two daily sessions ( Group S2 ) . VO(2max ) was measured in a direct maximal treadmill test . Body mass index ( BMI ) was calculated and the percentage of body fat ( fat% ) estimated using skinfold measurements . The net change in the VO(2max ) was 2.5 mL min/kg ( 95 % CI 1.5 , 3.5 ) ( 8.7 % ) in Group S1 and 2.5 mL min/kg ( 95 % CI 1.5 , 3.5 ) ( 8.8 % ) in Group S2 . The net change in body mass was -1.2 kg ( 95 % CI-1.9 , -0.5 ) in Group S1 and -1.1 kg ( 95 % CI -1.8 , -0.4 ) in Group S2 . The net fat% change was -2.1 % ( 95 % CI-2.7 , -1.4 ) in Group S1 and -1.7 % ( 95 % CI-2.3 , -1.0 ) in Group S2 . Exercise improved the maximal aerobic power and body composition equally when walking was performed in one or two daily bouts CONTEXT Enhancing participation in long-term exercise may translate into improved long-term weight loss  in overweight adults . OBJECTIVES To compare the effects of intermittent with traditional continuous exercise on weight loss , adherence , and fitness , and to examine the effect of combining intermittent exercise with that using home exercise equipment . DESIGN R and omized trial from September 1996 through September 1998 . SETTING AND PARTICIPANTS A total of 148 sedentary , overweight ( mean [ SD ] body mass index , 32.8 [ 4.0 ] kg/m2 ) women ( mean [ SD ] age , 36.7 [ 5.6 ] years ) in a university-based weight control program . INTERVENTIONS Eighteen-month behavioral weight control program with 3 groups : long-bout exercise ( LB ) , multiple short-bout exercise ( SB ) , or multiple short-bout exercise with home exercise equipment ( SBEQ ) using a treadmill . MAIN OUTCOME MEASURES Body weight , body composition , cardiorespiratory fitness , and exercise adherence . RESULTS Of 148 subjects , 115 ( 78 % ) completed the 18-month program . At 18 months , mean ( SD ) weight loss was significantly greater in subjects in the SBEQ group compared with subjects in the SB group ( -7.4 [ 7.8 ] kg vs -3.7 [ 6.6 ] kg ; P<.05 ) . Mean ( SD ) weight loss for subjects in the LB group ( -5.8 [ 7.1 ] kg ) was not significantly different than for subjects in the SB or SBEQ groups . Subjects in the SBEQ group maintained a higher level of exercise than subjects in both the SB and LB groups ( P<.05 ) at 13 to 18 months of treatment . All groups showed an increase in cardiorespiratory fitness from baseline to 18 months , with no difference between groups . Mean ( SD ) weight loss at 18 months was significantly greater in individuals exercising more than 200 min/wk throughout the intervention ( -13.1 [ 8.0 ] kg ) compared with individuals exercising 150 to 200 min/wk ( -8.5 [ 5.8 ] kg ) or less than 150 min/wk ( -3.5 [ 6.5 ] kg ) ( P<.05 ) . CONCLUSIONS Compared with the LB group , subjects in the SB group did not experience improved long-term weight loss , exercise participation , or cardiorespiratory fitness . Access to home exercise equipment facilitated the maintenance of SB , which may improve long-term weight loss . A dose-response relationship exists between amount of exercise and long-term  weight loss  in overweight adult women OBJECTIVE To investigate whether prescribing exercise in several short-bouts versus one long-bout per day would enhance exercise adherence , cardiorespiratory fitness , and weight loss in overweight adult females in a behavioral weight control program . DESIGN R and omized controlled trial with subjects r and omized to either a short-bout exercise group ( SB , n = 28 , age = 40.4 + /- 5.9 yrs ) or a long-bout exercise group ( LB , n = 28 , age = 40.9 + /- 7.3 yrs ) , with subjects followed for a period of 20 weeks . Both groups were instructed to exercise 5 days per week with exercise duration progressing from 20 to 40 min per day . The LB group performed one exercise bout per day , whereas the SB group performed multiple 10 min bouts of exercise per day . The recommended caloric intake for all subjects was 5022 - 6277 kJ/day ( 1200 - 1500 kcal/day ) , with fat reduced to 20 % of caloric intake . SUBJECTS Fifty-six obese , sedentary females ( BMI = 33.9 + /- 4.1 kg/m2 ) . MEASUREMENTS Exercise participation was assessed from self-reported diaries and Tri-Trac Accelerometers . Cardiorespiratory fitness was assessed using a submaximal cycle ergometer test . RESULTS Exercising in multiple short-bouts per day improved adherence to exercise : the SB group reported  exercising on a greater number of days ( mean + /- s.d . = 87.3 + /- 29.5 days vs 69.1 + /- 28.9 days ; P < 0.05 ) and for a greater total duration ( 223.8 + /- 69.5 min/week vs 188.2 + /- 58.4 min/week ; P = 0.08 ) than the LB group . Predicted VO2Peak increased by 5.6 % and 5.0 % for the LB and SB groups , respectively ( P < 0.05 ) . There was a trend for the weight loss to be greater in the SB group ( -8.9 + /- 5.3 kg ) compared to the LB group ( -6.4 + /- 4.5 kg ; P < 0.07 ) . CONCLUSION These results suggest that short-bouts of exercise may enhance exercise adherence .  Short-bouts of exercise may also enhance weight loss and produce similar changes in cardiorespiratory fitness when compared to long-bouts of exercise . Thus , short-bouts of exercise may be preferred when prescribing exercise to obese adults We studied the fractionization of walking training and search ed for the minimum dose to affect coronary risk factors in two r and omized controlled trials . Altogether 134 ( Study I ) and 121 ( Study II ) healthy , sedentary postmenopausal women started the trials , and 130 ( Study I ) and 116 ( Study II ) completed them . In Study I the exercise intensity was 65 % of the maximal aerobic power ( VO2max ) and a total of 300 kcal was expended in one ( Group W1 ) or two ( Group W2 ) daily walking bouts . In Study II the exercise was continuous , and the exercise intensity ( % of VO2max ) and energy expenditure ( kcal session(-1 ) ) were 55 % and 300 kcal ( Group W3 ) , 45 % and 300 kcal ( Group W4 ) , 55 % and 200 kcal ( Group W5 ) and 45 % and 200 kcal ( Group W6 ) . All the subjects walked 5 days a week . The outcome measures were blood pressure , serum lipoproteins and blood glucose and plasma insulin in fasting state and also during 2-h oral glucose tolerance test in Study I. There was no change in diastolic pressure in the original study groups , but in the combined exercise group ( W1+W2 ) in Study I , the mean diastolic pressure declined by -3.0 mmHg ( 95 % con-fidence interval ( CI ) -5.5 to -0.4 ) ( P=0.025 ) in comparison with that of the controls . The mean blood glucose declined by -0.21 mmol L(-1 ) ( CI -0.33 to -0.09 ) in Group W1 and -0.13 mmol L(-1 ) ( CI -0.25 to -0.01 ) in Group W2 compared to controls ( P=0.03 ) . Also the 2-h glucose concentration decreased in Groups W1 and W2 compared to controls . Systolic blood pressure , serum lipoproteins and insulin levels did not change in Study I or Study II . We conclude that our training program with the greatest exercise dose , exercise intensity 65 % of VO2max and weekly expenditure of 1500 kcal had a minimal , positive effect on diastolic pressure and blood glucose , and the effect was similar in one or two daily exercise session groups . This exercise dose is probably close to the minimum to affect coronary risk factors in healthy postmenopausal women . To get a more pronounced and clinical ly relevant effect , a greater exercise dose is needed
target: Conclusions The current evidence , from cross-sectional and prospect i ve cohort studies , supports that physical activity of any bout duration is associated with improved health outcomes , which includes all-cause mortality .
background: Purpose This study aim ed to conduct a systematic literature review to determine whether physical activity episodes of < 10 min in duration have health-related benefits or , alternatively , if the benefits are only realized when the duration of physical activity episodes is ≥10 min .