BMI change and leisure time physical activity (LTPA): an 11-y follow-up study in apparently healthy men aged 20–69 y with normal weight at baseline

The Association of Menstruation and Leisure-Time Physical Activity among Korean Female University Students: A Preliminary Study

An active lifestyle elicits many health benefits. This study’s aim is to understand the actual of leisure time physical activity (LTPA) of female university students in Korea who are experiencing stress due to, e.g., study and employment. LTPA is the degree of exercise participation in leisure time; it is cardiovascular and strength-based behavior occurring within recreation, exercise or sport and provides a positive effect on life satisfaction and psychological well-being. LTPA has been recommended as a method of reducing menstrual symptom severity. However, a lack of evidence exists to support a clear relationship between LTPA and menstruation in female university students. Health consciousness (HC) refers to the degree of interest in one’s health, and Korean female university students pay considerable attention to their body shape, diet habits, and LTPA. This study investigated female university students (K University in Gangwon-do, D University in Busan, and U University in Ulsan) in three metropolitan cities in Korea. Specifically, after seeking cooperation from the person in charge of each university, the purpose of this study was explained. In addition, after promising to provide coffee coupons to students who wish to respond to the survey, cooperation was sought in recruiting research subjects through the person in charge of each university. In addition, a total of 36 surveys that did not have contents filled in fully or gave inconsistent answers were excluded among all survey participants. Chi-square test, t-test and univariate one-way ANOVA, and Pearson’s correlation coefficient analysis were performed for between groups (HC, LTPA, intention to participate in LTPA). The LTPA results in relation to the menstruation patterns of Korean female college students are shown. First, there were no significant differences between menstruation (regular vs. irregular) and general LTPA during non-menstrual time periods (χ2 = 5.828, p < 0.212). However, female university students with regular menstruation patterns had higher LTPA after menstruation compared to female university students with irregular menstruation. Second, there were significant differences in the relationships among HC (p = 0.000), amount of LTPA (p = 0.002), and intention to perform LTPA (p = 0.002), according to the menstruation patterns (regular vs. irregular) of Korean female university students. In other words, those with regular menstruation patterns showed higher HC, amount of LTPA and intention to participate in LTPA than those with irregular menstruations. Third, there were significant differences in the relationship among HC (p = 0.000), amount of LTPA (p = 0.000), and intention to participate in LTPA (p = 0.000) according to LTPA of Korean female university students. Causation cannot be inferred from correlational studies. Therefore, female university students ultimately have different HC and participation in LTPA depending on menstruation regularity.

Comparison of General Dietary and Lifestyle Habits Before and During COVID-19 among the Saudi Adult Population in Riyadh

Background:

During the initial outbreak of the global COVID-19 pandemic, there were few effective evidence-based vaccines or treatments available, which led to many attempts to find alternative options.

Objective:

This study aimed to compare the general dietary and lifestyle habits among the Saudi adult population in Riyadh before and during COVID-19.

Methods:

This was a cross-sectional study targeting the Riyadh population from 16 May 2020 to 16 June 2020. The study was composed of a structured questionnaire that collected demographic information (such as age, gender, place of residence, and health status), dietary habit information (such as daily intake of certain foods, food frequency, number of meals/day, and number of times drinking tea and coffee), lifestyle habit information (such as physical activity; sleep quality; and time spent using the internet, social media, and electronic devices for fun or stress relief) using Google forms. A total of 1193 participants aged over 18 years were included in the study.

Results:

During the COVID-19 period, a significant increase was observed in the number of meals eaten daily, fruit and vegetable intake, the intake of sweets and cakes/biscuits, the number of hours of sleep per day, and time spent on the internet and social media compared with the pre- COVID-19 pandemic period. However, the amount of running exercise or physical activity was found to be significantly reduced.

Conclusion:

In this study, we found that the dietary and lifestyle habits changed among Saudi adults during the COVID-19 period. Similar large-scale studies should be undertaken in the future to confirm the results of the study.

Concurrent changes in physical activity and body mass index among 66 852 public sector employees over a 16-year follow-up: multitrajectory analysis of a cohort study in Finland

OBJECTIVES

To identify concurrent developmental trajectories of physical activity and body mass index (BMI) over time.

DESIGN

Prospective cohort study, repeated survey.

SETTING

Cohort study in Finland.

PARTICIPANTS

66 852 public sector employees, who have been followed up for 16 years.

OUTCOME MEASURES

Shapes of trajectories of changes in physical activity and BMI.

RESULTS

At baseline, mean age was 44.7 (SD 9.4) years, BMI 25.1 (SD 4.1) kg/m² and physical activity 27.7 (SD 24.8) MET hours/week. Four clusters of concurrent BMI and physical activity trajectories were identified: (1) normal weight (BMI <25 kg/m²) and high level of physical activity (30-35 MET hours/week), (2) overweight (BMI 25-30 kg/m²) and moderately high level of physical activity (25-30 MET hours/week), (3) obesity (BMI 30-35 kg/m²) and moderately low level of physical activity (20-25 MET hours/week) and (4) severe obesity (BMI >35 kg/m²) and low level of physical activity (<20 MET hours/week). In general, BMI increased and physical activity decreased during the follow-up. Decline in physical activity and increase in BMI were steeper among obese respondents with low level of physical activity.

CONCLUSIONS

Changes in BMI and physical activity might be interconnected. The results may be of interest for both clinicians and other stakeholders with respect to informing measures targeting increasing physical activity and controlling weight, especially among middle-aged people. Additionally, the information on the established trajectories may give individuals motivation to change their health behaviour.

Changes in leisure time physical activity unrelated to subsequent body weight changes, but body weight changes predicted future activity

Physical activity and obesity are known to be associated. We investigated whether a change in leisure time physical activities (LTPA) predicts a subsequent weight change, or vice versa.We used data from a longitudinal study among Danish adults surveyed in 1983-1984, 1987-1988, and 1993-1994. Between two sequential surveys, the change in LTPA was grouped as no change, became less or more active; the change in body weight was defined as no change, lost or gained of more than one body mass index (BMI) unit.Among 2386 adults, change in LTPA was not associated with subsequent weight change. However, a loss in body weight (BMI change < -1 unit) was associated with subsequent either becoming less [OR = 1.49, 95% CI (1.03-2.15)] or borderline more active [OR = 1.37, 95% CI (0.99-1.90)]. Subgroup analyses showed particularity among females that a loss in body weight was associated with subsequent becoming more active [OR = 1.83, 95% CI (1.15-2.89)].Our results suggest that change in LTPA is unrelated to subsequent weight change, but loss in body weight seems related to subsequent more active among female adults.

Leisure Time Physical Activity and Associated Factors among Adults in Estonia 2000-2018

In order to implement evidence-based strategies, there is a need to assess (1) time trend in leisure time physical activity (LTPA) and (2) the relationship between trend of LTPA and trend of potential explanatory factors in Estonia from 2000 to 2018. Data from 25−64-year-old adults (n = 16,903) were drawn from cross-sectional surveys of Health Behavior among Estonian Adult Population. Joinpoint regression analysis was used to calculate annual percentage changes (APCs) and to identify whether there was a significant change in trends of LTPA. Logistic regression analysis was used to assess associations of LTPA with socioeconomic, health-related and health-behavioral factors. Prevalence of LTPA increased from 26.2% to 44.1% among men and from 28.0% to 40.6% among women from 2000 to 2018 (p < 0.001). Average APC for men was 3.4% (95% CI 2.6−4.3) and for women 2.4% (95% CI 1.4−3.4). Adjusted logistic regression model showed that LTPA was statistically significantly associated with higher education and income, economic inactivity, at-least-good self-rated health (SRH) and non-smoking. Interaction of SRH with study year was significant indicating that the association of at-least-good SRH changed over time (p = 0.016). Health promotion activities should be addressed in particular to adults with lower levels of LTPA, paying attention to the factors associated with LTPA.

Associations of physical activity at work and household income with obesity: a cross-sectional study among rural adults in Korea

OBJECTIVES

This study was performed to identify the effect of physical activity at work on obesity and to analyze the contribution of socioeconomic factors and health behaviors to this association, which has been relatively little studied.

METHODS

From the Korean National Cancer Center Community Cohort, a total of 5,587 adults (2,125 men; 3,462 women) aged more than 30 years living in rural areas were enrolled. Information on socio-demographic factors, health behaviors, and body mass index was gathered using face-to-face interviews and measurements of height and weight.

RESULTS

Inverse associations were identified between vigorous-intensity physical activity at work and obesity in both men and women, while no association was found between vigorous-intensity physical activity during leisure time and obesity. High household income was independently associated with a lower risk of obesity among those who had low levels of vigorous-intensity physical activity at work. Vigorous physical activity at work showed an inverse association with obesity in rural areas where heavy manual labor is common.

CONCLUSIONS

Our findings indicate the necessity to account for various types of physical activity to improve the assessment and prevention of obesity.

Sedentary time, physical activity, and adiposity in a longitudinal cohort of nonobese young adults

Background

Young adulthood is a critical period for excessive weight gain. The extent to which young adults' sedentary time (ST) and moderate-to-vigorous physical activity (MVPA) relate to adiposity and weight gain remains unclear.

Objective

The purpose of this study was to examine the relation of ST and MVPA with adiposity and change in adiposity in healthy, nonobese young adults over a 2-y period.

Design

Participants were 71 adults aged 20-35 y. Measurements included ST and MVPA by accelerometry and reported energy intake at baseline, and anthropometry (%FM) and fat mass (FM) by dual-energy X-ray absorptiometry at baseline, year 1, and year 2. Associations of baseline ST and MVPA with adiposity were examined with the use of repeated-measures linear regression models, controlling for age, sex, and reported energy intake. The Benjamini-Hochberg procedure was used to adjust for multiple comparisons.

Results

Participants [mean ± SD body mass index (BMI; kg/m2): 22.6 ± 2.4] engaged in 8.5 ± 1.5 h ST/d and 0.4 ± 0.3 h MVPA/d. At baseline, adults who engaged in ST for ≥8 h/d had higher FM, %FM, and lower MVPA, whereas those who engaged in MVPA for ≥30 min/d had lower FM and %FM. In fully adjusted models, ST was significantly associated with baseline body weight, hip circumference, BMI, FM, and %FM and with year-1 body weight, waist and hip circumference, FM, and %FM, but not with any year-2 adiposity indicators. MVPA was not significantly associated with any adiposity indicators at baseline, year 1, or year 2 in fully adjusted models. Over 2 y, participants significantly increased waist circumference, BMI, FM, and %FM (all P-values <0.05), but there were no associations among baseline ST and MVPA with change in adiposity.

Conclusions

Among nonobese young adults, high ST and low MVPA were related to elevated adiposity but did not predict change in adiposity over time. This trial was registered at clinicaltrials.gov as NCT00945633.

Physical Activity and Obesity: Their Interaction and Implications for Disease Risk and the Role of Physical Activity in Healthy Weight Management

The prevalence of overweight and obesity is increasing at an epidemic rate. Increased adiposity, especially central or visceral adiposity, is predictive of cardiovascular disease/coronary heart disease, metabolic syndrome, and type 2 diabetes mellitus. The increased risk for cardiovascular disease/coronary heart disease and metabolic abnormalities associated with abdominal obesity may be mediated, at least in part, by increased systemic inflammation. Greater physical activity and/or fitness may reduce inflammation associated with greater visceral adiposity. Increased adiposity and low levels of physical activity and/or fitness are risk factors for atherosclerotic disease and type 2 diabetes, as well as the increased mortality associated with them. Increased physical activity/fitness reduces disease and mortality risk regardless of body mass index but does not completely abrogate the risks associated with obesity. Both moderate to vigorous physical activity and weight loss independently reduce the risk for type 2 diabetes and improve glucose/insulin metabolism via di ferent mechanisms. Physical activity on the order of 2500 to 2800 kcal/wk may be necessary to prevent weight gain or maintain weight loss. Strength training is recommended as an adjunct to regular aerobic exercise but not as the primary mode of exercise for weight loss. Individuals are strongly encouraged to engage in regular physical activity because of the known health benefits, regardless of whether that activity results in weight loss.

Physical activity and dietary intake in BMI discordant identical twins

OBJECTIVE

Despite the latest discovery of obesity-associated genes, the rapid rise in global obesity suggests a major role for environmental factors. This study investigated the influence of environmental factors on physical activity and dietary intake independent of genetic effects.

METHODS

Sixteen female monozygotic twins aged 48.8 ± 9.8 years (range 37-70) with a mean BMI discordance of 3.96 ± 2.1 kg/m(2) (range 0.7-8.2) were studied. Physical activity was determined using 7-day accelerometry and dietary intake using 3-day 24-h recalls.

RESULTS

Heavier cotwins were generally less physically active (mean activity counts × 1,000 per day ± SD; 505.5 ± 155.1 vs. 579.6 ± 185.4, P = 0.047) and tended to spend 6.1 min/day less in moderate to vigorous physical activity than leaner cotwins (P = 0.09). Energy intake did not significantly differ within pairs. Total fat intake (en%; P = 0.03), specifically monounsaturated fat (P < 0.01) and polyunsaturated fat (P = 0.08), was higher in the heavier cotwins.

CONCLUSIONS

After eliminating genetic effects, higher BMI is associated with lower overall and moderate to vigorous physical activity and higher intake of total fat, although the direction of causality cannot be determined. Future identification of the environmental factors responsible for these findings might contribute to developing new strategies in managing obesity.

The relationships of self-efficacy, physical activity, and paid work to health-related quality of life among patients with chronic obstructive pulmonary disease (COPD)

Purpose

Although chronic obstructive pulmonary disease (COPD) primarily affects the lungs, it is regarded as a systemic disorder associated with comorbidity and physical deterioration, which often results in reduced levels of health-related quality of life (HRQoL). Self-efficacy is an important concept in self-management, which is vital for improving HRQoL in patients with COPD. The purpose of this study was to examine how general self-efficacy, leisure time physical activity, and sociodemographic variables such as employment status are related to the physical and mental health components of HRQoL in patients with COPD.

Patients and methods

In this cross-sectional study, 97 COPD patients (54.6% male, mean age 64.6 years, standard deviation [SD] 9.5) beginning a pulmonary rehabilitation program completed three self-report questionnaires: the short form (SF)-12v2 Health Survey as a measure of HRQoL; the General Self-Efficacy Scale; and a standardized instrument measuring regular leisure time physical activity.

Results

The physical health component median score was 31.3 (interquartile range [IQR] 16.3) and the mental health component median score was 45.9 (IQR 21.5). Two sets of linear regression analyses were performed, one predicting physical health and the other predicting mental health. The first analysis showed that better physical health was directly related to being in paid work (P-value <0.001), but was not significantly related to age, sex, marital status, education, work status, physical activity, or self-efficacy. In the second analysis, better mental health was directly related to living with a partner, being physically active, and having higher self-efficacy (P-value <0.001).

Conclusion

The findings suggest that general self-efficacy has differential relationships to the two dimensions of HRQoL. Our results indicate that general self-efficacy, physical activity, and paid work might be important factors for improving HRQoL of persons with COPD, and should be taken into consideration in pulmonary rehabilitation.

Obesity increases risk of declining physical activity over time in women: a prospective cohort study

OBJECTIVE

Research indicates that risk of obesity increases as physical activity (PA) decreases; however, the reciprocal effect has been rarely studied. The present investigation was conducted to determine the contribution of obesity on objectively measured PA over 20 months.

DESIGN AND METHODS

A prospective cohort design with 254 middle-aged women was employed. Body fat percentage (BF%) was measured using Bod Pod, and obesity was defined as BF% ≥32%. PA was assessed objectively using 7-day accelerometry at baseline and ∼20 months later at follow-up.

RESULTS

Of the 254 subjects, 124 were obese (49%) at baseline. Mean BF% was 32.1 ± 7.8 and average age was 41.7 ± 3.1 years. Mean weekly PA was 2.79 ± 0.85 million activity counts for all participants. Over the 20-month period, PA decreased significantly more in obese women (-8.1% ± 27.1%) than in nonobese women (0.3% ± 31.7%) after adjusting for confounders (F = 5.3, P = 0.022). Moderate plus vigorous PA levels also decreased more in obese women (-28.1 ± 73.6 min/week) than in nonobese women (-5.9 ± 66.8 min/week), after adjusting for covariates (F = 7.84; P = 0.0055).

CONCLUSIONS

It appears that obese women tend to reduce PA over time at a faster rate than nonobese women. Evidently, obesity is a risk factor for decreasing PA over time in middle-aged women.

45-Year trends in women's use of time and household management energy expenditure

CONTEXT

Relationships between socio-environmental factors and obesity are poorly understood due to a dearth of longitudinal population-level research. The objective of this analysis was to examine 45-year trends in time-use, household management (HM) and energy expenditure in women.

DESIGN AND PARTICIPANTS

Using national time-use data from women 19-64 years of age, we quantified time allocation and household management energy expenditure (HMEE) from 1965 to 2010. HM was defined as the sum of time spent in food preparation, post-meal cleaning activities (e.g., dish-washing), clothing maintenance (e.g., laundry), and general housework. HMEE was calculated using body weights from national surveys and metabolic equivalents.

RESULTS

The time allocated to HM by women (19-64 yrs) decreased from 25.7 hr/week in 1965 to 13.3 hr/week in 2010 (P<0.001), with non-employed women decreasing by 16.6 hr/week and employed women by 6.7 hr/week (P<0.001). HMEE for non-employed women decreased 42% from 25.1 Mj/week (6004 kilocalories per week) in 1965 to 14.6 Mj/week (3486 kcal/week) in 2010, a decrement of 10.5 Mj/week or 1.5 Mj/day (2518 kcal/week; 360 kcal/day) (P<0.001), whereas employed women demonstrated a 30% decrement of 3.9 Mj/week, 0.55 Mj/day (923 kcal/week, 132 kcal/day) (P<0.001). The time women spent in screen-based media use increased from 8.3 hr/week in 1965 to 16.5 hr/week in 2010 (P<0.001), with non-employed women increasing 9.6 hr/week and employed women 7.5 hr/week (P<0.001).

CONCLUSIONS

From 1965 to 2010, there was a large and significant decrease in the time allocated to HM. By 2010, women allocated 25% more time to screen-based media use than HM (i.e., cooking, cleaning, and laundry combined). The reallocation of time from active pursuits (i.e., housework) to sedentary pastimes (e.g., watching TV) has important health consequences. These results suggest that the decrement in HMEE may have contributed to the increasing prevalence of obesity in women during the last five decades.

Patterns of objectively measured physical activity in normal weight, overweight, and obese individuals (20-85 years): a cross-sectional study

BACKGROUND

The magnitude of the association between physical activity (PA) and obesity has been difficult to establish using questionnaires. The aim of the study was to evaluate patterns of PA across BMI-defined weight categories and to examine the independent contribution of PA on weight status, using accelerometers.

METHODS

The study was a cross-sectional population-based study of 3,867 adults and older people aged 20-85 years, living in Norway. PA was assessed for seven consecutive days using the ActiGraph GT1M accelerometer. Anthropometrical data was self-reported and overweight and obesity was defined as having a body mass index (BMI) of 25-<30 and ≥30 kg/m(2), respectively.

RESULTS

Overweight and obese participants performed less overall PA and PA of at least moderate intensity and took fewer steps, compared to normal weight participants. Although overall PA did not differ between weekdays and weekends, an interaction between BMI category and type of day was present, indicating a larger difference in overall PA between BMI categories on weekends compared to weekdays. Obese participants displayed 19% and 25% lower overall physical activity compared to normal weight participants, on weekdays and weekends, respectively. Participants in the most active quintile of overall PA had a 53% lower risk (OR 0.47, 95% CI: 0.37 to 0.60) for having a BMI above or below 25 kg/m(2), and a 71% lower risk (OR: 0.29, 95% CI: 0.20 to 0.44) for having a BMI above or below 30 kg/m(2).

CONCLUSIONS

Overweight and obese participants engaged in less overall PA and moderate and vigorous PA compared with normal weight individuals. The weight related differences in overall PA were most pronounced on the weekend and the risk of being overweight or obese decreases across quintiles of PA.

Etiology of overactive bladder: a diet and lifestyle model for diabetes and obesity in older women

OBJECTIVE

To evaluate a coherent, evidence-based hypothesis that specific modifiable lifestyle factors implicated in the development of diabetes and associated obesity are related to the onset of OAB.

METHODS

A hypothetical causative model for OAB involving modifiable lifestyle factors implicated in the development of diabetes and obesity was constructed, based on a systematic literature review. Secondary analysis of data was undertaken in a prospective cohort of women aged 40 and over, living in Leicestershire, UK. Subjects included 3,411 women free from OAB at baseline and 277 incident cases of OAB. Reported diet, lifestyle, morbid, and social factors were measured at baseline and incident cases at 1-year follow-up. Graphical chain modeling was used to estimate the associations between variables and identify likely pathways involved.

RESULTS

All hypothesized lifestyle factors (physical activity, high glycemic index, and high energy intake) plus diabetes and obesity were retained within the graph as potential contributors. However, low physical activity was the only direct risk factor linked prospectively to the onset of OAB (RR 2.47; 95% CI 1.82, 3.36), in addition to older age.

CONCLUSIONS

Poor lifestyle factors causally linked to diabetes and obesity may contribute to the onset of OAB; low physical activity appears to be an important modifiable causal factor for OAB operating directly as well as indirectly via pathways involving obesity or diabetes. Further research is needed to demonstrate a causal link between lifestyle and OAB.

Maintaining a high physical activity level over 20 years and weight gain

CONTEXT

Data supporting physical activity guidelines to prevent long-term weight gain are sparse, particularly during the period when the highest risk of weight gain occurs.

OBJECTIVE

To evaluate the relationship between habitual activity levels and changes in body mass index (BMI) and waist circumference over 20 years.

DESIGN, SETTING, AND PARTICIPANTS

The Coronary Artery Risk Development in Young Adults (CARDIA) study is a prospective longitudinal study with 20 years of follow-up, 1985-1986 to 2005-2006. Habitual activity was defined as maintaining high, moderate, and low activity levels based on sex-specific tertiles of activity scores at baseline. Participants comprised a population-based multicenter cohort (Chicago, Illinois; Birmingham, Alabama; Minneapolis, Minnesota; and Oakland, California) of 3554 men and women aged 18 to 30 years at baseline.

MAIN OUTCOME MEASURES

Average annual changes in BMI and waist circumference.

RESULTS

Over 20 years, maintaining high levels of activity was associated with smaller gains in BMI and waist circumference compared with low activity levels after adjustment for race, baseline BMI, age, education, cigarette smoking status, alcohol use, and energy intake. Men maintaining high activity gained 2.6 fewer kilograms (0.15 BMI units per year; 95% confidence interval [CI], 0.11-0.18 vs 0.20 in the lower activity group; 95% CI, 0.17-0.23), and women maintaining higher activity gained 6.1 fewer kilograms (0.17 BMI units per year; 95% CI, 0.12-0.21 vs 0.30 in the lower activity group; 95% CI, 0.25-0.34). Men maintaining high activity gained 3.1 fewer centimeters in waist circumference (0.52 cm per year; 95% CI, 0.43-0.61 cm vs 0.67 cm in the lower activity group; 95% CI,0.60-0.75 cm) and women maintaining higher activity gained 3.8 fewer centimeters(0.49 cm per year; 95% CI, 0.39-0.58 cm vs 0.67 cm in the lower activity group; 95% CI, 0.60-0.75 cm) [corrected].

CONCLUSION

Maintaining high activity levels through young adulthood may lessen weight gain as young adults transition to middle age, particularly in women.

Physical activity plays an important role in body weight regulation

Emerging literature highlights the need to incorporate physical activity into every strategy intended to prevent weight gain as well as to maintain weight loss over time. Furthermore, physical activity should be part of any plan to lose weight. The stimulus of exercise provides valuable metabolic adaptations that improve energy and macronutrient balance regulation. A tight coupling between energy intake and energy expenditure has been documented at high levels of physical exercise, suggesting that exercise may improve appetite control. The regular practice of physical activity has also been reported to reduce the risk of stress-induced weight gain. A more personalized approach is recommended when planning exercise programs in a clinical weight loss setting in order to limit the compensatory changes associated to exercise-induced weight loss. With modern environment promoting overeating and sedentary behavior, there is an urgent need for a concerted action including legislative measures to promote healthy active living in order to curb the current epidemic of chronic diseases.

American College of Sports Medicine Position Stand. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults

Overweight and obesity affects more than 66% of the adult population and is associated with a variety of chronic diseases. Weight reduction reduces health risks associated with chronic diseases and is therefore encouraged by major health agencies. Guidelines of the National Heart, Lung, and Blood Institute (NHLBI) encourage a 10% reduction in weight, although considerable literature indicates reduction in health risk with 3% to 5% reduction in weight. Physical activity (PA) is recommended as a component of weight management for prevention of weight gain, for weight loss, and for prevention of weight regain after weight loss. In 2001, the American College of Sports Medicine (ACSM) published a Position Stand that recommended a minimum of 150 min wk(-1) of moderate-intensity PA for overweight and obese adults to improve health; however, 200-300 min wk(-1) was recommended for long-term weight loss. More recent evidence has supported this recommendation and has indicated more PA may be necessary to prevent weight regain after weight loss. To this end, we have reexamined the evidence from 1999 to determine whether there is a level at which PA is effective for prevention of weight gain, for weight loss, and prevention of weight regain. Evidence supports moderate-intensity PA between 150 and 250 min wk(-1) to be effective to prevent weight gain. Moderate-intensity PA between 150 and 250 min wk(-1) will provide only modest weight loss. Greater amounts of PA (>250 min wk(-1)) have been associated with clinically significant weight loss. Moderate-intensity PA between 150 and 250 min wk(-1) will improve weight loss in studies that use moderate diet restriction but not severe diet restriction. Cross-sectional and prospective studies indicate that after weight loss, weight maintenance is improved with PA >250 min wk(-1). However, no evidence from well-designed randomized controlled trials exists to judge the effectiveness of PA for prevention of weight regain after weight loss. Resistance training does not enhance weight loss but may increase fat-free mass and increase loss of fat mass and is associated with reductions in health risk. Existing evidence indicates that endurance PA or resistance training without weight loss improves health risk. There is inadequate evidence to determine whether PA prevents or attenuates detrimental changes in chronic disease risk during weight gain.

Factors associated with BMI change over five years in a Swedish adult population. Results from the Scania Public Health Cohort Study

OBJECTIVES

On account of the increasing worldwide problems associated with overweight and obesity, the aim of the present study was to examine BMI change over 5 years in relation to different lifestyle-, demographic- and psychosocial work-related factors.

METHODS

A cohort of 9913 persons responded to an identical survey in 2000 and 2005. BMI change over the period was examined in relation to gender, age, educational level, physical activity, job strain, and baseline BMI.

RESULTS

Mean BMI as well as prevalence of overweight and obesity increased in the cohort; most among younger persons. In all groups but younger women, BMI increase was greatest in the lowest baseline BMI quartile. Low education was associated with increased BMI at baseline, but not with BMI change over time except among young women. Exercisers had lower BMI than non-exercising persons, and exercise pattern over time was also significantly associated with BMI change. The greatest BMI increase was found among exercise drop-outs, while those who had taken up exercise during the study period were the only group who did not show a significant BMI increase over the study period. Job strain showed inconsistent associations with BMI change.

CONCLUSIONS

Although socioeconomic differences in BMI were observed, these inequalities did not appear to be increasing, except among young women. Persons with a low initial BMI increased more in weight than persons with a high initial BMI. Exercise behaviour appeared to be an important factor for maintaining, or avoiding heavy increase in, BMI.

Incident hypercholesterolemia in relation to changes in vigorous physical activity

PURPOSE

Test whether changes in vigorous exercise affect the risk for hypercholesterolemia.

METHODS

: Incident physician-diagnosed hypercholesterolemia was compared in recreational runners whose weekly distances run increased >0.5 km x d (4034 men, 1897 women), remained constant (+/-0.5 km x d; 4685 men, 1904 women), or decreased >0.5 km x d (15,678 men, 6224 women) during 7.8 yr of prospective follow-up.

RESULTS

Relative to those whose distance was maintained or reduced, the odds ratio (95% confidence interval) for hypercholesterolemia for those whose running increased was significantly less than 1 for men {0.82 (0.72-0.93), P = 0.0006}, women {0.71 (0.54-0.92), P = 0.01}, and men and women combined adjusted for sex {0.80 (0.72-0.89), P < 0.0001}. The significance of the odds ratios was somewhat diminished when adjusted for baseline and follow-up BMI in men {0.89 (0.79-1.01), P = 0.06}, women {0.71 (0.54-0.92), P = 0.08}, and the adjusted sexes combined {0.88 (0.79-0.98), P = 0.02}. When average distance run {i.e., (baseline + follow-up) / 2} was compared with incident hypercholesterolemia in the 6589 runners whose distance remained constant, each kilometer-per-day increment in average running distance was associated with an odds ratio significantly less than 1 in men {0.90 (0.86-0.93)}, women {0.91 (0.84-0.98)}, and the adjusted sexes combined {0.90 (0.87-0.93)}, which was also attributable in part to BMI in men {0.94 (0.90-0.97), P = 0.0005}, women {0.96 (0.89-1.04), P = 0.35}, and the adjusted sexes combined {0.94 (0.91-0.97), P = 0.0003}.

CONCLUSIONS

The odds for hypercholesterolemia 1) decrease in runners who increase their running mileage and 2) decline in association with the higher dose of vigorous activity even in the absence of any change in exercise. These effects are associated in part to the runners' BMI.

Physical inactivity is associated with chronic musculoskeletal complaints 11 years later: results from the Nord-Trøndelag Health Study

Background

Physical inactivity is associated with several diseases, but studies evaluating the association between chronic musculoskeletal complaints (MSCs) and physical exercise have shown conflicting results. The aim of this large-scale prospective population-based study was to investigate the association between self-reported physical exercise at baseline and the prevalence of chronic musculoskeletal complaints (MSCs) 11 years later.

Methods

The results are based upon two consecutive public health studies conducted within the county of Nord-Trøndelag, Norway (The HUNT studies). A total of 39,520 (83%) out of 47,556 adults who participated in HUNT 1 and HUNT 2 responded to questions about physical exercise at baseline in 1984–86, and to questions about musculoskeletal complaints 11 years later (1995–97). Chronic MSCs was defined as MSCs ≥ 3 months during the past year, and chronic widespread MSCs such as pain ≥ 15 days during the last month from the axial region, above the waist, and below the waist. Associations were assessed using multiple logistic regression, estimating prevalence odds ratio (OR) with 95% confidence intervals (CIs). All the final analyses were adjusted for age, gender, body mass index, smoking and education level.

Results

At follow-up 20,223 (51%) reported chronic MSCs, and among these 2,318 (5.9%) reported chronic widespread MSCs. Individuals who exercised at baseline were less likely to report chronic MSCs 11 years later (OR 0.91, 95% CI 0.85–0.97) than inactive persons. Among individuals who exercised more than three times per week, chronic widespread MSCs were 28% less common (OR 0.72, 95% CI 0.59–0.88) compared to inactive individuals.

Conclusion

In this large-scale population-based study, physical exercise was associated with lower prevalence of chronic MSCs, in particular chronic widespread MSCs. Future studies should try to clarify whether chronic MSCs are a cause or a consequence of inactivity.

Changes in physical activity behavior and the development of body mass index during the last 30 years in Norway

Body mass index (BMI; kg/m(2)) has increased markedly in the last decades. We hypothesized that highly physically active persons both at work and at leisure would be resistant to weight gain. The hypothesis was tested by analyzing Norwegian cross-sectional data collected in the period 1972-2002. Participants were 214,449 men and 206,136 women (aged 20-70 years). During the last 30 years in men and the last 15 years in women, a systematic larger BMI increase per year was observed in the sedentary [regression coefficients (SE) in men 0.060 (0.004) kg/m(2) and women 0.137 (0.012) kg/m(2)] compared with highly physically active groups [regression coefficients (SE) in men 0.036 (0.00 4) kg/m(2), and in women -0.001 (0.039) kg/m(2)]. Analyses were robust to adjustments for age, smoking and education. There was a larger absolute net increase in the prevalence of obesity among the sedentary compared with persons performing light, moderate or heavy physical activity (PA) at leisure. PA level in women both at work and in leisure was not associated with weight gain during the last decades. This association was less evident among men. Men and women who were lightly, moderately or highly active at leisure were less likely to be obese compared with those who were sedentary.

Associations between long-term physical activity, waist circumference and weight gain: a 30-year longitudinal twin study

BACKGROUND AND OBJECTIVE

Physical activity level and obesity are both partly determined by genes and childhood environment. To determine the associations between long-term leisure-time physical activity, weight gain and waist circumference and whether these are independent of genes and childhood effects.

DESIGN AND SUBJECTS

The study design is a 30-year follow-up twin study in Finland. For this study, 146 twin pairs were comprehensively identified from the large Finnish Twin Cohort. These twin pairs were discordant for both intensity and volume of leisure physical activity in 1975 and 1981 and were healthy in 1981. At follow-up in 2005, both members of 89 pairs were alive and participated in a structured telephone interview. In the interview self-measured weight and waist circumference, and physical activity level for the whole follow-up were assessed. Paired tests were used in the statistical analyses.

MAIN OUTCOME MEASURES

Waist circumference at 30-year follow-up (2005) and change in weight from 1975 to 2005.

RESULTS

In the 42 twin pairs discordant for physical activity at all time points during the 30-year period, the mean weight gain from 1975 through 2005 was 5.4 kg (95% confidence interval (CI) 2.0-8.9) less in the active compared to inactive co-twins (paired t-test, P=0.003). In 2005, the mean waist circumference was 8.4 cm (95% CI 4.0-12.7) less in the active compared with inactive co-twins (P<0.001). These trends were similar for both monozygotic and dizygotic twin pairs. Pairwise differences in weight gain and waist circumference were not seen in the 47 twin pairs, who were not consistently discordant for physical activity.

CONCLUSION

Persistent participation in leisure-time physical activity is associated with decreased rate of weight gain and with a smaller waist circumference to a clinically significant extent even after partially controlling for genetic liability and childhood environment.

Maintaining vigorous activity attenuates 7-yr weight gain in 8340 runners

INTRODUCTION/PURPOSE

Body weight generally increases with aging in Western societies. Although training studies show that exercise produces acute weight loss, it is unclear whether the long-term maintenance of vigorous exercise attenuates the trajectory of age-related weight gain. Specifically, prior studies have not tested whether the maintenance of physical activity, in the absence of any change in activity, prevents weight gain.

METHODS

Prospective study of 6119 male and 2221 female runners whose running distances changed < 5 km x wk(-1) between baseline and follow-up surveys 7 yr later.

RESULTS

On average, men who maintained modest (0-23 km x wk(-1)), intermediate (24-47 km x wk(-1)), or prolonged running distances (> or = 48 km x wk(-1)) all gained weight through age 64; however, those who maintained > or = 48 km x wk(-1) had one half the average annual weight gain of those who maintained < 24 km x wk(-1). For example, between the ages of 35 and 44 in men and 30 and 39 yr in women, those who maintained < 24 km x wk(-1) gained, on average, 2.1 and 2.9 kg more per decade than those averaging > 48 km x wk(-1). Age-related weight gain, and its attenuation by maintained exercise, were both greater in younger than in older men. Men's gains in waist circumference with age, and its attenuation by maintaining running, were the same in older and younger men. Regardless of age, women increased their body weight, waist circumference, and hip circumference over time, and these measurements were attenuated in proportion to their maintained running distance. In both sexes, running disproportionately prevented more extreme increases in weight.

CONCLUSION

As they aged, men and women gained less weight in proportion to their levels of sustained vigorous activity. This long-term beneficial effect is in addition to the acute weight loss that occurs with increased activity.

Physical activity and obesity prevention: a review of the current evidence

Ecological data on temporal trends suggest that the rising prevalence of obesity is, at least in part, attributable to declining population energy expenditure. However, population-level data on trends in physical activity are scarce. In longitudinal cohort studies individuals who report higher levels of leisure-time physical activity tend to be less likely to gain weight, but studies vary in their conclusions because of issues of confounding, reverse causality and measurement error. The majority of studies suggest that low levels of activity are only weakly associated with future weight gain. Questions about dose–response can only be properly addressed by studies including objective measures of activity with known measurement error. The observational studies leave uncertainties about the direction of causality, as individuals who are overweight are less likely to stay active. Adjustment for confounding can diminish the impact of known confounders, but only randomisation can deal with issues of unmeasured confounding. Although there are a large number of clinical trials on the treatment of individuals with obesity or the prevention of weight regain among weight losers, the updated review of trials to prevent weight gain de novo only reveals six trials published since 2000 in adults and eleven in children. Not only are these trials relatively few in number but, for various methodological reasons, they are uncertain in their conclusions about whether increasing activity will be effective in preventing obesity. Whilst efforts should continue to enhance the evidence base it is wise, in the meantime, to stick to the consensus public health advice of advocating 45–60 min moderate intensity activity daily to prevent obesity.

Determining lifestyle correlates of body mass index using multilevel analyses: the Tromsø Study, 1979-2001

Increases in overweight and obesity have been observed globally in both developed and developing countries. The authors assessed the relation between lifestyle factors and body mass index (BMI) (weight (kg)/height (m)2) in a population-based longitudinal study, using BMI and its subsequent change as responses in a multilevel model. The authors included 11,115 men and women aged 20-61 years at baseline who were living in the municipality of Tromsø, Norway, and who participated in three or four consecutive health surveys between 1979-1980 and 2001. Baseline age, physical activity at work, coffee consumption, and desired BMI (i.e., the BMI that the subjects reported they would like to have) were positively associated with baseline BMI, whereas height, alcohol consumption, leisure-time physical activity, and level of education were inversely associated. Most relations were found to be stronger in women than in men. Clinically relevant effect sizes were observed for most of the significant associations, especially in women. For instance, on an ordinal scale, a one-category increase in educational level would decrease the mean baseline BMI among women by 0.30 kg/m2. Significant associations between several lifestyle factors and subsequent BMI change revealed that observed baseline associations were strengthened over time, especially in women.

Resistance training increases total daily energy expenditure in disabled older women with coronary heart disease

Physical activity energy expenditure (PAEE) is a determinant of prognosis and fitness in older patients with coronary heart disease (CHD). PAEE and total energy expenditure (TEE) are closely related to fatness, physical function, and metabolic risk in older individuals. The goal of this study was to assess effects of resistance training on PAEE, TEE, and fitness in older women with chronic CHD and physical activity limitations ( N = 51, mean age: 72 + 5 yr). The study intervention consisted of a progressive, 6-mo program of resistance training vs. a control group condition of low-intensity yoga and deep breathing. The study interventions were completed by 42 of the 51 participants. The intervention group manifested a 177 ± 213 kcal/day (+9%) increase in TEE, pre- to posttraining, measured by the doubly labeled water technique during a nonexercise 10-day period ( P < 0.03 vs. controls). This was due to a 50 ± 74 kcal/day (4%) increase in resting metabolic rate measured by indirect calorimetry ( P < 0.01, P < 0.05 vs. controls) and a 123 ± 214 kcal/day (9%) increase in PAEE ( P < 0.03, P = 0.12 vs. controls). Resistance training was associated with significant increases in upper and lower body strength, but no change in fat-free mass, measured by dual X-ray absorptiometry, or left ventricular function, measured by echocardiography and Doppler. Women in the control group showed no alterations in TEE or its determinants. There were no changes between groups in body composition, aerobic capacity, or measures of mental depression. These results demonstrate that resistance training of 6-mo duration leads to an increase in TEE and PAEE in older women with chronic CHD.