Implications of the traditional and the new ACSM physical activity recommendations on weight reduction in dietary treated obese subjects

You Are What You Tweet: Connecting the Geographic Variation in America's Obesity Rate to Twitter Content

We conduct a detailed investigation of the relationship among the obesity rate of urban areas and expressions of happiness, diet and physical activity on social media. We do so by analyzing a massive, geo-tagged data set comprising over 200 million words generated over the course of 2012 and 2013 on the social network service Twitter. Among many results, we show that areas with lower obesity rates: (1) have happier tweets and frequently discuss (2) food, particularly fruits and vegetables, and (3) physical activities of any intensity. Additionally, we provide evidence that each of these results offer different and unique insight into the variation of the obesity rate in urban areas within the United States. Our work shows how the contents of social media may potentially be used to estimate real-time, population-scale measures of factors related to obesity.

Volume and intensity of physical activity in a large population-based cohort of middle-aged and older Australians: prospective relationships with weight gain, and physical function

OBJECTIVES

To examine prospectively whether higher proportions of vigorous physical activity (VPA), independent of total activity volume, are associated with better outcomes in weight maintenance and physical function.

METHODS

We used three-year longitudinal data (2006/07-2009/10) of adults 45 and older (n=32,087; 59.5±9.3years) from New South Wales, Australia. Logistic regression models examined odds of weight gain and functional decline by volume and intensity of physical activity.

RESULTS

On average, body weight increased by 0.66kg (SD=5.83, p<0.001); a validated physical function score (MOS-PF) decreased by 4.79 (SD=12.56, p<0.001). There was a 10% reduction in the odds of weight gain for participants who reported 300min/week or more of moderate to vigorous physical activity (MVPA) compared to less than 150min of MVPA. The proportion of MVPA that was vigorous was not associated with weight change. With the physical functioning outcome, there were independent protective effects from volume and intensity of physical activity. Independent of total MVPA, each 1% increase in the proportion of total activity that was vigorous was associated with a 0.3% decrease in the odds of decline in physical function.

CONCLUSION

These prospective findings indicate that VPA per se plays an important role in the prevention of functional decline.

Yoga training improves metabolic parameters in obese boys

Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.

Relationship between the metabolic syndrome and physical activity energy expenditure: a MONET study

The purpose of this cross-sectional study was to examine the association between the metabolic syndrome (MetS) and physical activity energy expenditure (PAEE) in overweight and obese sedentary postmenopausal women. The study population consisted of 137 overweight and obese sedentary postmenopausal women (age, 57.7 ± 4.8 years; BMI, 32.4 ± 4.6 kg·m–2). Subjects had the MetS if 3 out of the following 5 criteria were met: visceral fat > 130 cm2, high-density lipoprotein (HDL) cholesterol < 1.29 mmol·L–1, fasting triglycerides ≥ 1.7 mmol·L–1, blood pressure ≥ 130/85 mmHg, and fasting glucose ≥5.6 mmol·L–1. We measured (i) body composition (by dual-energy X-ray absorptiometry); (ii) visceral fat (by computed tomography); (iii) insulin sensitivity (using the hyperinsulinemic-euglycemic clamp); (iv) plasma lipids, fasting glucose, and insulin, as well as 2 h glucose during an oral glucose tolerance test; (v) resting blood pressure; (vi) peak oxygen consumption (VO2 peak); (vii) PAEE (using doubly labeled water); and (viii) lower-body muscle strength (using weight-training equipment). Forty-two women (30.7%) had the MetS in our cohort. Individuals without the MetS had significantly higher levels of PAEE (962 ± 296 vs. 837 ± 271 kcal·d–1; p < 0.05), VO2 peak (18.2 ± 3.0 vs. 16.7 ± 3.2 mL·min–1·kg–1; p < 0.05), and insulin sensitivity, as well as significantly lower levels of 2 h glucose and central lean body mass. No differences in total energy expenditure, resting metabolic rate, and muscle strength between groups were observed. Logistic regression analysis showed that 2 h glucose (odds ratio (OR): 1.50 (95% CI 1.17–1.92)), central lean body mass (OR: 1.17 (95% CI 1.05–1.31)), and PAEE (OR: 0.998 (95% CI 0.997–1.000)), but not VO2 peak and (or) muscle strength, were independent predictors of the MetS. Lower levels of PAEE and higher levels of 2 h glucose, as well as central lean body mass, are independent determinants of the MetS in our cohort of overweight and obese postmenopausal women.

Comparison of two physical activity questionnaires in obese subjects: the NUGENOB study

PURPOSE

Simple instruments are needed to assess habitual physical activity (PA) in obese subjects. In a multicenter European obesity project, we tested whether PA assessments by two questionnaires were correlated and similarly associated to selected obesity-related variables.

METHODS

A total of 757 obese subjects (75% female; age 37.1 [7.9] yr, BMI 35.5 [4.9] kg.m(-2), mean [SD]) completed the Baecke questionnaire (assessing work, sport, and nonsport leisure activity) and the short last 7-d version of the International Physical Activity Questionnaire (IPAQ; assessing vigorous, moderate-intensity, walking activity, and sitting). We assessed percent body fat (bioimpedance), waist circumference, and fasting plasma concentrations of glucose, insulin, leptin, and FFA. Insulin sensitivity was assessed by the HOMA index for insulin resistance (HOMAIR).

RESULTS

Using the IPAQ, only about one third of men and women were classified as insufficiently active. Total habitual PA assessments by the Baecke and IPAQ were significantly related (Spearman rho = 0.51 in total sample, P < or = 0.0001, with adjustment for age, gender, and center). Using principal component analysis, we built two uncorrelated indices corresponding to general obesity (determined by high body fat and leptin) and abdominal obesity (determined by high waist circumference and HOMAIR). PA scores from both questionnaires were negatively related to general and abdominal obesity indices, except for abdominal obesity with the IPAQ in men.

CONCLUSIONS

Total PA assessments by the two questionnaires were found to correlate significantly, and the general pattern of associations of PA with general obesity was similar for the two questionnaires. However, the IPAQ may capture less of the relationships between PA and abdominal obesity than the Baecke, especially in men. Reporting of habitual PA in obese subjects with the IPAQ warrants further evaluation against objective assessment methods.

Exercise does not feel the same when you are overweight: the impact of self-selected and imposed intensity on affect and exertion

OBJECTIVE

The lower rates of adherence to physical activity commonly found among overweight adults compared to their normal-weight counterparts might be due to the activity being experienced as more laborious and less pleasant, particularly when its intensity is prescribed (or imposed) rather than self-selected.

DESIGN

Within-subject design, with two 20-min sessions of treadmill exercise, one at self-selected speed and one at imposed speed, 10% higher than the self-selected.

SUBJECTS

A total of 16 overweight (BMI: 31 kg/m2) and 9 normal-weight (BMI: 22 kg/m2) previously sedentary but healthy women (age: 43 years).

MEASUREMENTS

Heart rate, oxygen uptake relative to body weight, and ratings of perceived exertion and pleasure-displeasure were assessed every 5 min.

RESULTS

The overweight women showed higher oxygen uptake and perceived exertion than the normal-weight women during both sessions. Although the two groups did not differ in ratings of pleasure-displeasure during the session at self-selected speed, only the overweight women showed a significant decline when the speed was imposed.

CONCLUSIONS

Imposing a speed that is just 10% higher than what overweight women would have self-selected led to a significant decline in reported pleasure. Over time, this could diminish the enjoyment of and intrinsic motivation for physical activity, reducing adherence.

Estimated physical activity in Bavaria, Germany, and its implications for obesity risk: results from the BVS-II Study

Background

Adequate physical activity (PA) is considered as a key factor in the fight against the obesity epidemic. Therefore, detailed description of the actual PA and its components in the population is necessary. Additionally, this study aims to investigate the association between PA and obesity risk in a representative population sample in Bavaria, Germany.

Methods

Data from 893 participants (age 13–80 years) of the Bavarian Food Consumption Survey II (BVS II) were used. In each participant, three computer-based 24-hour recalls were conducted by telephone assessing type and duration of PA in the domains occupation, sports, other strenuous leisure time activities (of mostly moderate intensity) as well as TV/PC use in leisure time and duration of sleeping. After assigning metabolic equivalents (METs) to each activity, estimates of energy expenditure (MET*h) and total daily PA level (PAL_est.) were calculated. In a subgroup of adults (n = 568) with anthropometric measurements logistic regression models were used to quantify the impact of PA on obesity risk.

Results

Estimated average PA in women and men was 38.5 ± 5.0 and 40.6 ± 9.3 MET*h/d, respectively, corresponding to PAL_est. values of 1.66 ± 0.22 and 1.75 ± 0.40. Obese subjects showed lower energy expenditure in the categories sports, occupation, and sleeping, while the time spent with TV/PC during leisure time was highest. This is confirmed in logistic regression analyses revealing a statistically significant association between obesity and TV/PC use during leisure time, while sports activity was inversely related to obesity risk. Overall, less than 1/3 of the study participants reached the recommended PAL of ≥ 1.75. Subjects within the recommended range of PA had an about 60 % (odds ratio = 0.43; 95% CI: 0.21–0.85) reduced risk of obesity as compared to inactive subjects with a PAL_est. <1.5.

Conclusion

Based on the results of short-term PA patterns, a major part of the Bavarian adult population does not reach the recommendations (PAL>1.75; moderate PA of > 30 min/d). Despite the limitations of the study design, the existing associations between sports activity, TV/PC use and obesity risk in this population give further support to the recommendation of increasing sports activity and reducing sedentary behaviour in order to prevent rising rates of obesity.

Barriers to physical activity in patients with diabetes

PURPOSE

Two questions were addressed: (1) How much physical activity do patients with diabetes perform? (2) What are the perceived factors that prevent patients from doing more physical activity?

RESEARCH DESIGN AND METHODS

Interview based questionnaires were distributed to consecutive patients attending the Diabetes Clinic, Ninewells Hospital, Dundee over a period of five months. Exclusion criteria were age below 20 years and inadequate understanding of English; 428 questionnaires were given out with 406 completed.

RESULTS

Physical activity was undertaken by 34% of patients with diabetes and only 9% of these patients exercised sufficiently to achieve a large change in heart rate or breathing. The main reasons for inactivity included perceived difficulty taking part in exercise, feelings of tiredness, and being distracted by something good on television. Lack of time and lack of local facilities also contributed.

CONCLUSIONS

Few patients with diabetes participate in physical activity, and in those who do the level of intensity is low. There are many modifiable factors distracting patients from exercise.

Physical activity in the management of obesity

Physical activity is any movement of skeletal muscles that results in energy expenditure. Long-term success in weight management depends on both physical activity and dietary modification. Exercise has a pivotal role in weight management, optimising body composition by minimising fat-free mass losses and maximising fat mass loss; and, enhancing metabolic fitness. The amount and type of exercise needed to obtain health-related benefits may differ from that recommended for fitness benefits. Public health messages about exercise have focused on improvements in general health and fitness rather than on weight loss, prevention of weight gain or weight regain. About 2.5 times more exercise than the US Surgeon General's recommendation is needed to maintain energy balance and thus maintain a certain weight. The challenge is to get the exercise prescription right at an individual level.

How much activity do youth get? A quantitative review of heart-rate measured activity

OBJECTIVE

Recommendations for adult physical activity have shifted from 20 to 60 minutes of continuous vigorous activity 3 to 5 times a week to accumulation of 30 minutes of moderate to vigorous physical activity most days of the week. Variations of these guidelines also have been suggested for children, based on the idea of accumulating moderate to vigorous physical activity throughout the day, rather than attaining vigorous physical activity in continuous blocks. The goal of this study was to assess accumulated amounts of physical activity at different intensities in children.

METHODS

We reviewed 26 studies (n = 1883) in youth aged 3 to 17 years that used heart-rate recording to measure physical activity in children to determine accumulated daily activity. Included were studies that provided time being active for at least 2 heart rate intensities at or above 120 beats/minute. Descriptive characteristics of the study groups were determined, and the influence of age, gender, and hours and days of observation on the slope of activity time as a function of percentage of heart rate reserve (HRR) was determined using hierarchical linear regression.

RESULTS

Youth attained 128.0 +/- 45.6, 47.1 +/- 14.9, 29.3 +/- 13.7, and 14.7 +/- 6.0 minutes/day between 20% to 40%, 40% to 50%, 50% to 60%, and greater than 60% HRR, respectively. Age was a significant predictor of the intercept and slope of the physical activity and %HRR relationship.

CONCLUSION

Youth of all ages attain >60 minutes/day of low-intensity physical activity and approximately 30 minutes/day of activity at traditional cardiovascular fitness training levels of 50% or more of HRR. Recommendations for youth activity are discussed.

Health benefits of physical activity with special reference to interaction with diet

Regular physical activity causes numerous and substantial performance-improving and health-enhancing effects. Most of them are highly predictable, dose-dependent and generalizable to a wide range of population groups. Many of the biological effects of regular, moderate physical activity translate into substantially reduced risk of coronary heart disease, cerebrovascular disease, hypertension, maturity onset diabetes, overweight and obesity, and osteoporosis. These effects also substantially reduce the risk of deterioration of functional capacity. In the genesis of these conditions, a lack of physical activity and inadequate nutrition act synergistically and in part additively, and they operate largely through the same pathways. It is conceivable to suggest that the prevalence of, e.g, the above mentioned metabolic diseases is so high in Europe largely because of the high prevalence of sedentariness and inadequate nutrition. Thus, both physical activity and nutrition have to be given strong emphasis in policies, strategies and programmes that will be developed and implemented for improving the health of Europeans.

Challenges and opportunities for measuring physical activity in sedentary adults

Increasing the physical activity of typically sedentary adult populations is at the forefront of the public health agenda. This review addresses the challenges in defining and measuring physical activity in this target group, for a number of purposes, namely, scientific or academic inquiry, surveillance, clinical application and programme evaluation. First, we clarify the conceptual distinctions between the terms sedentarism, physical inactivity, physical activity and energy expenditure. Next, we review and compare the utility of different approaches for quantifying and expressing physical activity in these populations. Physical activity in typically sedentary populations is most likely a simple pattern of behaviour that has been largely obscured by existing measures and its expression as energy expenditure. Existing self-report methods are practical, but suffer from floor effects and recall bias. Walking, the most important activity to assess in this target group, is very difficult to measure through self-report methods. Motion sensors are more appropriate for quantifying physical activity behaviours in typically sedentary populations. Of the 2 types of motion sensors - the accelerometer and the pedometers--the latter is more appealing because it is both an affordable and a 'good enough' measure of physical activity, specifically ambulatory activity. Although a common measurement approach would greatly facilitate our understanding of physical activity behaviour patterns, the selection of an approach ultimately depends on the purpose of the study and to a great extent, its budget. Researchers, clinicians and practitioners interested in accurately capturing the lower end of the continuum of physical activity (that is characteristic of sedentary populations) must thoughtfully consider the relative advantages and disadvantages of the available approaches.

Quality and correlates of physical activity counseling by health care providers in Israel

BACKGROUND

The quantity and quality of physical activity counseling by the health care provider can have a profound impact on improving the physical activity of the older population. This study presents an estimate of the quality and quantity of physical activity counseling and tests the associations of different variables with physical activity.

METHODS

A random telephone survey of 793 Israeli residents between the ages of 45 and 75 was conducted. Counseling by a health care provider was evaluated using a three-stage approach--assess, advise, and assist.

RESULTS

Of those visiting a doctor in the last 3 months 22, 16, and 7% were assessed, advised, and assisted, respectively, regarding physical activity by a health care provider. At all three stages, receiving weight reduction counseling was a main variable correlated with receiving physical activity counseling (OR 3.38-2.43). Having a chronic disease was associated with being assessed; smoking and being a recent immigrant were associated with getting assistance on physical activity. Visiting a health care provider in the last 3 months, and being physically active were also associated with counseling. The dietitians and the physicians had the highest quality and rates of counseling in all three stages.

CONCLUSION

It seems that a sedentary lifestyle is not regarded as an independent risk factor during counseling, but more as an important part of weight reduction. An evaluation of physical activity counseling by the three stages can be used to assess the quality of the counseling.

Diabetes and exercise

Exercise is frequently recommended in the management of type 1 and 2 diabetes mellitus and can improve glucose uptake by increasing insulin sensitivity and lowering body adiposity. Both alone and when combined with diet and drug therapy, physical activity can result in improvements in glycaemic control in type 2 diabetes. In addition, exercise can also help to prevent the onset of type 2 diabetes, in particular in those at higher risk, and has an important role in reducing the significant worldwide burden of this type of diabetes. Recent studies have improved our understanding of the acute and long term physiological benefits of physical activity, although the precise duration, intensity, and type of exercise have yet to be fully elucidated. However, in type 1 diabetes, the expected improvements in glycaemic control with exercise have not been clearly established. Instead significant physical and psychological benefits of exercise can be achieved while careful education, screening, and planning allow the metabolic, microvascular, and macrovascular risks to be predicted and diminished.