Childhood obesity is increasing alarmingly, and a strong association with chronic diseases has been established. Specific adipokines are released from the adipose tissue and relate with chronic diseases even in the pediatric population. Adiponectin levels are lower in obesity and increase with decreasing body weight. A few pediatric studies examining a possible relationship between resistin and obesity do not provide a clear picture. Most studies agree that visfatin levels appear elevated in childhood obesity. Exercise seems to increase adiponectin levels whereas resistin levels are reduced. The lack of data on the effects of acute and chronic exercise on visfatin levels precludes us from making safe conclusions as to what the effects of exercise (acute or chronic) would be on visfatin levels in children. Clearly, exercise has an impact on the adipose tissue and the release of adiponectin, resistin, and visfatin. However, other factors affect the secretion rate of these adipokines from the adipose tissue; these factors should also be taken into consideration when examining the effects of exercise on adipokines. Gender, age, body composition, physical activity levels, mode and intensity of exercise are some of the factors that should be looked into in future studies.
Athanasios Z. Jamurtas, Antonios Stavropoulos-Kalinoglou, Stilianos Koutsias, Yiannis Koutedakis and Ioannis Fatouros
Clarice Martins, Ismael Freitas Jr., Andréia Pizarro, Luísa Aires, Gustavo Silva, Maria Paula Santos and Jorge Mota
Nonalcoholic fatty liver disease (NAFLD) is one of the most frequent complications associated with excess adiposity. Its pathogenesis is complex and there are multiple factors that may contribute to it. AIM: To analyze whether cardiorespiratory fitness (CRF), waist circumference (WC), and C-reactive protein (CRP) are associated with alanine aminotransferase (ALT) in children with obesity. METHODS: 79 overweight/obese children of both genders, 11–13 year-olds, with abnormal serum ALT from Porto public schools comprised the sample. Measurements included CRF (20-m Shuttle Run Test), WC (NHANES protocol), CRP and ALT (Cholestech LDX analyzer). Logistic regression adjusted for gender, maturation, and weight with ALT levels as dependent variable (risk vs. non risk), and WC (risk vs. non risk), CRP (risk vs. non risk), and CRF (fit vs. unfit) as independent variables. Level of significance was set at 95%. RESULTS: Logistic regression showed that obese fit children were less likely to have abnormal ALT values (OR=.031) CONCLUSION: In obese children, higher cardiovascular fitness appears to reduce the chance of decreased liver function.
Stephen P. Messier, Walter H. Ettinger Jr, Thomas E. Doyle, Timothy Morgan, Margaret K. James, Mary L. O'Toole and Robert Burns
The purpose of our study was to examine the association between obesity and gait mechanics in older adults with knee osteoarthritis (OA). Subjects were 101 older adults (25 males and 76 females) with knee OA. High-speed video analysis and a force platform were used to record sagittal view lower extremity kinematic data and ground reaction forces. Increased body mass index (BMI) was significantly related to both decreases in walking velocity and knee maximum extension. There were no significant relationships between BMI and any of the hip or ankle kinematic variables. BMI was directly related to vertical force minimum and maximum values, vertical impulse, and loading rate. Increases in braking and propulsive forces were significantly correlated with increased BMI. Maximum medially and laterally directed ground reaction forces were positively correlated with BMI. Our results suggests that, in subjects with knee OA, obesity is associated with an alteration in gait.
James J. Annesi
Although behavioral (nonsurgical/nonpharmacological) weight reduction interventions typically yield poor results beyond the short term, 1 – 3 exercise is viewed as the strongest predictor of long-term success with losing weight. 4 , 5 However, research on women with Class 3 (morbid) obesity
Jackie L. Puhl
The increasing prevalence of childhood obesity, persistence of obesity over time, and health risks associated with it place childhood obesity among the highest national health concerns. The extent to which excess caloric intake or insufficient energy expenditure contribute to childhood obesity has not yet been clearly delineated. This report examines the components of the energy alance equation, focusing on the major components of energy expenditure (rest, thermic effect of food, and physical activity) whereby differences may affect energy balance and promote or perpetuate obesity among children. Some implications of differences in energy expenditure to childhood obesity and areas of needed research are suggested.
James J. Annesi
mood improvement after initial gains were made? • Does change in PA-related self-efficacy mediate that (those) relationship(s)? Methods Participants Physically inactive women with a body mass index of 30 to 40 kg/m 2 (class 1–2 obesity) were originally recruited to contrast-related research 9 within
Roger L. Hammer, Daryl McCombs and A. Garth Fisher
It has been suggested that weight loss and regain, known as weight cycling, may result in greater body fatness and increased upper body fat distribution which may lead to adverse health consequences. These are concerns that may discourage some obese women from undergoing weight loss efforts. We retested 44 obese women, who took part in one of two weight control studies conducted in our laboratory, at either 6 or 12 months posttreatment. The followup study was performed to determine whether percent body fat and waist/hip ratio (WHR) had increased in those subjects who failed to maintain their weight loss. Subjects lost (mean + SD) 8.6 + 1.2 kg body weight, of which 7.0 + 1.0 kg was fat, and reduced their WHR by 0.03 + 0.006 (all p’s < .01) after either 12 or 16 weeks of treatment comprised of eating a low-fat diet, and in most cases performing endurance exercise training. At followup subjects were divided into groups based on the amount of weight regained. Those who regained (n=19) their lost weight were not fatter nor was their WHR higher than before the study began. These results do not support claims that weight cycling, in this case a single cycle, increases overall percentage of body fat or causes a redistribution of fat to the abdominal region of women.
Mollie G. DeLozier, Richard G. Israel, Kevin F. O’Brien, Robert A. Shaw and Walter J. Pories
This investigation quantified body composition and aerobic capacity and examined the interrelationships of these measures in 20 morbidly obese females (M age = 34.6 yrs) prior to gastric bypass surgery. Fifteen subjects were hydrostatically weighed at residual lung volume in order to determine body composition. Eighteen subjects performed a maximal modified progressive treadmill test to determine aerobic capacity. Results indicated that the 15 subjects who were weighed hydrostatically were heavier (M wt = 132.34 kg) and fatter (M % fat = 53.18) than any previously described individuals. Relative weight, which is used as a criterion to determine surgery eligibility, was not significantly (p > .05) correlated to percent body fat. Mean aerobic capacity (V̇O2 = 14.99 ml • kg-1 mir-1) was comparable to Class III cardiac patients and was limited by the individuals’ extreme body weight. Since relative weight was shown to be an insensitive measure of obesity, it is recommended that percent fat be measured and used as a means to determine eligibility for gastric bypass surgery. Further study of these individuals is warranted in order to determine what effects large weight loss following surgery will have on parameters of body composition and aerobic capacity. Understanding how large weight loss affects these parameters will aid in designing effective postsurgical exercise rehabilitative programs for future patients.
Meghan M. Senso, Stewart G. Trost, A. Lauren Crain, Elisabeth M. Seburg, Julie D. Anderson and Nancy E. Sherwood
Although the prevalence of obesity in young children highlights the importance of early interventions to promote physical activity (PA), there are limited data on activity patterns in this age group. The purpose of this study was to describe activity patterns in preschool-aged children and explore differences by weight status.
Analyses use baseline data from Healthy Homes/Healthy Kids–Preschool, a pilot obesity prevention trial of preschool-aged children who are overweight or at risk for being overweight. A modified parent-reported version of the previous-day PA recall was used to summarize types of activity. Accelerometry was used to summarize daily and hourly activity patterns.
“Playing with toys” accounted for the largest proportion of a child’s previous day, followed by “meals and snacks” and “chores.” Accelerometry-measured daily time spent in sedentary behavior, light PA, and moderate-to-vigorous PA (MVPA) was 412, 247, and 69 minutes, respectively. Percentage of hourly time spent in MVPA ranged from 3% to 13%, peaking in the late morning and evening hours. There were no statistically significant MVPA differences by weight status.
This study extends our understanding of activity types, amounts, and patterns in preschool-aged children and warrants further exploration of differences in PA patterns by weight status.
Holiday A. Durham, Miriam C. Morey, Cheryl A. Lovelady, Rebecca J. Namenek Brouwer, Katrina M. Krause and Truls Østbye
Low physical activity (PA) during the postpartum period is associated with weight retention. While patterns of PA have been examined in normal weight women during this period, little is known about PA among overweight and obese women. The aim of this cross-sectional study was to investigate PA and determine the proportion of women meeting recommendations for PA.
Women (n = 491), with a body mass index (BMI) ≥ 25 kg/m2 were enrolled in a behavioral intervention. PA was assessed at six weeks postpartum using the Seven-Day PA Recall.
Women averaged 923 ± 100 minutes/day of sedentary/ light and 33 ± 56 minutes/day of combined moderate, hard, and very hard daily activity. Women with a BMI ≥ 40 kg/m2 reported more time in sedentary/light activities and less hours of sleep than those with a lower BMI. Only 34% met national PA guidelines; this proportion was significantly lower among blacks (OR 0.5, CI 0.3−0.9).
These overweight and obese postpartum women reported a large percentage of time spent in sedentary/light activity, and a high proportion failed to meet minimal guidelines for PA. Promotion of PA in the postpartum period should focus on reducing sedentary behaviors and increasing moderate PA.