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Despite interventions designed to change behavior, many adolescents continue to consume unhealthy foods. Dietary patterns are important for disease prevention, making it necessary to understand the reasons for these poor choices. ...
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Despite interventions designed to change behavior, many adolescents continue to consume unhealthy foods. Dietary patterns are important for disease prevention, making it necessary to understand the reasons for these poor choices. This cross-sectional study explored the relationship between perception of dietary practices and dietary behaviors among adolescents. Participants (n=15,283; mean age=15 years; 50.7% female) completed the 2004-2005 Texas School Physical Activity and Nutrition survey. Perception of dietary practices included fat content of foods usually eaten and healthiness of usual eating habits. Dietary behavior was measured by self-report of foods eaten the day before survey administration. Composite scores of unhealthy and healthy eating were created. Regression analyses examined whether perception of dietary practices was consistent with actual dietary behavior, controlling for sex, grade, and race/ethnicity, and accounting for the complex sampling design. Higher perceived fat content was associated with increased consumption of unhealthy foods, while higher perceived healthiness of eating was associated with increased consumption of healthy foods. For perceived fat content, the difference in the Healthy Eating Index between extreme categories was 26% (P<0.001), while the difference in the Unhealthy Eating Index between extreme categories was 81% (P<0.001). For perceived healthiness, the difference in the Healthy Eating Index between extreme categories was 23% (P<0.001), while the difference for the Unhealthy Eating Index was 44% (P<0.001). Self-perceptions of dietary practices were significantly associated with dietary behaviors, indicating awareness about the relative nutrient content of foods consumed. Interventions that move beyond dietary knowledge and create changes in the social and physical environment are needed.Digital Object Identifier http://dx.doi.org/10.1016/j.jada.2011.08.003
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Although research indicates that empathy inhibits youth aggression, little is known about the prospective associations between different components of empathy and aggression, as well as whether family and school factors moderate t...
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Although research indicates that empathy inhibits youth aggression, little is known about the prospective associations between different components of empathy and aggression, as well as whether family and school factors moderate the aforementioned associations in early adolescents. Based on prior research, the current study examined whether empathic concern and perspective taking would contribute to subsequent overt and relational aggression over a 1-year period in middle school. Guided by the social development model, we also examined if positive family relations and school connectedness would differentially moderate the associations between both components of empathy and aggression. Participants were 481 10- to 14-year old students (54 % female; 78 % European American) who completed the first wave of a survey in 6th and 7th grades. Hierarchical regression analyses indicated that only for girls did lower levels of empathic concern, not perspective taking, contribute to increases in subsequent overt, not relational, aggression. Although neither positive family relations nor school connectedness played protective roles for girls, results indicated that boys' reports of positive family relations buffered the negative impact of low empathic concern on both forms of aggression 1 year later. Over and above the two components of empathy, school connectedness also contributed to a decline in boys' subsequent overt aggression. Recommendations are made to foster family and school relationships among boys, as well as to more heavily consider the role of emotion processes in the study and prevention of early adolescents' aggression.
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Muscle force potentiation affects force output during electrical stimulation. Few studies have examined stimulation train parameters that influence potentiation such as pulse number, stimulation frequency, train duration, and forc...
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Muscle force potentiation affects force output during electrical stimulation. Few studies have examined stimulation train parameters that influence potentiation such as pulse number, stimulation frequency, train duration, and force–time integral and peak force produced during the train. Pulse-matched trains (100 pulses) at 7.5, 15, 25, 30, 50, and 100 Hz, and trains of varying pulse number (50, 100, and 200 pulses) at 30 and 50 Hz were delivered to the ulnar nerve of 10 (5 male, 5 female; 23.4 ± 0.9 years), healthy individuals in random order. Single twitches of the adductor pollicis muscle were elicited before and after each train with a rest interval of at least 5 min between each train. No differences in potentiation occurred across the pulse-matched trains at frequencies of 15–50 Hz (38.9 ± 5.4–44.6 ± 5.5%). Twitch force potentiation following the highest (100 Hz) and lowest (7.5 Hz) frequency trains were not significantly different and were lower than the other 100 pulse-matched trains. As pulse number increased, potentiation increased for both the 30 and 50-Hz trains. There was a significant positive correlation between force potentiation and force–time integral produced by the stimulation train, r = 0.70. The results indicate that potentiation magnitude is dependent on the force–time integral produced during the test train and the number of pulses delivered, independent of stimulation frequency.
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This study examined adaptation to work stress among public school teachers (n = 267). Regression analyses tested whether positive affect predicted successful and unsuccessful adaptation to stress (viz., resilience and burnout, res...
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This study examined adaptation to work stress among public school teachers (n = 267). Regression analyses tested whether positive affect predicted successful and unsuccessful adaptation to stress (viz., resilience and burnout, respectively) after controlling for demographic characteristics and work stress. Positive affect was largely correlated with resilience (r =.65, p &.001) and burnout (r = -.57, p &.001). The regression of resilience showed that positive affect had a direct effect (β =.66, p &.001) and the total model explained 44 % of the variance (R~2Change = 37 %). In the regression of burnout, positive affect also had a direct effect (β = -.41, p &.001) and the total model explained 52 % of the variance (R~2Change = 14 %). Further analyses found no significant interaction between work stress and positive affect, but revealed that positive affect completely mediated the effect of work stress on resilience. Results provide support for the broaden-and-build theory of positive emotions, particularly the theory's building and undoing effects.
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To replicate previous research that concluded exercise affects health via a placebo effect: simply telling workers with physically active jobs that their "work is exercise" improves health. Method: A convenience sample of universi...
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To replicate previous research that concluded exercise affects health via a placebo effect: simply telling workers with physically active jobs that their "work is exercise" improves health. Method: A convenience sample of university building service workers (n=53) learned "their work is exercise" or about job safety. Results: Groups demonstrated similar outcomes at 4 and 8 weeks for weight, percent fat, waist circumference, and behavioral measures. Both groups increased self-perception as "regular exercisers"; blood pressure was reduced only in the intervention group. Conclusion: This research did not support the placebo effect. Although enticing, simply changing mind-set does not alter the relationship between exercise and health.
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Objective: Current nutrition environment instruments are typically designed to measure a small number of healthy foods based on national trends. They lack the depth to accurately measure the unique dietary choices of subpopulation...
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Objective: Current nutrition environment instruments are typically designed to measure a small number of healthy foods based on national trends. They lack the depth to accurately measure the unique dietary choices of subpopulations, such as Texas consumers whose food preferences are influenced by Hispanic/Latino culture. Thus the purposes of the present study were to: (i) develop a comprehensive observational tool to measure the availability of healthy foods from retail stores in Texas; and (ii) conduct a pilot test to examine the tool's reliability, as well as differences in the availability of healthy foods in stores between high- and low-income neighbourhoods. Design: Grocery and convenience stores were assessed for availability of healthy foods. Reliability was calculated using percentage agreement, and differences in availability were examined using 2 (store type) x 2 (neighbourhood income) ANOVA. Setting: One high-income and one low-income neighbourhood in Austin, Texas. Subjects: A sample of thirty-eight stores comprising twenty-five convenience stores and thirteen grocery stores. Results: The low-income neighbourhood had 324% more convenience stores and 56% fewer grocery stores than the high-income neighbourhood. High inter-rater (mean=0.95) and test-retest reliability (mean=0.92) and a significant interaction (P=0.028) between store type and neighbourhood income were found. Conclusions: The TxNEA-S tool includes 106 healthy food items, such as fruits, vegetables, dairy, proteins and grains. The tool is reliable and face validity is affirmed by the Texas Department of Health. Grocery stores have more healthy foods than convenience stores, and high-income grocery stores offer more healthy foods than low-income grocery stores.Digital Object Identifier http://dx.doi.org/10.1017/S1368980010001588
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An innovative exercise machine, which mimics the movement of horseback riding, has been made available in the market. As an initial step in characterizing this device, we determined the cardiovascular and metabolic responses to ex...
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An innovative exercise machine, which mimics the movement of horseback riding, has been made available in the market. As an initial step in characterizing this device, we determined the cardiovascular and metabolic responses to exercise. Twenty apparently healthy subjects rode the device (Equus) on day 1. The upper body exercises were added on day 2, to see whether cardiac and metabolic demands were further elevated (Equus+aerobics). After 10 min of continuous exercise, oxygen consumption increased significantly. In the Equus+aerobics condition, increase in oxygen consumption was significant as early as 4 min into the graded exercise test. Overall oxygen consumption was greater in the Equus+aerobics condition than in the Equus condition (P<0.05). Oxygen consumption returned to baseline levels within 1 h after the Equus (190+or-58-188+or-50 ml min-1) and Equus+aerobics (198+or-54-194+or-43 ml min-1) conditions. Heart rates increased gradually during the graded exercise tests in both conditions (64+or-11-78+or-15 and 65+or-11-83+or-12 bpm in the Equus and Equus+aerobics conditions, respectively). Both systolic and diastolic blood pressure (BP) increased significantly 6 min into the graded exercise tests and remained elevated throughout exercise in both the conditions. There were no significant differences in BP responses between the two conditions. These results indicate that the cardiac and metabolic stresses achieved with this exercise device are small.
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Although students enrolled in trade or technical colleges are at an elevated risk for tobacco use, virtually no information exists regarding their smoking behaviors. OBJECTIVE AND PARTICIPANTS: In the present study, the authors ex...
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Although students enrolled in trade or technical colleges are at an elevated risk for tobacco use, virtually no information exists regarding their smoking behaviors. OBJECTIVE AND PARTICIPANTS: In the present study, the authors examined (1) the prevalence of smoking and quitting among 617 students in 2 trade or technical colleges in East Texas and (2) on-campus media exposure to antitobacco messages. METHODS: Students voluntary completed the 42-item Texas Trade and Technical School Tobacco Survey during a required introductory-level class. RESULTS: Of the participating students, 34% reported past-30-day smoking (current smoking). Of current smokers, 74% reported a previous quit attempt and 64% wanted to quit before graduation. Although most current smokers expressed a desire to quit smoking, the antitobacco message they were least likely to see on campus was that regarding how to quit. Current smokers cited their own health as the most likely reason to quit smoking, and most reported wanting to quit on their own, without the use of resources. However, of the 9 listed resources, students were most likely to report the possible use of medication. CONCLUSIONS: Given that most smoking students desire to quit smoking--and that they are enrolled in trade or technical schools for an extended period of time--additional research should examine how successful interventions can be delivered at the trade or technical school itself.
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Although students enrolled in trade or technical colleges are at an elevated risk for tobacco use, virtually no information exists regarding their smoking behaviors. OBJECTIVE AND PARTICIPANTS: In the present study, the authors ex...
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Although students enrolled in trade or technical colleges are at an elevated risk for tobacco use, virtually no information exists regarding their smoking behaviors. OBJECTIVE AND PARTICIPANTS: In the present study, the authors examined (1) the prevalence of smoking and quitting among 617 students in 2 trade or technical colleges in East Texas and (2) on-campus media exposure to antitobacco messages. METHODS: Students voluntary completed the 42-item Texas Trade and Technical School Tobacco Survey during a required introductory-level class. RESULTS: Of the participating students, 34% reported past-30-day smoking (current smoking). Of current smokers, 74% reported a previous quit attempt and 64% wanted to quit before graduation. Although most current smokers expressed a desire to quit smoking, the antitobacco message they were least likely to see on campus was that regarding how to quit. Current smokers cited their own health as the most likely reason to quit smoking, and most reported wanting to quit on their own, without the use of resources. However, of the 9 listed resources, students were most likely to report the possible use of medication. CONCLUSIONS: Given that most smoking students desire to quit smoking--and that they are enrolled in trade or technical schools for an extended period of time--additional research should examine how successful interventions can be delivered at the trade or technical school itself.
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Engagement in regular aerobic exercise is associated with cognitive benefits, but information on the mechanisms governing these changes in humans is limited. The goal of the current study was to compare neurometabolite concentrati...
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Engagement in regular aerobic exercise is associated with cognitive benefits, but information on the mechanisms governing these changes in humans is limited. The goal of the current study was to compare neurometabolite concentrations relating to cellular metabolism, structure, and viability in endurance-trained and sedentary middle-aged adults. Twenty-eight endurance-trained and 27 sedentary adults, aged 40-65 years, underwent general health assessment, cardiorespiratory fitness measurement, neuropsychological testing, and proton magnetic resonance spectroscopy (1H MRS). 1H MRS was used to examine N-acetyl-aspartate (NAA), creatine (Cr), myo-inositol (mI), choline (Cho), and glutamate (Glu) concentrations in frontal and occipitoparietal grey matter. Group differences in concentrations of NAA, Cho, mI, and Glu, calculated as ratios over Cr, were explored using ANOVA. There were no significant differences in global cognitive function, memory, and executive function performance between the groups. In comparison to sedentary adults, the endurance-trained group displayed significantly higher NAA/Cr in the frontal grey matter (F(1, 53) = 5.367, p = 0.024) and higher Cho/Cr in the occipitoparietal grey matter (F(1, 53) = 5.138, p = 0.028). Within our middle-aged sample, endurance-trained adults demonstrated higher levels of NAA/Cr in the frontal grey matter and higher Cho/Cr in the occipitoparietal grey matter. Higher levels of NAA may indicate greater neuronal integrity and higher cerebral metabolic efficiency in association with cardiorespiratory fitness, whereas increased Cho may represent increased phospholipid levels secondary to neural plasticity.
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