The effect of a four-month physical fitness program on a young and an old group matched for physical fitness.

A young (X = 36.8 years) and an old (X = 52.9 years) group (n = 12) matched for physical fitness performed a graded exercise test at the beginning and after a 4-month physical fitness program consisting of calisthenics, jogging, and recreational activities. The purpose of the study was to determine if there were any differences in response to physical training in the two age groups of similar fitness. Sixteen physiological and four biochemical variables were measured. There was no significant difference in VO2 max between the young and old groups. Also, there were no significant differences between groups for serum total lipids, cholesterol, triglycerides, or glucose levels. The effects of the training program were similar for both the young and old groups.     

Plyometric training effects on physical fitness and muscle damage in high school baseball players

[Purpose]The objective of this study was to investigate the effects of plyometric training on physical fitness and muscle damage in high school baseball players.[Methods]The participants in the study included 21 high school baseball players who are healthy and well-training. The participants were randomly allocated to the plyometric training (n=11) and control (n=10) groups. The plyometric training was applied 3 times a week for a total of 8 weeks and the control group took part in only regular baseball skills training without plyometric training. For physical fitness, measures included maximal strength (left and right hand-grip strength), muscle endurance (sit-up), agility (side-step), power (standing long jump), and balance (left and right Rhomberg test). For muscle damage, creatine kinase (CK) and lactate dehydrogenase (LDH) levels were measured.[Results]The results showed a significant interaction effect between time and groups in left hand-grip strength (P = 0.022), side-step (P = 0.004), and standing long jump (P < 0.001) after the 8-week plyometric training, with greater improvement in the plyometric training group than the control group. On the other hand, there was no significant interaction effect between time and groups in right hand-grip strength, situp, left and right Rhomberg test, CK level, and LDH level (P > 0.05).[Conclusion]In conclusion, 8-week plyometric training had a positive effect on improving physical fitness, such as maximal strength, agility, and power, in high school baseball players without causing additional muscle damage.     

Effect of Olympic and traditional resistance training on vertical jump improvement in high school boys

The purpose of this study was to compare the effects of a ballistic resistance training program of Olympic lifts with those of a traditional resistance training program of power lifts on vertical jump improvement in male high school athletes. Twenty-seven male student athletes were recruited from a high school football program at a small, rural school in the Southeast. The subjects were divided into an Olympic training group (OT, n = 11), a power training group (PT, n = 10), and a control group (n = 6). Analysis of variance was used to determine whether a significant mean difference existed among groups on vertical jump improvement after 8 weeks of group-specific training. Effect size of vertical jump improvement between groups, and correlations between strength and vertical jump performance, were also examined. There was no significant mean difference (p >or= 0.05) among OT, PT, and control groups, but large effect sizes between OT and control (d = 1.06) and PT and control (d = 0.94) demonstrate that both OT and PT are effective in improving vertical jump performance in male high school athletes. Moderate to high correlations were noted between squat score and vertical jump after adjusting for body weight (r = 0.42) and between power clean and vertical jump after adjusting for body weight (r = 0.75). Findings from the current study indicate that Olympic lifts as well as power lifts provide improvement in vertical jump performance and that Olympic lifts may provide a modest advantage over power lifts for vertical jump improvement in high school athletes.     

Parental misclassification of child overweight/obese status: The role of parental education and parental weight status

Childhood overweight and obesity is a major public health challenge for policymakers in many countries. As the most common supervisors of children’s activities, parents have a potentially important role to play in obesity prevention. However, a precondition for parents to improve their children’s diets, encourage them to be more physically active, or take them to see a doctor about their weight is for the parent to first recognize that their child is overweight or obese. This paper examines the extent of parental misclassification of child weight status, and its correlates, focusing on the role of parental education and the parent’s own obesity status. We find evidence that, among non-obese parents, those who are better-educated report their child’s weight status more accurately, but among obese parents, the better-educated are 45.18% more likely than parents with lower secondary education to give a false negative report of their child’s overweight/obesity; this may reflect social desirability bias.     

Effects of a short-term interval training program on physical fitness in prepubertal children

The aim of this study was to analyze the effects of a 7-week interval-training program on different aspects of physical fitness in children who were 8-11 years old. Forty-six boys and 54 girls (9.7 +/- 0.8 years) were divided into an experimental group and a control group. The 2 groups performed selected tests from the European physical fitness test battery before and after training. Training consisted of 2 specific 30-minute sessions per week of short high-intensity, intermittent-running aerobic exercises at velocities ranging from 100-130% of maximal aerobic speed. After training, the experimental group demonstrated a significant improvement in the standing broad jump (9.6%, p < 0.001, F = 12.9) and 20-meter shuttle run (5.4%, p < 0.001, F = 14.4), whereas for the control group, no significant changes were observed. It was concluded that a high-intensity, intermittent-running program improved children's aerobic performance and explosive strength.     

Evaluation of physical fitness from field tests at high altitude in circumpubertal boys: comparison with laboratory data

Field tests of running and laboratory tests were performed in La Paz [high altitude (HA), 3700 m] and in Clermont-Ferrand [low altitude (LA), 300 m] to investigate their validity at HA. Prepubertal boys of mean ages 10.6 years (HA1,n = 16; LA1,n = 28) and pubertal boys of 13.7 years (HA2,n = 12; LA2,n = 41) took part in the study. All the boys performed a 30-m sprint (v _30m), a 30-s shuttle run (v _3os) and a progressive shuttle run test until their maximal aerobic velocity (v _maxsRT). Maximal oxygen consumption was extrapolated from the last test. . In the laboratory, the boys performed a force-velocity test (P _max), a Wingate test (P _Wing) and a graded test to measure maximal oxygen consumption ; direct method) on a cycle ergometer. At similar ages, there was no significant difference between HA and LA boys forv _30m andP _max. Thev _30s of HA boys was 3%–4% lower than those of LA boys (P<0.05); there was no significant difference forP _Wing. Significant relationships were observed at both altitudes betweenP _max (watts per kilogram) andv _30m (HA:r=0.76; LA:r=0.84) and betweenP _Wing andv _30s (HA:r=0.67; LA:r = 0.77); the slopes and the origins were the same at HA and LA. The ,v _maxSRT and were lower by 9%, 12% and 20%, respectively, at HA than at LA (P<0.05). However, the relationships between and (litres per minute) at HA (r=0.88) and at LA (r=0.93) were identical. In conclusion, chronic hypoxia did not modify performance in very short dash exercises. The influence of HA appeared when the exercise duration increased and, during a maximal shuttle run test, performance was reduced by 10% at HA. Moreover, it was possible to assessP _max,P _Wing and at HA as well as at LA from field tests.     

Self-perceived body weight status and weight-control behaviors of high school students in a southern city of Turkey

Defining healthy weight is not easy and for an adolescent with all concerns about newly developing physiognomy it is even harder. The aim of this study was to find out the frequency of obesity and the association between the body mass index (BMI), weight-control behaviors and self-perceived body weight status in high school students of a southern city of Turkey. The students from 10 schools were randomly selected among 46,271 students of 72 high schools in Adana from 1999 to 2000. The response rate was 94.8% (2352/2480). The Turkish version of Youth Risk Behavior Survey Questionnaire (YRBSQ) was completed by the students. The students' weights and heights were measured. The mean age was 16.5 +/- 1.0 years of age (range = 14-21 years). The mean BMI was 21.0 +/- 3.1, 25.5% of students were underweight, 65.7% were normal, 6.4% were overweight and 2.3% were obese (p = 0.0001). Of all students, 24.3% defined themselves as thin, 45.3% as normal, 24.9% as overweight and 5.5% as obese (p = 0.0001). The percentage of girls defining their body weight as overweight and obese was significantly higher than the boys (p = 0.0001). Of all students, 35.5% wanted to lose weight, 22.3% wanted to gain weight, 27.8% wanted to keep their current weight. Intention (p = 0.0001) and interventions to lose weight such as going on a diet (p = 0.0001), provocative vomiting (p = 0.0001) and 24-hours starving (p = 0.0001) were significantly higher in girls than boys. Of students, 26.8% (n=620) were on a diet program either to lose or to keep their body weight. There was significant relationship between being on a diet program and intention to change body weight (p = 0.047). We concluded that adolescents living in Adana have relatively higher risk of being underweight than being obese and have unhealthy weight changing plans due to their misperception of their body images. Adolescents may be unconscious on plans and attempts to change their body weights and nutrition and we suggest that education on nutrition and health is required for adolescents.     

Active transportation to school over 2 years in relation to weight status and physical activity

Objective: To prospectively examine potential benefits of active commuting to school on measures of weight status and physical activity in a sample of youth. Research Methods and Procedures: A cohort of students from seven elementary schools was measured four times—in the fall and spring of fourth grade (N = 1083) and fifth grade (N = 924). Participants were classified as active (walking, biking, or skateboarding to school almost every day for baseline analyses or at least 2 d/wk for analyses of consistent active commuting) or non‐active commuters to school. Accelerometers were used to measure physical activity. Height, weight, and skinfolds were objectively assessed. Results: Boys who actively commuted to school had lower BMI (p < 0.01) and skinfolds (p < 0.05) than non‐active commuters to school in the fourth grade. Active commuting to school over 2 years was not associated with BMI change or overweight status. Discussion: Walking and cycling to school may contribute to preventing excessive weight gain, or leaner children may walk or cycle to school.     

Effects of 3 hours a week of physical activity on body fat and cardio-respiratory parameters in obese boys

The prevalence of overweight or fat children and adolescents has markedly increased in Hungary during the past three decades. Among the possible factors insufficient physical activity and a relative or absolute excess of calorie intake associated to it can be regarded as the most important ones. The aim of the study was to analyse the effects of a 20-week aerobic exercise on body composition and on the exercise tested cardio-respiratory functions in 10-year-old obese boys. Obesity was defined by a BMI greater than the cut-off value reported by Cole and co-workers (5) and a relative body fat content above 30% (13). Of the study group 21 volunteer children completed the program; the contrast group contained 28 obese boys. Mean calendar age was 10.03 +/- 0.26 in the study group (S) and 9.88 +/- 0.29 in the control group (C). The members of group S had two curricular physical education (PE) classes a week and three extracurricular aerobic physical activity sessions of 60 min net time in the afternoon, on Mondays (swimming and water games), Wednesdays (folk dance) and Fridays (soccer). Group C had only 2 PE classes a week. Anthropometric and spiroergometric data were collected in the middle of January and June of 2004. Relative body fat content and BMI did not increase during the observation period in contrast to the significant increase of both in the control group. Peak minute ventilation, aerobic power, oxygen pulse, and running distance (performed on a treadmill) increased in group S, and did not change in group C. The program was considered successful despite that the changes in the observed physiological and physical indicators appeared to be slight. However, the 5-month elevated level of physical activity brought about such development in the physical status of the obese subjects that might be an appropriate basis for regular training. Fortunately, the cardio-respiratory functions of the investigated boys were not affected yet by obesity, consequently the really dramatic change in their further lifestyle exclusively depends on their decision.     

Impact of a nutrition intervention program on the growth and nutritional status of Nicaraguan adolescent girls

This research examines the impact of a nutrition education intervention program on the nutritional status and knowledge of Nicaraguan adolescent girls. Anthropometric measurements, hemoglobin values, and data concerning nutritional knowledge were collected from adolescent girls living in Managua, Nicaragua. Using a pre-test/post-test design, data are compared prior to and after the nutrition intervention program. When using Mexican American reference data, statistically significant differences in height-for-age z-scores and weight-for-age z-scores were found when comparing the entire sample of baseline data with data collected after three years of the nutrition intervention program (p < 0.05). Significant improvement was also found concerning the indicators of nutritional knowledge (p < 0.05). However, hemoglobin data revealed a significant decrease which may be due to specific environmental factors and pubertal changes. This research has implications concerning the development of successful adolescent focused nutrition intervention programs in Nicaragua, and examines the possibility that catch-up growth occurs during adolescence.     

Trading nutrition for education: nutritional status and the sale of snack foods in an eastern Kentucky school

Overweight and poor nutrition of children in the United States are becoming issues of increasing concern for public health. Dietary patterns of U.S. children indicate they are consuming too few fruits and vegetables and too many foods high in fat and sugar. Contributing to this pattern of food consumption is snacking, which is reported to be on the increase among adults and children alike. One place where snacking is under increased scrutiny, and where it is being increasingly criticized, is in U.S. schools, where snack foods are often sold to supplement inadequate budgets. This article takes a biocultural approach to understanding the nutritional status of elementary school children in a rural community in eastern Kentucky. It pays particular attention to the ways in which the school's nutrition environment shapes overweight and nutritional status for many of the children, focusing on the sale of snack foods and the reasons behind the principal's decision to sell snack foods in the school.     

Hormonal and psychobehavioral predictors of weight loss in response to a short-term weight reduction program in obese women

Among the factors influencing weight loss and maintenance, psychobehavioral, nutritional, metabolic, hormonal and hereditary predictors play an important role. Psychobehavioral factors influence adherence to lifestyle changes and thus weight loss maintenance. The outcome of short-term weight reduction treatment is mainly affected by changes in energy and nutrient intake and physical activity and thus the impact of hormones can possibly be obscured. In order to reveal hormonal determinants of weight loss, a 4-week in-patient comprehensive weight reduction program was introduced in which food intake and physical activity were under the strict control. Women (n = 67, BMI: 32.4+/-4.4 kg; age: 48.7+/-12.2 years) who exhibited stable weight on a 7 MJ/day diet during the first week of weight management were given a hypocaloric diet yielding daily energy deficit 2.5 MJ over the subsequent 3-week period. This treatment resulted in a mean weight loss of 3.80+/-1.64 kg. Correlation analysis revealed that baseline concentrations of several hormones were significantly associated either with a higher (free triiodothyronine, C-peptide, growth hormone, pancreatic polypeptide) or with a lower (insulin-like growth factor-I, cortisol, adiponectin, neuropeptide Y) reduction of anthropometric parameters in response to weight management. In a backward stepwise regression model age, initial BMI together with baseline levels of growth hormone, peptide YY, neuropetide Y and C-reactive protein predicted 49.8 % of the variability in weight loss. Psychobehavioral factors (items of the Eating Inventory, Beck Depression score) did not contribute to weight change induced by a well-controlled short-term weight reduction program.     

Effect of a community-based weight management program on weight loss and cardiovascular disease risk factors

Objective: The purpose of our retrospective database analysis was to describe and evaluate the outcomes of a weight loss intervention in a community medical wellness center. Research Methods and Procedures: Four hundred eighteen overweight and obese adults entered the program between 2001 and 2004. Forty‐seven percent completed the 6‐month program designed using standards and recommendations established by the NIH, the American Dietetic Association, and the American Academy of Sports Medicine. Data analysis was limited to 198 participants (142 women, 56 men) completing the program. Results: Individuals completing the 6‐month program averaged a weight loss of 7.3% in men and 4.7% in women. Fasting lipids and blood glucose improved in both genders regardless of age. Outcomes including BMI and lipids improved in women regardless of menopausal status or hormone replacement therapy. There was a significant correlation between percentage weight loss and number of weekly counseling sessions attended and number of visits to the wellness center for exercise. Discussion: Participants who complete a structured community‐based weight management program can achieve significant weight loss and improvement in cardiovascular risk factors regardless of age, gender, or menopausal status. Our analysis suggests that national treatment guidelines/recommendations for weight management can be effectively implemented in a community medical wellness center. The relatively high drop‐out rate associated with this program suggests the need to identify strategies and techniques to enhance adherence and completion of programs.