Purpose. The aim of this study was to analyze the interrelationships among motor coordination, body fat percentage, and physical activity levels in adolescent girls. Methods. Sixty-eight girls aged 12–14 years participated in the study. Skinfold thickness was measured and the Körperkoordinationstest für Kinder test was administered. Participants completed a self-reporting questionnaire on physical activity. Bivariate and partial correlations were used to analyze the interrelationships among the selected variables. Results. There were no significant (p > 0.05) correlations between any motor coordination scores and physical activity levels with and without controlling for body fat percentage. All motor coordination scores were significantly (p < 0.05) associated with body fat with and without controlling for physical activity levels. Conclusions. The relationships between motor coordination scores and physical activity levels, as well as between motor coordination scores and body fat percentage, were not influenced by body fat and physical activity levels, respectively. However, the overall low physical activity level in this sample may have biased these results. Additional research involving girls with higher physical activity levels should be pursued.
Key words: motor skills, physical activity, adiposity, children, adolescence, health
Purpose. The aim of the present investigations was to determine the effects of aqua aerobics on body weight and composition, lipid profile, and selected blood count parameters in middle-aged sedentary females. Methods. Twenty-one women were randomly assigned to an experimental group (age 56.20 ± 2.57 years, height 162.80 ± 4.76 cm, weight 74.03 ± 3.84 kg) that participated in aqua aerobics classes three times a week for three months and a control group (mean age 56.44 ± 3.28 years, height 165.00 ± 3.91 cm, weight 70.01 ± 11.36 kg) not involved in any kind of targeted exercise. The aqua aerobics classes were tailored to suit the age and abilities of the participants, with workout intensity controlled and maintained at approximately 128–137 bpm. Results. Significant differences between the experimental and control groups were found for body weight, total body water, fat-free mass, and skeletal muscle mass. A significant increase in post-intervention hemoglobin and erythrocyte counts was observed in theexperimental group. Conclusions. Future studies should determine the intensity of physical activity with the most beneficial effect on blood variables in middle-aged and older individuals.
Key words: body composition, lipid profile, blood count parameters, aqua aerobics, middle-aged female
Purpose. The aim of the study was to evaluate and compare the physical activity patterns of preschoolers aged 6–7 years. Methods. A sample of 221 preschool children (116 boys and 105 girls) aged 6 (5.92 ± 0.30) and 7 (6.91 ± 0.25) years was recruited. Physical activity was assessed over 7 consecutive days by using pedometers to determine step counts (steps/day). Accrued anthropometric data included height, mass, and BMI. Data were compared with ANOVA to determine any significant differences between age and sex groups and the part of the week (weekday/weekend); intergroup differences were evaluated with Fisher's LSD test. A < 0.05 level of significance was adopted for all statistical tests. Results. No significant differences were found between the age groups (6- and 7-year olds). Physical activity over the 7-day period was significantly greater in the boys (13318 ± 2354 steps/day) than girls (12300 ± 2750 steps/day). Mean weekday step counts were greater among boys (13800 ± 2458 steps/day) than girls (12587 ± 2802 steps/day); this difference was statistically significant. Mean weekend steps were 12112 ± 3467 and 11579 ± 3930 steps/day for the boys and girls, respectively. Mean weekday steps were significantly greater (p < 0.001) than mean weekend steps in both groups. The recommendation of 12000 steps/day was met by 60.6% of the sample (69.0% boys, 51.4% girls). Conclusions. Sex differences in physical activity patterns were observed in the sample of preschool children. Boys, compared with girls, were characterized with a higher physical activity level on both weekdays and weekend days. Physical activity for both sexes was lower on weekend days than weekdays. The results indicate the need for improved health literacy among parents on current recommended physical activity guidelines and the suitability of a pedometer-based assessment method.
Key words: physical activity, pedometers, preschool children
Purpose. Sedentary behavior has been identified as a risk factor for chronic non-communicable diseases. This study identified the prevalence of excessive TV viewing time during the week and weekend and associated factors in adolescents living in a small urban and rural area. Methods. A cross-sectional study involving 283 students (aged 10–19 years) from Brazil was conducted in 2010. Data on TV viewing time and sociodemographic information were collected by questionnaires, cardiorespiratory fitness was evaluated by the 20-m shuttle run test, and anthropometric characteristics were obtained by measuring waist circumference and skinfold thickness. Statistical analysis involved binary logistic regression. Results. The prevalence of excessive TV viewing time (> 2 h) was 76.7% during on weekdays and 78.4% on the weekend. Adolescents aged 10–12 years (OR = 6.20; 95% CI = 2.91, 13.19; p < 0.001) and 13–15 years (OR = 2.57; 95% CI = 1.28, 5.18; p = 0.008) were more exposed to excessive TV viewing time during the week. No associations were found for excessive TV viewing time on the weekend. Conclusions. Approximately 8 in 10 adolescents presented excessive TV viewing time; excessive TV viewing time during the week was associated with age.
Key words: sedentary lifestyle, television, behavior, school health
Purpose. The objective of this study was to determine the relationships of peak oxygen uptake (VO2peak), power at O2peak and power at the anaerobic threshold (AT) with national ranking in a sample of British high performance junior surfers. Methods. Eighteen male surfers (aged 15.4 ± 1.4 years) from the British Junior Surfing team were tested for O2peak and AT using an adapted kayak ergometer; national ranking was used to indicate performance level. The AT was identified as the point at which E/ O2 started to rise without a concomitant increase in E/VCO2. Spearman’s rank (rs) and partial correlations (rp) controlling for age were used to identify the relationships between the physiological variables and national ranking. Results. Mean O2peak was 3.1 ± 0.5 l · min–1 (47.7 ± 7.2 ml · kg–1 · min–1) and mean AT occurred at 48.1 ± 12.2 W. There were significant correlations between national ranking and power at O2peak (rs = –0.549, p = 0.028), power at AT (rs = –0.646, p = 0.009), and age (rs = –0.579, p = 0.012). Significant partial correlations were established controlling for age between national ranking and power at O2peak (rp = –0.839, p = 0.000) and power at AT (rp = –0.541, p < 0.046). Conclusions. The power outputs associated with VO2peak and AT were significantly related to surfer ranking in this sample. However, due to the low coefficient of determination associated with the AT/ranking relationship, AT does not discriminate well between the ranking of surfers. These findings support the inclusion of power at O2peak in assessment batteries for junior competitive surfers.
Key words: physiology, sport, surfer, fitness, testing
Purpose.The purpose of the study was to assess anaerobic endurance in volleyball players through repeated vertical jump performance under quiet and noisy conditions. Methods. A group of 12 female players aged 19–28 year completed six sets of eight standing vertical jump jumps; jump height and heart rate before and after the protocol were measured in quiet and noisy (fan cheering) conditions. Results. Maximum and minimum vertical jump heights were higher and intragroup differences were smaller in noisy than quiet conditions. Conclusions. Vertical jump testing, a measure of physical activity typical of volleyball, is suitable for monitoring training effects. The influence of noise typical during volleyball matches had a positive effect on player performance and anaerobic endurance.
Key words: vertical jump, anaerobic endurance, volleyball
Purpose. The aim of the study was to establish the respiratory response to unloaded cycling at different cadences. Methods. Eleven healthy participants performed a maximal graded exercise test on a cycle ergometer to assess aerobic fitness (maximal oxygen consumption: 46.27 ± 5.41 ml · min–1 · kg–1) and eight 10-min unloaded pedaling (0 W) bouts at a constant cadence (from 40 to 110 rpm). Respiratory data were measured continuously during each effort and then averaged over 30 s. Blood samples were collected before and 2 min after each effort to monitor changes in acid–base balance. Results. The efforts were performed at an intensity of 16.5–37.5% VO2peak. Respiratory response was not differentiated in cadences of 40, 50, 60 rpm. From 70 rpm, an increase in cadence was significantly associated with increased minute ventilation (F = 168.11, p < 0.000) and oxygen consumption (F = 214.86 p < 0.000) and, from 80 rpm, respiratory frequency (F = 16.06, p < 0.001) and tidal volume (F = 54.67, p < 0.000). No significant changes in acid-base balance were observed as a result of difference cadences. Conclusions. Unloaded cycling at a cadence of 70 rpm or above has a significant effect on respiratory function and may be associated with the involvement of large muscle ergoreceptors (mechanoreceptors) stimulated by the frequency of muscle contractions.
Key words: breathing pattern, cycling, work rate, ergoreceptors
University School of Physical Education in Wrocław
al. I. J. Paderewskiego 35
51-612 Wrocław, Poland