bluuebunny/crossref_metadata_2025 huggingface dataset:
A Preliminary Study of the Effects of Verbal Motivation on Maximal Isokinetic Torque Production in Children with Varying Personality Types
Authors: McWhorter J. Wesley , Landers Merrill , Wallmann Harvey , Altenburger Beth
Published: August 2016

This study investigated the effects of verbal motivation on isokinetic peak torque knee extension in children with two distinct personality types (introvert versus extrovert). The subjects were tested in three groups without verbal motivation, with verbal motivation from the tester, and with verbal motivation from the tester and the other participants. A 2 − 3 mixed ANOVA was significant for interaction (p < .001). Post-hoc testing for the introverted group revealed that scores without verbal motivation were significantly higher than with verbal motivation, and the extroverted group scores were higher with verbal motivation. T tests revealed that the extroverted group performed significantly better than the introverted group with verbal motivation (p < .05). Results suggest that verbal motivation has a varying effect on isokinetic torque generating capacity in children with different personality types.
Sedentary Behavior, Not TV Viewing, Predicts Physical Activity among 3- to 7-Year-Old Children
Authors: Jago Russell , Baranowski Tom , Thompson Debbe , Baranowski Janice , Greaves Kathryn A.
Published: August 2016

Little information about relationships between the physical activity and sedentary behaviors of young children is available in the literature. We therefore examined how sedentary behaviors, TV watching, and encouragements and discouragements for activity were associated with physical activity (as measured by observation and heart-rate monitoring) among a tri-ethnic cohort of 149 three- to four-year-old children, which we followed for three years. The results showed that sedentary behavior predicted observed activity in Years 2 and 3 (r = −.672 and −.831, respectively, R2 = .577 and .775, respectively). Similar results were obtained for heart rate monitoring. Reducing the time children spend in sedentary behavior might result in increased physical activity.
Obesity, Physical Activity, Computer Use, and TV Viewing in Portuguese Adolescents
Authors: Mota Jorge , Ribeiro José , Santos Maria Paula , Gomes Helena
Published: August 2016

This study aimed to examine the relationship between obesity status (body mass index: BMI) and physical and sedentary activities in adolescents. The sample comprised 230 girls and 220 boys (14.6 years old, SD = 1.6). Physical Activity (PA) was assessed by a questionnaire. Sedentary behaviors, such as TV viewing, computer use, and commuting to and from school were analyzed. Participants were categorized as nonobese or overweight/obese according to age-adapted BMI. No significant differences were found in relation to PA characteristics or in TV watching on weekdays vs. weekends. Nonobese participants spent significantly less time using computers on weekends (p = .04) and weekdays (p = .025) than their overweight/obese counterparts. Logistic regression analysis showed that those who used computers on weekdays more than 4 hrs per day were likely (odds ratio: 5.79; p < .003) to be overweight or obese. This study identified a relationship between computer use, but not physical activity or TV viewing, and weight status among Portuguese adolescents.
Normal Physiological Characteristics of Elite Swimmers
Authors: Wells Gregory D. , Schneiderman-Walker Jane , Plyley Michael
Published: August 2016

The purpose of this research was to develop a comprehensive normative database of the physiological characteristics of elite swimmers. Data were obtained from 195 elite swimmers (89 males and 106 females) ages 12 to 18 years. Six protocols were used to measure variables in the following categories: descriptive characteristics, cardiovascular, respiratory, strength and power, body composition, and anthropometry. Significant effects of gender and age were identified for a number of variables. These data could be used for the physiological assessment and talent identification of swimmers in comparison with other populations.
Participation in Organized Youth Sport as a Predictor of Adult Physical Activity: A 21-Year Longitudinal Study
Authors: Telama Risto , Yang Xiaolin , Hirvensalo Mirja , Raitakari Olli
Published: August 2016

The aim of this study was to investigate how participation in organized competitive youth sport predicts adult physical activity. A random sample of 2,309 boys and girls ages 9–18 years participated in the Cardiovascular Risk in Young Finns Study in 1980, and 1,606 (70%) of them again in 2001. Physical activity was measured using a short, validated questionnaire. The results showed that participation in youth sport, and persistent participation in particular, significantly predicted adult physical activity. Participation in sport competitions increased the probability of high activity in adulthood more among males than females.
Acculturation Is Associated with Higher VO2max in Overweight Hispanic Children
Authors: Crespo Noé C. , Ball Geoff D.C. , Shaibi Gabriel Q. , Cruz Martha L. , Weigensberg Marc J. , Goran Michael I.
Published: August 2016

Acculturation has been implicated to be associated with physical activity (PA) behaviors in adults; little is known, however, with respect to the pediatric population. The purpose of this study was to determine whether cardiorespiratory fitness (VO2max) and/or PA were associated with acculturation status in overweight Hispanic children. In a sample of 144 children 8–13 years old, acculturation status was determined by place of birth: foreign born (n = 17), 1st generation (n = 101), or 2nd/3rd generation (n = 26), and by questionnaire: less assimilated (n = 76) or more assimilated (n = 34). VO2max was measured using a treadmill protocol, PA was assessed by questionnaire, and body composition by DEXA. ANOVA and ANCOVA were used to determine unadjusted and adjusted group differences, respectively. After adjusting for covariates, the 2nd/3rd generation group had significantly higher VO2max compared with the 1st generation group: 2.26 ± 0.20 L/min vs. 2.15 ± 0.19 L/min, p = .03. No differences were noted for PA, however. Acculturation to the U.S. is associated with higher VO2max in overweight Hispanic children. Longitudinal analyses are needed to determine whether these fitness differences confer protective health effects in this at-risk population.
Linking Physical Activity and Aerobic Fitness: Are We Active Because We Are Fit, or Are We Fit Because We Are Active?
Authors: Kemper Han C.G. , Koppes Lando L.J.
Published: August 2016

The purpose of this study was to test the hypothesis that physical activity (PA), measured over a period of 23 years, is beneficial to aerobic fitness (VO2max) in boys and girls (13-36 years) who were enrolled in the Amsterdam Growth and Health Longitudinal Study (AGAHLS). PA was measured using a standardized activity interview. VO2max was assessed directly with a maximal running test on a treadmill. To assess the longitudinal relationship between PA and VO2max, different longitudinal analyses were carried out over different age periods, correcting for various confounders such as lifestyle parameters, biological parameters, and initial VO2max. Highly significant relationships (p < .05) were observed between PA and VO2max in four of the five analyses. However, in an autoregression analysis, when current PA has been related to the future change in VO2max, the results are not any more significant (p > .05). Analysis of the data of PA and VO2max from the AGAHLS population does not fully support the hypothesis that PA affects VO2max.
Development of the Habitual Activity Estimation Scale for Clinical Research: A Systematic Approach
Authors: Hay John A. , University Brock , Cairney John
Published: August 2016

An understanding of the habitual physical activity levels of children with chronic disorders is an important consideration relevant to both treatment and clinical monitoring (8). However, a feasible and useful tool for measuring the physical activity levels of children with chronic illness in clinical settings is not readily available. In this article, we review the development and initial psychometric testing (i.e., construct and reliability) of the Habitual Activity Estimation Scale (HAES), a measure developed for use in clinical research. A summary of these investigations suggests that the HAES appears both valid and reliable as a measure of activity in pediatric populations.
Correlates of Structured and Unstructured Activity among Sufficiently Active Youth and Adolescents: A New Approach to Understanding Physical Activity
Authors: Spink Kevin S. , Shields Christopher A. , Chad Karen , Odnokon Patrick , Muhajarine Nazeem , Humbert Louise
Published: August 2016

The present study examines whether the correlates of physical activity relevant to sufficiently active youth and adolescents differed as a function of type (structured or unstructured) of physical activity. Participants completed measures of physical activity and activity correlates. The most frequently cited correlates were enjoyment, friends’ participation, and friends’ support. Significant differences were found across type of activity for enjoyment, perceived competence, parental support, coaches’ support, and friends’ participation. The results provide insight into the correlates of physical activity in this population and provide preliminary evidence that different correlates may be associated with different activities.
Social-Psychological and Physical Environmental Factors in Groups Differing by Levels of Physical Activity: A Study of Scottish Adolescent Girls
Authors: Whitehead Sarah H. , Biddle Stuart J.H. , O’Donovan Toni M. , Nevill Mary E.
Published: August 2016

Few studies have addressed factors influencing Scottish adolescent girls’ participation in physical activity (PA). Participants (N = 352) aged 11 to 16 years completed surveys measuring PA participation and potential social-psychological and physical-environmental correlates. Data were analyzed separately by two age groups (11-13 and 14-16 years). For younger girls, mother’s participation, perceived importance, and home equipment use were higher among those higher in PA. For older girls, perceived importance, home equipment use, neighborhood perceptions, and use and enjoyment of local facilities were higher among girls higher in PA. It seems that older girls place less importance on significant others and move toward autonomy away from the home.
What Does the Animal Model Teach Us about the Effects of Physical Activity on Growing Bone?
Authors: Forwood Mark R.
Published: August 2016

Experiments to design physical activity programs that optimize their osteogenic potential are difficult to accomplish in humans. The aim of this article is to review the contributions that animal studies have made to knowledge of the loading conditions that are osteogenic to the skeleton during growth, as well as to consider to what extent animal studies fail to provide valid models of physical activity and skeletal maturation. Controlled loading studies demonstrate that static loads are ineffective, and that bone formation is threshold driven and dependent on strain rate, amplitude, and duration of loading. Only a few loading cycles per session are required, and distributed bouts are more osteogenic than sessions of long duration. Finally, animal models fail to inform us of the most appropriate ways to account for the variations in biological maturation that occur in our studies of children and adolescents, requiring the use of techniques for studying human growth and development.
Test-Retest Reliability of Eurofit Physical Fitness Items for Children with Visual Impairments
Authors: Houwen Suzanne , Visscher Chris , Hartman Esther , Lemmink Koen A.P.M.
Published: August 2016

The purpose of this study was to examine the test-retest reliability of physical fitness items from the European Test of Physical Fitness (Eurofit) for children with visual impairments. A sample of 21 children, ages 6-12 years, that were recruited from a special school for children with visual impairments participated. Performance on the following physical fitness items was measured on two test sessions with 4 weeks in between: sit-and-reach, standing broad jump, handgrip, sit-ups, bent-arm hang, and 20-m multistage shuttle run. The 10 × 5-m shuttle run was replaced by a 5 × 10-m shuttle run. Intraclass correlations ranged from .63 to .91, indicating moderate-to-excellent reliability. However, systematic differences between test and retest were found for the sit-and-reach, bent-arm hang, and the modified 5 × 10-m shuttle run items. The results indicate that for most items, test-retest reliability was satisfactory, but that improvements need to be made to the test protocols of the sit-and-reach, bent-arm hang, and the 5 × 10-m shuttle run items to ensure test-retest reliability.
Secular Changes in Anaerobic Test Performance in Australasian Children and Adolescents
Authors: Tomkinson Grant R. , Hamlin Michael J. , Olds Timothy S.
Published: August 2016

Secular changes in anaerobic fitness test performance in healthy 6- to 17-year-old Australasians were examined by meta-analysis of 232,564 power- and speed-test performances between 1960 and 2002. Overall, power-test performance improved at a rate of +0.05% [95% confidence interval (CI) = +0.01% to +0.09%] per annum, and speed at +0.04% (CI = +0.02% to +0.06%) per annum. Results indicate that anaerobic-fitness-test performances have remained relatively stable in Australasian children and adolescents in recent decades.
Reliability of a Field and Laboratory Test of Repeated Sprint Ability
Authors: Oliver Jonathan L. , Williams Craig A. , Armstrong Neil
Published: August 2016

The purpose of this study was to assess the reliability of a field and a laboratory test of repeated sprint ability (RSA). Twelve adolescent boys (15.3 ± 0.3 years) completed five trials of both a field RSA test (7 × 30 m sprints) and a laboratory RSA test (7 × 5 s sprints) performed on a nonmotorized treadmill. Mean coefficients of variation (CV) calculated across all trials were < 2.7% for field sprint times, and, in the laboratory, < 2.9% for velocity and < 8.4% for power output. Fatigue indices (FI) calculated from data in both environments exhibited mean CVs > 23%. The inconsistency in the FIs resulted from the mathematical procedures used in the FI calculation methods. Based on the reliability scores, it was concluded that results obtained from measured performance variables in the field and laboratory, and not calculated FIs, should be used to report RSA.
Physical Activity Patterns of Singaporean Adolescents
Authors: Lee Kok Sonk , Trost Stewart G.
Published: August 2016

The purpose of this study was to document the level of physical activity and sedentary behavior in a representative sample of Singaporean adolescents. A random sample of 1,827 secondary school students from six secondary schools (929 boys, 898 girls, mean age 14.9 ± 1.2 yr) completed the Three-Day Physical Activity Recall (3DPAR) self-report instrument. Approximately 63% of Singaporean high school students met current guidelines requiring 60 min of moderate to vigorous physical activity daily. Just over half (51.6%) met the guideline calling for regular vigorous physical activity. Across all grade levels, boys were consistently more active than girls. More than 70% of Singaporean high school students exceeded the recommended 2 hours per day of electronic media use. Collectively, these findings suggest that a significant proportion of Singaporean adolescents are not sufficiently active and are in need of programs to promote physical activity and decrease sedentary behavior.
The Relationship between Fundamental Motor Skills and Outside-School Physical Activity of Elementary School Children
Authors: Raudsepp Lennart , Päll Peep
Published: August 2016

The purpose of the present study was to examine the association between fundamental motor skill development and various types of outside-school physical activity. Outside-school physical activity of 133 elementary schoolchildren was measured using a modified observational method validated by O’Hara et al. (18) and Caltrac accelerometers (Hemokinetics, Madison, Wisconsin). Developmental level of overhand throwing and jumping was assessed using total-body developmental sequences. The results revealed that developmental levels of both overhand throwing and jumping were significantly correlated with the skill-specific physical activity (r = .44 and .55 for overhand throwing and jumping, respectively). Caltrac score was not significantly related to jumping and overhand throwing skills. Skill-specific physical activities accounted for 20% of the variance (adjusted R2) in overhand throwing and 17% of the variance in jumping performance. Findings supported the hypothesis that developmental level of fundamental motor skills would be related with skill-specific outside-school physical activity but not with general level of physical activity of elementary schoolchildren.
Psychometric Properties of Two Systematic Observation Techniques for Assessing Physical Activity Levels in Children with Mental Retardation
Authors: Taylor Christina A. , Yun Joonkoo
Published: August 2016

This study examined the psychometric properties of the System for Observing Fitness Instruction Time (SOFIT) and the Children’s Activity Rating Scale (CARS) for use with children with mental retardation (MR). Eleven children with MR were videotaped while participating in a university-based community outreach program. Actiwatch accelerometers were used as the criterion measure. Results indicated that SOFIT and CARS both demonstrated adequate levels of generalizability (ϕ= 0.98 and 0.75), but a low concurrent validity coefficient for SOFIT (r = .10) and a moderate level of validity coefficient for CARS (r = .61) were observed. CARS demonstrates stronger validity evidence than SOFIT, but it is important to have sufficient rater training before using CARS for measuring physical activity level of children with MR.
Student and Parent Self-Reported Changes in Physical Activity Behavior while Wearing an Unsealed Pedometer
Authors: Beets Michael W. , Eilert Arissa G. , Pitetti Kenneth H. , Foley John T.
Published: August 2016

Child-parent pairs (n = 109) completed a questionnaire assessing whether changes in normal physical activity levels occurred (child) or were observed (parent) when the children wore a pedometer for 7 days. Over two-thirds of the children (78.5%) and almost half of the parents (47.3%) indicated an increase in the child’s normal physical activity. Reduced television viewing (75.2%) and increased outdoor play on the weekend (35.8%) were the most frequently reported means of behavior change as reported by the children and parents, respectively. Results indicate that both children and parents perceive a reactive effect to wearing an unsealed pedometer.
Analysis of Swimming Performance from Physical, Physiological, and Biomechanical Parameters in Young Swimmers
Authors: Jürimäe Jaak , Haljaste Kaja , Cicchella Antonio , Lätt Evelin , Purge Priit , Leppik Aire , Jürimäe Toivo
Published: August 2016

The purpose of this study was to examine the influence of the energy cost of swimming, body composition, and technical parameters on swimming performance in young swimmers. Twenty-nine swimmers, 15 prepubertal (11.9 ± 0.3 years; Tanner Stages 1−2) and 14 pubertal (14.3 ± 1.4 years; Tanner Stages 3−4) boys participated in the study. The energy cost of swimming (Cs) and stroking parameters were assessed over maximal 400-m front-crawl swimming in a 25m swimming pool. The backward extrapolation technique was used to evaluate peak oxygen consumption (VO2peak). A stroke index (SI; m2 · s−1 · cycles−1) was calculated by multiplying the swimming speed by the stroke length. VO2peak results were compared with VO2peak test in the laboratory (bicycle, 2.86 ± 0.74 L/min, vs. in water, 2.53 ± 0.50 L/min; R2 = .713; p = .0001). Stepwise-regression analyses revealed that SI (R2 = .898), in-water VO2peak (R2 = .358), and arm span (R2 = .454) were the best predictors of swimming performance. The backward-extrapolation method could be used to assess VO2peak in young swimmers. SI, arm span, and VO2peak appear to be the major determinants of front-crawl swimming performance in young swimmers.
Relationship of Fitness, Fatness, and Coronary-Heart-Disease Risk Factors in 12- to 13-Year-Olds
Authors: Thomas Non-Eleri , Cooper Stephen-Mark , Williams Simon P. , Baker Julien S. , Davies Bruce
Published: August 2016

The purpose of this study was to examine relationships between aerobic fitness (AF), fatness, and coronary-heart-disease (CHD) risk factors in 12- to 13-year-olds. The data were obtained from 208 schoolchildren (100 boys; 108 girls) ages 12.9 ± 0.3 years. Measurements included AF, indices of obesity, blood pressure, blood lipids and lipoproteins, fibrinogen, homocysteine, and C-reactive protein. An inverse relationship was found between AF and fatness (p < .05). Fatness was related to a greater number of CHD risk factors than fitness was (p < .05). Further analysis revealed fatness to be an independent predictor of triglyceride and blood-pressure levels (p < .05). Our findings indicate that, for young people, fatness rather than fitness is independently related to CHD risk factors.
Muscle Function in Saudi Children and Adolescents: Relationship to Anthropometric Characteristics during Growth
Authors: Almuzaini Khalid S.
Published: August 2016

The main purpose of the present study was to determine isokinetic strength and endurance, isometric strength, and anaerobic power for untrained healthy Saudi children and adolescents. The secondary purpose was to evaluate the effects of age in relation to anthropometric characteristics on strength and anaerobic performances. Forty-four (untrained) 11- to 19-year-old boys were grouped by age: 11-13 years, 14–16 years, and 17–19 years. All participants underwent anthropometric measurements, a flexibility test, a vertical jump test, a grip strength test, isokinetic strength measurements (Cybex Norm), and a Wingate anaerobic power test. Oneway ANOVA results indicated age-related increases in muscle strength and power. High correlation coefficients that were found among age and strength and anaerobic power indices almost disappeared when fat-free mass (FFM) was controlled for, indicating that the amount of variance in these indices that was explained by age is mostly shared by FFM. In addition, stepwise linear regression models indicated that FFM was the main predictor of strength and power performances. Thus, FFM was the best scaling variable for body size when comparing these age groups of Saudis. Until wide-range normal representative values for isokinetic strength and anaerobic power for Saudi children and adolescents are available, the present study’s results can serve as a reference for these indices.
Energy Expended Playing Video Console Games: An Opportunity to Increase Children’s Physical Activity?
Authors: Maddison Ralph , Mhurchu Cliona Ni , Jull Andrew , Jiang Yannan , Prapavessis Harry , Rodgers Anthony
Published: August 2016

This study sought to quantify the energy expenditure and physical activity associated with playing the “new generation” active and nonactive console-based video games in 21 children ages 10–14 years. Energy expenditure (kcal) derived from oxygen consumption (VO2) was continuously assessed while children played nonactive and active console video games. Physical activity was assessed continuously using the Actigraph accelerometer. Significant (p < .001) increases from baseline were found for energy expenditure (129–400%), heart rate (43–84%), and activity counts (122–1,288 versus 0–23) when playing the active console video games. Playing active console video games over short periods of time is similar in intensity to light to moderate traditional physical activities such as walking, skipping, and jogging.
The Efficacy of Exercise as an Intervention to Treat Recurrent Nonspecific Low Back Pain in Adolescents
Authors: Jones Michelle , Stratton Gareth , Reilly Tom , Unnithan Vishwanath
Published: August 2016

The purpose of this study was to evaluate the efficacy of a specific 8-week exercise rehabilitation program as an intervention to treat recurrent nonspecific low back pain in adolescents. A randomized controlled trial involving 54 adolescents (14.6 ± 0.6 years) who suffered from recurrent nonspecific low back pain participated in either the exercise rehabilitation program or a control condition. Pre- and postintervention measures of low back pain status and biological risk indicators were taken. Two-way mixed ANOVA was conducted and significance was set at p < .01. Significant improvement was noted in the exercise rehabilitation group for perceived severity of pain (effect size 1.47) and number of occasions missing physical activity (effect size 0.99). Significant improvement in the exercise rehabilitation group for sit-and-reach performance, hip range of motion, lumbar sagittal mobility (modified Schöber), and number of sit-ups in 60 s were also identified. In conclusion, the specific exercise program appeared to provide positive benefits for adolescents suffering from recurrent nonspecific low back pain. Further evaluation is required to evaluate the effectiveness of the exercise rehabilitation program in relation to other interventions and to assess the long-term effectiveness.
Exercise Training and Cardiovascular Risk Factors in Type 1 Diabetic Adolescent Girls
Authors: Heyman Elsa , Toutain Christelle , Delamarche Paul , Berthon Phanélie , Briard David , Youssef Hala , DeKerdanet Marc , Gratas-Delamarche Arlette
Published: August 2016

Sixteen postmenarcheal Type 1 diabetic adolescent girls were randomized into training (involving aerobic and strength exercises) and nontraining groups. Body composition (skinfold thickness), aerobic fitness (PWC170), plasma lipids, serum apolipoproteins, lipoprotein(a), leptin, and adiponectin were assessed before and after the 6-month period. After the 6-month period, fat mass and leptin increased significantly in the nontraining group but not in the training group. Conversely, in the latter group, fat-free mass increased (P < .01). Moreover, PWC170 improved and apolipoproteinB:apolipoproteinA-1 ratio decreased with physical training (P < .05). Thus, physical training reduces cardiovascular risks and the increase of insulin resistance risk factors in diabetic adolescent girls.
Effect of Screen-Based Media on Energy Expenditure and Heart Rate in 9- to 12-Year-Old Children
Authors: Straker Leon , Abbott Rebecca
Published: August 2016

This study compared the cardiovascular responses and energy costs of new and traditional screen based entertainments, as played by twenty 9- to 12-year-old children. Playing traditional electronic games resulted in little change to heart rate or energy expenditure compared with watching a DVD. In contrast, playing an active-input game resulted in a 59% increase in heart rate (p < .001) and a 224% increase in energy expenditure (p < .001) for boys and girls. The average heart rate of 130 bpm and energy expenditure of 0.13 kcal · min−1 · kg−1 achieved during active-input game use equates with moderate intensity activities such as basketball and jogging. Active-input electronic games might provide children with opportunities to engage with technology and be physically active at the same time.
Heart Rate Determination of Anaerobic Threshold in Children
Authors: Gaisl Georgine , Hofmann Peter
Published: August 2016

Ethical and logistical limitations preclude the routine determination of anaerobic threshold in children by invasive measurement of blood lactate concentrations or ventilatory parameters. A noninvasive field test developed by Conconi can be used to determine anaerobic threshold through analysis of the heart rate curve during increased exercise workloads. Although this test was initially evaluated in adult athletes, recent data indicate that the Conconi test is applicable to children in both laboratory and field settings. Close correlation with lactate-derived anaerobic threshold appears to be possible when utilizing standard testing protocols.
Acute Intraarterial Blood Pressure Response to Bench Press Weight Lifting in Children
Authors: Nau Karen L. , Katch Victor L. , Beekman Robert H. , Dick Macdonald
Published: August 2016

Intraarterial blood pressure (BP) response to bench press weight lifting (WL) was evaluated in 11 children. Aortic systolic and diastolic pressures and heart rate (HR) were measured during WL. Baseline systolic and diastolic pressures were 120 and 81 mmHg, and HR was 86 bpm. Subjects lifted to voluntary fatigue weights equaling 60, 75, 90, and 100% of their predetermined one-repetition maximum (1RM). For each weight lifting condition, BP and HR increased as more repetitions were completed. Peak systolic pressure was 168, 177, 166, and 162 mmHg, peak diastolic pressure was 125, 139, 133, and 130 mmHg, and peak heart rate was 142, 148, 142, and 139 bpm at 60, 75, 90, and 100% 1RM, respectively. Peak BP and HR were greater during WL than rest but did not differ between conditions. The relative BP response to WL in children was similar to adult values. For all conditions, pressures increased as more repetitions were completed. It was concluded that peak pressures occur at voluntary fatigue, independent of the combination of resistance and repetitions used to achieve fatigue.
Intensity of Sports Participation in Circumpubertal Children
Authors: Naughton Geraldine , Carlson John
Published: August 2016

The heart rate intensity during 20 minutes of sports participation by circumpubertal children was monitored several times over a season. The competitive games’ mean absolute heart rates for basketball, badminton, netball, and tennis were 170, 159, 168, and 162 bts·min−1 (or 72, 75, 69, and 67% of heart rate maximum), respectively. The mean abolute heart rates for 20 minutes of participation under practice conditions for badminton, basketball, netball, and tennis were 149, 157, 144, and 135 bts·min−1, or 73, 75, 69, and 67% of heart rate maximum. At the 0.05 level of probability there was a significant difference between the heart rate intensities under competitive game and practice situations in the badminton, netball, and tennis groups. The difference between intensities of competitive games and practices was nonsignificant in the basketball players. The study concluded that participation in practice and game conditions was positive in providing the potential for a training stimulus.
Muscular Strength and Power in Elite Young Male Runners
Authors: Thorland William G. , Johnson Glen O. , Cisar Craig J. , Housh Terry J. , Tharp Gerald D.
Published: August 2016

This study assessed strength and muscular power of elite young male runners in order to determine the relationship of these characteristics to age and specialization in either sprint or middle distance events. Forty-eight national junior-level sprint and middle distance runners were evaluated for isokinetic peak torque for leg extension as well as muscular power and fatiguability. Peak torque values were greater for the older runners and for the sprinters when measured at higher velocities. However, when adjusted for body weight, the peak torque values of the sprinters became significantly greater at all testing velocities. Muscular power values were also greater for the older runners, but event-related differences only appeared for peak power and mean power measures (being greater in the sprinters).
The Validity and Reliability of Fitness Tests for Children: A Review
Authors: Safrit Margaret J.
Published: August 2016

The measurement of physical fitness in children and youth has long been a topic of interest to physical educators, exercise scientists, health agencies, and private organizations dealing with sport and fitness. In recent years the focus on problems in measuring fitness has become more intense due to a number of factors, in particular the need for adequate surveillance studies and the perceived lack of fitness education in the schools. The purpose of this paper is to examine the scientific evidence that supports the use of measurement techniques for fitness evaluation. Physical fitness is described as a scientific construct that is multifaceted. A rationale is presented for the development of an operational definition of fitness that provides a basis for the identification of components of fitness to be measured. The latest versions of national fitness tests are described and compared, and evidence of the reliability and validity of the test batteries as well as individual subtests is summarized. Finally, several issues associated with fitness testing are discussed. These include the use of criterion referenced standards, the development of norms, and the use of fitness tests in a school setting. Although many improvements in tests and testing practices are noted, research is needed on a variety of problems.
Stride Frequency and Submaximal Treadmill Running Economy in Adults and Children
Authors: Unnithan Viswanath B. , Eston Roger G.
Published: August 2016

Previous studies have consistently shown that the body mass/relative oxygen cost of submaximal treadmill running is greater in children than in young adults. It has been suggested that the obligatory increased stride frequency in children might be at least partly responsible. This hypothesis was investigated by examining the association between stride frequency and oxygen demand characteristics in 10 aerobically fit prepubescent boys (ages 9-10 yrs) and 10 fit young men (ages 18-25 yrs) while running at fixed submaximal speeds on an electronically driven treadmill. The oxygen demand was higher at all running speeds in the boys’ group. To compensate for a shorter stride length, the boys demonstrated higher stride frequency at all speeds. To determine if the inferior running economy in the boys was partly due to the greater stride frequency, the relative oxygen demand per stride was compared between groups at all speeds. This value was similar in both groups. It is concluded that the apparently greater oxygen demand of running in boys may be due in part to the greater stride frequency required to maintain similar running speeds.
Exercise Correlates of Electrophysiologic Assessment of Sinus Node Function in Young Individuals
Authors: Bricker J. Timothy , Garson Arthur , Paridon Stephen M. , Vargo Thomas A.
Published: August 2016

This study evaluated prospective exercise correlates of sinus node function in young individuals. Subjects for this study were 25 children and young adults who required cardiac catheterization for a symptomatic arrhythmia. Measurements of sinus node function at elechophysiological catheterization were the sinus node recovery time (SNRT) and sinoatrial conduction time (SACT). Maximal exercise testing was performed using a Bruce treadmill protocol the day prior to cardiac catheterization. Exercise measurements included resting heart rate, peak heart rate, cardiac acceleration from rest to 3 minutes, from rest to 6 minutes, from rest to peak, and from 3 to 6 minutes, cardiac deceleration from peak to 1 minute postexercise, deceleration for each minute of recovery, recovery heart rates for each of 5 minutes postexercise, heart rate at which respiratory exchange ratio >1.0 and slope of the heart rate – VO2 curve. Exercise testing did not predict intracardiac measures of sinus node function either as a group (“normal” vs. “abnormal” groups) or individually.
Growth Plate Injury and Bone Growth: An Update
Authors: Caine Dennis J.
Published: August 2016

This literature review reveals an accumulating body of evidence indicating that growth disturbance associated with both chronic and acute growth plate injury occurs in young athletes and may be more prevalent than formerly believed. Skeletal complications resulting from these injuries may include progressive bone shortening, progressive deformity, joint incongruity, and arthritic sequelae. Against this background an increased concern for the welfare of young athletes is recommended. It is emphasized that back pain or pain around a joint in young athletes may be the symptom of significant growth plate changes that require accurate diagnosis, adequate treatment, and specific recommendations about return to activity. Suggestions are given for further research and prevention of growth plate injuries.
Timing Changes for Stance, Swing, and Double Support in a Recent Below-Knee-Amputee Child
Authors: Engsberg Jack R. , Tedford Kathy G. , Harder James A. , Mills Jocelyn P.
Published: August 2016

This investigation compared stance, swing, and double support times of a recent below-the-knee amputee (BKA) child’s gait with the gait of normal children and with that of experienced BKA children. Kinematic data were collected for 11 normal children, 2 experienced BKA children, and a novice BKA child. Results indicated there were significant differences between the steps of prosthetic and nonprosthetic limbs and between normals and BKAs. Initially the gait of the novice BKA differed from that of experienced BKAs. After 94 days the gait of the novice BKA was not significantly different from that of the experienced BKAs. It was concluded that since the structure and function of the prosthetic limb is not the same as normal, (a) it may be appropriate for the BKA child to have an asymmetrical gait pattern, and (b) rehabilitation may be directed toward teaching the recent BKA child to walk more like experienced BKAs than like normal children.
The Previously Low Birth Weight Infant: Fundamental Motor Skill Outcomes in the 5- to 9-Year-Old
Authors: Pohlman Roberta L. , Isaacs Larry D.
Published: August 2016

This preliminary investigation examined the potential effects of low birth weight on motor performance in children. Seventeen pairs of children were matched by age and placed in one of five age groups (5-9 years). One of each pair weighed 2,200 grams or less at birth (low birth weight, LBW) and the other weighed more than 2,200 grams at birth (normal birth weight, NBW). Three types of data were collected: motor development data, reaction time data, and anthropometric data. Nine paired t tests were performed. To control for alpha level inflation, the Bonferroni technique was employed. The two groups did not differ significantly in present body weight. Tests of gross motor development found the NBW group to be more advanced in both locomotor skills and object control skills. With regard to triceps skinfold, again the NBW group was found to have greater values. No other between-group measurements of body composition were significant. In addition, girls were significantly higher than boys in percent body fat. These preliminary results suggest the LBW children lag behind their NBW peers in the development of the basic fundamental motor skills.
Physiologic Comparison of Adolescent Female and Male Cross-Country Runners
Authors: Cunningham Lee N.
Published: August 2016

To compare the physiologic differences between adolescent male and female cross-country runners, 12 male and 12 female high school nonelite distance runners who had competed successfully at the All State 5-km championship cross-country meet were tested in the laboratory. Data were analyzed in relation to maximal oxygen consumption (VO2max), ventilatory threshold (VT), and running economy (RE). Male runners were taller, heavier, had less body fat, and ran faster by 2 minutes and 18 seconds than female runners. Running economy was similar between gender. VO2 at a 215 m•min−1 pace was 46.7 ml•kg−1•min−1 for male runners and 47.8 ml•kg−1•min−1 for female runners. At the VT, males demonstrated a higher VO2 and treadmill velocity than females. Heart rate, percent HR max, and percent VO2 max at the VT were not different between gender. Males demonstrated a higher VO2 max of 74.6 versus 66.1 ml•kg−1•min−1 than female runners. The fractional utilization of VO2 at race pace was not different between males (90%) and females (91%). In conclusion, the primary physiologic determinant for performance differences between nonelite, competitive male and female adolescent distance runners is associated with VO2 max.
Peak Oxygen Uptake and Physical Activity in 11- to 16-Year-Olds
Authors: Armstrong Neil , Balding John , Gentle Peter , Williams Joanne , Kirby Brian
Published: August 2016

The present study examined the relationship between peak V̇O2 and habitual physical activity in 11- to 16-year-old students. The peak V̇O2 of 111 girls and 85 boys was determined using treadmill or cycle ergometry. Habitual physical activity was estimated from minute-by-minute heart rate monitoring over three 12-hr periods during normal school days. Over half of the girls and one third of the boys failed to sustain a single 10-min period with their heart rate at or above 140 bpm. Only one boy sustained a daily 20-minute period with a heart rate at or above 160 bpm. During Saturday monitoring over 90% of the girls and 75% of the boys failed to sustain a single 10-min period with their heart rate at or above 140 bpm, and only one girl and four boys sustained a 20-min period with their heart rate at or above 160 bpm. No significant relationship was detected between peak V̇O2 and heart rate indicators of habitual physical activity. This study suggests that few children have periods of physical activity of sufficient intensity and duration to stress the cardiopulmonary system.
Cardiorespiratory Fitness and Risk Factors for Coronary Artery Disease in 8- to 15-Year-Old Boys
Authors: Kwee Anneke , Wilmore Jack H.
Published: August 2016

A sample of 399 boys, 8 to 15 years of age, underwent a comprehensive evaluation to determine the extent to which coronary artery disease (CAD) risk factors are related to an estimate of cardiorespiratory fitness. The boys were divided into four groups on the basis of their directly measured VO2max. Significant differences were found between fitness groups for relative body fat, plasma triglycerides, systolic and diastolic blood pressure, and systolic blood pressure divided by height, with the higher fitness groups exhibiting substantially lower values. When covariance analyses were conducted, adjusting for differences in age and relative body fat, the differences in blood pressure were no longer statistically significant. No differences were found between fitness groups for total cholesterol, HDL-C, LDL-C, or the ratio of HDL/TC. It is concluded that there is not a strong relationship between cardiorespiratory fitness and CAD risk factors in boys 8- to 15-years of age.
Relationship between Indicators of Fitness and Bone Density in Adolescent Brazilian Children
Authors: Fonseca Rômulo Maia Carlos , de França Nanci Maria , Van Praagh Emmanuel
Published: August 2016

The purpose of the current study was to investigate the relationship between health-related physical fitness and bone mineral density (BMD) in adolescents. One hundred forty-four adolescents (65 boys and 79 girls) between 15 and 18 years of age were recruited to this cross-sectional study. Subjects were evaluated in aerobic fitness, muscular fitness, flexibility, body composition, and maturation. BMD of the lumbar spine, total body, and proximal femur were measured by a dual-energy X-ray absorptionmeter. Pearson’s correlation and stepwise multiple regression analyses were used (p < .05). Lean body mass (LBM) and abdominal muscular fitness explained 35–40% of proximal femur BMD in whole group and boys’ total body BMD (43%); however, VO2max and LBM predicted girls’ total body BMD (23%). Lumbar spine BMD was predicted only by LBM for both genders (18% boys, 15% girls). In summary, lean body mass is the main predictor of bone mass during the end of adolescence, regardless of gender, whereas muscular fitness contributes more to bone mass among males than among females.
Bone Properties in Overweight Pre- and Early-Pubertal Boys
Authors: Falk Bareket , Braid Sarah , Moore Michael , O’Leary Deborah , Sullivan Phil , Klentrou Panagiota
Published: August 2016

The objective of this study was to assess bone strength using quantitative ultrasound (QUS, Sunlight Omnisense) in pre- and early-pubertal normal weight (NW, % body fat ≤20, n = 28), and overweight (OW, % body fat ≥25, n = 15) boys. Groups were similar in chronological and skeletal age, sexual maturity, sports participation, and calcium intake. Leisure-time physical activity was lower in OW boys. Radial speed of sound (SOS) was similar in the two groups. Tibial SOS, however, was significantly lower in OW compared with NW (3,554 ± 109 vs. 3,646 ± 71 m·s−1, respectively). Among pre- and early-pubertal boys, higher adiposity appears to be associated with lower bone SOS in the lower extremities.
Peak Oxygen Uptake in Children: Evaluation of an Older Prediction Method and Development of a New One
Authors: Arngrímsson Sigurbjörn Árni , Sveinsson Torarinn , Jóhannsson Erlingur
Published: August 2016

The purpose of this study was to validate an equation that has been used to predict peak oxygen uptake (VO2peak) and, if invalid, to develop a new equation predicting VO2peak from performance on a cycle ergometer test. Forty-five 9- and 15-year-old children underwent a VO2peak test and were randomized into developmental (DEV) and cross-validation (C-V) groups. The equation under validation, which requires knowledge of resting energy expenditure (REE), underestimated VO2peak (p < .05), but once adjusted with a new parameter calculated in DEV, it cross-validated well (rYY′ = .98, SE = .18 L · min−1). The accuracy of a new prediction equation built in DEV, not using REE, was confirmed in C-V (rYY′ = .98, SE = .17 L · min−1) and the slope and intercept were not different from the line of identity (p < .05). VO2peak in schoolchildren can be predicted with good accuracy from an equation based on the whole sample [VO2peak′ = −1.5986 + 0.0115 · (maximal power output) + 0.0109 · (mass) + 0.1313 · (gender) + 0.0085 · (maximal heart rate)].
Acute Affective Responses to Prescribed and Self-Selected Exercise Intensities in Young Adolescent Boys and Girls
Authors: Sheppard Kate E. , Parfitt Gaynor
Published: August 2016

This study examined the patterning of acute affective responses to prescribed and self-selected exercise intensities in a young adolescent population. Twenty-two young adolescents (13.3 ± .33 years) completed a maximal exercise test to identify ventilatory threshold (VT). Participants then completed two prescribed intensities (one set above and one below the VT) and a self-selected intensity. Pre-, during, and postexercise affective valence was measured. Results revealed that during exercise, affective valence assessed by the Feeling Scale (FS) remained positive in the self-selected and low-intensity conditions but declined in the high-intensity condition. Postexercise FS responses rebounded to preexercise levels, eradicating divergent trends that occurred during exercise.
Race Differences in Activity, Fitness, and BMI in Female Eighth Graders Categorized by Sports Participation Status
Authors: Sirard John R. , Pfeiffer Karin A. , Dowda Marsha , Pate Russell R.
Published: August 2016

The purpose of this study was to identify racial differences in physical activity (PA), fitness, and BMI in female 8th-grade sports participants and nonparticipants. Girls from 31 South Carolina middle schools (N = 1,903, 48% White; mean age = 13.6 ± 0.63) reported PA and previous year sports-team participation, completed a submaximal fitness test, and had height and weight measured. Sports team participation was positively associated with PA and negatively associated with television viewing and BMI, in a dose-response manner. Compared with Whites, African-Americans reported less PA and more television viewing, and had greater BMI scores. Whereas PA intervention programs that incorporate a sports-team component could benefit all girls, African-American girls could be specifically targeted because of their lower physical activity.