We investigated whether children with suspected Developmental Coordination Disorder (DCD+) demonstrate different physical fitness levels compared with their normal peers (DCD−). Randomly recruited Greek children (n = 177) were assessed for body mass index (BMI), flexibility (SR), vertical jump (VJ), hand strength (HS), 40m dash, aerobic power, and motor proficiency. ANCOVA revealed a motor proficiency (i.e., DCD group) effect for BMI (p < .01), VJ (p < .01), and 40m speed (p < .01), with DCD+ children demonstrating lower values than DCD−. Differences between DCD+ and DCD− were also obtained in log-transformed HS (p < .01). These findings suggest that intervention strategies for managing DCD should also aim at physical fitness increases.
Georgia D. Tsiotra, Alan M. Nevill, Andrew M. Lane and Yiannis Koutedakis
Rossana C. Nogueira, Benjamin K. Weeks and Belinda R. Beck
Our goal was to test the effect of a brief, novel bone- and fat-targeted exercise program on bone, muscle, and fat in healthy pre and peripubertal boys. We conducted a 10-min, 3/wk capoeira and jumping exercise intervention for 9 months with year 5 and 6 school boys. Anthropometrics, maturity, heart rate, blood pressure, maximal vertical jump, aerobic capacity and calcaneal broadband ultrasound attenuation and stiffness index (BUA and SI; Achilles, GE) were assessed. Bone, lean and fat tissue (DXA; XR800, Norland), and parameters of bone geometry (pQCT, XCT3000, Stratec) were measured from a subsample of 36 boys. Of 188 boys (10.6 ± 0.5 yr) who consented, 172 completed all testing; 104 exercisers (EX) and 68 controls (CON). 30 EX and 6 CON participants underwent DXA and pQCT measures. EX improved BUA (+4.3% vs. +2.1%, p = .035), waist circumference (+2.8% vs. +6.2%, p = .001), heart rate (-5.3% vs. +1.5%, p = .005), maximal vertical jump (+12.2% vs. −0.3%, p = .001) and estimated maximal oxygen consumption (+9.1% vs. +1.2%, p = .001) compared with CON. Three 10-min sessions of capoeira and jumping per week improved calcaneal bone and metabolic health of pre and peripubertal boys over the course of a school year with little disruption to the academic schedule.
Zandrie Hofman, Rolf Smeets, George Verlaan, Richard v.d. Lugt and Peter A. Verstappen
In a double-blind, randomized, placebo-controlled study, we investigated the effect of 8 weeks of supplementation with bovine colostrum (Intact™) on body composition and exercise performance (5 × 10-m sprint, vertical jump, shuttle-run test, and suicide test). Seventeen female and 18 male elite field hockey players, including players from the Dutch national team, received either 60 g of colostrum or whey protein daily. The 5 × 10-m sprint test performance improved significantly (p = .023) more in the colostrum group [0.64±0.09 s (mean ± SEM)] compared to the whey group (0.33±0.09 s). The vertical jump performance improved more in the colostrum group (2.1 ± 0.73 cm) compared to the whey group (0.32 ± 0.82 cm). However, this was not statistically significant (p = .119). There were also no significant differences in changes in body composition and endurance tests between the 2 groups. It is concluded that in elite field hockey players, colostrum supplementation improves sprint performance better than whey. However, there were no differences with regard to body composition or endurance performance.
Rachel A. Hildebrand, Bridget Miller, Aric Warren, Deana Hildebrand and Brenda J. Smith
Increasing evidence indicates that compromised vitamin D status, as indicated by serum 25-hydroxyvitamin D (25-OH D), is associated with decreased muscle function. The purpose of this study was to determine the vitamin D status of collegiate athletes residing in the southern U.S. and its effects on muscular strength and anaerobic power. Collegiate athletes (n = 103) from three separate NCAA athletic programs were recruited for the study. Anthropometrics, vitamin D and calcium intake, and sun exposure data were collected along with serum 25-OH D and physical performance measures (Vertical Jump Test, Shuttle Run Test, Triple Hop for Distance Test and the 1 Repetition Maximum Squat Test) to determine the influence of vitamin D status on muscular strength and anaerobic power. Approximately 68% of the study participants were vitamin D adequate (>75 nmol/L), whereas 23% were insufficient (75–50 nmol/L) and 9%, predominantly non-Caucasian athletes, were deficient (<50 nmol/L). Athletes who had lower vitamin D status had reduced performance scores (p < .01) with odds ratios of 0.85 on the Vertical Jump Test, 0.82 on the Shuttle Run Test, 0.28 on the Triple Hop for Distance Test, and 0.23 on the 1 RM Squat Test. These findings demonstrate that even NCAA athletes living in the southern US are at risk for vitamin D insufficiency and deficiency and that maintaining adequate vitamin D status may be important for these athletes to optimize their muscular strength and power.
Dennis-Peter Born, Billy Sperlich and Hans-Christer Holmberg
To assess original research addressing the effect of the application of compression clothing on sport performance and recovery after exercise, a computer-based literature research was performed in July 2011 using the electronic databases PubMed, MEDLINE, SPORTDiscus, and Web of Science. Studies examining the effect of compression clothing on endurance, strength and power, motor control, and physiological, psychological, and biomechanical parameters during or after exercise were included, and means and measures of variability of the outcome measures were recorded to estimate the effect size (Hedges g) and associated 95% confidence intervals for comparisons of experimental (compression) and control trials (noncompression). The characteristics of the compression clothing, participants, and study design were also extracted. The original research from peer-reviewed journals was examined using the Physiotherapy Evidence Database (PEDro) Scale. Results indicated small effect sizes for the application of compression clothing during exercise for shortduration sprints (10–60 m), vertical-jump height, extending time to exhaustion (such as running at VO2max or during incremental tests), and time-trial performance (3–60 min). When compression clothing was applied for recovery purposes after exercise, small to moderate effect sizes were observed in recovery of maximal strength and power, especially vertical-jump exercise; reductions in muscle swelling and perceived muscle pain; blood lactate removal; and increases in body temperature. These results suggest that the application of compression clothing may assist athletic performance and recovery in given situations with consideration of the effects magnitude and practical relevance.
Nathan J. Crockett and Michelle A. Sandrey
Few studies have evaluated the long-term effects of prophylactic ankle-brace use during a sport season.
To determine the effects of prophylactic ankle-brace use during a high school basketball season on dynamic postural control and functional tests.
Prospective repeated-measures design.
High school athletic facility.
21 healthy high school basketball athletes (13 girls, 8 boys).
The order of testing was randomized using the Star Excursion Balance Test (SEBT) for posteromedial (PM), medial (M), and anteromedial (AM) directions and 3 functional tests (FT) consisting of the single-leg crossover hop, single-leg vertical jump, and the single-leg 6-m hop for time at pre-, mid-, and postseason. After pretesting, the ankle brace was worn on both limbs during the entire 16-wk competitive basketball season.
Main Outcome Measures:
SEBT for PM, M, and AM and 3 single-leg FTs.
Dynamic postural control using the SEBT and the 3 FTs improved over time, notably from pretest to posttest. The left limb was different from the right limb during the single-leg vertical jump. Effect sizes were large for pretest to posttest for the 3 SEBT directions and 2 of the 3 FTs.
The 16-wk basketball prophylactic ankle-brace intervention significantly improved dynamic postural control and single-limb FTs over time.
Robert C. Weber and JoAnne Thorpe
The purpose of the study was to determine whether the technique of task variation with maintenance tasks interspersed is more effective than a constant task condition in a physical education setting in learning gross motor skills for severely disabled individuals. The subjects for the study included 28 males, 12 autistic and 16 severely mentally retarded students, ages 10 to 14 years. The design for this study was a pretest-posttest configuration with the I Can Assessment of Gross Motor Skills utilized to assess the basic skills of overhand throw, kick, vertical jump, slide, continuous bounce, and underhand roll. Results indicated that following a 6-week treatment period the task variation with maintenance tasks interspersed condition was significantly more effective at the .01 level in learning gross motor skills than a constant task condition. However, when autistic and severely mentally retarded individuals were compared, there were no significant differences.
Jennifer M. Medina McKeon, Craig R. Denegar and Jay Hertel
The purpose of this study was to formulate a predictive equation to discriminate males from females using static and dynamic lower extremity (LE) alignments. Twenty-four healthy adults volunteered to participate. Three-dimensional motion analysis was used to assess the kinematics of the right hip and knee during two functional tasks. Six measures of static LE alignment were also performed. Statistical comparisons were made between males and females for all variables. Static and dynamic variables that were significantly different by sex were entered into separate discriminant analyses for each task. The resulting equations were each able to correctly predict 87% of the subjects by sex. Fifty-eight percent and 55% of the variance was explained by sex for the vertical jump and plant & jump, respectively. The frontal plane hip angle was the best predictor of sex for both tasks. While there were statistically significant differences between the sexes for static measures of LE alignment, kinematic measures were better at discriminating between sexes.
James C. Radcliffe and Louis R. Osternig
Seventy subjects were tested for (a) percent body weight controlled (lowered and raised) by the lower extremities via parallel squat exercise, (b) maximum vertical jump-reach, and (c) maximal depth jump-reach from six heights ranging from 0.30 to 1.05 m. The results suggest that maximum parallel squat performance represents a small proportion (8%) of the variance contributing to controlling increasing depth jump heights and that specific improvement in jumping performance may be achieved by relatively small amplitude prestretch movements rather than large depth jump heights. The implications of the present findings for the use of depth jumping in conditioning and rehabilitative protocols are that (a) extreme care must be exercised in selecting jump heights, as there is considerable variability in individual tolerance to a given height, and (b) depth jumping should be contraindicated in cases where high impulse loads can disrupt healing tissue and, if it is used in postinjury situations, should be reserved for the end phase of rehabilitation.
John E. Kovaleski, Robert J. Heitman, Damon P.S. Andrew, Larry R. Gurchiek and Albert W. Pearsall IV
Isokinetic strength and functional performance are used to assess recovery after rehabilitation. It is not known whether low-speed closed-linear-kinetic isokinetic muscle strength correlates with functional performance.
To investigate the relationship between linear closed (CKC) and open (OKC) concentric isokinetic strength of the dominant lower-limb extensors and functional performance.
Thirty uninjured men and women (age = 20.9 ± 2.4 years).
Main Outcome Measures:
Peak CKC and OKC isokinetic strength and best score from a shuttle run for time, single-leg vertical jump, and single-leg hop for distance.
Neither lower-limb CKC nor OKC isokinetic strength measured at low speeds correlated highly with performance on the functional tasks of jumping, hopping, and speed/agility.
Although the basis of both closed and open isokinetic strength must be appreciated, they should not be the only determinants of functional performance.