Functional analysis of postural spinal and pelvic parameters using static and dynamic spinometry.

Background: Spinometry is a radiation-free method to three-dimensional spine imaging that provides additional information about the functional gait patterns related to the pelvis and lower extremities. This radiation-free technology uses the surface topography of the trunk to analyze surface asymmetry and identify bony landmarks, thereby aiding the assessment of spinal deformity and supporting long-term treatment regimes. Especially reliable dynamic spinometric data for spine and pelvis are necessary to evaluate the management of non-specific back pain. Research aim: This study aims to generate reliable dynamic spinometric data for spine and pelvis parameters that can serve as reference data for future studies and clinical practice. Methods: This study assessed 366 subjects (185 females) under static and 360 subjects (181 females) under dynamic (walking on a treadmill at 3 km/h and 5 km/h) conditions. The DIERS Formetric 4Dmotion® system uses stripes of light to detect the surface topography of the spine and pelvis and identifies specific landmarks to analyze the spine during standing and walking. Results: Relevant gender effects were calculated for lordotic angle (ηp2 = 0.22) and pelvic inclination (ηp2 = 0.26). Under static conditions, female subjects showed larger values for both parameters (lordotic angle: 41.6 ± 8.60°; pelvic inclination: 25.5 ± 7.49°). Regarding speed effects, three relevant changes were observed (sagittal imbalance: ηp2 = 0.74, kyphotic angle: ηp2 = 0.13, apical deviation: ηp2 = 0.11). The most considerable changes were observed between static condition and 3 km/h, especially for sagittal imbalance and lordotic angle. For these parameters, relevant effect sizes (d > 0.8) were calculated between static and 3 km/h for males and females. Concerning clinical vertebral parameters, only lordotic angle and pelvic inclination were correlated with each other (r = 0.722). Conclusion: This study generated a gender-specific reference database of asymptomatic individuals for static and dynamic spinometry. It demonstrated that the DIERS Formetric 4Dmotion® system could capture natural changes in static and dynamic situations and catalogue functional adaptations of spino-pelvic statics at different speeds. The lordotic angle is an indirect marker of pelvic inclination, allowing spinometry to identify individuals at risk even under dynamic conditions.

Associations between biological maturation, physical performance, postural control, and mathematical achievement in youth soccer players.

This investigation explored relationships between biological maturation, physical and academic performance in young male soccer players. Thirty-eight players (age: 9.79 ± 1.21 years; body mass index (BMI): 20.4 ± 2.39 kg/m2; body fat: 16.8 ± 2.21%) participated. Measures of anthropometry used for body mass, body fat percentage (%BF), and BMI as well. Postural control, 15 m sprint, squat jumps and counter-movement jumps (SJ, CMJ), and T-half test for change-of-direction (CoD) were parameters of physical performance. The grade point average (GPA) of mathematics determined academic attainment. Moore's equations were used to estimate their maturity status (PHV). Biological maturation was highly correlated with most (not 15 m sprint) physical and academic performance parameters, especially CMJ (r = -0.812) and mathematics (r = -0.781). Academic performance showed the largest relations to the jumping performance (CMJ: r = 0.771; SJ: r = 0.723). In contrast, anthropometric and fatness parameters were not relevantly (r ≥ 0.5) correlated with any other parameters. The largest correlations were calculated for sitting height vs. SJ (r = -0.408), sitting height vs. postural control (r = -0.355), leg length vs. postural control (r = -0.339). As a result, it is essential to take biological maturation inconsideration while assessing the physical and academic achievement of young soccer players. In consequence, soccer coaches and physical education (PE) teachers should be cognizant of the impact of biological maturity on physical and academic performance to assist fair and equal opportunities for achievement in young players.

Comparative Analysis of Physical Activity, Performance-Related Health, and Academic Achievements in 11-to-13-Year-Old Schoolchildren in Qatar.

Age-related differences in physical activity (PA), maturity status (PHV), physical performance (PP), and academic achievement (AA) among schoolchildren in Qatar were examined. Sixty-nine students from a school in Doha were categorized into three equal (n = 23) groups: 11-year-old students (U11; male: n = 14), 12-year-old students (U12: male: n = 7), and 13-year-old students (U13: male: n = 11). The testing process comprised a medicine ball throw, Stork balance test, hand grip strength test, the T-half test (PP), GPA in Arabic, mathematics, science (AA), International Physical Activity Questionnaire Short Form (PA), and Moore's equations (PHV). Relevant age-related differences (p < 0.001) were identified in mathematics, science, the T-half test, maturity, and arm span. Notably, differences between adjacent age groups were evident between U11 and U12, concerning arm span, maturity, mathematics, and science, and between U12 and U13 (the T-half test, mathematics, science). Concerning AP, the performance maxima were calculated for U12 (mathematics, science) and U11 (Arabic). Regarding PP, performance maxima were only observed for U13. Except for the moderate level, the highest levels of PA were detected in U13. Maturity status and anthropometric parameters did not differ significantly between age groups. However, AA demonstrated the most notable age-related differences. Specifically, mathematics showed substantial differences between adjacent age groups.

Differences in Physical Activity, Sedentary Behavior, Health-Related Physical Performance Indices and Academic Achievement: A Comparative Study of Normal-Weight and Obese Children in Qatar.

Background: The relationship between physical activity (PA), health-related physical performance (PP), and academic achievement (AA) plays an important role in childhood. This study examined the differences in PA, sedentary behavior, health-related PP, maturity status, and AA between normal-weight and obese school children in Qatar. Methods: Eighty schoolchildren were recruited (age: 12.1 ± 0.6 years). Based on age-specific BMI percentiles, the children were classified as normal weight (n = 40) or obese (n = 40). Moore's equations were used to estimate their maturity status (PHV). The measurements encompassed anthropometric data as well as PP tests (medicine ball throw, postural stability, handgrip strength). AA was assessed by reviewing school records for grade point average in Mathematics, Science, and Arabic courses. The total amount of time spent participating in PA each week was calculated using the International Physical Activity Questionnaire Short Form. Results: Handgrip strength was the only parameter that showed a relevant group difference (p < 0.001, ηp2 = 0.15; normal weight: 19.7 ± 3.46 N; obese: 21.7 ± 2.80 N). We found only one moderate correlation between PHV and handgrip strength (r = 0.59). Conclusions: The findings suggest that obesity status alone might not serve as a sufficient predictor of AA in school or PA levels.

Accuracy of unilateral and bilateral gait assessment using a mobile gait analysis system at different walking speeds.

BACKGROUND: Previous research on the accuracy of mobile measurement systems has focused on parameters related to the whole gait cycle. Specifically, bilateral gait characteristics were primarily used as outcome measures. RESEARCH QUESTION: How accurate are unilateral gait characteristics detected using a mobile system at various fixed walking speeds? METHODS: Gait analysis during treadmill walking at velocities (VEL) of 2.5 (v1), 4.5 (v2) and 6.5 km/h (v3) was performed in a population of 47 healthy young adults, consisting of 27 females (age: 23 ± 2 years, BMI: 21.4 ± 2.2 kg/m²) and 20 males (age: 22 ± 1 years, BMI: 23.3 ± 3.4 kg/m²). Spatiotemporal gait data were simultaneously determined using an instrumented treadmill (gaitway 3D) and a mobile gait analysis system (RehaGait). Besides VEL, bilateral (stride length [SL], cadence [CAD]) and unilateral (contact duration [CON], single [SS] and double support duration [DS]) outcomes were validated. RESULTS: Across the three VEL investigated, the correlations between both measurement systems were almost perfect in SL and CAD (r > 0.97). In addition, SL significantly differed (p < 0.01) with moderate to large effects, whereby the root mean squared error (RMSE) did not exceed 1.8 cm. RMSE in CAD was not higher than 0.33 spm and statistically significant differences were only present at v1 (d = 0.63). DS was the most erroneous unilateral parameter with values for %RMSE ranging from 9% at v1 to 14% at v3. In CON and SS %RMSE was in a magnitude of 2-4% across all VEL. Furthermore, VEL affected measurement accuracy in unilateral outcomes with moderate to large effects (F (2, 45) > 6.0, p < 0.01, ηp2 > 0.11) with consistently higher differences at lower velocities. SIGNIFICANCE: Based on the results presented the validity of the mobile gait analysis system investigated to detect gait asymmetries must be questioned.

A 10-week FIFA 11+ program improves the short-sprint and modified agility T-test performance in elite seven-a-side soccer players.

Objective: The primary objective of this study was to assess the effects of 10 weeks of FIFA 11+ training on the physical performance of elite seven-a-side soccer players. Methods: Twenty-five seven-a-side soccer players were recruited from two senior national teams. The players completed the following protocols during 10 weeks of training: a) FIFA 11+: The FIFA group (n = 13) underwent the FIFA 11+ program combined with regular soccer training; b) Dynamic conventional warm-up: The control group (n = 12) underwent regular soccer training. Their ability was validated using a pre-test followed by a post-test to measure the sprint performance (5-, 10-, and 20-m sprints), a modified agility T-test (MAT), and a five-jump test (FJT). Results: A comparison of pre- and post-tests for physical performance in each group demonstrated that the FIFA 11+ warm-up significantly improved the 10-m sprinting performance (p = 0.034; F = 5.04; ηp 2 = 0.17) and reduced the time spent to perform the MAT (p = 0.000; F = 23.16; ηp 2 = 0.52) in the FIFA group compared with the control group; however, no significant changes were observed in the 5- and 20-m sprints and FJT. Conclusion: The main findings of this research showed that the 10-week FIFA 11+ program led to significant improvements in the 10-m sprint and MAT compared to regular training among elite seven-a-side soccer players. Given these positive outcomes, further studies on the practical implementation and optimization of the FIFA 11+ program are warranted to provide valuable guidance for coaches and athletes, seeking to maximize its benefits in real-world settings.

Longitudinal Analysis of the ASES and Constant-Murley Scores, and the Internal Rotation/Shift and Jobe Tests Following Arthroscopic Repair of Supraspinatus Lesions.

It is essential to investigate patients post-surgery using functional surveys like the American Shoulder and Elbow Surgeons Shoulder (ASES) and the Constant-Murley shoulder (CMS) scores, as well as clinical tests, such as the Internal Rotation and Shift (IRO/Shift) and Jobe tests. In this study, 51 out of an initial 87 patients underwent an arthroscopic supraspinatus repair (22 single-row, 16 double-row, 13 debridement). Testing occurred pre-surgery, and 3 and 6 months post-surgery. Both surveys showed significant improvements over time among all 87 patients, but there were no differences between groups (lesion/no lesion) (p > 0.815) or time × group (p > 0.895). The IRO/Shift test showed a stronger ability to distinguish between both groups (positive vs. negative) with respect to the ASES and CMS scores over time, but the Jobe test did not (p > 0.100). Improvements in the CMS scores and the Jobe test were lower following repair compared to the ASES and IRO/Shift test. Most patients returned to adequate levels of functional abilities at 6 months post-surgery. The time required to return to activities of daily living and negative clinical tests was longer for the double-row repair patients compared to the single-row and debridement groups. In conclusion, both the functional surveys and the clinical tests demonstrated improvements following surgery.

Effects of Sensorimotor Training on Transversus Abdominis Activation in Chronic Low Back Pain Patients.

(1) Background: The aim of this study was to investigate and compare the effect of sensorimotor training on transversus abdominis activation. (2) Methods: Seventy-five patients with chronic low back pain were randomly assigned to one of three groups (whole body vibration training using Galileo®, coordination training using Posturomed®, or physiotherapy (control)). Transversus abdominis activation was measured by using sonography pre- and post-intervention. Second, changes in clinical function tests and their correlation with the sonographic measurements were determined. (3) Results: All three groups showed an improvement in activation of the transversus abdominis post-intervention, with the Galileo® demonstrating the largest improvement. There were no relevant (r > 0.5) correlations between activation of the transversus abdominis muscle and any clinical tests. (4) Conclusions: The present study provides evidence that sensorimotor training on the Galileo® significantly improves the activation of the transversus abdominis muscle.

Differences in body composition, static balance, field test performance, and academic achievement in 10-12-year-old soccer players.

Introduction: This study aimed to compare 10-12-year-old Qatari male soccer players (n = 45) regarding different dimensions (anthropometric, academic and physical performance). Methods: Anthropometric parameters (body mass, fat percentage (%BF), body mass index (BMI)) academic achievement (mathematics and science grade point average [GPA]) and physical performance [Yo-Yo Intermittent Recovery Test (level 1), squat jumps (SJ), counter-movement jumps (CMJ), stork balance test, 10 and 15 m sprint tests, T-half test for change-of-direction (CoD) ability, hand-grip strength, medicine ball throw (MBT)] were measured. Schoolchild soccer players were divided into three groups: 12-year-old players (U12; n = 16), 11-year-old players (U11; n = 14), 10-year-old players (U10; n = 15). Results: Apart from mathematics, Yo-Yo IR1 and 10 m sprint, all performance parameters showed significant age effects. The largest age-related difference was observed for 15 m sprint (p < 0.001). Both adjacent age groups displayed significant differences for 15 sprint (U10 vs. U11: p = 0.015; U11 vs. U12: p = 0.023). Concerning academic performance, a significant age effect was found for science (p < 0.001). There was a main age effect on academic performance difference between U10 and U11 (p = 0.007). Academic parameters did not correlate with any physical performance parameter or anthropometric parameter. The strongest correlations were detected for body height and agility T-half test (r = -0.686) and medicine ball throw (r = 0.637). The biological maturity was strongly correlated with handgrip strength (r = -0.635). Discussion: Soccer coaches and physical education teachers can use these data as reference values for evaluation of school-aged soccer players, and for ascertaining specific training targets. Obviously, short sprinting ability and aerobic capacity are not functions of age and need a specific training for significant improvements.

Effects of Different Forms of Sensorimotor Training on Postural Control and Functional Status in Patients with Chronic Low Back Pain.

The aim of this study was to compare three sensorimotor training forms in patients with chronic low back pain to determine their effects on the reduction of pain-related impairment and changes in posturography. Over two weeks, during the multimodal pain therapy (MMPT) period, six sessions of sensorimotor physiotherapy or training in the Galileo® or Posturomed® (n = 25 per group) were performed. A significant reduction in pain-related impairment after the intervention phase was shown across all groups (time effect: p < 0.001; ηp2 = 0.415). There was no change in postural stability (time effect: p = 0.666; ηp2 = 0.003), but there was a significant improvement in the peripheral vestibular system (time effect: p = 0.014; ηp2 = 0.081). An interaction effect was calculated for the forefoot-hindfoot ratio (p = 0.014; ηp2 = 0.111). Only the Posturomed® group showed an improvement in anterior-posterior weight distribution (heel load: 47% vs. 49%). These findings suggest that these forms of sensorimotor training in the context of MMPT are suitable for reducing pain-related impairment. Posturography demonstrated stimulation of a subsystem, but no improvement in postural stability.

A Longitudinal Analysis of the Internal Rotation and Shift (IRO/Shift) Test Following Arthroscopic Repair of Superior Rotator Cuff Lesions.

Although the use of clinical tests to diagnose superior rotator cuff pathology is common, there is paucity in the research regarding the accuracy of such tests following arthroscopic repair. The aim of this study was to determine the accuracy of the IRO/Shift test compared to the Jobe test at 3 months and 6 months post-surgery for superior rotator cuff repair. Arthroscopic repair was conducted on 51 patients who were subsequently seen for clinical evaluation at 3 and 6 months following surgery. At 3 months post-surgery only 27% of the patients had a negative IRO/Shift test and 18% had a negative Jobe test. However, at 6 months 88% of the patients presented with a negative IRO/Shift test and 61% a negative Jobe test. When compared to each other, the IRO/Shift test and the Jobe test had 90% agreement pre-operatively, 71% agreement at 3 months post-surgery, and 67% agreement at 6 months. These results demonstrate that the accuracy of the IRO/Shift test and the Jobe test improved between 3 and 6 months following arthroscopic surgery of the superior rotator cuff, with the IRO/Shift test having better accuracy.

Standing Steadiness and Asymmetry after High Tibial Osteotomy Surgery: A 2 Year Follow-Up Study.

(1) Background: Knee osteoarthritis (OA) is a serious orthopedic problem. In this context, the high tibial osteotomy (HTO) is an established surgical procedure to reduce the load and degeneration of the affected compartment. The aim of this investigation was to judge standing steadiness and asymmetry, pain intensity and quality of life among patients who underwent HTO surgery. (2) Methods: Twenty-five male patients with medial tibiofemoral OA finished this 2 year follow-up study. Standing balance was captured using force plates with four uniaxial sensors before, 6 weeks after, 1 year after, and 2 years after HTO surgery. The percentage weight (PW) under the foot at one side, the stability (ST) index and the weight distribution (WD) index were the main outcomes. Comparisons were conducted using repeated measures analyses of variance. (3) Results: Over time, the PW under the foot at the HTO side increased on average (p < 0.001). In terms of standing steadiness, the average ST remained similar over the time points (p = 0.71). The WD index was affected by time (p = 0.003). (4) Conclusions: In order to judge short-term effects, the PW is recommended, whereas long-term effects can be identified either through the PW or the WD index.

IRO/Shift Test Is Comparable to the Jobe Test for Detection of Supraspinatus Lesions.

To determine how the internal rotation and shift (IRO/shift) test compares to the gold standard of clinical tests (Jobe test) for diagnosing supraspinatus lesions and to confirm these clinical results with surgical findings, 100 symptomatic patients were clinically examined between October 2018 and November 2019. All 100 patients were evaluated using both the IRO/shift test and Jobe test. A total of 48 of these patients received surgical intervention. Based on these data, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for both the IRO/shift test and Jobe test were calculated. The IRO/shift test had a sensitivity of 96% (95% CI: 82-100%), specificity of 50% (95% CI: 27-73%), PPV of 73% (95% CI: 56-86%), NPV of 91% (95% CI: 59-100%), and an accuracy of 77% (95% CI: 63-88%). The Jobe test had a sensitivity of 89% (95% CI: 72-98%), specificity of 60% (95% CI: 36-81%), PPV of 76% (95% CI: 58-89%), NPV of 80% (95% CI: 52-96%), and an accuracy of 77% (95% CI: 54-81%). These results suggest that the IRO/shift test is comparable to the Jobe test, which is often viewed as the gold standard clinical examination for assessing supraspinatus lesions. This study was approved by the Ethics Commission of the Martin Luther University Halle-Wittenberg (reference number: 2018-05).

Influence of Hearing Rehabilitation With Active Middle Ear and Bone Conduction Implants on Postural Control.

Background: As audition also seems to contribute to balance control, additionally to visual, proprioceptive, and vestibular information, we hypothesize that hearing rehabilitation with active middle ear and bone conduction implants can influence postural control. Methods: In a prospective explorative study, the impact of hearing rehabilitation with active middle ear [Vibrant Soundbrige (VSB), MED-EL, Innsbruck, Austria] and bone conduction implants [Bonebridge (BB), MED-EL, Innsbruck, Austria] on postural control in adults was examined in three experiments. Vestibulospinal control was measured by cranio-corpography (CCG), trunk sway velocity (°/s) by the Standard Balance Deficit Test (SBDT), and postural stability with a force plate system, each time in best aided (BA) and unaided (UA) condition with frontal-noise presentation (Fastl noise, 65 dB SPL), followed by subjective evaluation, respectively. Results: In 26 subjects [age 55.0 ± 12.8 years; unilateral VSB/BB: n = 15; bilateral VSB/BB: n = 3, bimodal (VSB/BB + hearing aid): n = 8], CCG-analysis showed no difference between BA and UA conditions for the means of distance, angle of displacement, and angle of rotation, respectively. Trunk sway measurements revealed a relevant increase of sway in standing on foam (p = 0.01, r = 0.51) and a relevant sway reduction in walking (p = 0.026, r = 0.44, roll plane) in BA condition. Selective postural subsystem analysis revealed a relevant increase of the vestibular component in BA condition (p = 0.017, r = 0.47). As measured with the Interactive Balance System (IBS), 42% of the subjects improved stability (ST) in BA condition, 31% showed no difference, and 27% deteriorated, while no difference was seen in comparison of means. Subjectively, 4-7% of participants felt that noise improved their balance, 73-85% felt no difference, and 7-23% reported deterioration by noise. Furthermore, 46-50% reported a better task performance in BA condition; 35-46% felt no difference and 4-15% found the UA situation more helpful. Conclusions: Subjectively, approximately half of the participants reported a benefit in task performance in BA condition. Objectively, this could only be shown in one mobile SBDT-task. Subsystem analysis of trunk sway provided insights in multisensory reweighting mechanisms.

The internal rotation and shift-test for the detection of superior lesions of the rotator cuff: reliability and clinical performance.

Background: Using reliable and valid clinical tests are essential for proper diagnosis and clinical outcomes among injuries involving the rotator cuff. The addition of a new clinical examination test could improve the clinical diagnosis and informative value of the sensitivity and specificity of pathology. This study of diagnostic accuracy evaluated the use of a new rotator cuff test, called the internal rotation and shift-test (IRO/shift-test), to determine its reliability and clinical performance (sensitivity, specificity, positive (PPV)/negative predictive value (NPV)). Clinical diagnostic outcomes were confirmed with radiological findings (MRI). Methods: 100 patients from a specialized shoulder unit participated (64 male, 36 female, mean age: 55 ± 13.5 years). A single-blinded (no knowledge of prior clinical or technical diagnostics) study design was used with two experienced physicians performing the IRO/shift-test. For clinical performance, all clinical testing was compared with MRI. Results: The intra-rater (ICC = 0.73, 95% CI: 60-82) and inter-rater (ICC = 0.89, 95% CI: 81-94) coefficients for the IRO/shift-test showed good-to-excellent reliability. 75% of the patients showed a positive IRO/shift-test, while 65% had a radiologically diagnosed superior rotator cuff tear. 60% of these patients had both a positive IRO/shift-test and objective rotator cuff tear via MRI. The sensitivity of the IRO/shift-test to detect superior rotator cuff lesions based on MRI diagnosis was calculated at 92% (95% CI: 86-99%), while specificity was 67% (95% CI: 50-84%). Predictive values were also found to be high with 86% PPV (95% CI: 78-94%) and 80% NPV (95% CI: 64-96%). Conclusion: Our results demonstrate that the IRO/shift-test is a reliable and valid tool for assessing superior rotator cuff pathology. With good-to-excellent intrarater and inter-rater reliability and strong sensitivity and specificity this test should be considered a valuable addition to clinicians' cadre of clinical evaluation tools.

Differences in Health-Related Physical Fitness and Academic School Performance in Male Middle-School Students in Qatar: A Preliminary Study.

This study examined the differences in the level of physical fitness and academic performance among male middle-school children based on different body status categories. A total of 69 male children [age: 12.4 ± 0.7 years; body mass: 58.5 ± 7.2 kg; height: 1.62 ± 0.09 m; and body mass index (BMI): 22.4 ± 3.3 kg/m2] participated and were divided into BMI age-adjusted groups (i.e., lowest, middle, and highest BMI). Height, mass, BMI, stork test of static balance, 10 and 15 m sprint as an indicator for speed, hand-grip strength test, agility T-half test, medicine ball throw (MBT), and the Yo-Yo Intermittent Recovery Test level 1 (Yo-Yo IR1) were assessed. School records were retrieved for grade point averages (GPA) of mathematics, science, and Arabic. We found significant group differences regarding anthropometric (height: η p 2 = 0.24, mass: η p 2 = 0.33, and BMI: η p 2 = 0.66), physical (sprint 10 m: η p 2 = 0.26), and academic (mathematics: η p 2 = 0.19 and science: η p 2 = 0.15) performance parameters. The largest difference (p < 0.001) was observed between the lowest and highest group for the 10 m sprint. All pairwise differences were between the lowest and highest BMI group or the lowest and middle BMI group. No relevant (r > 0.5) correlation between parameters of different dimensions (e.g., anthropometric vs. physical performance parameters) was found. In conclusion, the highest BMI group exhibited similar physical and academic performances than the lowest group. Thus, these data emphasize the importance and appropriateness to engage young Qatari schoolchildren in physical activity as it associates with superior academic performance.

Fitness, Fatness, and Academic Attainment in Male Schoolchildren from a Soccer Academy.

This investigation explored the association between anthropometric measures, fitness, and academic attainment (mathematics and science grade point average [GPA]) in male schoolchildren from a soccer academy. Thirty-one males (age: 10.3 ± 1.19 years; body mass: 41.7 ± 6.5 kg; height: 1.43 ± 0.07 m; body mass index (BMI): 20.2 ± 2.8 kg/m2) participated. Body mass, body fat percentage (%BF), and BMI were used as measures of anthropometry. The Yo-Yo Intermittent Recovery Test (level 1), squat and counter-movement jumps (SJ and CMJ), static balance, 10 and 15 m sprint, and a T-half test for change-of-direction (CoD) performance were used to measure fitness parameters. The GPA of mathematics and science determined academic attainment. All physical performance tests showed excellent relative reliability. ICC was between 0.87 (10 m sprint) and 1.00 (15 m sprint, CMJ). Regarding correlations between fatness and academic attainment, we found three correlations of practical value (r > 0.5), but only for mathematics (BMI: r = 0.540, subscapular skinfold: r = 0.589, body fat: r = 0.560). Mathematics was relevantly correlated with 15 m sprint (r = 0.574) and Yo-Yo IR1 test (r = 0.770). Only static balance (r = 0.428) did not reach the relevance criteria (r > 0.5). Science only showed large correlations with static balance (r = 0.620) and Yo-Yo IR1 test (r = 0.730). In conclusion, fatness and fitness are related to academic attainment in schoolchildren. In addition, except for static balance, all physical performance parameters were relevantly (r > 0.5) correlated with mathematics.

Combined Plyometric and Short Sprint Training in U-15 Male Soccer Players: Effects on Measures of Jump, Speed, Change of Direction, Repeated Sprint, and Balance.

This study examined the effect of 8 weeks of biweekly combined plyometric and short sprint training into the typical within-season training schedule of youth male soccer players. Participants were allocated at random to an experimental group (EG; n = 17, age: 14.6 ± 0.5 years, body mass: 60.5 ± 7.1 kg, height: 1.64 ± 0.08 m, body fat: 11.3 ± 1.4%) and a control group (CG; n = 17, age: 14.6 ± 0.4 years, body mass: 61.0 ± 3.9 kg, height: 1.67 ± 0.05 m, body fat: 11.8 ± 1.4%). Measures obtained pre- and post-intervention included vertical and horizontal jump performances (i.e., squat jump (SJ), countermovement jump with aimed arms (CMJA), and five-jump test (FJT)) and sprint performances (i.e., 10 and 30 m sprint). In addition, change-of-direction ability (sprint with 90° Turns (S90°) and sprint 9-3-6-3-9 m with backward and forward running (SBF)), repeated shuttle sprint ability (RSSA), and dynamic balance performance (Y balance test) were measured pre- and post-intervention. The EG experienced higher jump (all p < 0.05; d ≥ 0.71), sprint (all p < 0.05; d ≥ 0.64), change-of-direction ability (all p < 0.05; d ≥ 0.66), RSSA (all parameters except the fatigue index p < 0.01; d ≥ 0.71), and dynamic balance (all p ≤ 0.05; d ≥ 0.50) improvement compared to the CG. Adding biweekly combined plyometric and short sprint training to standard training improves the athletic performance of youth male soccer players (under 15 (U15)).

Foot tapping and unilateral vertical jump performance in athletes after knee surgery: an explorative cross-sectional study.

BACKGROUND: Guiding athletes through the rehabilitation process and judging the time at which return to sports can be enabled after anterior cruciate ligament (ACL) injuries are still challenging processes. The purpose of this explorative cross-sectional study was to retrospectively compare unilateral vertical jump as well as vertical foot tapping outcomes in athletes returned to sports after ACL reconstruction (ACLR) with uninjured athletes. METHODS: Seven-teen ACLR athletes (male/female: 12/5) were examined 11 (6-23) months after their ACL injury and after return to sport clearance together with 67 uninjured athletes (male/female: 51/16). Seventeen age and stature matched controls were selected from the sample of uninjured athletes. Participants unilaterally performed acyclic (squat jump, SJ; drop jump, DJ) and cyclic (foot tapping, FT) tests. SJ peak power, DJ take-off efficiency (TOE) and FT coefficients (FTC) were compared between ACLR and matched as well as unmatched control groups. Limb symmetry index (LSI) as well as performance score were calculated. RESULTS: Analyses of the SJ peak power revealed moderate effects of group (right: P < 0.09, ηp2 = 0.06; left: P < 0.05, ηp2 = 0.08). The TOE was largely affected by group (right: P < 0.01, ηp2 = 0.12; left: P < 0.01, ηp2 = 0.13). No effect of group was found on the FTC (P > 0.8, ηp2 < 0.01). The SJ peak power LSI (r = 0.46, P < 0.07) and TOE LSI (r = 0.38, P = 0.13) were positively associated with the performance score of the ACLR group. CONCLUSION: Although already returned to sports, the ACLR group underperformed the matched and unmatched control groups significantly. Unilaterally performed vertical jumps may provide additional information on athletes' rehabilitation progress and help to manage the rehabilitation process and decisions on potential readiness after ACLR. More attention should be paid to the direction of the LSI results.

An 8-Week Program of Plyometrics and Sprints with Changes of Direction Improved Anaerobic Fitness in Young Male Soccer Players.

This study examined the effects of 8 weeks of twice-weekly combined plyometric and sprint with change-of-direction (CPSCoD) training into habitual training regimes of young male soccer players. Participants were randomly allocated to an experimental group (n = 17, age: 14.6 ± 0.44 years, body mass: 61.2 ± 7.34 kg, height: 1.67 ± 0.09 m, body fat: 11.2 ± 1.56%) and a control group (n = 16, age: 14.6 ± 0.39 years, body mass: 61.1 ± 3.96 kg, height: 1.67 ± 0.05 m, body fat: 11.8 ± 1.47%). Measures obtained pre- and post intervention included vertical and horizontal jump performance (i.e., squat jump (SJ), countermovement jump (CMJ), and standing long jump (SLJ)), and sprint performance (i.e., 5 m and 20 m sprint). In addition, Measures obtained pre- and post-intervention included change-of-direction ability (4 × 5 m sprint test (S 4 × 5 m) and sprint 9-3-6-3-9 m with backward and forward running (SBF)), repeated change of direction (RCoD), and static balance performance (stork balance test). The training group experienced superior jump (all p < 0.05; d ≥ 0.61), sprint (all p < 0.05; d ≥ 0.58), change-of-direction (CoD) ability (all p < 0.05; d ≥ 0.58), RCoD (all parameters except the fatigue index p < 0.01; effect size (d) ≥ 0.71), and static balance (all p < 0.05; d ≥ 0.66) improvement. Adding twice-weekly CPSCoD training to standard training improves the anaerobic performance of U15 male soccer players.