Specific Game-Based Performance in Elite Male Adolescent Team Handball Players.

PURPOSE: In elite team handball, talent identification and selection of the best young players is a fundamental process in several national federations and clubs; however, literature addressing the specific game-based performance in team handball is almost nonexistent. Consequently, the aim of the study was to assess and compare the team-handball-specific game-based performance of elite male team handball players of different ages. METHODS: Twelve under-23, 10 under-19, 10 under-17, and 10 under-15 elite male players performed the team-handball game-based performance test. During testing, oxygen uptake, heart rate, sprinting time in defense, offense, fast breaks, and fast retreats, as well as ball velocity and jump height in the jump shot, were measured. RESULTS: Significant differences (P < .05) between under-23, under-19, under-17, and under-15 players were found for absolute peak oxygen uptake, defense, offense and fast break time, ball velocity, and jump height in the game-based performance test, as well as in body weight and height. CONCLUSION: The results revealed that with increasing age, elite male team handball players are heavier and taller (body weight and height); faster (team-handball offense, defense, and fast break); jump higher and throw faster (in the team-handball jump shot); and perform better aerobically (absolute peak oxygen uptake). The better performance in the under-23 and under-19 players compared with male adult players competing in a lower National Federation league (not on top-elite level) demonstrates that highly specific game-based physical performance determines the potential for developing young male team handball players for competition at the top level.

Assessment of the Maximal Range of Motion from Initial Sensation of Stretching to the Limits of Tolerance.

The aim of this study was to determine whether the first sensation of stretching (ROMFSS) may predict the maximum range of motion (ROMMAX) in male (N = 37) and female (N = 32) volunteer subjects, and to assess the reliability of the ROM perceived by subjects in relation to a pre-determined ROM (ROM50%). Subjects attempted three experimental sessions with 48 hours between sessions 1 and 2 and 28 days between sessions 1 and 3. Within each session, five trials were performed with isokinetic equipment to assess posterior thigh muscle flexibility. The results revealed a strong and significant correlation between ROMMAX and ROMFSS for both sexes, females (r = 0.96, p < 0.001, R2 = 0.92) and males (r = 0.91, p < 0.001; R2 = 0.82). The accuracy of the model verified by the standard error of estimate (SEE) was high in the equations proposed for both female (SEE = 4.53%) and male (SEE = 5.45%). Our results revealed that ROMFSS may predict the ROMMAX for both male and female subjects. The ROMFSS may contribute to the development of evaluation methods that do not subject the individuals to conditions that may include unnecessary risk of injury and is well suited to monitor the training process of stretching exercises with submaximal loads.

Testing-Specific Skating Performance in Ice Hockey.

ABSTRACT: Hajek, F, Keller, M, Taube, W, von Duvillard, SP, Bell, JW, and Wagner, H. Testing-specific skating performance in ice hockey. J Strength Cond Res 35(12S): S70-S75, 2020-Skating performance generally determines overall performance in ice hockey but has not been measured adequately in the past. Consequently, the aim of the study was to develop and validate a specific overall skating performance test for ice hockey (SOSPT) that includes similar movements and intensities as in competition. Ten male elite under-14-year and under-18-year old ice hockey players performed the SOSPT (2 heats only) and a 40-m on-ice sprinting test twice within 8 days. Additionally, 14 under-15, 18 under-17, and 20 under-20 male elite ice hockey players performed only the SOSPT (4 heats). Time was measured from the first subject's movement during a V-start until crossing the line (40-m on-ice sprinting test), first touch of the shoulder on the mat (heat #1 in the SOSPT) or first touch of the puck with the stick (heat #2 in the SOSPT) using a hand stopwatch. We found a high test-retest reliability of the SOSPT and 40-m on-ice sprinting test (interclass correlation coefficient, >0.7; coefficient of variation, <5%) with highly significant differences (p < 0.001) between the under-15, under-17, and under-20 players, a high correlation (r > 0.70) between an expert rating and the SOSPT, and a low correlation between the 40-m on-ice sprinting test and the SOSPT in the under-14 and under-18 players. The results of the study reveal that the SOSPT is a reliable and valid test to determine the specific overall skating performance in ice hockey players and is more suitable compared with straight skating tests of the 40-m on-ice sprinting test.

Effect of Differential Training on Female Volleyball Spike-Jump Technique and Performance.

PURPOSE: To determine the effect of in-season differential training on volleyball spike-jump technique and performance in elite-level female players. METHODS: During the season, spike jumps of 12 elite female players (Austrian Volleyball League Women) were recorded by 13 Qualisys Oqus cameras (250 Hz) and an AMTI force plate (1000 Hz). First measurement was made at the beginning of the investigation. Two identical measurements were repeated after a first and a second interval. The first interval served as control phase. The second interval was comparable in length and regular program but included differential training (6 wk, 8 sessions of 15-20 min) as a modified warm-up. It addressed specific performance determinants. Analyses of variances were calculated for the 3 measurements and for the development during control and intervention phase. RESULTS: Initial jump height (0.44 [0.09] m) changed by -4.5% during the control phase and +11.9% during the intervention (P < .001, ηp2=.70). All approach variables, arm backswing, and velocity-conversion strategy improved compared with the control phase (Δ%: 6.1-51.2%, P < .05, ηp2=.40-.80). Joint angles, countermovement depth, maximal angular velocities, and torso incline were not affected (Δ%: -2.9-9.1%, P = .066-.969, ηp2=.00-.27). CONCLUSIONS: In-season differential training led to technical adaptations and increased spike-jump height in elite female players. The differential training program allowed players to experience a range of adaptability and to adjust toward an individual optimum in technical components of performance determinants. Coaches are encouraged to apply technical differential training to elite athletes and to target biomechanical performance factors specifically.

Testing Specific Physical Performance in Male Team Handball Players and the Relationship to General Tests in Team Sports.

Wagner, H, Sperl, B, Bell, JW, and von Duvillard, SP. Testing specific physical performance in male team handball players and the relationship to general tests in team sports. J Strength Cond Res 33(4): 1056-1064, 2019-Team handball is exemplified by frequent changes in intensities and different complex movements during games, whereas physical performance has often been tested predominantly using standardized general tests. The study aimed (a) to determine the relationship between specific and general physical performance as well as between specific aerobic capacity and agility, and (b) to ascertain the relevance of these tests for strength and conditioning professionals. Seventy-two male indoor court players performed a game-based performance test (GBPT) including team handball-specific techniques, upper-body and lower-body strength tests, a 30-m sprint test, a countermovement jump Abalakov (CMJA) test (with arm swing), and an incremental treadmill-running test. To assess the specific physical performance using the general test performance, we used linear regression calculations. In addition, a principal component factor analysis was calculated. Linear regression analyses revealed a low correlation (R < 0.5) between specific and general aerobic performance, 30-m sprinting time and specific agility in the GBPT, jump height in the CMJA test and jump height in the jump shot, as well as isokinetic shoulder rotation torque and ball velocity in the jump shot. However, a moderate correlation (R > 0.5) was found between specific aerobic performance and specific agility in the GBPT. Principal component factor analysis yielded separate components for specific and general physical performance with a cumulative variance of 69%. The results of this study clearly indicated that general and team handball-specific performance are separate components. Recommendations to strength and conditioning professionals and coaches in team handball were presented.

Movement characteristics of volleyball spike jump performance in females.

OBJECTIVES: Performance factors in the volleyball spike jump are well known for male players; however, technical-coordinative differences for female players are known only marginally. The objective of this study was to investigate the relationship between movement characteristics and female' spike jump performance and to identify the most relevant aspects of jump height and ball velocity. DESIGN: Single group correlation and regression. METHODS: Fifteen elite female volleyball players performed spike jumps by striking a stationary ball at maximal jump height. Data were collected via twelve MX13 Vicon cameras (250Hz), two AMTI force plates (2000Hz), and controlled via Visual3D software. RESULTS: Ten out of 42 characteristics correlated with jump height and none of 22 correlated with ball velocity. A stepwise regression model (adjusted R2=0.82, p<0.001) predicted jump height based on orientation step length and maximal angular velocity of dominant knee extension. For ball velocity, stepwise regression analysis was not feasible; however, an alternative model yielded adjusted R2=0.55, p<0.01. CONCLUSIONS: Key aspects for jump height were (1) optimised approach and energy conversion, (2) wide dynamic arm swing allowing for a forceful countermovement and, thus, increased range of motion in lower limbs, and (3) large angular velocities in ankles and knees, especially on the dominant side. These aspects strongly determined jump height in females and should be included in technical and strength-related training. For ball velocity, upper body anthropometrics and angular joint velocities emerged as the most important criteria. The importance of specific joints may depend on variations in striking technique.

Physical Performance in Elite Male and Female Team-Handball Players.

PURPOSE: Biological differences between men and women are well known; however, literature addressing knowledge about the influence of sex on specific and general performance in team handball is almost nonexistent. Consequently, the aim of the study was to assess and compare specific and general physical performance in male and female elite team-handball players, to determine if the differences are consequential for general compared with specific physical performance characteristics and the relationship between general and specific physical performance. METHODS: Twelve male and 10 female elite team-handball players performed a game-based performance test, upper- and lower-body strength and power tests, a sprinting test, and an incremental treadmill running test. RESULTS: Significant differences (P < .05) between male and female players were found for peak oxygen uptake and total running time during the treadmill test, 30-m sprinting time, leg-extension strength, trunk- and shoulder-rotation torque, and countermovement-jump height, as well as offense and defense time, ball velocity, and jump height in the game-based performance test. An interaction (sex × test) was found for time and oxygen uptake, and except shoulder-rotation torque and ball velocity in women, the authors found only a low relationship between specific and general physical performance. CONCLUSION: The results of the study revealed that male players are heavier, taller, faster, and stronger; jump higher; and have better aerobic performance. However, female players performed relatively better in the team-handball-specific tests than in the general tests. The findings also suggest that female players should focus more on strength training.

Effects of Dual-Task Management and Resistance Training on Gait Performance in Older Individuals: A Randomized Controlled Trial.

Background: Dual-task (DT) training is a well-accepted modality for fall prevention in older adults. DT training should include task-managing strategies such as task switching or task prioritization to improve gait performance under DT conditions. Methods: We conducted a randomized controlled trial to evaluate a balance and task managing training (BDT group) in gait performance compared to a single task (ST) strength and resistance training and a control group, which received no training. A total of 78 older individuals (72.0 ± 4.9 years) participated in this study. The DT group performed task managing training incorporating balance and coordination tasks while the ST group performed resistance training only. Training consisted of 12 weekly sessions, 60 min each, for 12 weeks. We assessed the effects of ST and BDT training on walking performance under ST and DT conditions in independent living elderly adults. ST and DT walking (visual verbal Stroop task) were measured utilizing a treadmill at self-selected walking speed (mean for all groups: 4.4 ± 1 km h-1). Specific gait variables, cognitive performance, and fear of falling were compared between all groups. >Results: Training improved gait performance for step length (p < 0.001) and gait-line (ST: p < 0.01; DT p < 0.05) in both training groups. The BDT training group showed greater improvements in step length (p < 0.001) and gait-line (p < 0.01) during DT walking but did not have changes in cognitive performance. Both interventions reduced fear of falling (p < 0.05). Conclusion: Implementation of task management strategies into balance and strength training in our population revealed a promising modality to prevent falls in older individuals. Trial registration: German register of clinical trials DRKS00012382.

Altered resting hemodynamics in lower-extremity arteries of individuals with spinal cord injury.

OBJECTIVE: To investigate lower-extremity arterial hemodynamics in individuals with spinal cord injury (SCI). We hypothesized that oscillatory shear index would be altered and resting mean shear would be higher in the lower-extremity arteries of SCI. RESEARCH: Cross-sectional study of men and women with SCIs compared to able-bodied controls. SUBJECTS: Subjects included 105 ages 18-72 years with American Spinal Injury Association (ASIA) Impairment Scale grades A, B, or C and injury duration at least 5 years. Subjects were matched for age and cardiovascular disease risk factors with 156 able-bodied controls. METHODS: Diameter and blood velocity were determined with subject at rest via ultrasound in superficial femoral, popliteal, brachial, and carotid arteries. Mean shear, antegrade shear, retrograde shear, and oscillatory shear index were calculated. RESULTS: Oscillatory shear index was lower in SCI compared to controls for superficial femoral (0.16 ± 0.10 vs. 0.26 ± 0.06, P < 0.01) and popliteal arteries (0.20 ± 0.11 vs. 0.26 ± 0.05, P < 0.01). Mean shear rate was higher in SCI compared to controls for superficial femoral (43.54 ± 28.0 vs. 20.48 ± 13.1/second, P < 0.01) and popliteal arteries (30.43 ± 28.1 vs. 11.68 ± 9.5/second, P < 0.01). CONCLUSIONS: The altered resting hemodynamics in SCI are consistent with an atheroprotective hemodynamic environment.

Evidence for greater burden of peripheral arterial disease in lower extremity arteries of spinal cord-injured individuals.

Spinal cord injury leads to increased risk for cardiovascular disease and results in greater risk of death. Subclinical markers of atherosclerosis have been reported in carotid arteries of spinal cord-injured individuals (SCI), but the development of lower extremity peripheral arterial disease (PAD) has not been investigated in this population. The purpose of this study was to determine the effect of spinal cord injury on ankle-brachial index (ABI) and intima-media thickness (IMT) of upper-body and lower-extremity arteries. We hypothesized that the aforementioned measures of lower-extremity PAD would be worsened in SCI compared with controls and that regular participation in endurance exercise would improve these in both groups. To test these hypotheses, ABI and IMT were determined in 105 SCI and compared with 156 able-bodied controls with groups further subdivided into physically active and sedentary. ABIs were significantly lower in SCI versus controls (0.96 ± 0.12 vs. 1.06 ± 0.07, P < 0.001), indicating a greater burden of lower-extremity PAD. Upper-body IMTs were similar for brachial and carotid arteries in controls versus SCI. Lower extremity IMTs revealed similar thicknesses for both superficial femoral and popliteal arteries, but when normalized for artery diameter, individuals with SCI had greater IMT than controls in the superficial femoral (0.094 ± 0.03 vs. 0.073 ± 0.02 mm/mm lumen diameter, P < 0.01) and popliteal (0.117 ± 0.04 vs. 0.091 ± 0.02 mm/mm lumen diameter, P < 0.01) arteries. The ABI and normalized IMT of SCI compared with controls indicate that subclinical measures of lower-extremity PAD are worsened in individuals with SCI. These findings should prompt physicians to consider using the ABI as a screening method to detect lower-extremity PAD in SCI.

Impact of chronic intermittent external compressions on forearm blood flow capacity in humans.

During dynamic exercise, the vasculature embedded within skeletal muscle intermittently collapses due to increased intramuscular pressure (IMP). The aim of this study was to ascertain whether oscillations in IMP during muscle contractions independently contribute to exercise training-induced increases in blood flow capacity (BFC). Based on IMP measurements during handgrip exercise, we attempted to mimic the action of repeated vascular compressions by using external inflatable cuffs. Thus, 24 healthy young male subjects underwent a 4-week program (5 days/week, 1 h/day) of application of external compressions of the non-dominant forearm, while the dominant limb served as an internal control. To evaluate the impact of compression pressures of different magnitudes, subjects were randomly assigned to one of three groups: 50, 100 and 150 mmHg of external compression. Prior to the intervention and after 2 and 4 weeks of treatment, we measured peak forearm blood flow (PBF) (Doppler ultrasound) and calculated peak vascular conductance (PVC) following 10 min of forearm ischemia. In the 50 and 100 mmHg groups, application of intermittent compressions did not alter PBF in either control or intervention forearms. In the 150 mmHg group, there was a trend (P = 0.04) for greater increases in PBF from baseline after 4 weeks in the intervention forearm compared to the control forearm (delta PBF: 4.2 ± 2.5 vs. -2.1 ± 2.0 (ml(100 ml)(-1) min(-1)), in the intervention and control forearms, respectively), but the changes in PVC were not significant (P = 0.1). These findings suggest that repeated oscillations in IMP contribute minimally to exercise-induced increase in forearm BFC in healthy young humans.

Comparison of Body Composition Measurements Using a New Caliper, Two Established Calipers, Hydrostatic Weighing, and BodPod.

PURPOSES: (1) To compare the Lafayette Instruments (LI) skinfold caliper to the Lange (L) and Harpenden (H) calipers using a diverse subject population. (2) To determine the validity of the LI caliper in a subset of subjects by comparing body compositions from skinfold thicknesses to those measured by hydrostatic weighing (HW) and air displacement plethysmography (ADP). (3) To compare measurements obtained by experienced (EX) and inexperienced (IX) technicians using all three calipers. METHODS: Skinfold measurements were performed by both EX and IX technicians using three different calipers on 21 younger (21.2 ± 1.5 yrs) and 20 older (59.2 ± 4 yrs) subjects. Body compositions were calculated using the Jackson-Pollock seven-site and three-site formulas. HW and ADP tests were performed on a subset of subjects (10 younger, 10 older). RESULTS: No significant differences existed between LI and L or H when measurements were made by EX. Further, the LI-EX measurements were highly correlated to both H-EX and L-EX. No significant differences existed in the subgroup between LI-EX and HW or ADP. Skinfold determinations made by EX and IX were similar. CONCLUSIONS: Similar body compositions determined using LI, H, and L suggest that LI determines body composition as effectively as H and L. High correlations between the three calipers support this notion. Similar results between LI and HW/ADP subgroup suggest that the LI caliper may be a valid method of measuring body composition. Overall, performance by IX was similar to EX and suggests similar ease of use for all three calipers.