Handball Players Research Articles

The Effect of Fluid Restriction and Intake Conditions on the Shooting Performance of Competitive Adolescent Handball Players

(1) Background: This study aimed to investigate the effects of fluid restriction and intake (water vs. sports drink) on shooting accuracy and speed in adolescent handball players, a population with high sensitivity to hydration levels yet understudied in this context. (2) Methods: A total of 47 adolescent competitive handball players (15.04 ± 1.5 years) were included in this study, and the participants were divided into low, average, and high performance according to their shooting performance in the familiarization session. All participants were exposed to fluid restriction and intake conditions during handball training on different days. Before and after the training sessions, changes in shooting accuracy and speed were evaluated. (3) Results: The training protocol resulted in body mass loss in the Average Performer group (p = 0.001). Compared to fluid restriction, fluid intake (water intake and sports drink intake) post-training had a positive main effect on shooting accuracy, F(2, 88) = 34.32, p < 0.001, ηp2 = 0.44, and shooting speed, F(1, 61) = 4.05, p = 0.35, ηp2 = 0.84. (4) Conclusions: Hydration level plays an important role in shooting accuracy and speed performance in adolescent handball players. Therefore, fluid intake integrated into training or match sessions may contribute to the maintenance and improvement of shooting performance.

Effects of concurrent in-season training on physiological functions required for top handball performance athletes

This study examined the physiological effects of combining contrast complex training (CCT) with either repeated short sprints (RSE) or high-intensity intervals (HIIT) on elite male handball players during the competitive season. The goal was to identify which training method more effectively enhances strength, endurance, and sprint performance. Fifteen elite handball players were divided into two groups during a 12-week training program, conducted alongside their regular handball practice. The RSE group (n = 8) performed 10 shuttle sprints (2x15m) with passive rest, while the HIIT group (n = 7) completed 5 repetitions of 30-second all-out sprints with directional changes. Both groups participated in CCT exercises, including squats at 90% of 1RM, jump squats at 50% of body weight, and drop jumps from 30 cm. Performance was assessed before and after the intervention using tests for jump squat rate of force development (RFD), 5-jump distance, 30m sprint, repeated shuttle sprint ability (RSSA), maximal squat strength, Yo-Yo intermittent recovery (YYIRT 1), and VO2max. Both groups significantly increased maximal squat strength, with the RSE group improving by 8.8% and the HIIT group by 7.4% (p < .01). The HIIT group showed a greater improvement in RFD (63.3% vs. 56.3%, p < .05). VO2max increased by about 2% in both groups. YYIRT 1 improved by 9.4% in the RSE group and 5.8% in the HIIT group. However, acceleration (5m sprint) declined in both groups, more notably in the RSE group (-5.7%). RSSA performance deteriorated in the RSE group, while the HIIT group significantly enhanced their fatigue resistance, with a 39.1% improvement in Sdec at RSA (p < .09). CCT increased strength and RFD but did not improve acceleration. HIIT was superior to RSE in maintaining or improving repeated sprint ability, making it the preferred method for elite handball players during the competitive season.

Same Same but Different: Why Both Sport-Specific Cutting Tasks and Generic Change-Of-Direction Tasks Might Need to Be Considered to Prevent ACL Injury

OBJECTIVE: To compare knee abduction moment (KAM) magnitudes between a generic 180° pivot turn (modified 505 change-of-direction test; m505) and a handball-specific sidestep cut, and to assess ranking consistency. Additionally, to examine the resultant ground reaction force (GRF) and its frontal plane moment arm to the knee to comprehend their contributions to KAM. STUDY DESIGN: Observational laboratory study. METHODS: High-level female handball players (n = 45) performed the m505 and handball-specific sidestep cut. Resultant GRF, its frontal plane moment arm to the knee, and KAM were obtained and subsequently compared between the tasks. Rank correlation coefficients were employed to assess if variables of both tasks are related. RESULTS: Peak KAM was similar for the m505 and the sidestep cut (1.79 (0.95 – 3.53) Nm/kg vs. 1.64 (0.34 – 3.60) Nm/kg; rB = .25; p = .14). The ranking of the players' peak KAM differed substantially ( rS = 0.26, p = .084), suggesting that different tasks could classify the same player with different injury risk. The m505 generated lower resultant GRF (24 ± 4 N/kg, 95% CI [23, 24] vs. 33 ± 9 N/kg, 95% CI [31, 35]; d = 1.30; p < .001) but longer frontal plane moment arms (7.8 ± 1.8 cm, 95% CI [7.3, 8.4] vs. 5.4 ± 1.5 cm, 95% CI: [5.0, 5.8]; d = 1.36; p < .001) than the sidestep cut. CONCLUSION: A difference in individual ACL injury risk assessment depending on movement type was revealed. While KAM magnitudes were similar across direction-change tasks, player rankings differed. The contributions of resultant GRF and frontal plane moment arms to peak KAM varied between tasks, underscoring the importance of task-specific and individualized injury prevention.

A Survey of Common Sports Injuries Among the Male Handball Players of Indian Universities

A Survey of Common Sports Injuries Among the Male Handball Players of Indian Universities

Acute Effects of Different Warm-Up Protocols on Jump Performance in Elite Male Italian Handball Players

The aim of the present study was to evaluate the acute effects of three different warm-up protocols on jump performance in elite male handball players. Warming up with a traditional (TR) set of exercise was compared with balance (BA) and unbalanced (UN) activation protocols. Thirty-two male handball players (age 24.2 ± 4.7 (m ± SD) y, weight 84.4 ± 8.5 kg, height 183.9 ± 7.3 cm) from two Italian first division National championship teams completed the three warm-up protocols in three different occasions and performed three countermovement jumps each with a 3 min rest. The jump height was evaluated from flight time. The players jumped an average of 40.7 ± 4.8 cm, 42.4 ± 4.9 cm, and 42.5 ± 5.0 cm in TR, BA, and UN conditions, respectively. A significant main effect (p < 0.001; η2 = 0.812) between the warm-up protocols for jump height was detected. A post hoc analysis showed that athletes performed significantly higher jumps under BA (p < 0.001) and UN (p < 0.001) conditions compared to performing a TR warm-up protocol. In conclusion, both BA and UN warm-up protocols induced significantly higher jump heights in elite male Italian handball players, compared to the traditional warm-up routine. The use of dynamic activation exercises enhance the neuromuscular properties of the warm-up compared to traditional protocols.

Effects of small-sided game training on lower limb explosive strength in handball players: a single-arm meta-analysis.

This meta-analysis systematically evaluates the influence of small-sided game (SSG) on the counter-movement jump (CMJ) height and 20-meter sprint capabilities of handball players. Systematic searches of PubMed, Web of Science, Cochrane Library, and China National Knowledge Infrastructure(CNKI) databases were performed up to February 2024. A total of 8 studies with 184 participants were included. Meta-analysis demonstrated significant improvements in CMJ (cm) in handball players (Weighted Mean Difference (WMD) = -1.06, 95% CI[-1.99, -0.12], Z = 2.22, P = 0.03). For the 20 m sprint capability, the results were WMD = -0.07, 95% CI[-0.14, 0.01], Z = 1.82, P = 0.07. Subgroup analysis by age: ≥19 years old WMD = -0.02, 95% CI[-0.08, 0.03], and <19 years old WMD = -0.10, 95% CI[-0.21, 0.00], indicating no significant impact on the 20-m (s) performance improvement. Gender subgroup analysis showed male WMD = -0.01, 95% CI[-0.08,0.07] and female WMD = -0.11, 95%CI[-0.19, -0.03; P < 0.05], suggesting better improvement in females. The present study reveals that SSG training has varying impacts on 20 m sprint performance among handball players of different ages and genders. Specifically, there is no significant improvement in the 20 m sprint performance between players aged <19 and ≥19, while female players show greater improvement in the 20-m (s) compared to male players. These differences could be attributed to the physiological, psychological, and adaptive training differences between athletes of different ages and genders. Although SSG plays an essential role in training handball players, particularly in enhancing lower limb explosive strength and overall game performance, it is recommended to combine SSG with other targeted strength and explosive power training to maximize the enhancement of lower limb explosive power in handball players. Comprehensive training can effectively improve the lower limb explosive strength of athletes while also addressing the development of other key athletic qualities to achieve the best training outcomes. Therefore, coaches should fully consider the individual differences and training needs of athletes when designing training plans, and reasonably allocate the proportion and sequence of SSG with other training methods to maximize training effectiveness.

Muscular robusticity and strength in the lower extremities in elite handball players

The relationship between structural and functional of parameters of skeletal muscles in young athletes needs further observations. The analyses of their age-group differences, sexual dimorphism, asymmetry characteristics in body regions, in sports having different pattern of physical loading could serve important information in this topic. 175 elite Hungarian handball players aged between 14 and 21 years were examined in 2023. Muscle mass component of the body segments was estimated by DEXA method and muscle thickness of the anterior mid-thigh region was measured by a new ultrasonic technique. The strength of knee extensor muscles was assessed by using an isokinetic protocol (Kineosystem dynamometer). A strong association between muscle robusticity and strength in the thigh region was confirmed in males, but not in females. Asymmetry in muscle mass reflected in the asymmetry in the knee extensor strength. A new predictive equation of muscle mass in the jumping leg and the total body from the muscle thickness in the anterior mid-thigh region of jumping leg was introduced. The exploration and understanding of asymmetric structural and functional adaptations can help athletes and trainers in planning the training and training interventions to reduce the risk of injuries.

Assessment of Glenohumeral Internal Rotation Deficit and Scapula Upward Rotation Differency Within Hungarian NB2Handball Players

The aim of our cross-sectional study was to assess the rotational range of motion of the shoulder joint and the scapula movement of Hungarian NBII handball players, to find out how many athletes may be affected by a rotational range of motion deficit. We also wanted to gain insight into whether players with GIRD report more pain. The study was conducted between September and October 2023. We studied 31 male handball players, all of whom participated in training sessions at least 3 times a week. The survey showed that more than half of the athletes were affected by some level of range of motion deficit. Of those assessed, 29% were affected by Glenohumeral Internal Rotation Deficit (GIRD) and 55% by Total Arc of Motion Deficit (TAMD). Those who had at least 15° of internal rotation deficit during pretesting had significantly less scapula upward rotation in the neutral shoulder, 60° abduction and 90° abduction positions. No significant difference was found in the 120° shoulder abduction position. For the non-dominant upper limb, no significant difference was found between the two groups. Athletes with GIRD reported significantly greater pain on the VAS scale than those without internal rotation deficit. Keywords: GIRD, handball players, shoulder joint, scapula up rotation, pain

Anatomic Risk Factors for Initial and Secondary Noncontact Anterior Cruciate Ligament Injury: A Prospective Cohort Study in 880 Female Elite Handball and Soccer Players.

Anterior cruciate ligament (ACL) injury is one of the most severe injuries for athletes. It is important to identify risk factors because a better understanding of injury causation can help inform athletes about risk and increase their understanding of and motivation for injury prevention. To investigate the relationship between anatomic factors and risk for future noncontact ACL injuries. Cohort study; Level of evidence, 2. A total of 870, excluding 9 players with a new contact ACL injury and a player with a new noncontact ACL injury just before the testing, female elite handball and soccer players-86 of whom had a history of ACL injury-underwent measurements of anthropometrics, alignment, joint laxity, and mobility, including leg length, knee alignment, knee anteroposterior laxity, generalized joint hypermobility, genu recurvatum, and hip anteversion. All ACL injuries among the tested players were recorded prospectively. Welch t tests and chi-square tests were used for comparison between the groups (new injury group, which sustained a new ACL injury in the follow-up period, and no new injury group). An overall 64 new noncontact ACL injuries were registered. No differences were found between athletes with and without a new ACL injury among most of the measured variables. However, static knee valgus was significantly higher in the new injury group than in the no new injury group among all players (mean difference [MD], 0.9°; P = .007), and this tendency was greater in players with a previous ACL injury (MD, 2.1°; P = .002). Players with secondary injury also had a higher degree of knee hyperextension when compared with those previously injured who did not have a secondary injury (MD, 1.6°; P = .007). The anatomic factors that we investigated had a weak or no association with risk for an index noncontact ACL injury. Increased static knee valgus was associated with an increased risk for noncontact ACL injury, in particular for secondary injury. Furthermore, hyperextension of the knee was a risk factor for secondary ACL injury.

Acute effects of different loading protocols upon performance and kinematics of 180 degrees change of direction

ABSTRACT This study examined the acute effects of different loading protocols on 180° change of direction (COD) performance in eleven male handball players. Participants performed a 10-0-5 COD test under seven conditions: without an external load, and with 3, 6, and 9 kg loads applied under two modes—assisted into the COD and resisted out of it and resisted into the COD and assisted out of it. While total COD time was not affected (p = 0.098; η2 = 0.16), significant phase effects were observed (p < 0.001; η2 ≥ 0.55). Loading protocols significantly influenced velocity, acceleration, and their distances from COD (p < 0.001; η2 ≥ 0.37). Significant phase effects were observed for all step kinematic variables (p ≤ 0.037; η2 ≥ 0.67), except contact time, and significant interaction (phase*condition) effects for all variables (p ≤ 0.004; η2 ≥ 0.08), except for step frequency. Assisted-resisted protocols increased deceleration demands through higher COD entry velocities, displaying fewer but longer steps in the acceleration phase and greater steps taken during the deceleration phase. Resisted-assisted protocols decreased deceleration demands due to lower COD entry velocities, displaying shorter, but more steps taken in the acceleration phase, and fewer steps taken in the deceleration phase. These findings suggest that assisted-resisted and resisted-assisted loading protocols can be used to selectively overload specific phases of COD performance.

One-Side Weight Sports and the Impact of Their Load on the Feet and the Occurrence of Posture Disorders in Professional Football and Handball Players

The aim of this study was to evaluate center of pressure (CoP) changes in unilateral sports and examine how these changes affect the athlete’s feet, ankles, knees or posture. The study sample consisted of 40 professional male players (age: 19.4 ± 2.08 years; height: 165.78 ± 4.92 cm; weight: 59.04 ± 4.02 kg; BMI: 21.57 ± 2.22; foot size: 40.9 ± 1.6), divided by type of sport into group H—handball (n: 20) and group F—football (n: 20). To evaluate the monitored parameters, we used the instrumental diagnostic techniques: 3D laser footscan, baropodometric platform FreeStep and 2D Videography. We found no significant differences between the groups in the loading of the right and left foot (F: 8.3 ± 4.22; H: 7.7 ± 6.1) (p = 0.410). We found a significant difference in the load on the front and back of the left (p = 0.0079) and right foot (p = 0.0210) depending on the type of sport performed. Maximum and mean values of CoP (g/cm2) showed statistically significant differences depending on the sport performed (p &lt; 0.0001). The shift in CoP (mm) from the norm depending on the sport performed was confirmed in the latero-lateral direction (p = 0.003), but not in the antero-posterior direction (p = 0.320). We found a difference in the angulation of the knees and heels depending on the sport played. Handball players showed higher knee varosity/valgosity (p = 0.015) and heel values than football players (p = 0.002). The handball players also confirmed a worse postural load and initial forward posture. The one-sided sports, handball and football, showed negative effects on the athlete’s movement system. These changes were more pronounced in handball players. Proper training programs should be applied in athletes’ daily routine to improve the negative effects of unilateral sports.

Інноваційні методологічні підходи до оцінки психофізичних здібностей гандболістів на етапі попередньої базової підготовки

The article deals with the psychophysical abilities of young handball players at the stage of preliminary basic training. Particular attention is paid to the analysis of the level of formation of such abilities as reaction speed, coordination of movements, concentration of attention and the ability to make decisions in stressful situations. The scientific relevance of the study is due to the need to improve training methods aimed at increasing the effectiveness of athletes' preparation for competitions. The purpose of the study is to analyze and evaluate the psychophysical abilities of young handball players, which will help to determine the effectiveness of the applied training methods and contribute to the development of new approaches to the training of athletes. Material and methods of research. Handball players at the stage of preliminary basic training (103 people) at the age of 15-16 years old, involved in the championship of Ukraine among boys, took part in the pedagogical experiment. To implement the goals and objectives of the study used a set of methods: theoretical analysis, synthesis and generalization; pedagogical observation; pedagogical testing; mathematical and statistical data processing. Research Results. It was found that the psychophysical abilities of young handball players who are at the stage of preliminary basic training correspond to a satisfactory level. However, in order to achieve high results in the future it is necessary to improve training programs taking into account the individual characteristics of each athlete. Analysis of the test results showed that the majority of handball players, both from the experimental and control groups, demonstrate similar results on the complex index of psychophysical abilities, which allowed us to conclude that there were no significant differences in the levels of development of psychophysical abilities between the groups at the beginning of the study. It was revealed that the average characteristics of different psychophysical tests in the majority of athletes correspond to a satisfactory level. For example, the speed of reaction to visual stimuli, reaction speed in game conditions, as well as the results of specialized handball tests showed that the level of formation of these abilities is sufficient for participation in competitions, but requires improvement to achieve high results. It is important to note that the highest average values of complex indicators of psychophysical abilities were observed in point guard players, which corresponds to the average level of formation. Line players also showed the results corresponding to the average level, while half-middle and edge players showed slightly lower values corresponding to the satisfactory level. Conclusions. The conducted study showed that at the stage of preliminary basic training most young handball players have a satisfactory level of development of psychophysical abilities, which indicates that there is a potential to improve their sports training by improving training methods. Given that different players demonstrate different levels of development of psychophysical abilities, especially among midfield and edge players, it is necessary to develop and implement individual training programs, which will optimize the training of each player in accordance with his individual characteristics and increase the overall effectiveness of the team.

Test–retest reliability of strength, power, agility, and sprint performance in female team handball players

ObjectivesThis study assessed the test–retest reliability of athletic performance tests in a cohort of trained Norwegian female handball players, as well as a sub-analysis of the test–retest reliability for naturally menstruating players. DesignEighteen handball players (naturally menstruating: n = 8) completed performance test batteries on three separate occasions. MethodsThe performance test battery included: a 1-repetition Smith machine back squat, maximal handgrip strength tests, counter-movement jumps, squat jumps, a modified agility T-test, and 15-m linear sprints. For the naturally menstruating players, the testing sessions were completed at three hormonally-distinct points within a menstrual cycle (i.e., early follicular, ovulation, and mid-luteal phases). Reliability statistics (intraclass correlations, standard error of measurement, minimum difference, and coefficient of variation) were calculated for each performance test. ResultsGood-to-excellent test–retest reliability was found for all performance measures (intraclass correlation2,1 point estimates = 0.82 to 0.94), although max squat jumps were somewhat lower (intraclass correlation2,1 = 0.75 [95 % confidence interval = 0.55, 0.88]). Subgroup analysis for naturally menstruating players also revealed consistently high reliability values for all tests (intraclass correlation2,1 point estimate = 0.83 to 0.74). ConclusionsThese reliability data support the periodic use of selected athletic tests in routine handball assessments, in order to identify changes in sporting performance and monitor player progress. As test reliability does not appear to be influenced by the menstrual cycle phase, coaches and sports practitioners may schedule testing sessions for all athletes, without concern of a confounding effect from menstrual phases.

Effects of a Specific Trunk and Shoulder Strength Training Program on Throwing Velocity and Accuracy: A Study Among Hungarian First-League Female Handball Players.

The aim of the study was to record shoulder and trunk stability of elite female handball players and to investigate their effect on throwing velocity and accuracy. 151 female handball players (9 teams in total) from the Hungarian first league participated in a mid-season conditional survey. The study included tests of trunk and shoulder stability, and measurements of factors affecting shoulder stability, as well as throwing speed and throwing accuracy. After the conditional survey, 18 players were selected for the intervention group (IG) and 18 players for the control group (CG). Significant relationships were found between the medial stability of the shoulder joint (Y-balance) and throwing accuracy (upper right corner) (r = 0.766; p < 0.001), throwing accuracy (upper left corner) (r = 0.729; p < 0.001), total throwing accuracy (r = 0.907; p < 0.001). The IG showed significant improvement in trunk stability (p < 0.001), shoulder joint stability (p < 0.001), throwing velocity (p < 0.001), and throwing accuracy (p = 0.002), compared to the CG. These findings support the idea that trunk and shoulder stability are related to throwing performance of female handball players. Measuring and training these aforementioned factors, particularly medial shoulder stability, may be a valuable adjunct to improving throwing accuracy and throwing velocity.

Psychological mood patterns among Jordanian handball players

The purpose of this study was to identify the prevailing mood patterns amongst handball players in Jordan. Therefore, this descriptive study was conducted on a sample consisting of (76) male handball players participating in the 2022/2023 Jordanian Handball League championship. The list of mood patterns for athletes was used as a data collection tool along with the following three statistical methods: Arithmetic mean, Standard deviations, and Two-Way ANOVA. The study results showed that the personal flexibility pattern emerged in first place with a high level and an arithmetic average of (2.3728). The cease operations pattern emerged second with a high level and an arithmetic average of (2.2556). The excitement operations pattern emerged third with a high level and an arithmetic average of (2.2257). Results relatively exhibited that there were no statistically significant differences in the level of mood patterns according to the variable of experience and player position amongst handball players. The researchers suggested a number of recommendations including, raising the awareness of handball players on psychological importance; in addition to mood preparation prior to the competitions. It is advised that players take courses and educational workshops that can be offered to athletes to enhance their psychological and physical performance Especially courses in regard to the excitement operations pattern, which obtained the lowest order among the three mood patterns.

Analysis of the relationship between upper body speed capacity and lower body strength of elite handball players specialized in winger position

Background and Study Aim. The physical demands of the winger position in elite handball require a unique combination of upper body speed and lower body strength. Therefore, identifying the optimal relationship between these two physical characteristics could improve performance for players in this role. This study aims to analyze the relationship between upper body speed capacity and lower body strength in elite handball players specializing in the winger position. Material and Methods. The study included 16 elite handball players specializing in the winger position from various teams in the National Handball League (Liga Zimbrilor). Four of these players were members of the Dinamo Bucharest team. Tests for evaluating the explosive strength of the lower limbs included the Squat Jump (SJ), Counter Movement Jump (CMJ), Counter Movement Jump with Free Arms (CMJb), and the maximum strength test (1RM) in squats. Specific technical training tests included triangular movement, a 30-meter sprint, and long-distance handball throws, focusing on speed and execution technique. Data analysis was conducted using KyPlot 6.0 software. Statistical indicators included median, standard deviation, coefficient of variation, and non-parametric Spearman correlation tests. Statistical significance was set at p &lt; 0.05. Results. The results show no statistically significant differences in lower limb strength between high-performance handball players (HPHP) and those specialized in the winger position (PSW) across various jump and squat tests (p &gt; 0.05). The Countermovement Jump (CMJ) test approached statistical significance (p = 0.084), while the CMJ with free arms (CMJb) and squat strength test did not show significant differences (p = 0.231 and p = 0.789, respectively). In the specific fitness tests, no significant differences were observed in the Triangle Movement test (p = 0.826), the 30-meter sprint (p = 0.404), or the handball throw test (p = 0.147). Correlation analysis indicated that squats and CMJb had positive correlations with improved performance in speed and distance tests, while CMJ showed a negative correlation with technical performance in agility tests. Conclusions. The findings suggest that lower limb strength and technical fitness are similar between elite handball players, regardless of specialization. This supports a unified training approach across player roles. However, targeted exercises like squats and CMJb may enhance specific performance aspects. These exercises improve dynamic strength and stability, which can benefit wingers' technical execution and speed.

Health problems and injury management in adolescent handball: the Safeplay one-season cohort study of 679 players

ObjectivesTo assess (1) the 1-year prevalence of previous shoulder, knee and ankle injuries; (2) the in-season prevalence proportion (prevalence) of injuries and illnesses, injury incidence rate (ir) and injury burden (product of ir and weeks with injuries); (3) initial injury management strategies.MethodsWe conducted a cohort study of 679 highest-division Danish handball players aged 14–18. Players self-reported past-year shoulder, knee and ankle injuries at baseline, and weekly information on any handball-related injuries (irrespective of time loss and medical attention), illnesses, exposure hours and injury management over 31 weeks.ResultsAt baseline, 46% (95% CI 42% to 49%) of the players reported a past-year shoulder, knee or ankle injury. The weekly average injury and illness prevalence was 21% (95% CI 19% to 23%) and 2% (95% CI 1.7% to 2.3%), respectively, and the ir was 9.4 (95% CI 8.7 to 10.2)/1000 hours. Females experienced the highest injury burden from knee injuries (ir: 1.7 (95% CI 1.3 to 2.2) × 6.7 (95% CI 4.7 to 8.7) weeks with injury/1000 hours), while males experienced the highest injury burden from shoulder injuries (ir: 1.3 (95% CI 1.0 to 1.7) × 5.7 (95% CI 3.6 to 7.8) weeks with injury/1000 hours). Health professionals were consulted in 58% (95% CI 54% to 62%) of injuries, players independently made the return to sport decision in 44% (95% CI 37% to 51%) of injury recurrences, and used analgesics, mainly (91% (95% CI 85% to 95%)) sourced from home, in 24% (95% CI 21% to 28%) of injuries.ConclusionAlmost half of highest-division adolescent Danish handball players reported a previous past-year shoulder, knee or ankle injury. Any time during the season, 21% reported an injury and 2% an illness. The highest injury burdens were from knee injuries in females and shoulder injuries in males. Health professionals often managed injuries, but players frequently made return to sport decisions independently and commonly used analgesics sourced from home.

Identifying factors affecting sports achievement and endurance using artificial intelligence

Abstract Introduction Sports achievements and performance are not solely based on outstanding endurance, especially in tactical and technical sports. Artificial intelligence (AI) can help us to identify correlations that can contribute to the successful preparation of athletes. Purpose Our aim was to further analyze and evaluate our previously initiated AI-based sports performance studies, identifying the parameters that determine athletes’ achievement and endurance. Methods First, sports cardiology screening was performed in all athletes containing the following examinations: patient’s history, ECG, laboratory test, body composition analysis, echocardiography and cardiopulmonary exercise testing. A database from the sports cardiology screening results was established. Then, we created two scoring systems based on the best ever result (Achievement Score) and the performance on the cardiopulmonary exercise test (Endurance Score). We identified the most important influencing factors using a neural network and characterized the strength of the variables using Shappley Additive Explanation (SHAP) values. Results We examined 1932 tests of 891 athletes and the AI analysis included 917 tests of 546 athletes (20.2±6.2 years, males: 397, 72.7%). Majority of the examined athletes were swimmers (27.4%), followed by basketball players (21.8%), water polo players (15.2%), handball players (13.3%) and football players (13.1%). The most important Achievement Score determinants were the weekly training hours (SHAP=0.27), training years (SHAP=0.26) and the age (SHAP=0.15). Meanwhile, Endurance Score was mainly affected by skeletal muscle mass (SHAP=0.85), weight (SHAP=0.6) and peak heart rate during exercise (SHAP=0.32). Our results were validated on a test population (N=102) and in the Achievement Score the mean absolute error (MAE) was 0.64, the determination coefficient (R2) was 0.56, in Endurance Score the MAE was 0.84 and the R2 was 0.71. Conclusion Based on our results, while endurance is mainly determined by the athlete’s physical characteristics, in athletic achievement experience is more important. With our scoring systems the athlete’s achievement and endurance can be predicted well.

Equal Effects of Low- and Moderate-Volume Supplementary Plyometric Training on Sprint, Change of Direction Ability, and Lower-Limb Power in Preadolescent Female Handball Players.

Background: This study compared the effects of low- and moderate-volume supplementary plyometric training in preadolescent female handball players. Methods: Thirty-nine preadolescent handball players (age: 12.9 ± 0.5 years, maturity offset: -1.50 ± 0.56 years) were randomly assigned into three groups: low-volume plyometric training group (LPT, n = 12); moderate-volume plyometric training group (MPT, n = 15); and control group (CG, n = 12). The supplementary plyometric training program was performed twice per week for 10 weeks, along with normal training (3 times/week). Each supplementary session included two upper- and three lower-body exercises performed for two sets (LPT, 36-54 foot contacts, duration 12 min) or four sets (MPT, 72-108 foot contacts, duration 24 min). The CG performed technical handball drills for 20 min. Results: Compared with the control group, both LPT and MPT resulted in similar improvements in modified T-test performance (15.1% and 18.6%, p < 0.01, respectively); linear sprint performance over 5, 10, and 20 m (between 5.1% and 8.8%, p = 0.02 to 0.001); countermovement jump (28.0% and 22.1%, p < 0.05, respectively); and standing long jump (12.6% and 12.5%, p = 0.024, respectively). Handgrip strength and overarm shot ball velocity improved similarly in all groups (CG, MPT, and LPT), by 8-11% (p < 0.01). Conclusions: Very-low-volume supplementary plyometric training performed for 12 min per session for two sessions per week results in considerable improvements in running speed, change of direction ability, and leg power and is as effective as a moderate-volume program. These findings are important for pre-adolescent female team sports players, who may benefit from a minimal but effective supplementary training, resulting in large benefits in leg speed and power.

The Effect of Reactive Neuromuscular Training versus General Warm-up on Proprioception and Balance in Female Handball Players with Rounded Shoulder: A Controlled Laboratory Study

Background: This study aimed to compare the immediate effects of a session of reactive neuromuscular training (RNT) with warming-up exercises on shoulder proprioception and dynamic balance in female handball players with shoulder impingement. Methods: In this controlled laboratory study, 18 female adolescent handball players from 14 to 18 years old were recruited from Samen City, Iran. The participants participated once in the warm-up routine program and once in the RNT program. Before and after each exercise program, shoulder proprioception was measured by photogrammetry and dynamic balance of the upper limb was measured using the Wye balance test. The paired t-tests, with a significance level of 0.05, were employed to compare pre-test and post-test data. Results: Both exercise protocols had no significant effects on shoulder repositioning error (P &gt; 0.05). However, participation in both exercise programs resulted in a significant improvement in the dynamic balance score of the upper limbs of the athletes (P &lt; 0.001). Moreover, no significant differences were observed between the effect of routine handball exercises and the effect of RNT exercises on shoulder repositioning and dynamic balance in female handball players (P &gt; 0.05). Conclusion: It seems that routine warm-up exercises and RNT could not improve proprioception in the shoulders of student- athletes with round shoulders. However, both training methods caused a significant improvement in the dynamic balance of the upper limb, although there was no significant difference between the effects of the two methods.