Effects of single and repeated bouts of flywheel exercise on jump performance and muscle damage in athletes and non athletes.

BACKGROUND: Although recent studies have investigated the effects of flywheel (FW) training on muscle function, the effects of transient FW exercise on jump performance in athletes are unknown. This study examined the effects of single and repeated bouts of FW squat exercises on jump performance and muscle damage in male collegiate basketball players. METHODS: The participants were 10 healthy college-age men (nonathletes) and 11 male basketball players (athletes). The intervention involved 100 squat exercises (10 repetitions × 10 sets) using an FW device. To examine the repeated-bout effects, the protocol was conducted again after a 2-week interval. Squat jumps, countermovement jumps, drop jumps, and rebound jumps were evaluated as jump performance, while isometric maximal voluntary contraction (MVC) torque in knee extension, muscle soreness, range of motion, thigh circumference, muscle thickness, and echo intensity were evaluated as markers of muscle damage. Measurements were taken at baseline, immediately after exercise, 24 h later, and 72 h later. RESULTS: The jump performance of nonathletes decreased after exercise (p < 0.05), while that of the athletes did not. The results were similar for muscle soreness. MVC torque decreased significantly after the first exercise in both groups (p < 0.05) and was significantly lower in the nonathletes versus athletes. Significant repeated-bout effects were found for muscle soreness in nonathletes but not athletes. CONCLUSIONS: These results suggest that a single bout of FW exercise reduces jump performance in male nonathletes but not basketball players.

Training methods and evaluation of basketball players' agility quality: A systematic review.

OBJECTIVE: Agility refers to the technical skills and abilities required by athletes to quickly react and adjust direction, speed, or movement patterns when faced with stimuli. This article provides a comprehensive review and evaluation of agility training methods for basketball players, offering valuable insights and references for scientifically enhancing their agility training. METHOD: Research literature published from January 1, 2000, to April 1, 2023, was searched in the Web of Science Core Collection, PubMed, and EBSCO databases with basketball, agility, and training as keywords. A total of 489 articles were initially identified. Based on predefined inclusion and exclusion criteria, including the removal of duplicate articles, non-English publications, and conference papers, a total of 463 articles were excluded. Ultimately, 26 articles that met the specified criteria were included for analysis in this study. The researchers utilized the PEDro quality evaluation screening scoring system to assess the quality of the final included literature. RESULT: 26 articles were included, with an average quality evaluation score of 4.5 points (3-7 points). Among them, the average training time for reaction ability (5 articles) is 5 weeks (ranging from 3 to 8 weeks), involving a total of 150 participantsa，nd the agility quality is improved by 7.2 %-19 %; The average training time for speed quality (5 articles) is 6 weeks (ranging from 4 to 8 weeks), involving a total of 151 participants，and the agility quality is improved by 1.2 %-14.4 %; The average training time for strength quality (4 articles) is 6 weeks (ranging from 4 to 8 weeks), involving a total of 57 participants， and the agility quality is improved by 1.41 %-10.33 %; The average training time for plyometrics (12 articles) is 6 weeks (ranging from 1 to 8 weeks), involving a total of 195 participants，with an increase in agility by 2.34 %-6.79 %. CONCLUSION: (1) The effect of simple reaction ability, speed, and strength training on improving the agility quality of basketball players is limited. In the actual process, the above training methods need to be combined to maximize the training effect, such as diversified speed training combined with different forms of reaction ability, strength training, etc. (2) Plyometric training has a high intensity of muscle stimulation, which can promote the agility quality of basketball players by improving the joint stability, neuromuscular adaptability as well as coordination and consistency between muscles. However, young basketball players must carefully consider exercise mode, load intensity, and other factors when implementing plyometric training.

Remodeling of Lumbar Spinal Osteoid Osteoma Resected With Microscopic Surgery in a 15-Year-Old Basketball Player: A Case Report.

This case report focuses on a 15-year-old competitive-level high school basketball player who experienced chronic low back pain. Diagnostic imaging revealed osteoid osteoma in the L5 posterior element, causing osteosclerotic deformity of the left lamina and more inferior facet. To return him to the condition of sports activity, less invasive surgery of microscopic tumor resection with autologous bone grafting was planned instead of CT-guided ablation, which can cause thermal injury to nearby tissues. This procedure could preserve spinal structures, including the facet, pedicle, and paravertebral muscles. The day after surgery, the patient experienced a complete resolution of lower back pain. He gradually resumed light exercise two months postoperatively. Three-month follow-up CT imaging revealed bone remodeling at the resection site, to return to complete basketball activities. Over five years, no tumor recurrence or symptoms were observed, and he maintained his competitive activity level.

The Effects of Core Stabilization Trunk Muscle Fatigue on Lower Limb Stiffness of Basketball Players.

Core stability is the ability to control the position and motion of the trunk over the pelvis and legs to allow the optimum production and transfer of force to the terminal segment in sporting activities. The effect of fatigue, especially core muscle fatigue, on stiffness as a performance index requires more study. This research aimed to investigate the effect of the core stabilization muscles' fatigue on lower limb stiffness during hopping. Thirty active basketball players participated in this study (age: 20.90 ± 1.49 years; weight: 60.30 ± 3.10 kg; height: 163.2 ± 5.04 cm). The hopping test (15 jumps) was performed before and after the fatigue protocol in three states including at a preferred (no frequency control), maximum, and 2.2 Hz frequency on the force plate. The stiffness of the lower extremities was measured before and after the fatigue protocol. The results of the dependent t-test showed core muscle fatigue led to reduced lower extremity stiffness under all three hopping-test conditions by 15.3-15.9% (p ≤ 0.005). It seems that core muscle function affects lower extremity stiffness, and can function as a performance index in athletes. Although performed in healthy volunteers, this study may have implications for injury prevention, highlighting the necessity to perform interspersed endurance training using the different body parts of the kinetic chain.

Visual search strategies of performance monitoring used in action anticipation of basketball players.

INTRODUCTION: Numerous studies have found that expert players anticipate better than novices. If more accurate prediction represents performance monitoring of experts, what are the advantages of elite basketball players in identifying and processing available cues? There is still a lack of sufficient evidence. This study examined the visual search in basketball players and explored the performance monitoring of action anticipation, adopting an expert-novice paradigm and eye-movement technology. METHODS: Forty basketball players were recruited in this study: 20 in the expert group and 20 in the novice group. Participants were asked to predict the outcome of videotaped basketball throws and their accuracy and eye-movement characteristics were record. RESULTS: The accuracy of the expert was significantly higher than that of the novice. The experts were able to instantly search and identify important cues in anticipation, and the gaze area of the experts was concentrated on the area of interest of the body. Additionally, the expert group showed long, repetitive, and rapid visual search of vital information, and improved their performance of the task. CONCLUSION: The experts could monitor the performance of prediction by grabbing vital shooting information (such as the body of a player). The results suggest the athletes and coaches that if they want to improve the ability of prediction, it may be useful to shift their focus of attention from ball trajectory to body action.

Comparative Efficacy of Vibration foam Rolling and Cold Water Immersion in Amateur Basketball Players after a Simulated Load of Basketball Game.

To compare the efficacy of different recovery strategies (sitting; cold water immersion, CWI; vibration foam rolling, VFR) on the lower extremities of amateur basketball players after the simulated load of a basketball game, we assessed the power, agility, and dynamic balance before and after interventions. Ten amateur basketball players alternately underwent 12 min of sitting, 12 min of CWI at 5 °C, and 12 min of VFR. The power, agility, and dynamic balance were measured immediately post-warm-up, immediately post-game, immediately post-intervention, 1 h after interventions, and 24 h after interventions. To simulate the load of a basketball game, specific movements were designed and implemented. Jump height was measured using a Kistler force plate. Reaction time and dynamic balance score were assessed using the Pavigym agility response system and the Y balance test, respectively. The data were analyzed with a two-way repeated measures analysis of variance (ANOVA). The results showed that the vertical jump height significantly decreased after the CWI intervention compared to the CON and VFR groups (p < 0.001). At 1 h after the intervention, the vertical jump height in the CON group showed delayed recovery compared to the CWI and VFR groups (p = 0.007; p < 0.001). At 24 h after the intervention, the vertical jump height in the CWI group further increased and was significantly different from the CON and VFR groups (p < 0.001; p = 0.005). Additionally, reaction times significantly increased immediately after the CWI intervention (p = 0.004) but showed further recovery at 24 h compared to the CON group (p < 0.001). The dynamic balance score significantly rebounded after the CWI intervention compared to the CON group (p = 0.021), with further improvement at 24 h (p < 0.001). CWI initially showed negative effects, but over time, its recovery effect was superior and more long-lasting. VFR had the best immediate effect on lower limb recovery after the game.

Acute effects of foam rolling and dynamic stretching on angle-specific change of direction ability, flexibility and reactive strength in male basketball players.

The purpose of our study was to determine the acute effects of dynamic stretching (DS), foam rolling (FR) and foam rolling combined with dynamic stretching (Combo) protocols on angle-specific change of direction (COD) ability, drop jump (DJ) performance and flexibility. Using a counterbalance crossover study design, eleven male basketball collegiate players (20.7 ± 0.6 years) were randomly assigned to one of the four protocols - control (CON), DS, FR, Combo - for each session, for a total of four sessions. A more aggressive foam cylinder with raised nodules, which is thought to be effective in stimulating the deep layer of muscle tissue, was used to observe for changes in their performance during sit and reach (SAR), DJ and COD tasks in 45 and 180 degrees. One-way repeated measures ANOVA was used to identify differences of each variable separately between interventions. The SAR after three interventions compared to the CON was significantly improved (F (3,30) = 5.903, P = 0.003, η2 = 0.371). In the 505 test, both limbs failed to show a significant improvement in COD deficit. The non-dominant limb showed a significant improvement of 6.4% after FR when performing the Y-shaped agility (F (3,30) = 4.962, P = 0.0065 < 0.05, η2 = 0.332). In the DJ, the reactive strength index and contact time changed significantly by 17.5% and -17.5% (η2 = 0.518, η2 = 0.571), respectively, immediately after FR. The current research suggested that FR may have an enhancing effect on COD speed in a 45° cutting task and neuromuscular function, while having the potential to improve non-dominant limb deficits in both COD tasks. In contrast, the Combo warm-up protocol did not produce a cumulative effect, suggesting the need for coaches to remain cautious about excessive warm-up duration.

Effect of kinesio taping intervention on the muscle strength and balance of college basketball players with functional ankle instability.

Objective: The aim of this study was to investigate the effects of acute Kinesio Taping (KT) intervention on the muscle strength and balance ability of college basketball players with functional ankle instability (FAI). Methods: Thirty college basketball players with FAI were treated with acute KT to test the changes in their muscle strength and balance ability. Results: After acute KT intervention, the ankle dorsiflexion moment and the ankle plantar flexion moment increased by 34% and 19.9%, respectively. The stable plane test with the subjects' eyes open decreased by 1%, whereas that with the subjects' eyes closed decreased by 1.1%. The swaying environment test with the subjects' eyes open increased by 2.4%. The swaying plane test with the subjects' eyes open increased by 5.1%, whereas that with the subjects' eyes closed increased by 16.2%. The swaying environment test with the subjects' eyes open plus the use of a plane increased by 12.1%. Conclusion: KT can increase the isokinetic strength of the ankle dorsum muscle and plantar flexion of college basketball players with FAI. The effect of KT in the static balance test was weaker than that in the dynamic balance test. The findings indicate that KT can significantly improve the balance ability of college basketball players with FAI during dynamic sports.

Team ball sport experience minimizes sex difference in visual attention.

Simultaneous tracking of the position of the ball and player locations and activities places high demands on visual attention in team ball sport athletes. Owing to their extensive sports training, these athletes may be expected to exhibit visual attention skills superior to non-athletes; however, the results of studies examining this are inconsistent. Thus, the first aim of this study was to assess the impact of participating in a team ball sport on visual attention. There is limited empirical evidence indicating a sex difference in visual attention, and few studies have reported on visual attention in male and female athletes. Thus, the second aim of this study was to determine whether team ball sport experience affected any sex differences in visual attention. In total, 44 highly skilled basketball players-22 men (mean age: 21.86 ± 2.15 years) with a mean (SD) of 8.46 (2.92) years training experience and 22 women (mean age: 21.32 ± 1.58 years) with a mean (SD) of 8.22 (2.44) years of training experience-and 44 non-athletic undergraduate college students-22 men (mean age: 21.62 ± 1.88 years) and 22 women (mean age: 21.55 ± 1.72 years)-were recruited and completed this study. Visual attention was measured by using the multiple object tracking (MOT) task. Skilled basketball players showed superior tracking accuracy to non-athletic college students on the MOT task. A significant sex difference was found only among the non-athletic college students, with better tracking accuracy for men than for women on the MOT task. By contrast, no significant sex difference was observed among the skilled basketball players for tracking accuracy on the MOT task. These findings indicated that team ball sport training may enhance visual attention as assessed by tracking accuracy. Given that the male and female basketball players in this study had similar training experience and game performance demands, long-term team ball sport experience appeared to minimize the sex difference in visual attention found among non-athletic students.

Characteristic MRI findings of the shoulder, elbow, and wrist joints in elite wheelchair basketball players.

BACKGROUND: The health of wheelchair users' upper limbs is directly related to their quality of life. Moreover, para-sport athletes are subjected to a dual load on their upper extremities from competition and daily life, making it even more critical to maintain upper extremity health. This study aimed to investigate the characteristics of joint disorders in elite wheelchair basketball players using magnetic resonance imaging (MRI). METHODS: We scanned MRI images of the bilateral shoulders, elbows, and wrist joints of ten elite wheelchair basketball players and ten general wheelchair users. The elite wheelchair players were athletes who underwent at our institution medical checkup of the candidates for the national team for the international women's tournament and who agreed to this research purpose. The general wheelchair players were recruited from wheelchair users in their 20s and 30s who had no daily exercise habits and who agreed to the study objectives. Two radiologists interpreted the MRI images and diagnosed the diseases of each joint. We compared the number of lesions between the two groups. We used Fisher's exact test to determine whether the lesions diagnosed by MRI were specific to wheelchair basketball players. The significance threshold was set at P < 0.05. RESULTS: Elite wheelchair basketball players had significantly more right-sided, left-sided and bilateral latero-posterior lesions, which are cysts found on the lateral-posterior corner of the capitulum of the humerus than did general wheelchair users (P < 0.05). Severe damage to the right triangular fibrocartilage complex was also observed more frequently (P < 0.05) in wheelchair basketball players. CONCLUSIONS: We believe that the patients' tendency to fall forward in the wheelchair hitting both hands on the ground, thereby injuring the triangular fibrocartilage complex and locking the lateral elbow, may be the cause of the characteristic findings on MRI. High-speed wheelchair operation was also considered a cause of severe triangular fibrocartilage complex injuries. This study's insights can be useful for future solutions to extend players' careers.

Effects of Interactive Music Tempo with Heart Rate Feedback on Physio-Psychological Responses of Basketball Players.

This paper introduces an interactive music tempo control with closed-loop heart rate feedback to yield a sportsperson with better physio-psychological states. A total of 23 participants (13 men, 10 women; 16−32 years, mean = 20.04 years) who are professionals or school team members further guide a sportsperson to amend their physical tempo to harmonize their psychological and physical states. The self-tuning mechanism between the surroundings and the human can be amplified using interactive music tempo control. The experiments showed that listening to interactive music had a significant effect on the heart rate and rating of perceived exertion (RPE) of the basketball player compared to those listening to asynchronous music or no music during exercise (p < 0.01). Synchronized interactive music allows athletes to increase their heart rate and decrease RPE during exercise and does not require a multitude of preplanned playlists. All self-selected songs can be converted into sports-oriented music using algorithms. The algorithms of synchronous and asynchronous modes in this study can be adjusted and applied to other sports fields or recovery after exercise. In the future, other musical parameters should be adjusted in real-time based on physiological signals, such as tonality, beats, chords, and orchestration.

Positional Differences in Physique, Physical Strength, and Lower Extremity Stability in Korean Male Elite High School Basketball Athletes.

No studies have measured the physical strength and lower extremity stability of elite male high school basketball players. This study aimed to measure the physique, physical strength, and lower extremity stability of such athletes in Korea and analyze the differences according to their play positions. Overall, 204 male elite basketball players participated and were classified as guard (n = 97), forward (n = 69), and center (n = 38) according to their main playing position. All sub-variables of physique were significantly higher in the forward and center groups than in the guard group, and were significantly higher in the center group than in the forward group. Strength was significantly higher in the forward and center groups than in the guard group. Agility and speed were significantly faster in the guard group than in the forward and center groups. Y-balance analysis showed that the composite score of both feet tended to be higher in the order of center, forward, and guard, and it was significantly higher in the guard group than in the center group. These results could be used as basic data for selecting players, determining positions, and setting specific training goals for players of each position to improve physical strength and prevent injuries.

The Mediated Effect of Sports Confidence on Competitive State Anxiety and Perceived Performance of Basketball Game.

This study aimed to determine the mediating effect of sports confidence on competitive state anxiety and perceived performance basketball game. This study was conducted on 219 Korean basketball players, including 101 men and 118 women who were either high school students (42), university students (96), or professional basketball players (81). The Sources of Sport Confidence Questionnaire (SSCQ), Revised Competitive State Anxiety Inventory-2 (CSAI-2R), and the perceived performance questionnaire was used to measure sports confidence, competitive state anxiety, and perceived performance, respectively. The results showed that self-confidence (ß = z 0.552, p < 0.001) and the coaches' leadership (ß = 0.552, p < 0.001) were found to be factors that influenced perceived performance. The perceived performance showed a positive correlation with all the sports confidence subscales and self-confidence of the competitive state anxiety subscales (p < 0.01). However, it showed a negative correlation with cognitive and somatic anxiety (p < 0.01). Sports confidence had a statistically significant mediating effect between somatic anxiety and perceived performance and a statistically significant mediating effect between self-confidence and perceived performance (p < 0.05). It appeared that sports confidence and competitive state anxiety had a statistically significant effect on perceived.

The torque analysis of lower limbin basketball based on sEMG signal.

OBJECTIVE: To assess the advantage of using the sEMG signal for establishing the mathematical model of lower limb movement and evaluating the improvement in the jumping ability of basketball players as the ultimate target strength. Also, to evaluate its use it in the training of lower limb strengthening of basketball players. METHODS: In this study conducted from March 1, 2019 to June 1, 2019, 30 professional male basketball players were selected as the subjects, gait analysis was carried out when they finished the three-step layup in 15 minutes. Acquisition and noise reduction process of the collected sEMG signals were first filtered by band-pass filter to eliminate the noise outside the frequency, then suppressed by the spectral interpolation method, and finally subjected to wavelet transformation. RESULTS: The lower limb muscle group was activated once in a cycle. The anterior and posterior thigh muscle groups, and anterior Tibial muscles were activated in the early stage, increased to the maximum value and then decreased gradually; the long and short muscles attached to the fibula were activated in the middle stage, and decreased rapidly. CONCLUSIONS: The research results of sEMG signal showed that the torque intensity of the front and back thigh muscles is greater than that of other muscle groups. Strengthening the training is helpful to enhance the jumping ability of basketball players.

Dynamic visual attention characteristics and their relationship to match performance in skilled basketball players.

BACKGROUND: Dynamic visual attention is important in basketball because it may affect the performance of players and thus the match outcome. The goals of this study were to investigate the difference in dynamic visual attention characteristics between highly skilled basketball players and nonathletic college students and to explore the relationship between visual attention and game-related performance among the basketball players. METHODS: In total, 24 highly skilled basketball players and 24 nonathletic college students participated in a multiple object tracking task. The task was conducted so that either the number of targets that were visually tracked or the speed at which a given number of tracked targets moved was altered to examine the difference in dynamic visual attention characteristics between the basketball players and nonathletic college students. The relationship between visual tracking speed (VTS) and game-related statistics, including assists, steals, mistakes, fouls and points scored recorded for every match during the season, was assessed among the basketball players by using Pearson correlations. RESULTS: A significant main effect of target tracking load was observed (P < 0.001), with visual tracking performance significantly decreased as target number increased. In addition, the speed at which the targets moved had a significant effect on visual tracking performance (P < 0.001), with tracking performance significantly decreased as target speed increased. However, no significant difference was observed in the abilities of basketball players and nonathletic college students to simultaneously track up to six targets. By contrast, a significant interaction between group and target speed was found (P < 0.001), with the visual tracking accuracy of basketball players significantly greater than that of college students at the higher target speeds examined (P < 0.001). Among basketball players, there were positive, large, and statistically significant correlations in the accuracy in VTS trials and the number of assists (P < 0.001) and between the accuracy in VTS trials and the number of steals (P < 0.001). CONCLUSION: The advantage of skilled basketball players to handle dynamic visual information in a multiple object tracking task was not attributable to the target number but to the target speed. Those athletes with greater dynamic visual attention were more likely to successfully assist or to steal the ball, enhancing performance of the athlete as well as contributing to a more successful team match. These findings may inform basketball training programs to improve player and team performances during matches.

Foot Alignment in Symptomatic National Basketball Association Players Using Weightbearing Cone Beam Computed Tomography.

BACKGROUND: Weightbearing cone beam computed tomography (WB CBCT) allows detailed 3-dimensional imaging of the foot and ankle in a weightbearing state and provides improved accuracy and reliability of foot alignment measures, especially when compared with conventional radiographic views. PURPOSE: To describe the foot alignment in National Basketball Association (NBA) players with different symptomatic foot and ankle injuries using WB CBCT and to determine if any predominant morphotype would be identified. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 45 active NBA players (mean age, 24.4 years [range, 20-34 years]; N = 54 feet [29 right, 25 left]) were assessed using WB CBCT. Measurements included the following: (1) foot and ankle offset (FAO), (2) calcaneal offset (CO), (3) hindfoot alignment angle (HAA), (4) angle between the inferior and superior facets of the talus (Inftal-Suptal), (5) angle between the inferior facet of the talus and the horizontal floor line (Inftal-Hor), (6) forefoot arch angle (FAA), (7) navicular-to-floor distance, and (8) medial cuneiform-to-floor distance. Measurements were then compared with values available in the literature for a "normal" foot morphotype. RESULTS: Among the 54 feet, the mean FAO was 0.48% (95% CI, -0.25% to 1.21%), the mean CO was 1.18 mm (95% CI, -0.50 to 2.87 mm), and the mean HAA was 1.42° (95% CI, -0.80° to 3.65°). The mean Inftal-Suptal angle was 5.31° (95% CI, 3.50°-7.12°), while the mean Inftal-Hor angle was 4.04° (95% CI, 2.56°-5.51°). The mean FAA was 15.84° (95% CI, 14.73°-16.92°), the mean navicular-to-floor distance was 38.30 mm (95% CI, 36.19-40.42 mm), and the mean medial cuneiform-to-floor distance was 26.79 mm (95% CI, 25.30-28.28 mm). None of these values were found to be significantly different when comparing forwards, guards, and centers. CONCLUSION: NBA players presenting with symptomatic foot and ankle injuries had a fairly "normal" foot morphology, with a tendency toward a varus hindfoot and a high-arched morphotype. No significant differences were found between players based on their position on the court. WB CBCT may help to shed light on anatomic risk factors for common injuries in professional players and may aid in the planning of specific prevention programs.

Comparison of the effects of static stretching on range of motion and jump height between quadriceps, hamstrings and triceps surae in collegiate basketball players.

OBJECTIVES: The purpose of the present study was to compare the effects of static stretching (SS) on the range of motion and vertical jump height between the quadriceps, hamstrings and triceps surae in collegiate basketball players. METHODS: Fourteen male collegiate basketball players (20.2±0.7 years, 179.0±5.0 cm, 71.9±8.3 kg) underwent 5 min of SS for the quadriceps, hamstrings and triceps surae, in random order. Before and after each stretch, the range of motion (ROM) and vertical jump height were measured. RESULTS: ROM of the quadriceps, hamstrings and triceps surae were increased without any difference of relative change in the range. The vertical jump height showed no change after SS of the quadriceps and hamstrings, while it decreased after SS of the triceps surae (p<0.05). CONCLUSION: These results suggested that SS for the triceps surae may have a large impact on jump performance.

Poor static balance is a risk factor for non-contact anterior cruciate ligament injury.

BACKGROUND: This prospective study aimed to investigate the relationship between static balance and the incidence of non-contact anterior cruciate ligament (ACL) injury in female high school athletes. METHODS: This study included 276 female high school handball or basketball players. At the time of admission, each subject's static balance was measured with a gravicorder, and the incidence of non-contact ACL injury was investigated in the 3 years until the student graduated. The measured parameters of postural sway were locus length per time (the distance that a center of gravity of the foot pressure moves per second) and environmental area (AR: the area surrounded by the integumentary covering of the trace of the center of gravity). Twenty-seven players (9.8%) experienced an ACL injury during the 3-year observation period. Twenty-four injured players sustained a non-contact injury and three injured players sustained a contact injury. In this study, the three contact injury players were excluded. We compared the differences in the static balance between injured and uninjured players. RESULTS: The locus length per time was significantly longer in injured than in uninjured players (p = 0.046). Though there was no statistically significant difference between the two groups in AR (p = 0.190), AR tended to be larger in the ACL injured group. CONCLUSIONS: This result shows that poor static balance is a risk factor for non-contact ACL injury.

Effects of Reach Balance Exercise on Toe Grip Strength and Balance in College Basketball Players.

OBJECTIVE: This study was conducted to clarify the ground reaction force exerted on the foot during athletic movements and to demonstrate the effects of reach balance training (RB-T) on toe grip strength as an injury prevention exercise. METHODS: RB-T was undertaken for 2 weeks by 11 male college basketball players and 22 healthy male college students (including 10 participants in the control group). The vertical ground reaction forces during athletic movements were measured using ground reaction force meters. Before and after RB-T intervention, toe grip strength was measured with a toe grip strength meter, and distances of the center of pressure (COP) to the center of the foot during movement were measured using a three-dimensional motion analyzer. RESULTS: The vertical ground reaction force during athletic movement was highest during take-off and decreased in the following order: single-leg front landing, single-leg lateral landing, and turning. The toe grip strength of the BT group and the T group increased after RB-T intervention. For the BT group, RB-T also tended to decrease the COP lateral distance on turning in the dominant leg and the COP front distance on turning and take-off in both legs. CONCLUSION: RB-T could improve the toe grip strength and stabilize the COP position.