Purpose: Shoulder injuries are common in CrossFit athletes, with scapular dysfunction playing a key role. Given the scapula’s key role in force transmission and shoulder stability, this study aimed to investigate the effect of a corrective exercise program on improving shoulder stability in CrossFit athletes. Methods: This quasi-experimental study initially enrolled 26 male CrossFit athletes aged 25–30 years recruited via purposive sampling from local clubs and selected based on predefined eligibility criteria. An a priori power analysis (G*Power software, version 3.1; effect size=0.54, α=0.05, power=0.80) indicated a minimum of 24 participants; to accommodate approximately 10% attrition, 26 were enrolled and equally allocated to intervention and control groups (13/13). Scapular stability was assessed with the Davis Test pre- and post-intervention. Data normality was examined with the Shapiro–Wilk test; within-group changes were analyzed using paired t-tests, and between-group effects with analysis of covariance (ANCOVA) (adjusting for pretest values). Two control participants were lost to follow-up; analyses were completed on 24 athletes. All analyses were performed using SPSS software, version 26 (α=0.05). Results: The intervention group showed significant improvements in scapular stability, with Davis test record increasing by 8.4% and power output increasing by 8.4% (P<0.01), while the control group showed no significant changes (P>0.05). Analysis of covariance (ANCOVA) confirmed significant between-group differences in both Davis Test record (adjusted Mean±SD: 13.42±1.20 vs 12.67±1.65; partial η²=0.205) and power output (adjusted Mean±SD: 1138.23±98.67 vs 1050.76±134.55; partial η²=0.241; P<0.05), demonstrating the effectiveness of the corrective exercise program. Conclusion: The present study demonstrated that the selected corrective exercises can improve scapular function and enhance shoulder stability. This improvement contributes to increased shoulder strength and power, ultimately contributing to the improvment of movement dysfunctions.

BACKGROUND:Hamstring injuries are common in soccer, and fatigue-induced alterations in core function may influence neuromuscular control and hamstring performance. OBJECTIVE:To investigate the acute effects of a core endurance fatigue protocol on isokinetic hamstring strength and active knee extension (AKE) range of motion in male soccer players. METHODS:Thirty male soccer players participated in this pre-post experimental study. Their mean age was 25 ± 3.2 years, mean height was 179.4 ± 6.6 cm, mean weight was 74.1 ± 12.3 kg, and mean sports experience was 8.3 ± 2.1 years. Participants underwent pre- and post-fatigue assessments of concentric and eccentric hamstring peak torque, functional hamstring-to-quadriceps ratios, and AKE flexibility following a core endurance fatigue protocol. RESULTS:Following fatigue, eccentric hamstring strength and the functional hamstring-to-quadriceps ratio at 240°/s decreased significantly. The changes in the functional hamstring-to-quadriceps ratio at 60°/s and AKE flexibility were smaller and not consistently significant after adjustment. CONCLUSION:Core endurance fatigue is associated with acute neuromuscular changes in variables linked to hamstring function. These exploratory findings suggest that core endurance may be relevant in injury prevention, although prospective studies are needed to establish clinical relevance.

IntroductionThe aim of the study was to compare the effects of single-task versus dual-task training on dual-task walking performance, prosthetic-limb kinematics, centre-of-pressure behaviour, and health-related quality of life in adults with transtibial amputation.MethodsForty-five participants undertook an eight-week intervention and were randomly allocated to one of three groups: control, single-task training, or dual-task training. Gait variables were obtained from 3D motion capture and force-plate analysis, while health-related quality of life was assessed using a composite measure derived from the WHOQOL-BREF.ResultsTwo-way mixed ANOVA showed that both single-task and dual-task training produced significant improvements in dual-task walk-performance time compared with the control group (p < 0.0001). Positive training effects were also observed for prosthetic-limb step length (p < 0.001), knee and hip joint range of motion (p < 0.05), and anterior-posterior (p < 0.001) and mediolateral (p < 0.01) centre-of-pressure displacement, with dual-task training producing greater improvements than single-task training across all gait variables. Only dual-task training resulted in significant pre- to post-intervention improvements in participants quality of life (p < 0.0001).DiscussionThese findings indicate that an eight-week programme of single- or dual-task training improves walking capability in individuals with transtibial amputation, reflective in improved gait automaticity and more stable, efficient centre-of-pressure transitions from foot strike to push-off in the affected limb. Dual-task training provides additional benefit, producing greater gains across all gait variables and resulting in a significant improvement in perceived quality of life. Future research should examine the long-term transfer of cognitive-motor training to real-world mobility and participation outcomes.

As the aging process progresses, the mass and strength of skeletal muscles gradually diminish, which subsequently affects functional performance. Age-related disturbances in the neuromuscular junction (NMJ) structure and elevated levels of C-terminal Agrin Fragment (CAF) lead to reduced innervation capacity and muscle loss. Physical inactivity among older adults often exacerbates muscle wasting and weakness. This study aimed to assess the effects of suspension training on body composition, physical performance, and CAF levels in older adults. Thirty healthy older adults (17 females and 13 males; mean age: 67.91 ± 4.50 years) were randomly divided into suspension (n = 17) and control (n = 13) groups. Training sessions were held three times per week at moderate intensity over 8-weeks, including pre-and post-assessment. While body mass index, fat mass, and lean body mass did not show significant changes, there were noticeable improvements in isometric knee-extension strength for the right (P < 0.01) and left (P < 0.05) legs, balance (P < 0.05), flexibility (P < 0.01), 30-sit-to-stand (P < 0.01), and Timed Up and Go (P < 0.05) performances following the exercise intervention. However, suspension training did not result in a significant effect on CAF concentration. Despite the absence of a reduction in CAF levels, the observed functional gains highlight suspension training as a promising exercise modality for enhancing physical performance, supporting independence, and potentially counteracting the effects of sarcopenia in older individuals.

CONTEXT:Chronic ankle instability (CAI) is a common consequence of a lateral ankle sprain. Sex differences in functional outcomes exist, but there is a lack of female-specific intervention studies. Hop stabilization training is effective in male athletes with CAI but has not been investigated in female athletes. Therefore, the purpose of this investigation was to describe the effect of hop stabilization exercises on functional movement patterns and patient-reported outcomes in female athletes with CAI. We also compared the current effect sizes with those observed in an all-male cohort following an identical intervention. DESIGN:Randomized controlled trial. METHODS:Fourteen female CAI participants completed hop stabilization training (age = 25.29 [5.86] y), and 14 female CAI participants were in the control group (age = 24.73 [6.97] y). Inclusion criteria were consistent with the International Ankle Consortium recommendations. The hop stabilization program consisted of three 20-minute sessions per week for 6 weeks. Sessions consisted of increasing foot-to-ground contacts each week until a taper in the final week. Exercise difficulty was also modified throughout the program. Functional movement patterns via the Functional Movement Screen and Fusionetics Scores, dorsiflexion range of motion, and select region-specific patient-reported outcomes were captured. RESULTS:The hop training group (pre: 12.68 [1.32] cm, post: 13.42 [1.35] cm) had a significant improvement (P< .001) in dorsiflexion range of motion relative to the control group (pre: 13.62 [1.22] cm, post: 13.68 [1.16] cm). Hop training also significantly improved (P,<0.01) functional movement patterns and all patient-reported outcomes. Relative to an all-male cohort who previously underwent the same hop stabilization program, the current female cohort demonstrated larger effect sizes, but all 95% CIs overlapped. CONCLUSIONS:A 6-week hop training program significantly improves patient-reported outcomes, dorsiflexion range of motion, and functional movement patterns in female athletes with CAI .

Extended periods of inactivity in sports can impact athletes’ performance and overall well-being. The current study examined the effects of a 10-week wrestling -specific detraining period on the isokinetic strength of knee and shoulder flexor and extensor muscles, knee proprioception, and dynamic balance among young male elite wrestlers. This prospective study included 63 male wrestlers : age (19.33 ± 3 years), height (174.32 ± 6.8 cm), weight (80.21 ± 22.01 kg), BMI (25.34 ± 5.89), fat percentage (13.25 ± 5.80) in Tehran’s premier wrestling league. Baseline measurements, including isokinetic strength of knee and shoulder flexors and extensors, knee proprioception, and dynamic balance, were evaluated using the Biodex 4 dynamometer and Biodex balance meter, respectively, and repeated after a 10-week lockdown during the COVID-19 pandemic at Shahid Beheshti University, Tehran, Iran. Statistical analysis utilized dependent t-tests to compare the results. Significant differences were observed in the isokinetic strength of shoulder and knee flexor and extensor muscles at angular speeds of 60, 180, and 300 degrees per second after 10 weeks of detraining (p < 0.05). Additionally, a decrease in the accuracy of knee joint proprioception was found, including active angle restoration at angles of 30°, 60°, and 90° and passive movement detection in flexion and extension at a 90-degree angle (p < 0.05). Moreover, dynamic balance significantly reduced in the single-leg form (p < 0.05). The findings revealed that wrestling -specific detraining period can significantly affect musculoskeletal and proprioceptive parameters in wrestlers, increasing the risk of injuries and reducing the performance and physical fitness. Consistent engagement in wrestling -specific training is essential to ensure optimal fitness and overall well-being, particularly for elite athletes.

Purpose The presence of spinal arches is crucial for maintaining good body posture, reducing pressure on joints, and preventing deformities caused by misalignment. Engaging in exercises that focus on correcting body alignment, such as walking backward, can enhance posture and various related factors. Method A group of 46 female students suffering from forward head posture was selected (age: 22.89 ± 2.31 years, height: 1.63 ± 0.05 m, weight: 60.01 ± 5.41 kg, body mass index: 22.38 ± 1.28 kg/m2) and randomly divided into two groups. The intervention group participated in three exercise sessions per week for four weeks, while the control group did not receive any intervention during the study. Changes in the craniovertebral angle, proprioception, resistance, and foot pressure were measured using photogrammetry, head-neck angle examination with a laser pointer, a balance measuring device, and a foot scanner. Findings The results of this study showed that the training program had a significant effect on the craniovertebral angle (P = 0.001), neck proprioception (P = 0.001), balance (P = 0.001), and sole pressure (P = 0.001). Likewise, the results of the group comparison revealed significant differences in various variables, such as the craniovertebral angle (P = 0.001), neck proprioception (P = 0.001), balance (P = 0.001), and plantar pressure (P ≥ 0.05). Conclusion This study demonstrated that walking backward enhanced the craniovertebral angle, proprioception, balance, and alterations in the plantar center of pressure. Therefore, this exercise is recommended as a complementary therapeutic approach for individuals with forward head posture.

Background: Myofascial pain syndrome (MPS) is caused by sensitive spot in muscles that are known as trigger points (TPs) which can have complications that can affect person's quality of life. Massage and self-myofascial-release (SMR) are two non-invasive techniques which are used to reduce the side effects of TPs. Aim: The present study is intending to compare the effect of the two mentioned techniques in reducing complications caused by TPs such as reduced ROM and pain in women with MPS of the trapezius muscle. Materials and Methods: 45 women aged 20-25 years with active TPs in the trapezius muscle were randomly divided into two experimental groups and one control group. The research process was one week which consists of pretest, 5 days intervention and post-test. The variables included pain measured by OBER questionnaire and ROM of neck measured by goniometer. Results: The results of the study showed that massage can have a significant effect on the ROM of neck including neck flexion (P= 0.00), extension (P= 0.00), left (P= 0.00) and right (P= 0.004) lateral flexion and left (P=0.00) and right (P= 0.04) rotation (P<0.05). Both massage and SMR interventions had a significant effect on reducing pain measured by OBER questionnaire (P<0.05). Conclusion: Findings of this study showed that myofascial release massage can have better effects on increasing neck ROM. Both treatment modalities are useful in reducing pain. Based on the obtained results, we recommend that specialists use massage intervention instead of myofascial self-release (SMR) for individuals suffering from MPS and neck pain, in order to achieve quicker and more extensive results.

Objective: This study aimed to investigate the effect of 4 weeks of continuous exercise combined with abdominal fat tissue massage on body composition in overweight individuals. Materials and Methods: Twenty-two participants (mean (±SD) age 28(±3) years; BMI 27.5 (±1.7)) were randomly divided into three groups: continuous training (CT, N= 7), continuous training with massage (CT+MA, N= 8), and massage only (MA, N= 7). The massage groups received 15-minute abdominal massages three times a week. The CT+MA group performed moderate continuous training at 50-60% VO2peak for 45 minutes after the massage. The CT group followed the same training protocol without massage. Body composition was assessed before and after the intervention, measuring fat percentage, waist to hip ratio (WHR), abdominal hip circumference, weight, and abdominal skinfold thickness. Results: The PBF, WHR, and skinfold thickness values in the abdominal area of the CT+MA group had a significant decrease compared to MA and CT groups. Conclusion: The results suggest that abdominal massage before exercise enhances lipolysis and spot fat reduction in the massage area, probably by increasing blood supply to subcutaneous fat tissue. This intervention could be a practical approach to boost lipolysis in future research.

Background:The menopause stage in women reduces estrogen levels and bone indicators. This study compared the effects of high-intensity resistance training (HIRT) and low-intensity resistance training (LIRT) on bone mineral density (BMD) and bone mineral content (BMC), T-score, and Z-score in postmenopausal women with osteopenia. Methods:A randomized controlled trial was conducted among 45 postmenopausal women, aged 50 to 60, who were randomly assigned into 3 parallel groups (n = 15 in each). The exercise program was performed by the interventional groups-the HIRT and LIRT groups-at 4 different intensities, 3 times a week for 24 weeks: 8 repetitions at 80% of 1 repetition maximum and 16 repetitions at 40% of 1 repetition maximum. The evaluated areas (BMD, BMC, T-score, and Z-score) included the lumbar spine (LS) and the femur neck (FN) using a DEXA machine. One-way analysis of covariance and Bonferroni's post hoc tests were used for data analysis. Results:The results indicated significant differences in BMD, BMC, T-scores, and Z-scores between the means of the LS and the FN in all groups. In addition, significant differences were revealed in the BMC of the LS, the BMD, T-scores (P < 0.001), Z-scores (P = 0.001), and in the BMC of the FN (P < 0.001), the BMD (P = 0.001), T-scores, and Z-scores (P < 0.001), respectively. In addition, the HIRT group's bone indices were considerably greater than those of the LIRT group (P < 0.00). Nonetheless, LIRT was significantly greater than that of the control group (P > 0.00). Conclusion:According to the current findings, HIRT seems to be the most effective training program compared with LIRT for bone indicators improvement in the femur neck and the lumbar spine among postmenopausal women with osteopenia.

Abstract Background Wrestling is considered one of the oldest sports in the world. There is a high rate of injuries in Wrestling. To prevent injuries, it is necessary to identify the risk factors. Despite the functional importance of strength in wrestling, few studies have investigated the relationship between isokinetic strength and the rate of injuries in the sport. Objectives The objective of the present study was to investigate the relationship between the isokinetic strength of elite wrestlers and the rate of injuries prospectively. Method A total of 72 young wrestlers with at least 2 years of experience in the Tehran Wrestling Premier League participated in this study. Before the start of the competition season, the isokinetic strength of flexor and extensor muscles of the knee and shoulder were measured at different velocities by an isokinetic dynamometer. The injuries and training hours of these wrestlers were then recorded for nine months. Results The study results showed no significant relationship between isokinetic strength of flexor and extensor muscles of the knee or shoulder at different angular speeds of 60, 180, and 300°/s. There was neither significant between the ratio of the strength flexor/extensor for knee and/or shoulder in young elite wrestlers with injuries. Conclusion Isokinetic strength of lower and upper limb muscles alone cannot predict wrestlers' injuries. Therefore, the use of these tests is not recommended to evaluate the risk of injury in this population.

Background Resistance training is now highly recommended for enhancing physical fitness in preadolescence. According to this critical period of development, choosing the safe and efficient types of training is important. Aims Comparing the effect of two types of suspension and unsuspension resistance training on physical fitness and body composition in prepubescent soccer athletes. Methods Thirty immature boys were assigned randomly to either total-body resistance exercise (TRX), bodyweight training (BW), and control groups. Training groups completed training programs for 8 weeks which designed progressively according to ACSM recommendations for children. Suspension training was conducted using TRX bands and unsuspension training using body weight. Results TRX training showed significant improvements in muscular endurance (p < 0.001), upper and lower body strength (both; p < 0.01), static balance (p < 0.05), and also percent body fat (p = 0.005) compared to BW training. Also, there were no difference in aerobic power, agility, and muscular power. Conclusions Although the benefits of both types of resistance training were evident, TRX training seems to be more effective in children's physical fitness components and can be developed as a fitness training method in youth athletes.

Purpose The aim of this study was to investigate the anthropometric characteristics of elite taekwondo players based on weight categories, and to determine if the length of the lower extremities might influence player’s success-level. A total of 59 elite male taekwondo players (22.02 ± 3.07 years) participated in this study. Methods All anthropometric assessments were performed according to the standards and methodology of the International Society for Advancement of Kinanthropometry. The 18 anthropometrical variables were measured for each athlete and compared between 7 different weight categories. The players were also divided into two groups (national and international) and the ratios of sitting-height to stature were compared. Results There were significant differences ( P < 0.05) between weight divisions in stature, body mass index, percentage of body fat, endomorphy, and mesomorphy, which were greater ( P < 0.05) in heavy weight groups than light weight groups, and ectomorphy, which was greater ( P < 0.05) in very light weight groups compared with the other weights. There was no significant difference in lean mass index ( P > 0.05) between weight groups. Sitting height/stature ratio was significantly different ( P < 0.05) between the two groups, where the international group had longer lower extremities than the national group. Conclusion The findings of this study provide a valuable framework to support talent identification programmes and the development of specialised preparatory strategies for different weight divisions with the sport.

Purpose: Muscle strength is needed to perform many movements and skills in football such as speed decreasing, shooting, dribbling, rotating, and jumping. Several studies shown that lower limb muscle strength can increase the quality of exercise skills. But, few studies have compared the strength of players at different levels. Therefore, the present study intends to investigate the strength of the isokinetic and isometric knee muscles of the elite, sub-elite and amateur football players of Iran. Methods: The isokinetic strength of the knee muscles in 102 soccer players including 29 players of the national under-23 football team of Iran (elite), 29 players of 1st division of under-23 football team of Iran (sub-elite) and 44 players of 2nd division of under-23 football team of Tehran province (amateur) was measured for angular momentum of 60 and 180 degrees per second by the isokinetic Biodex. The isometric strength of flexor and extensor muscles of knee were measured at an angle of 60 degree. Results: The results of the ANOVA test showed that elite player had superior strength of flexor and extensor knee muscles in both momentum angles of 60 and 180 degrees per second and flexor/ extensor isokinetic strength ratio at 180 degrees per second speed than sub-elite and amateur players significantly. However, there was no significant difference in the ratio of flexor/ extensor isokinetic strength ratio at 60 degrees per second. Conclusions: Considering the results of the present study, it can be concluded that competition level affect the isokinetic and isometric strength of the knee muscles of young football players of Iran.

Football is a contact sport with a significant risk of injury. Although proprioception is well studied in rehabilitation, little is known about the association between proprioception and the occurrence of sport injuries. The purpose of this study was to look into the association between ankle and knee proprioception and lower extremity injuries in young football players. Seventy-three football players from the highest U-21 league in Iran volunteered to participate in this study. Before the start of the 2017-2018 competitive season, joint position sense was measured at 30°, 60° and 90° knee flexion and at 10° and 15° ankle dorsiflexion, and inversion using the Biodex Isokinetic pro 4 system. The teams' medical staff recorded football-related lower extremity injuries. We used mixed effects Cox regression models to calculate hazard ratios (HRs) with 95% CIs, acknowledging the clustered data structure. Twenty-two players (30.1%) suffered one or more lower extremity injuries during the season. None of the proprioception measures examined was significantly associated with the risk of lower extremity injuries. Based on these results of our sample, joint position sense does not seem to be associated with lower extremity injuries in young male football players.

BACKGROUND:Validating any screening test to predict and prevent football injuries is in need of identifying related risk factors through prospective designs. In spite of the extensive use of strength testing in football players, there are limited studies investigating the relationship between isokinetic muscle strength and injury risk in young football players. The present study aimed to evaluate the relationship between isokinetic strength and the risk of lower extremity injury among Iranian young football players.METHOD:ology: seventy three U-21 football players participated in this study. Isokinetic strength of hip, knee and ankle muscles were measured using the Isokinetic system pro 4. Injuries and exposure in training and matches were registered prospectively by club medical staff for one season.RESULTS:Significant relationships were revealed between the isokinetic strength of hip abductor and adductor muscles, and isokinetic strength ratio of hip abductor/adductor muscles at an angular speed of 30°/sec, the isokinetic strength of hip abductor muscles at 90°/sec, and isokinetic strength of knee flexor and extensor muscles at 60°/sec and knee flexor/extensor strength ratio at angular velocities of 60°/sec with the injury occurrence among football players.CONCLUSION:lower extremity isokinetic strength indices are associated with injuries in young male football players.

Effect of Functional Strength Training on Gait Kinematics, Muscle Strength and Static Balance of Young Adults with Down Syndrome

The risk of injury in football is high. Many researchers have introduced muscle strength as one of the most important internal risk factors, but few studies have examined the relationship between the isometric strength of muscles and incidence of injuries. Therefore, the aim of this study was to examine the relationship between isometric strength of lower extremity muscles and the incidence of injuries in football players and the power to predict these injuries. The sample of this study included 73 football players under 21 years of age. Before the beginning of the season, the anthropometric dimensions and isometric strength of lower extremity in dominant leg of each player were measured by Isokinetic device (Biodex system 4), then each player was followed up for 8 months and their injuries were recorded. The results of Cox regression test showed no significant relationship between isometric strength of the measured muscles and the incidence of injuries in lower extremity. According to these results, it is suggested that medical and technical staff of football teams use isometric tests to identify high risk players. Other strength evaluation methods such as isokinetic and isotonic strengths may be more effective.

Purpose: The purpose of this study was to compare the effect of a fatigue protocol on some kinematic gait parameters in students with genu valgum, genu varum and normal people. Methods: Samples of this study included 37 high school students (age 16.39 years, height 172.42 cm, weight 71.10 kg) who participated voluntarily in the study and were divided into three groups of genu valgum (n=13), genu varum (n=12) and normal (n=12). In order to evaluate the alignment of the lower extremity, goniometry-based quadriceps angle (Q) measurement was performed and the kinematic parameters were evaluated by a 10-m walk test using KINOVEA software. Results: Intragroup comparison results showed that there were significant differences in stance time, swing time, step length, walking speed, number of steps and walking distance between all three groups after inducing the fatigue protocol (p<0.001), while intergroup comparison results showed significant differences between the three groups only in terms of stance time, swing time, and stride length after applying the fatigue protocol (P<0.001). Conclusion: The present study showed that the fatigue protocol can affect kinematic gait parameters in people with knee abnormalities and those with normal alignment, and these effects differ in some parameters between normal subjects and those with genu varum and genu valgum.

AimsExisting evidence emphasize the role of mitochondrial dysfunction in sarcopenia which is revealed as loss of skeletal muscle mass and neuromuscular junction remodeling. We assessed the effect of low-intensity aerobic training along with blood flow restriction on muscle hypertrophy index, muscle-specific kinase (MuSK), a pivotal protein of the neuromuscular junction and Peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-1α) in aged male rats.Main methodsAnimals groups were control (CTL), sham (Sh), leg blood flow restriction (BFR), exercise (Ex), sham + exercise (Sh + Ex), and BFR plus exercise (BFR + Ex) groups. The exercise groups were trained with low intensity exercise for 10 weeks. 48 h after the last training session, animals were sacrificed under anesthesia. Soleus and EDL muscles were isolated, hypertrophy index was estimated and MuSK and PGC-1α were measured by western blot method.Key findingsHypertrophy index enhanced in soleus and Extensor digitorum longus (EDL) muscles of BFR + Ex group (P < 0.01 versus CTL and Sh groups, and P < 0.001 versus other groups). The MuSK protein of soleus and EDL muscles increased in BFR + Ex group (P < 0.01 and P < 0.001, respectively) in comparison with CTL and Sh groups. In BFR + Ex group, the PGC-1α protein increased in both soleus and EDL (P < 0.001 compared to other groups). Also the PGC-1α of soleus muscle was higher in Ex and Sh + Ex groups versus CTL and Sh groups (P < 0.05).SignificanceFindings suggest that low endurance exercise plus BFR improves the MuSK and hypertrophy index of both slow and fast muscles of elderly rats probably through the rise of PGC-1α expression.