Identifying and prioritizing selection indicators for elite women's badminton singles players: An analytic hierarchy process approach based on Delphi findings

To report the prevalence of hip pain in elite badminton players, describe their hip pathologies, and evaluate expectations regarding hip pain. All badminton players registered at the national sports institute (Institut national du sport, de l'expertise et de la performance; INSEP) in France on 01/09/2023 were contacted by the medical team to complete a questionnaire comprising training information, prevalence of hip pain, and expectations regarding hip pain. The medical database was reviewed to identify all hip pathologies recorded. Of the 20 elite badminton players registered at the national sports institute (10 females and 10 males, aged 23.8±3.9 years), 9 (45%) reported experiencing hip pain while registered at the institute, 4 at their dominant side only and 5 bilaterally. Six players had cam-type femoroacetabular impingement (FAI), concomitant with coxofemoral chondropathy and/or muscle tears in 3 athletes (requiring femoroplasty in 3). Furthermore, 3 more players had coxofemoral chondropathy and/or muscle tears. Before playing badminton at a high-level, 12 (60%) thought that becoming elite players could cause joint pain; however, none (0%) thought that it would cause pain specifically at their hip joint. Nine of 20 elite badminton players have experienced hip pain while registered at a national sports institute, with the most common hip pathologies being cam-type FAI (n=6; 30%) and muscle tears (n=4; 20%). Although before playing badminton at a high-level, none of the athletes thought that becoming an elite badminton player could cause pain specifically at the hip joint, at the time of the questionnaire, 19 athletes (95%) thought this was common. These findings could allow coaches and medical staff to align expectations regarding the likelihood of hip pain and hip pathologies in badminton players training at an elite level, by adjusting training regimens or implementing early screening.

PurposePeople vary in flexibility regarding maximum joint angle, resistance to stretch and mechanical responses during stretching exercises. Body composition (BC) has been been mentioned as one of the factors for flexibility differences. The aim of this study was to determine how body composition and anthropometric measures of the lower limb is associated with passive knee extension (PKE) torque-angle (T-A) response.MethodsTwenty-five male subjects with poor flexibility performed a maximal PKE repetition (velocity of 2°/s; 90 seconds in the static phase). Knee passive T-A, vastus medialis and semitendinosous electromyographic activity were recorded during the protocol. Viscoelastic stress relaxation (VSR) amplitude, knee passive stiffness (KPS), lower limb body composition assessed by dual energy x-ray absorptiometry, and anthropometry measures were determined.ResultsThigh skeletal muscle and bone mass, as well as thigh perimeter, showed a moderated correlation with passive torque (r = 0.45; r = 0.6; r = 0.59, respectively), joint angle (r = 0.46; r = 0.5; r = 0.5), and VSR (r = 0.46; r = 0.49; r = 0.5). Thigh skeletal muscle was also correlated with KPS (r = 0.42). All these correlations were statistically significant (p < 0.05).ConclusionsPassive knee extension T-A was found to be moderately correlated with lower limb BC. In particular, thigh perimeter and skeletal muscle mass were associated with knee passive stiffness and viscoelastic stress relaxation. More research is needed to understand what influences joint maximum angle, resistance to stretch and mechanical response to stretching.

Badminton is a fast-paced sport that requires a high level of skill. Despite its non-contact nature, badminton can still result in injuries. This review aimed to identify the characteristics of musculoskeletal injuries in elite badminton players. A systematic search was conducted through the electronic bibliographic databases between 2013 and 2025. The study followed the PRISMA guidelines, registered in PROSPERO, and article quality assessment was conducted using the Newcastle Ottawa Scale. A total of 11 eligible articles were included. Over 45% of elite badminton players have been injured in the past year. The most common location of injuries was at the lower extremity (54–71%), followed by the upper extremity (30–46%); tendinopathy (6–70%) and sprain (10–32%) are the most common types of injury. Identifying the characteristics of injuries in elite badminton players can provide valuable insights for healthcare professionals to develop effective injury prevention strategies for athletes.

Sarcopenia is an age-related degenerative loss of muscle mass and muscular function. Other than classification criteria from the European Working Group on Sarcopenia in Older People (EWGSOP) and Asian Working Group for Sarcopenia (AWGS), such as skeletal muscle index (SMI), handgrips strength (HGS), and 6-m normal walking speed (NWS), many other sarcopenic-related parameters have also been studied in the literature. PURPOSE: To discriminate classification of sarcopenia using related sarcopenic parameters. METHODS: This was a cross-sectional investigation. Subjects were above the age of 65 in Taoyuan, Taiwan. Measurement data of SMI, HGS, 6-m NWS, thigh circumferences and calf circumferences, muscular strength in knee extension and flexion, 30-s and 5 times sit-to-stand, and 8-inch timed-up-and-go were collected. Discriminant analysis was employed to detect related parameters that differentiated classification of sarcopenia using EWGSOP criteria. Significant level was at α = .05. RESULTS: A total 384 cases were included with averaged age of 71.2 ± 5.4 (male: N=135; female: N=249). Using the EWGSOP criteria, the prevalence of pre-sarcopenia and sarcopenia were 35.42% and 22.66% respectively. SMI and HGS contributed commonly to discriminate sarcopenia classification in male, female, and all subjects, but not 6-m NWS in male (p= .331). However, additionally, thigh circumference, calf circumference, and 8-inch timed-up-and-go could discriminate classification of sarcopenia for all subjects with correct prediction rate of 95.6% for male and 92.0% for female subjects. CONCLUSIONS: In addition to SMI and HGS, a brief thigh and calf circumference measurements in anthropometry, and the 8-inch timed-up-and-go in physical performance may seem appropriate in promotion of sarcopenia prevention for older adults in the community in Taiwan. Supported by Chang Gung Memorial Hospital Grant CORPG3G0022.

Lower extremity injuries are common in sport. Anterior cruciate ligament (ACL) injuries often result in muscle atrophy in the thigh and calf muscles of the injured leg. Evaluating muscle atrophy via circumferences to document asymmetry has been recommended and is often used clinically (1). Previous studies have shown a small loss of skeletal muscle mass (SMM) may cause a greater loss in muscular strength (1), thus investigating muscle mass and girth may be beneficial in evaluating return to play post-ACL injury. PURPOSE: The purpose of this study was to examine SMM and circumference discrepancies between injured and uninjured limbs post- ACL reconstruction. METHODS: Participants (n = 7, 4 F, 3 M; 21.9 ± 4.3 y; 5.24 ± 4.74 y post injury) were tested using bioelectrical impedance analysis (BIA). Fat mass, fat-free mass, body fat percentage, and SMM (kg) for extremities and torso were obtained. Circumference measurements were taken on the injured (I) and un-injured (NI) limbs at the mid-patella, and superiorly and inferiorly of the patellar poles at 10, 15, and 20 centimeters, using a standard, non-elastic tape measure. RESULTS: There was no significant difference between SMM (I :14.54 ± 3.80 kg; NI:14.48 ± 3.48 kg; t(6) = 0.46, p = .660). Roughly half of participants had greater SMM in the injured leg versus un-injured leg. There were no significant differences in circumference measurements between the limbs. CONCLUSIONS: There was evidence of decreased SMM in some participants following ACL injury. It is possible that continued study with more participants may find difference in muscle mass following injury. SMM and circumferences provide useful information concerning muscular atrophy and discrepancies between limbs. SMM obtained via BIA may be utilized as a cost-effective measure indicative of knee stability and limb strength for return to play protocol (1). Future research should include measurements made pre and post injury/surgery to understand muscle mass progression following injury. 1-Ross, C. M., & Worrell, T. W. (1998). Thigh and calf girth following knee injury and surgery. Journal of Orthopaedic & Sports Physical Therapy, 27(1), 9-15.

Background Assessment of cardiorespiratory fitness (CRF) is a standard procedure in routine clinical practices. Early identification of risk factors through screening is vital in the fight against chronic diseases. Evaluation of CRF can impose cost implications in the clinical setting; thus, a simple and easy-to-use test is to be advocated. The Ruffier test is a simple test that can assess CRF, and it is necessary to find whether the test reflects the effects of compounding factors in CRF. Objective This study aims to determine the association between CRF (estimated VO2max) with cardiovascular, anthropometric, and physical risk factors using the Ruffier test. Methods A cross-sectional study with a sample of 52 male participants was conducted. Before the Ruffier test, each participant's body weight, height, waist circumference, skinfold thickness, thigh length, lower-limb length, thigh circumference, physical activity, blood pressure, smoking, diabetes, and pulmonary functions were recorded, and these factors correlated with CRF. Results There was a significant inverse relationship found between the estimated VO2max and age, height, body weight, body mass index, waist circumference, a sum of skinfold, fat percentage, thigh length, lower-limb length, thigh circumference, smoking, blood pressure, heart rates, and diabetes (p < 0.05). A significant positive correlation was found between the estimated VO2max with physical activity and respiratory functions (p < 0.05). In the multivariable model, body weight and resting heart rate were significantly inversely associated with the estimated VO2max(p < 0.05). Conclusion Using the Ruffier test, various risk factors of CRF are correlated with the estimated VO2max. This test reflects the effects of different compounding factors on CRF; therefore, it can be used in routine clinical practices to identify the risk factors early.

The influence of resistance exercise training prescription variables on skeletal muscle mass, strength, and physical function in healthy adults: An umbrella review

The ability to accurately project (e.g. throw, kick, hit) an object at high speed is a uniquely human skill, and this ability has become a critical feature of many competitive sports. Nonetheless, in some sports, the target or end-point for a projected object is often not reached because an opponent intercepts or returns the object; thus, a player cannot use object landing location information to inform accuracy outcome. By comparing the landing location of serves performed without an opponent by elite badminton players to predicted landing points of serves delivered with an opponent, we aimed to determine whether object projection accuracy is affected by the presence of an opponent. Landing locations of serves to an opponent were predicted using a model developed through analysis of serves without an opponent present. The model predicted that 69% of serves to an opponent would have landed on or short (i.e. outside the permitted area) of the service line. Thus, serve trajectory in elite badminton players was considerably altered by the presence of an opponent, despite their aim to serve to a specific point on the court.

Background: Mammographic density (MD) of the breast and body mass index (BMI) are positively associated with the risk of breast cancer in postmenopausal women, but they are inversely associated with each other. We supposed that the reason for this paradox may be due to the heterogeneity of BMI. Therefore, we calculated the skeletal muscle mass index (SMI), and evaluated whether SMI was an independent predictor for MD. Methods: A cross-sectional study was performed in 143,456 women who underwent comprehensive examinations from 2012 to 2016. Mammographic density was assessed using Breast Imaging Reporting and Data System, and the breasts were classified as dense or non-dense. The association between SMI, anthropometric factors, and MD were estimated using logistic regression models after adjustment for potential confounders. Results: In all, 115,013 premenopausal women (80.2%) and 28,443 postmenopausal women (19.8%) were included in the analysis. In both pre and postmenopausal women, weight, BMI, SMI and waist circumference were associated with MD. After adjustment for confounding factors including BMI, the odds ratios (ORs) for MD with 95% confidence interval for the dense breasts was between the highest and lowest quartiles of SMI at 2.65 (2.52–2.79) for premenopausal women and at 2.39 (2.02–2.82) for postmenopausal women. Conclusions: SMI was related to MD independent of BMI, which could be due to the similar growth mechanism of the skeletal muscle and breast parenchymal tissue. The positive correlation between the muscularity and breast density might explain the reason for the paradoxical relationship between BMI, MD and breast cancer risk in previous studies. Table 1. Characteristics and anthropometric measurements of participants by menopausal status and mammographic densityVariablesAll subjects (n=143 456)Premenopausal womenPostmenopausal womenNon-dense breast (n=60 180)Dense breast (n=54 833)p valueNon-dense breast (n=25 570)Dense breast (n=2873)p valueAge (years)143 45639.3 ± 5.737.3 ± 5.2&amp;lt;0.00158.0 ± 7.550.7 ± 8.2&amp;lt;0.001Height (cm)143 456160.7 ± 5.1161.0 ± 5.0&amp;lt;0.001156.2 ± 5.3158.0 ± 5.2&amp;lt;0.001Weight (kg)143 45658.4 ± 8.853.9 ± 6.9&amp;lt;0.00157.9 ± 8.054.4 ± 7.6&amp;lt;0.001Body mass index (kg/m2)143 45622.6 ± 3.220.8 ± 2.5&amp;lt;0.00123.7 ± 3.121.8 ± 2.9&amp;lt;0.001Age at menarche (years)139 54513.8 ± 1.513.8 ± 1.5&amp;lt;0.00115.4 ± 1.814.8 ± 1.7&amp;lt;0.001Waist circumference143 45677.7 ± 8.273.0 ± 7.0&amp;lt;0.00181.5 ± 8.475.6 ± 8.2&amp;lt;0.001Skeletal mass index143 45637.2 ± 3.139.2 ± 3.0&amp;lt;0.00135.7 ± 3.238.1 ± 3.3&amp;lt;0.001Calcium level adjusted to albumin (mmol/L)140 2788.8 ± 0.38.8 ± 0.3&amp;lt;0.0019.0 ± 0.39.0 ± 0.3&amp;lt;0.001Parous135 92586.680.0&amp;lt;0.00197.793.3&amp;lt;0.001History of estrogen replacement therapy143 4561.11.10.1494.67.0&amp;lt;0.001Data are presented as mean ± standard deviation or %. Table 2. Multivariate analysis for the association of higher mammographic density with skeletal mass index after further adjustment for BMIPremenopausal womenPostmenopausal womenMultivariate (+BMI) ORa (95% CI)p valueMultivariate (+BMI) ORa (95% CI)p valueSkeletal mass indexQ1 (&amp;lt; 35.5)RefRefQ2 (35.5–37.8)1.26 (1.21 to 1.32)&amp;lt;0.0011.16 (1.01 to 1.33)0.034Q3 (37.8–40.1)1.63 (1.55 to 1.70)&amp;lt;0.0011.55 (1.33 to 1.80)&amp;lt;0.001Q4 (&amp;gt; 40.1)2.65 (2.52 to 2.79)&amp;lt;0.0012.39 (2.02 to 2.82)&amp;lt;0.001aORs and 95% confidence interval (95% CI) from the multivariate model including age, BMI and variables (age at menarche, parous, history of estrogen replacement therapy, calcium level adjusted to albumin. Citation Format: KwanHo Lee, HyeWon Bang, SeungHye Choi. Association between skeletal muscle mass and mammographic breast density [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-08-30.

This study investigated the physiological and anthropometric characteristics of elite women rugby league players and developed physical performance standards for these athletes. Thirty-two elite women rugby league players underwent measurements of standard anthropometry (body mass, height, sum of 7 skinfolds), muscular power (vertical jump), speed (10-, 20-, and 40-m sprint), agility (505 test), glycolytic capacity (glycolytic agility test), and estimated maximal aerobic power (multistage fitness test). The skinfold thickness, speed, agility, vertical jump height, glycolytic capacity, and estimated maximal aerobic power results were 6.0-38.1% poorer than previously reported for elite women team sport athletes (e.g., rugby union, soccer, and hockey). Although no significant differences (p > 0.05) were detected between selected and nonselected players for any of the physiological or anthropometric characteristics, significant differences (p < 0.05) were detected between forwards and backs for body mass, skinfold thickness, 10-, 20-, and 40-m speed, and estimated maximal aerobic power. When data were analyzed according to positional similarities, it was found that the hit-up forwards positional group were heavier, had greater skinfold thickness, and had lower 10-, 20-, and 40-m speed, muscular power, glycolytic capacity, and estimated maximal aerobic power than the adjustables and outside backs positional groups. The results of this study show that elite women rugby league players have slower speed and agility, lower muscular power, glycolytic capacity, and estimated maximal aerobic power, and greater body mass and skinfold thickness than previously reported for other elite women team sport athletes. These findings show the need to develop all physiological parameters to allow elite women rugby league players to more effectively tolerate the physiological demands of competition, reduce fatigue-related errors in skill execution, and decrease the risk of injury.

Skeletal muscle mass is essential for mobility, physical performance, and disease prevention, serving as a predictor of morbidity and mortality, particularly in sarcopenia. Muscle mass decreases with age and is associated with adverse clinical outcomes. Accurate assessment is crucial in clinical practice but presents challenges. Imaging methods like MRI, DXA, computed tomography (CT), ultrasound, and other techniques like bioelectrical impedance analysis (BIA) are effective but have limitations such as cost, accessibility, and operator dependency. Anthropometric measures - such as calf circumference, mid-upper arm circumference (MUAC), forearm, and thigh circumference - are simple, low-cost alternatives that correlate well with muscle mass, though they can be influenced by factors like age, sex, and body fat. Adjusted measures using skinfold thickness improve accuracy but are less reliable in older adults. Prediction equations based on anthropometry can estimate total muscle mass but must be validated for specific populations. In complex cases like obesity or malnutrition, equations that incorporate biochemical markers or dynamometry may enhance precision. Overall, selecting the appropriate muscle mass assessment method requires consideration of population characteristics, available resources, and proper professional training to ensure accurate and clinically useful results.

Although accumulating evidence has shown that there is a U-shaped association between sleep duration and the risk of metabolic disorders related to obesity, its underlying mechanism is still not fully understood. In this study, we analyzed the association of sleep duration with metabolic, anthropometric, and lifestyle factors in patients with type 2 diabetes. Subjects were 280 patients with type 2 diabetes aged 60±14 years with BMI 25.9±5.1kg/m2, and A1C 9.0±1.8%. Patients with advanced complications were excluded from the study. Diets were evaluated by registered dietitians using software. Body composition was assessed by the multi-frequency bioelectrical impedance method. Habitual physical activity included all of leisure-time, occupational, and household ones. Self-reported nightly sleep duration was 6.4±1.4 h with no gender difference. Sleep duration was inversely correlated with A1C levels, total energy intake, and the intake of three major nutrients. Body fat ratio and skeletal muscle mass, but not body weight or BMI, were correlated positively and negatively, respectively, with sleep duration, even after the adjustment for age. When subjects were divided into three groups based on sleep duration, the intake of fat and carbs was highest in short sleepers (&amp;lt;5.5 h). The percentage of patients who had habitual physical activity was lower in long sleepers (&amp;gt;7 h) than in moderate or short sleepers (25.4%, 31.3%, and 44.0%, respectively). Thus, short sleepers ingested more energy, but %body fat was lower than other groups. This apparent paradox can be explained by the high ratio of habitual physical activity in short sleepers. Long sleep duration is likely a marker of low physical capacity in diabetic subjects. Hence, the U-shaped association may be attributable, at least in part, to excessive eating in short sleepers and a sedentary lifestyle in long sleepers. Disclosure H. Nakayama: None. Y. Yamada: None. K. Yamada: None. S. Iwata: None. N. Wada: None. Y. Tajiri: None. M. Nomura: None.

Scissor-kick jumps are frequently employed by elite badminton players when performing forehand jump strokes from the rear court forehand side. The joint loads experienced during the landing phase may contribute to the high number of lower limb injuries, yet our understanding of these loads is limited. This exploratory study comprehensively evaluates the lower limb joint mechanics during scissor-kick jump landings in elite male badminton players. Ten Danish national male players performed three variations of the scissor-kick jump in a biomechanical laboratory: submaximal jumps from a static position, maximal jumps from a static position, and jumps with game-like backward chassé steps. We recorded the landing 3-dimensional joint kinematics and kinetics of the racket-leg using a 10-camera motion capture system and a force platform. Our analysis using statistical parametric mapping one-way repeated measures ANOVA revealed no significant differences in the hip, knee, and ankle joint angles, moments, and power waveforms during the landing phase across the three jump variations. Indicating that elite male badminton players landing mechanics are not altered by increased jump height or the inclusion of preceding game-like footwork. We observed that the triceps surae muscles absorb 41% of the total eccentric joint work during the landing phase, indicating their crucial role in managing landing impacts. Additionally, the initial landing phase is characterized by high external knee and hip extensor and adductor moments. These findings highlight the importance of incorporating exercises targeting the triceps surae muscles and Achilles tendons in badminton-specific training programs to prepare players for the high eccentric loads during scissor-kick jump landings. The high hip, knee and ankle joint loads identified in this study may contribute to the high incidence of lower limb injuries in elite badminton.

BackgroundThe negative effects of dehydration on aerobic activities are well established. However, it is unknown how dehydration affects intermittent sports performance. The purpose of this study was to identify the level of dehydration in elite badminton players and its relation to muscle strength and power production.MethodologySeventy matches from the National Spanish badminton championship were analyzed (46 men’s singles and 24 women’s singles). Before and after each match, jump height and power production were determined during a countermovement jump on a force platform. Participants’ body weight and a urine sample were also obtained before and after each match. The amount of liquid that the players drank during the match was also calculated by weighing their individual drinking bottles.Results and DiscussionSweat rate during the game was 1.14±0.46 l/h in men and 1.02±0.64 l/h in women. The players rehydrated at a rate of 1.10±0.55 l/h and 1.01±0.44 l/h in the male and female groups respectively. Thus, the dehydration attained during the game was only 0.37±0.50% in men and 0.32±0.83% in women. No differences were found in any of the parameters analyzed during the vertical jump (men: from 31.82±5.29 to 32.90±4.49 W/kg; p>0.05, women: from 26.36±4.73 to 27.25±4.44 W/kg; p>0.05). Post-exercise urine samples revealed proteinuria (60.9% of cases in men and 66.7% in women), leukocyturia (men = 43.5% and women = 50.0%) and erythrocyturia (men = 50.0% and women = 21.7%).ConclusionsDespite a moderate sweat rate, badminton players adequately hydrated during a game and thus the dehydration attained was low. The badminton match did not cause muscle fatigue but it significantly increased the prevalence of proteinuria, leukocyturia and erythrocyturia.

Infections following renal transplantation: Chronology, co-morbidities and effect on graft function – Western India experience