Use of Dual-Task Timed-Up-and-Go Tests for Predicting Falls in Physically Active, Community-Dwelling Older Adults-A Prospective Study.

This prospective study aimed to determine which specific mobility tests were the most accurate for predicting falls in physically active older adults living in the community. Seventy-nine physically active older adults who met the American College of Sports Medicine physical activity guidelines volunteered. Participants were assessed and followed up for 12 months. Mobility assessments included the 30-s sit-to-stand test, five times sit-to-stand test, single-task timed-up-and-go test (TUG), motor dual-task TUG (Mot-TUG), and cognitive dual-task TUG (Cog-TUG). Mot-TUG and Cog-TUG performances were moderately correlated with number of falls (r = .359, p < .01 and r = .372, p < .01, respectively). When Mot-TUG, Cog-TUG, or Age were included as fall predictors, discrimination scores represented by the area under the receiver operating characteristic curve (AUC) were AUC (Mot-TUG) = 0.843 (p < .01), AUC (Cog-TUG) = 0.856 (p < .01), and AUC (Age) = 0.734 (p < .05). The cutoff point for Cog-TUG was 10.98 s, with test sensitivity of 1.00 and specificity of 0.66. Fall predictors for different populations may be based on different test methods. Here, the dual-task TUG test more accurately predicted falls in older adults who met American College of Sports Medicine's physical activity guidelines.

Ankle complex proprioception and plantar cutaneous sensation in older women with different physical activity levels.

Ankle complex proprioception and plantar sole sensitivity have been separately reported to be essential sensory components in balance control among the elderly. However, their inter-relationship is still unknown. Further, although optimal proprioceptive ability has been related to regular physical exercise, the association between physical activity (PA) levels, ankle proprioceptive acuity and plantar cutaneous sensation is unclear. Therefore, this study aims to compare ankle proprioceptive acuity and plantar cutaneous sensitivity scores between groups of older women with different PA levels, and to determine any relationships between plantar sole cutaneous sensitivity, ankle proprioceptive performance and PA levels. 68 older female participants were recruited who were distributed over three PA levels: highly active, moderately active, and inactive. PA level was assessed by the International Physical Activity Questionnaire. Ankle proprioceptive acuity was tested in full weight-bearing stance using the ankle Active Movement Extent Discrimination Apparatus (AMEDA) and plantar cutaneous sensitivity was assessed with the Nylon Semmes-Weinstein monofilaments test. Results showed that ankle proprioceptive acuity scores were strongly positively related to plantar sole sensitivity scores (r = 0.80, p < 0.001; effect size: η2 = 0.715), and both scores correlated with PA level. In conclusion, plantar cutaneous sensitivity and ankle complex proprioception were strongly correlated in older females with different levels of physical activity, suggesting that the former may be an integral part of the latter. Given the previously reported contribution of AMEDA ankle proprioceptive acuity to sport performance level, the health of the plantar sole of the foot may be important as a performance determinant.

Can Therapeutic Exercises Improve Proprioception in Chronic Ankle Instability? A Systematic Review and Network Meta-analysis.

OBJECTIVE: To assess exercise therapies that aim to enhance proprioception in individuals with chronic ankle instability (CAI). DATA SOURCES: Five databases (PubMed, Embase, Cochrane Library, Web of Science, and EBSCO) were searched in October 2021. STUDY SELECTION: Randomized controlled trials involving exercise therapy conducted on individuals with CAI were included. DATA EXTRACTION: Data were extracted by 2 independent reviewers using a standardized form. Methodological quality and risk of bias were assessed with the Physiotherapy Evidence Database scale. DATA SYNTHESIS: The end trial weighted mean difference and standard deviations were analyzed, and the synthetic value for the improvement in error scores of ankle joint position sense in multiple directions was evaluated. RESULTS: Eleven trials with 333 participants were eligible for inclusion in this systematic review and were included in the network meta-analysis. Foot and ankle muscle strengthening exercise showed the highest probability of being among the best treatments (surface under the cumulative ranking [SUCRA]=74.6%). The next 2 were static balance exercise only (SUCRA=67.9%) and corrective exercise (SUCRA=56.1%). The SUCRA values of proprioceptive exercise, dynamic balance exercise only, aquatic exercise, rehabilitation exercise with brace, mixed static/dynamic balance exercise, and control were at relatively low levels and scored at 49.6%, 48.8%, 47.8%, 47.7%, 44.0%, and 13.5%, respectively. CONCLUSIONS: Foot and ankle muscle strengthening exercise may have a good effect when used to improve joint position sense in individuals with CAI. The more complex balance exercise intervention becomes, the less effective the proprioceptive outcome.

Ankle Proprioception in Male and Female Surfers and the Implications of Motor Experience and Lower-Body Strength.

ABSTRACT: Dowse, RA, Secomb, JL, Bruton, M, Parsonage, J, Ferrier, B, Waddington, G, and Nimphius, S. Ankle proprioception in male and female surfers and the implications of motor experience and lower-body strength. J Strength Cond Res 36(12): 3497-3504, 2022-The primary objectives were to evaluate if the active movement extent discrimination apparatus (AMEDA) condition (i.e., front foot and back foot plantarflexion, dorsiflexion, inversion, and eversion) and the level of competition explained ankle movement discrimination scores and, thereafter, examined the contribution of surf experience, physical capacity, and ability to proprioception. It was also considered important to re-evaluate the surf experience, anthropometric characteristics, physical capacities, and abilities of male and female surfers. Twenty-six male ( n = 12, surf experience = 18 ± 8 years) and female surfers ( n = 14, surf experience = 9 ± 6 years) completed a pre-exercise medical questionnaire, anthropometric assessment, 8 AMEDA assessments, countermovement jump, squat jump, and isometric midthigh pull assessment. The AMEDA condition and level of competition did not have a statistically significant main effect on ankle movement discrimination scores; however, the effect of the gender/sex was significant ( p = 0.044). Surf experience ( p = 0.029) and lower-body isometric strength ( p = 0.029) had a statistically significant but small main effect on ankle movement discrimination scores. The results also confirmed that there were significant differences in surf experience, anthropometric characteristics, physical capacity, and jumping ability between male and female surfers. As surf experience and physical capacity were only able to explain a small magnitude of ankle movement discrimination scores, it is suggested that ankle proprioception in surfers may be related to both the volume and quality of the motor experience attained, which may be augmented by environmental and sociocultural factors.

Effects of Pre-exercise Acute Vibration Training on Symptoms of Exercise-Induced Muscle Damage: A Systematic Review and Meta-Analysis.

ABSTRACT: Tan, J, Shi, X, Witchalls, J, Waddington, G, Lun Fu, AC, Wu, S, Tirosh, O, Wu, X, and Han, J. Effects of pre-exercise acute vibration training on symptoms of exercise-induced muscle damage: a systematic review and meta-analysis. J Strength Cond Res 36(8): 2339-2348, 2022-Exercise-induced muscle damage (EIMD) normally occurs after unaccustomed high-intensity eccentric exercises. Symptoms of EIMD include delayed-onset muscle soreness (DOMS), tenderness, stiffness, swelling, reduced strength, and increased creatine kinase (CK) levels in the blood. Vibration training (VT) may be useful as a pre-exercise intervention in attenuating EIMD on the basis of tonic vibration reflex (TVR) through a more efficient distribution of contractile stress over muscle fibers. The objective of this meta-analysis is to examine the effects of acute VT on symptoms of EIMD when performed as the pre-exercise intervention. Randomized controlled trials (RCTs) published in the 8 databases of Cochrane Library, PubMed, Embase, Web of Science, EBSCO, China National Knowledge Infrastructure, Airiti Library and WanFang Data from 1966 (the earliest available time) to January 2019 were searched. A total of 2,324 records were identified and 448 articles were screened with the title and abstract. Two investigators identified eligible studies, extracted data, and assessed the risk of bias independently. Review Manager 5.3 designed by Cochrane was used for the current meta-analysis. Six RCTs involving 180 subjects were included in the analysis. A low-to-moderate methodological quality of the included studies was revealed using the physiotherapy evidence database scale. The results showed that acute VT was superior to the control group for the reduction of DOMS on pain visual analogue scale at 24, 48 hours and pressure pain threshold at 24 hours. In addition, superior effects of acute VT were also found on the indirect markers of muscle damage including CK at 24, 72 hours, and lactate dehydrogenase at 24 hours. The current meta-analysis has collated the evidence to demonstrate that receiving acute VT before unaccustomed high-intensity eccentric exercises may be effective in attenuating markers of muscle damage and the development of DOMS when compared with a control group. The possible mechanisms of this effect could be attributed to an improved synchronization of muscle fiber caused by TVR, which could result in even distribution of exterior loads and eventually attenuate disruptions of muscle fibers. In addition, increased blood flow may also be helpful to prevent accumulation of metabolic substances and attenuate subsequent symptoms of EIMD. Vibration training may be used as a pre-exercise intervention to alleviate symptoms of EIMD caused by unaccustomed high-intensity eccentric exercise. Because of the limited quantity and quality of included studies, more high-quality studies are required to ascertain the effect of VT on symptoms of EIMD.

Proprioceptive accuracy after uni-joint and multi-joint patterns of arm-raising movements directed to overhead targets.

AIM: To determine the effect of arm-raising pattern on upper limb proprioceptive accuracy for movements made to overhead targets. MATERIALS AND METHODS: Sixteen healthy young adults were tested in standing with arms at the sides, made dominant arm-raising movements to an unseen overhead stop, randomly placed at one of five different overhead targets. Movements were made either as a uni-joint shoulder flexion movement in an arc, or as an unconstrained arm raising that was a series of multi-joint movements involving the shoulder, elbow, and wrist. RESULTS: Overall proprioceptive accuracy for discrimination between the five unseen overhead targets was not different after arm-raising with either a uni-joint or mult-joint pattern (F1, 15 = 0.50, p = 0.49, partial η2 = 0.03). Better performers with one pattern also tended to perform well with the other (r = 0.70, p = 0.003). Trend analysis across the 4 pairwise scores for discriminations between the target positions (171.8°-173.6°, 173.6°-175.4°, 175.4°-177.2°, and 177.2°-179.0°) showed worsening discrimination towards the more distant targets (F1, 15 = 8.44, p = 0.01, partial η2 = 0.36). However, this linear trend of falling discrimination accuracy was not different between the two movement patterns (p = 0.27). CONCLUSION: Proprioceptive accuracy did not differ between simple uni-joint and more complex multi-joint arm-raising movement patterns, and the further the extent of the overhead target movement, the worse proprioceptive discrimination sensitivity for both movement patterns. Upper limb proprioceptive accuracy was therefore movement extent dependent, but movement pattern independent.

Vibration of calf muscles has reverse effects on right and left ankle proprioception in high and low proprioceptive performer groups.

PURPOSE: Previous research has found hemispheric asymmetries in the utilization of proprioceptive information. It is undetermined, however, if there is any change in asymmetry in proprioceptive function when external stimulation, such as vibration, is presented. The present study was to investigate the immediate effects of vibration stimulation (VS) on bilateral ankle proprioception. MATERIALS AND METHODS: Forty-six recreational male basketball players were included. Proprioception was assessed by using the active movement extent discrimination apparatus (AMEDA) in standing, and vibration was provided by using a vibrating form roller on the peroneal or gastrocnemius muscles. RESULTS: When participants were divided into high score and low score groups, according to the median of the baseline proprioceptive performance, VS (irrespective of whether vibrating the peroneal or gastrocnemius muscles) significantly improved left non-dominant ankle proprioception in the low proprioceptive performer group (p = 0.019), while significantly deteriorated right dominant ankle proprioception in the high proprioceptive performer group (p = 0.011). CONCLUSIONS: The results found that external stimuli reversely affect proprioception in better and worse performing groups. This suggests that there are differences in the processing of external stimulus signals on different bilateral hemispheres and in different groups (high score vs low score groups), which may be related to hemispheric asymmetry and stochastic resonance. Therefore, it is necessary to explore more specific interventions in the future.

Can Achilles and patellar tendon structures predict musculoskeletal injuries in combat soldiers?

Aiming to investigate whether Achilles tendon (AT) structure and patellar tendon (PT) structure are risk factors for musculoskeletal injuries in combat soldiers, 168 participants were recruited from an infantry commander's course. The AT and PT were examined pre-course using UTC to capture the structure of four echo-type fibers (I-IV). All injuries were assessed by military physicians pre-course and throughout the 14-week course. Soldiers who were injured during the course had a significantly higher pre-course prevalence of AT and PT echo-type III and echo-type IV compared to soldiers that were not injured during the course. Variables that were found to be associated with injured/non-injured participants were echo-type III + IV of the PT (OR = 1.44, 95% CI = 1.24-1.68) and echo-type III of the AT (OR = 1.69, 95% CI = 1.35-2.12). ROC analyses showed that the best model, exhibiting both high sensitivity and low specificity, was that participants with PT echo-type III + IV > 10% or AT echo-type III >8.5% had the highest risk of being injured during the course. In conclusions, the tendon structure at the beginning of high-intensity activity or physical training program might be a risk factor for subsequent injury during the course. Soldiers and high-level athletes should be aware of the cutoff points for fiber types in tendon structure that might put them at high risk for future injury. At-risk soldiers/athletes should be provided with an intervention program before they start their training program, with the aim of improving the tendon structure and preventing subsequent injury.

Generalized joint hypermobility, scoliosis, patellofemoral pain, and physical abilities in young dancers.

BACKGROUND: Many young girls with generalized joint hypermobility (GJH) choose to participate in dance because their bodies are suited for this activity. Scoliosis tends to occur often in thin girls, who also are more likely to choose dance. Both anomalies (GJH and scoliosis) may be related to reduced abilities such as diminished strength and insufficient postural balance, with increased risk for musculoskeletal conditions. The main objectives of the present study were to determine the prevalence of dancers with GJH, the prevalence of dancers with scoliosis, and the prevalence of dancers with these two anomalies; and, to determine differences in physical abilities and the presence of patellofemoral pain (PFP) between young female dancers with and without such anomalies. METHODS: One hundred thirty-two female dancers, aged 12-14 years, were assessed for anthropometric parameters, GJH, scoliosis, knee muscle strength, postural balance, proprioception ability, and PFP. RESULTS: GJH was identified in 54 dancers (40.9%) and scoliosis in 38 dancers (28.8%). Significant differences were found in the proportion of dancers with no anomalies (74 dancers, 56.1%) and dancers with both anomalies (34 dancers, 25.8%) (p < .001). Dancers with both anomalies had reduced dynamic postural balance in the anterior direction (p = .023), reduced proprioception ability (p < .001), and weaker knee extensors (p = .036) and flexors (p = .040) compared with dancers with no anomalies. Among dancers with both anomalies, 73.5% suffered bilateral PFP, 17.6% suffered unilateral PFP, and 8.8% had no PFP (p < .001). CONCLUSIONS: A high prevalence of young girls participating in dance classes had GJH, as the increased joint flexibility probably provides them with some esthetic advantages. The high prevalence of scoliosis found in these young dancers might be attributed to their relatively low body mass, their delayed maturation, and the selection process of dancers. Dancers with both GJH and scoliosis had decreased muscle strength, reduced postural balance, reduced proprioception, with higher risk of PFP. The main clinical implications are the need to reduce the risk of PFP among dancers by developing appropriate strength and stabilizing exercises combined with proprioceptive and postural balance training, to improve the correct alignment of the hyperextended and hypermobile joints, and to improve their supporting muscle strength.

Prevalence of impaired physiological function consistent with Relative Energy Deficiency in Sport (RED-S): an Australian elite and pre-elite cohort.

OBJECTIVES: Athlete health, training continuity and performance can be impeded as a result of Relative Energy Deficiency in Sport (RED-S). Here we report the point prevalence of symptoms described by the RED-S model in a mixed-sport cohort of Australian female athletes. METHODS: Elite and pre-elite female athletes (n=112) from eight sports completed validated questionnaires and underwent clinical assessment to assess the point prevalence of RED-S symptoms. Questionnaires included the Depression, Anxiety and Stress Questionnaire (DASS-21), Generalized Anxiety Disorder (GAD-7), Center for Epidemiological Studies Depression Scale (CES-D), SCOFF questionnaire for disordered eating, Low Energy Availability in Females Questionnaire (LEAF-Q), and a custom questionnaire on injury and illness. Clinical assessment comprised resting metabolic rate (RMR) assessment, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, venous and capillary blood samples, and the Mini International Neuropsychiatric Interview (MINI 7.0.2). Descriptive prevalence statistics are presented. RESULTS: Almost all (80%) participants (age 19 (range 15-32) years; mass 69.5±10.3 kg; body fat 23.1%±5.0%) demonstrated at least one symptom consistent with RED-S, with 37% exhibiting between two and three symptoms. One participant demonstrated five symptoms. Impaired function of the immunological (28%, n=27), haematological (31%, n=33) and gastrointestinal (47%, n=51) systems were most prevalent. A moderate to high (11%-55%) prevalence of risk of low energy availability was identified via RMR and LEAF-Q, and identified mental illnesses were prevalent in one-third of the assessed cohort. CONCLUSION: Symptoms described by the RED-S model were prevalent in this cohort, supporting the need for improved awareness, monitoring and management of these symptoms in this population.

The Utility of the Low Energy Availability in Females Questionnaire to Detect Markers Consistent With Low Energy Availability-Related Conditions in a Mixed-Sport Cohort.

The Low Energy Availability in Females Questionnaire (LEAF-Q) was validated to identify risk of the female athlete triad (triad) in female endurance athletes. This study explored the ability of the LEAF-Q to detect conditions related to low energy availability (LEA) in a mixed sport cohort of female athletes. Data included the LEAF-Q, SCOFF Questionnaire for disordered eating, dual-energy X-ray absorptiometry-derived body composition and bone mineral density, Mini International Neuropsychiatric Interview, blood pressure, and blood metabolic and reproductive hormones. Participants were grouped according to LEAF-Q score (≥8 or <8), and a comparison of means was undertaken. Sensitivity, specificity, and predictive values of the overall score and subscale scores were calculated in relation to the triad and biomarkers relevant to LEA. Fisher's exact test explored differences in prevalence of these conditions between groups. Seventy-five athletes (18-32 years) participated. Mean LEAF-Q score was 8.0 ± 4.2 (55% scored ≥8). Injury and menstrual function subscale scores identified low bone mineral density (100% sensitivity, 95% confidence interval [15.8%, 100%]) and menstrual dysfunction (80.0% sensitivity, 95% confidence interval [28.4%, 99.5%]), respectively. The gastrointestinal subscale did not detect surrogate markers of LEA. LEAF-Q score cannot be used to classify athletes as "high risk" of conditions related to LEA, nor can it be used as a surrogate diagnostic tool for LEA given the low specificity identified. Our study supports its use as a screening tool to rule out risk of LEA-related conditions or to create selective low-risk groups that do not need management as there were generally high negative predictive values (range 76.5-100%) for conditions related to LEA.

Injury Prevention Exercises for Reduced Incidence of Injuries in Combat Soldiers.

ABSTRACT: Steinberg, N, Bar-Sela, S, Moran, U, Pantanowitz, M, Waddington, G, Adams, R, Band, SS, and Funk, S. Injury prevention exercises for reduced incidence of injuries in combat soldiers. J Strength Cond Res 35(11): 3128-3138, 2021-The aim of this study was to determine the influence of an "all-cause injury" prevention program, focused on static-to-dynamic transitions, on injury prevalence in a military commanders course. Two cohorts of male infantry commanders were recruited (intervention [INT group], n = 196 and controls [CO group], n = 169) and tracked by a physiotherapist, who recorded any injuries that occurred during the 14-week course. Soldiers were tested precourse, midcourse, and postcourse for anthropometrics, proprioception ability, and dynamic postural balance (DPB). The INT group performed injury prevention exercises for 5 minutes, 3 times a week, and the CO group continued with their routine physical fitness sessions. The prevalence of injuries reported to the physiotherapist during the course was significantly lower for the INT group compared with the CO group (14.8 and 34.3%, respectively, p < 0.001). Similarly, rates of injury in the INT group were significantly lower than in the CO group (p < 0.001; hazard = 2.53, 95% confidence interval = 1.62-3.95). Precourse proprioception ability was significantly lower in those that became injured during the commanders course, irrespective of the group. Likewise, for DPB parameters, the injured subjects in both groups had significantly lower precourse scores than the noninjured subjects. From pretesting to midtesting, the injured soldiers in the INT group improved their ability up to the level of the noninjured subjects. A reduced prevalence of injuries was found for soldiers who completed the injury prevention program. Because the subjects soldiers injured on the course had reduced somatosensory abilities at the outset, and as these abilities can be improved by static-to-dynamic exercises, identifying at-risk soldiers and providing them with appropriate strategies for improvement beforehand is indicated.

Key viral immune genes and pathways identify elite athletes with URS.

PURPOSE: Habitual intense exercise may increase the incidence of upper respiratory symptoms (URS) in elite athletes. This study investigated whether immune gene expression could identify gene markers that discriminate athletes with a higher prevalence of URS. METHODS: This cross-sectional analysis of elite Australian athletes from various sports investigated whether athletes retrospectively reporting URS for two days or more in a month (n=38), had an altered immune gene expression profile compared with asymptomatic athletes (n=33). Peripheral blood samples were collected during Olympic selection events with corresponding URS data collected for the one-month period before sampling. Digital immune gene expression analysis was undertaken using the NanoString PanCancer Immune Profiling panel. RESULTS: Fifty immune genes were differentially expressed between the groups (p<0.05) and approximately 78% of these genes were more highly expressed in athletes reporting URS. Many of these genes were interferon-stimulated genes or genes involved in the Jak/Stat signalling pathway. Only interferon alpha inducible protein 27 (IFI27), an interferon stimulated gene involved in viral response, remained significantly higher in athletes reporting URS (log2 fold-difference=2.49, odds ratio 1.02 per unit increase; p<0.01) post-adjustment and discriminated athletes reporting URS from asymptomatic athletes with 78% accuracy. CONCLUSIONS: Expression of IFI27 could differentiate athletes reporting URS from asymptomatic athletes, a gene that is upregulated in the immune response to viral infection. Upregulation of viral signalling pathways provides novel information on the potential aetiology of URS in elite Olympic athletes.

Joint position reproduction and joint position discrimination at the ankle are not related.

Purpose: Limited data in current literature can be found on the relation between the two commonly-used active proprioception assessment methods -active joint position reproduction (JPR) and active movement extent discrimination assessment (AMEDA). The current study compared the two active methods, JPR and AMEDA, to investigate their interrelationship over two studies that differed in task difficulty, using active ankle inversion movements made in weight-bearing to maximise ecological validity.Methods: 50 participants volunteered in this research, 20 of whom on a harder protocol and the other 30 on an easier protocol, were tested by both methods, JPR and AMEDA. Proprioceptive acuity was represented by absolute error (AE) and variable error (VE) for JPR and by AE and the area under the curve (AUC) for AMEDA.Results: Proprioceptive acuity scores are found to be significantly correlated within test methods but not between methods for either hard or easy tasks, where JPR AE and VE scores were not correlated with either AMEDA AE or AUC. Further, proprioceptive acuity scores were significantly higher on the easy task when tested with the AMEDA method, but not with JPR method.Conclusion: Scores obtained from the two active movement proprioception tests, movement extent discrimination and joint position reproduction, were not significantly correlated. Taken together with previous findings, these results show that for proprioception, scores from the three classical psychophysical methods for measuring sensitivity (adjustment, limits and constant stimuli) are not correlated with each other. This suggests that each proprioception measurement system assesses a different aspect of proprioception.

Glucocorticoid prescribing habits of sports medicine physicians working in high-performance sport: a 30-nation survey.

OBJECTIVES: Glucocorticoids are commonly prescribed in medicine. When administered via certain routes, glucocorticoids are prohibited for incompetition use by WADA. The glucocorticoid prescribing habits of sports medicine doctors have not been reported. METHODS: An online survey was distributed internationally to physicians working in high-performance sports. The survey queried the doctors about their use of glucocorticoids with athletes and their understanding of WADA's regulations regarding glucocorticoid use in competition. RESULTS: 603 sports medicine doctors from 30 different countries participated. The majority (>85%) routinely injected glucocorticoids and/or prescribed glucocorticoids by other routes. There were substantial differences in the common routes of injection as well as types of glucocorticoid used among the physicians from various countries. A relatively small percentage of sports doctors (<25%) accurately identified which routes of glucocorticoid administration are prohibited in competition by WADA. There was a great variation in how long before competition the use of glucocorticoids would cause the doctor to consider applying for a therapeutic use exemption (TUE). A better understanding of the clearance rates of glucocorticoids from athletes' bodies would greatly aid sports medicine doctors' decisions on how and when to apply for a TUE. A small number of doctors had observed side effects of glucocorticoid administration, with the majority of side effects being minor in nature. CONCLUSION: Glucocorticoids are widely prescribed by sports physicians. There is a need to better educate sports physicians on the current WADA regulations in relation to glucocorticoid administration.

Unilateral and bilateral patellofemoral pain in young female dancers: Associated factors.

Aiming to evaluate the prevalence of unilateral/bilateral patellofemoral pain (PFP) among young dancers, and to investigate whether different factors are associated with PFP in young dancers, 132 dancers aged 12-14 years were assessed for PFP. Anthropometric parameters, proprioception ability, dynamic postural balance (DPB), and muscle strength were measured. PFP was found in 64.1% of the dancers. No significant differences in the prevalence of dancers with no, unilateral, or bilateral PFP at different ages were found. Significant age effects were found for anthropometric and developmental measurements, and for intensity of training. PFP effect was found for DPB asymmetry, ankle proprioception, and leg-length %height. A higher hip abductor/adductor ratio was associated with PFP in 14-year-old dancers. Binomial logistic regression showed that increased number of hours per day (h/day) and decreased number of hours per week (h/week), low proprioception scores, greater leg length as %height, and more anterior DPB asymmetry were significant predictors of PFP. In conclusion: unilateral/bilateral PFP is common among young dancers. Body morphology, reduced ankle proprioception ability, DPB asymmetry, and increased h/day of practice are associated with PFP. Dance teachers should start monitoring the impact of training and implement injury modification/prevention strategies when their students are at a young age.

Shoulder internal and external rotation strength and prediction of subsequent injury in water-polo players.

Water-polo players have greater isokinetic shoulder strength than age-matched controls. Due to the repetitive demands of throwing, however, water-polo players demonstrate an altered strength ratio, with greater internal rotation (IR) strength relative to external rotation (ER). The relationship between shoulder strength and risk of shoulder injury is unknown. In addition, the effect on test position for strength testing on the reliability of handheld dynamometry (HHD) in this population is not known. The aims were to determine the: (a) Inter-rater reliability of HHD testing of IR and ER strength in two positions: neutral and 90°abduction-90°ER (90-90) and (b) relationship between preseason shoulder strength and occurrence of future injury in sub-elite water-polo players. Two assessors measured shoulder IR and ER strength using HHD in 15 water-polo players across two testing days. Athletes were followed over a 6-month period, and injury was assessed and recorded by the team physiotherapist. Measurement of water-polo players' isometric IR and ER strength in the clinical setting had good to excellent inter-rater reliability; however, systematic error was observed in the neutral position but not the 90-90 position. Irrespective of testing position, the neutral and 90-90 test position showed a significant difference (P = 0.01) in absolute preseason IR and ER mean strength between prospectively injured and non-injured players. There was no significant difference in strength ratio or strength normalized for body mass index. These results suggest that preseason strength testing may help identify players at risk of in-season shoulder injury.

Throwing performance in water polo is related to in-water shoulder proprioception.

Water polo players require a high level of upper-extremity strength, flexibility and coordination to achieve a peak level of throwing performance. Increased levels of shoulder proprioceptive acuity, strength and range of motion (ROM) have been previously associated with higher sporting performance. A coach-rating scale, used to quantify an athlete's kicking proficiency in soccer; was adapted in the current study to measure each coach's subjective expert opinion regarding athletes' throwing mechanics, velocity, and accuracy. To examine this hypothesis shoulder proprioception acuity of 18 water polo players was measured both in-water and on-land using an AMEDA apparatus and correlated with coach-rated throwing performance and clinical measures of shoulder strength and ROM. There was a moderate positive correlation between the in-water and the on-land proprioception acuity (r = 0.47, p < 0.05). The in-water score showing a strong positive correlation with coach rated throwing mechanics (r = 0.68, p < 0.05) and velocity (r = 0.75, p = 0.02), suggesting that superior proprioception acuity contributed to fast, mechanically-efficient throwing. These findings support the notion that in-water proprioceptive acuity is an important determinant of the throwing performance achieved by water polo athletes and its measurement may be a valuable adjunct to current athlete screening.

Effects of Textured Balance Board Training in Adolescent Ballet Dancers With Ankle Pathology.

CONTEXT: Ankle sprains are common among adolescent ballet dancers and may be attributed to inadequate ankle proprioception. Thus, a short period of training utilizing proprioceptive activities requires evaluation. OBJECTIVE: To assess training conducted for 3 or 6 weeks on a textured-surface balance board using ankle proprioception scores for ballet dancers with and without chronic ankle instability, and with and without previous ankle sprain (PAS). DESIGN: Intervention study. SETTING: The Australian Ballet School. PARTICIPANTS: Forty-two ballet dancers, aged 14-18 years. INTERVENTIONS: Dancers randomized into 2 groups: group 1 undertook 1 minute of balance board training daily for 3 weeks; group 2 undertook the same training for 6 weeks. MAIN OUTCOME MEASURES: Preintervention, Cumberland Ankle Instability Tool questionnaire data were collected, and PAS during the last 2 years was reported. Active ankle inversion movement discrimination ability was tested immediately pre and post intervention and at 3 and 4 weeks. RESULTS: Ankle discrimination acuity scores improved over time for both groups, with a performance decline associated with the early cessation of training for group 1 (P = .04). While dancers with PAS had significantly worse scores at the first test, before balance board training began (P < .01), no significant differences in scores at any test occasion were found between dancers with and without chronic ankle instability. A significantly faster rate of improvement in ankle discrimination ability score over the 4 test occasions was found for dancers with PAS (P = .002). CONCLUSIONS: Three weeks of textured balance board training improved the ankle discrimination ability of ballet dancers regardless of their reported level of chronic ankle instability and at a faster rate for dancers with PAS. Previous ankle sprain was associated with a lower level of ankle discrimination ability; however, following 3 weeks of balance board training, previously injured dancers had significantly improved their ankle discrimination acuity scores.

Recent Ankle Injury, Sport Participation Level, and Tests of Proprioception.

OBJECTIVE: Assessing the effects of ankle injury and sport participation level on ankle proprioceptive sensitivity using a joint position reproduction (JPR) test and an inversion movement extent discrimination test. DESIGN: Cross-sectional. SETTING: Biomechanics lab. PARTICIPANTS: Forty-five student athletes ages 21-30 (mean = 24.8 y). MAIN OUTCOME MEASURES: Participants were tested for ankle inversion sensitivity using 2 devices; movement reproduction error was obtained from JPR in a non-weight-bearing (N-WB) state at 10° and 15° of inversion, and an ankle proprioceptive sensitivity score was obtained from the active movement extent discrimination apparatus (AMEDA), representing the ability to differentiate 5 inversion movement extents between 10.5° and 14.5°, with testing in both N-WB and weight-bearing (WB) states. RESULTS: For the 34 athletes with no ankle injury in the previous 12 months, the sensitivity scores achieved on the AMEDA were significantly higher (P < .01) than those for the 11 athletes with ankle injury, and the injury effect was significantly greater in WB (P = .01). In JPR testing, the 2.96° error of reproduction for athletes with no recent ankle injury was not significantly different from the 3.36° error for those with ankle injury (P = .46). Correlation of current sport participation level with JPR showed less error for higher-level performers (r = .49, P = .001) but no significant relationship to WB or N-WB AMEDA scores (both P > .61). WB AMEDA scores were significantly higher for athletes who had competed at a higher level of sport competition when <18 years old (r = -.57, P < .001). CONCLUSIONS: Previous ankle sprains affected proprioceptive scores on the WB AMEDA and N-WB AMEDA tests, indicating the sensitivity of the AMEDA movement discrimination test to the effects of ankle injury. The correlation between JPR scores and current level of sport participation suggests the sensitivity of the JPR test to current ankle use.