Context: Inappropriate activation of the anterolateral abdominal muscles affects the stability of the lumbopelvic zone and increases the appearance of pain and lesion in the area. Therefore, ways to improve its effective contraction are crucial in rehabilitation. The aim of this study was to compare the activation of the transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) muscles in 3 different pelvic positions (down pelvis [DP], horizontal pelvis [HP], and up pelvis [UP]) during sling bridge exercise (SBE) to determinate which position is more effective to promote a correct contraction of the anterolateral abdominal muscles. Design: Cross-sectional study. Methods: Fifteen participants performed 3 variations (DP, HP, and UP) of a one-legged exercise called “supine pelvic lift” on a sling device. The thicknesses of the TrA, IO, and EO were recorded at rest and at the 3 positions using ultrasound imaging. Thickness, change ratio, lateral slide of TrA, and preferential and contraction activation ratio of TrA, IO, and EO were analyzed. Results: TrA and IO showed greater activation (P = .01) in the UP position than the other pelvic positions. In addition, UP position decreased the activation of the EO (P = .01). Conclusion: Based on the results of this study, SBE in the UP position has the potential to improve normal contraction patterns of the musculature and can be used in future intervention of the lumbopelvic zone.
Seungmin Kim, Jhosedyn Carolaym Salazar Fajardo, and BumChul Yoon
Tamara R. Cohen, Brent Rosenstein, Amanda Rizk, Stephane Frenette, and Maryse Fortin
Context: Measures of side-to-side asymmetry in body composition may help identify players who are predisposed to lower limb injuries (LLI) or lower back pain (LBP). This study aimed to examine (1) side-to-side asymmetry in college rugby players according to sex and position and (2) whether side-to-side asymmetry is associated with LBP or LLI. Design: Cross-sectional study. Methods: Thirty-six rugby players (61% female) underwent a dual-energy X-ray absorptiometry assessment for total and regional (appendicular, truncal) outcomes of fat mass, lean mass, and bone mass. A subsample (n = 23) of players had a second dual-energy X-ray absorptiometry assessment 2 months postbaseline. Two-way analysis of variance was used to assess the effect of position (forward and backs) and sex on body composition asymmetry. Student paired t tests were used to assess side-to-side difference in body composition and compare baseline and follow-up measures. Logistic regression was used to assess possible associations between LLI, LBP, and the degree of side-to-side asymmetry in body composition. Results: Male players had greater asymmetry in arm bone mass compared with female players (P = .026), and trunk fat mass asymmetry was greater in forwards as compared with backs (P = .017). Forwards had significantly greater fat mass (P = .004) and percentage of fat (P = .048) on the right leg compared with the left. Backs had significantly greater bone mass in the right arm compared with the left (P = .015). From baseline to postseason, forwards had a significant increase in side-to-side asymmetry in arm lean mass (P = .006) and a significant decrease in side-to-side asymmetry in leg fat mass (P = .032). In backs, side-to-side asymmetry at baseline compared with postseason was significantly different (P = .011) for trunk fat mass. There were no significant associations between body composition asymmetry, LLI, or LBP by sex or position. Conclusion: Our results revealed the presence of side-to-side asymmetries in body composition in university rugby players between sex and position. The amount of asymmetry, however, was not associated with LBP and LLI.
Brantley K. Ballenger, Emma E. Schultz, Melody Dale, Bo Fernhall, Robert W. Motl, and Stamatis Agiovlasitis
This systematic review examined whether physical activity interventions improve health outcomes in adults with Down syndrome (DS). We searched PubMed, APA PsycInfo, SPORTDiscus, APA PsycARTICLES, and Psychology and Behavioral Sciences Collection using keywords related to DS and physical activity. We included 35 studies published in English since January 1, 1990. Modes of exercise training programs included aerobic exercise, strength training, combined aerobic and strength training, aquatic, sport and gaming, and aerobic and strength exercise interventions combined with health education. The evidence base indicates that aerobic and strength exercise training improve physical fitness variables including maximal oxygen uptake, maximal heart rate, upper and lower body strength, body weight, and body fat percentage. Sport and gaming interventions improve functional mobility, work task performance, and sport skill performance. We concluded that adults with DS can accrue health benefits from properly designed physical activity and exercise interventions.
Brynn Adamson, Mina Woo, Toni Liechty, Chung-Yi Chiu, Nic Wyatt, Cailey Cranny, and Laura Rice
Lack of disability awareness of fitness professionals is a well-established barrier to exercise participation among people with disabilities that is likely related to the lack of disability awareness training for group fitness instructors. The purposes of this study were to develop, implement, and evaluate a disability awareness training for group fitness instructors. A 90-min video training and resource manual were developed. We recruited 10 group fitness instructors from one recreation center to participate. Participants completed baseline, posttraining, and 2-month follow-up testing on survey-based outcomes including disability attitudes, confidence in exercise adaptations, and training satisfaction. Participants’ confidence to adapt fitness classes was significantly improved; however, disability attitudes were high in the pretest and not significantly different posttraining. Semistructured interviews were conducted posttraining and revealed three themes: Formal disability training is needed, Managing inclusive class dynamics, and Training suggestions and satisfaction. This training demonstrated a feasible intervention for increasing disability awareness among community-based group fitness instructors.
Eric J. Shumski, Tricia M. Kasamatsu, Kathleen S. Wilson, and Derek N. Pamukoff
Context: Induced mental fatigue negatively impacts sport performance and neurocognition. However, it is unclear how induced mental fatigue influences landing biomechanics. The purpose of this study was to examine the influence of mental fatigue on drop landing biomechanics in individuals with and without a concussion history.
Design: Crossover design.
Methods: Forty-eight (24 per group) recreationally active individuals were matched on age (±3 y), sex, and body mass index (±1 kg/m2). All participants completed an experimental (30-min Stroop task) and control (30-min reading magazines) intervention on separate days separated by a minimum of 24 hours. Drop landings were performed before and after both interventions. Outcomes included peak vertical ground reaction force (vGRF), vertical loading rate (VLR), knee flexion angle, knee abduction angle, external knee flexion moment, external knee abduction moment, and initial ground contact knee flexion and knee abduction angles. Separate 2 (group) × 2 (intervention) between-within analyses of covariance compared drop landing outcomes. Each group’s average pre-Stroop and premagazine outcomes were covariates.
Results: There was a significant interaction for vGRF (P = .033,
Filiz Başol, İlke Kara, and Tülay Çevik Saldıran
Objectives: The whole-body vibration (WBV) effects on muscle strength show inconsistent results. Moreover, there is no study about the WBV effect on stiffness, elasticity, and muscle strength. Therefore, the study aimed to examine the effect of WBV exposure with static squat posture on the stiffness, elasticity, and strength of the lower-limb extensor muscles. Material and Methods: Forty healthy untrained young adults were divided into WBV and control groups. The experimental group received WBV exposure on 2 nonconsecutive days of the week, for 6 weeks. The MyotonPRO device was used for the assessment of the knee extensor and the ankle dorsiflexors’ stiffness and elasticity. Isometric muscle strength was evaluated with a hand-held dynamometer. All measurements were done by the same assessor at baseline, and the following 6 weeks. Results: Significant group-by-time interactions were found for the elasticity scores of the right (d = 0.84, P = .01) and left (d = 0.77, P = .02) ankle dorsiflexors. Similar to the elasticity measurements, significant group-by-time interactions were observed in the muscle strength scores of the right (d = 0.45, P = .046) and left (d = 1.25, P < .001) ankle dorsiflexors. No significant effects were observed in any of the evaluated muscle stiffness measurements (P > .05), and there was no significant group-by-time interaction in knee-extensor muscle strength and elasticity scores (P > .05). Conclusions: The study results indicate that if the ankle dorsiflexor strength and elasticity are desired to be increased, the 6-week WBV exposure in a static squat posture can be used in healthy individuals.
Nahid Pirayeh, Farshid Razavi, Amin Behdarvandan, and Neda Mostafaee
Background: The Anterior Cruciate Ligament-Return to Sport after Injury scale (ACL-RSI) is used to measure athletes’ psychological readiness in terms of their emotions, confidence in performance, and risk appraisal with respect to return to sport after ACL reconstruction. Objective: To translate and cross-culturally adapt the ACL-RSI to the Persian version and evaluate the reliability and validity of this scale in patients with ACL reconstruction. Study Design: Clinical measurement study (psychometric analysis). Methods: To assess test–retest reliability, 100 participants were asked to complete the Persian version of the ACL-RSI 2 times with a 7- to 10-day interval. In the first assessment, the patients also filled the Injury-Psychological Readiness to Return to Sport Questionnaire, Tampa Scale of Kinesiophobia, International Knee Documentation Committee Subjective Knee Form, and Knee Injury and Osteoarthritis Outcome Score. Internal consistency (Cronbach alpha, α), test–retest reliability (intraclass correlation coefficients), measurement error (standard error of measurement and minimum detectable change), and construct validity (Pearson r) were determined. Results: Our results showed good internal consistency (Cronbach alpha = .94) and excellent test–retest reliability (intraclass correlation coefficients = .90 (.85−.93)]. Standard error of measurement and minimum detectable change were 4.64 and 12.85, respectively. No significant bias was observed between test and retest. In addition, based on the results of correlation analysis, all hypotheses of this study were confirmed. The Persian version of the ACL-RSI had a strong correlation with Injury-Psychological Readiness to Return to Sport (I-PPR) (P < .001, r = .76) and Tampa scale of Kinesiophobia (TKS) (P < .001, r = −.68). Furthermore, a moderate correlation was observed between the Persian version of the ACL-RSI and the International Knee Documentation Committee Subjective Knee Form (P < .001, r = .44) and between this version of the ACL-RSI and the subscales of Knee Injury and Osteoarthritis Outcome Score (P < .001, r = .30–.55). Conclusion: Given its acceptable reliability and validity, the Persian version of the ACL-RSI seems to be a suitable tool for evaluating psychological readiness to return to sport after ACL reconstruction.
Seok-Hyun Kim, Heon-Seock Cynn, Chung-Hwi Yi, Ji-Hyun Lee, and Seung-Min Baik
Context: Wall push-up plus (WPP) and wall slide (WS) are commonly prescribed in early rehabilitation to increase serratus anterior (SA) muscle activity. For individuals with scapular winging (SW), synergistic muscles such as upper trapezius (UT) and pectoralis major (PM) may compensate for weak SA during scapular movement. However, no studies have applied isometric horizontal abduction (IHA) during WS in individuals with SW nor have compared it with WPP with IHA. Objectives: This study compared the effects of IHA on shoulder muscle activity during WPP and WS exercises in individuals with SW. Design: Cross-sectional study; 2-way repeated-measures analysis of variance was used to assess the statistical significance of observed differences in SA, UT, PM, lower trapezius (LT), and infraspinatus (IS) muscle activities. Setting: Research laboratory. Patients: We recruited 30 individuals with SW comprising 20 men and 10 women. Interventions: The individuals performed WPP and WS exercises with and without IHA using Thera-Band. Main Outcome Measures: Surface electromyography was used to measure muscle activity of the SA, UT, PM, LT, and IS during the isometric phase of WPP and WS. Maximal voluntary isometric contractions were recorded to normalize electromyographic data. Results: There was no significant interaction between IHA application and exercise type for any of the shoulder muscles. IHA application increased SA (P = .008), UT (P = .001), LT (P = .009), and IS (P = .000) activities and decreased PM (P = .001) activity compared with those without IHA. WS exercises elicited higher PM (P = .017) and LT (P = .011) activities than WPP. Conclusion: WPP and WS with IHA may be effective in increasing the muscle activities of shoulder stabilizers and preventing overactivation of PM activity. WPP may be recommended for individuals with overactivated PM, whereas WS may be used to increase LT activity.