Ultrasound Biofeedback Increases Abdominal Muscle Activation in Golfers With a History of Low Back Pain.

OBJECTIVES: To compare activation ratios of the transverse abdominis (TrA) during an abdominal draw-in maneuver (ADIM) and abdominal obliques during a golf swing, with and without ultrasound biofeedback, and to determine intrarater reliability of these ultrasound thickness measures. DESIGN: Single-session crossover study. SETTING: Laboratory. PARTICIPANTS: Sixteen adult golfers with 2 or more episodes of low back pain (LBP) in the past year. INTERVENTIONS: Verbal cueing alone and verbal cueing with ultrasound biofeedback. MAIN OUTCOME MEASURES: Bilateral TrA activation ratios were calculated during an ADIM with and without ultrasound biofeedback. Activation ratios of the abdominal obliques were calculated bilaterally during golf swings with and without ultrasound biofeedback. Intraclass correlation coefficients (ICCs) were calculated for average thickness across all muscles and conditions for the nonbiofeedback trials. RESULTS: Transverse abdominis activation ratios were significantly higher when ultrasound biofeedback was provided bilaterally ( P < 0.001). Abdominal oblique activation ratios during the golf swing were also significantly higher with ultrasound biofeedback for the lead ( P = 0.014) and trail ( P < 0.001) sides. Intraclass correlation coefficient values ranged from 0.92 to 0.97 ( P < 0.001). CONCLUSIONS: Ultrasound biofeedback can increase activation ratios of the TrA during a supine ADIM in adult golfers with a history of LBP. Postswing ultrasound biofeedback increases activation of the abdominal obliques during a golf swing in golfers with a history of LBP. Ultrasound thickness measures of the TrA and obliques have excellent intrarater reliability.

Innovations in the Assessment of Skeletal Muscle Health: A Glimpse into the Future.

Skeletal muscle is the largest organ system in the human body and plays critical roles in athletic performance, mobility, and disease pathogenesis. Despite growing recognition of its importance by major health organizations, significant knowledge gaps remain regarding skeletal muscle health and its crosstalk with nearly every physiological system. Relevant public health challenges like pain, injury, obesity, and sarcopenia underscore the need to accurately assess skeletal muscle health and function. Feasible, non-invasive techniques that reliably evaluate metrics including muscle pain, dynamic structure, contractility, circulatory function, body composition, and emerging biomarkers are imperative to unraveling the complexities of skeletal muscle. Our concise review highlights innovative or overlooked approaches for comprehensively assessing skeletal muscle in vivo. We summarize recent advances in leveraging dynamic ultrasound imaging, muscle echogenicity, tensiomyography, blood flow restriction protocols, molecular techniques, body composition, and pain assessments to gain novel insight into muscle physiology from cellular to whole-body perspectives. Continued development of precise, non-invasive tools to investigate skeletal muscle are critical in informing impactful discoveries in exercise and rehabilitation science.

Changes in Hip Isometric Strength of Female College Soccer Players After High-Workload Training Session.

CONTEXT: The hip adductor and abductor muscles play vital roles as stabilizers in the lower-extremity. Their activation during soccer-specific actions is essential, but local muscular fatigue can hinder athletic performance and increase the risk of injury. DESIGN: This study aimed to observe the variations in frontal plane hip strength in female college soccer players before and after a high-workload soccer-specific training session. Furthermore, the study sought to compare the relative changes in hip strength with the internal and external load measures obtained during that session. METHODS: Twenty female college soccer players participated in a retrospective observational study. Isometric hip adductor and abductor strength were measured before and after a training session in the college spring season. Measurements were taken with a handheld dynamometer (MicroFET 2) while the players were supine. Global positioning system sensors (Catapult Vector S7), commonly worn by players during training sessions and competitive matches, were used to measure external and internal loads. Statistical analyses were performed using paired samples t test to assess hip adductor and abductor strength changes before and after the training session. Spearman rank was used to identify correlation coefficients between global positioning system data and isometric hip strength. RESULTS: The findings revealed significant decreases in the strength of the right hip adduction (P = .012, -7% relative change), right abduction (P = .009, -7.6% relative change), and left abduction (P = .016, -4.9% relative change) after the training session. Furthermore, relative decreases in hip isometric adduction and abduction strength are related to the distance covered at high speeds. CONCLUSION: The results of this study highlight that hip isometric adduction and abduction strength tend to decrease after exposure to high workloads during soccer-specific training.

Exploration of the Golf-Specific Low Back Pain Questionnaire.

OBJECTIVE: The primary purpose of this study was to determine internal consistency and concurrent validity of the Golf-specific Low Back Pain questionnaire (GLBP). DESIGN: Cross-sectional study. SETTING: Online questionnaire. PARTICIPANTS: Fifty-two adult golfers with a history of LBP. INTERVENTIONS: GLBP, Oswestry Disability Index (ODI). MAIN OUTCOME MEASURES: Cronbach alpha values for the GLBP and its 3 subscales. Pearson correlations between the ODI, GLBP, and the GLBP subscales. RESULTS: Cronbach alpha for the GLBP was 0.94. Cronbach alpha for the 3 GLBP subscales ranged from 0.85 to 0.91. All Pearson correlations were significant at P < 0.05. The correlation between the ODI and GLBP was -0.64, and correlations between the ODI and GLBP subscales ranged from -0.53 to -0.63. Mean GLBP score was 72.01% ± 16.15%, and mean ODI score was 12.00% ± 7.98%. CONCLUSIONS: The GLBP has excellent concurrent validity to quantify LBP in golfers. The GLBP total and each individual subscale have excellent internal consistency and a moderate inverse relationship with the ODI. The GLBP offers a more sport-specific patient-reported outcome measure for this population. The GLBP may more adequately quantify LBP-related disability, especially at lower levels of disability. Findings provide initial evidence that the GLBP may be a valid tool to quantify LBP symptoms and dysfunction in golfers. CLINICAL RELEVANCE: Clinicians should consider using sport-specific outcome measures when evaluating for LBP-related disability.

Relationship Between Muscle Activity and Force During Suspended Bridge Exercises.

CONTEXT: Isometric core stability exercises are commonly used to target muscles of the lumbopelvic-hip complex, including the rectus abdominis (RA) and erector spinae (ES). These exercises can be implemented in rehabilitation protocols to increase muscle strength and endurance. Difficulty can be progressed by modifying the base of support or adding an unstable element. Load cells can be affixed to suspension training devices to measure force exerted through the straps during exercise. The primary purpose of this study was to assess the relationship between activity of the RA and ES to force measured through a load cell fixed to suspension straps during bilateral and unilateral suspended bridge exercises. DESIGN: Forty asymptomatic, active individuals completed a single laboratory visit. METHODS: Participants completed 2 bilateral suspended bridges and 2 unilateral suspended bridges held to failure. Surface electromyography sensors were placed over the bilateral RA and ES to quantify muscle activity (% maximum voluntary isometric contraction). A load cell was affixed to the suspension straps to measure force exerted through the straps throughout the duration of the exercise. Pearson correlations were used to determine relationships between force and muscle activity of the RA and ES throughout exercise duration. RESULTS: Force was negatively related to RA muscle activity in bilateral suspended bridges (r = -.735 to -.842, P < .001) and unilateral suspended bridges (r = -.300 to -.707, P = .002 to <.001). Force had a positive relationship with ES muscle activity in bilateral suspended bridges (r = .689 to .791, P < .001) and unilateral suspended bridges (r = .418 to .448, P < .001). CONCLUSIONS: Suspended bridge exercises can be a valuable tool to target posterior abdominal musculature such as the ES to contribute to core stability and endurance. Load cells can be applied during suspension training to quantify the interaction between individuals and the exercise equipment.

Neuromuscular Consequences of Lumbopelvic Dysfunction: Research and Clinical Perspectives.

Injuries involving the lumbopelvic region (ie, lumbar spine, pelvis, hip) are common across the lifespan and include pathologies such as low back pain, femoroacetabular impingement syndrome, labrum tear, and osteoarthritis. Joint injury is known to result in an arthrogenic muscle response which contributes to muscle weakness and altered movement patterns. The purpose of this manuscript is to summarize the arthrogenic muscle response that occurs across lumbopelvic region pathologies, identify methods to quantify muscle function, and propose suggestions for future research. While each lumbopelvic region pathology is unique, there are a few common impairments and a relative consistent arthrogenic muscle response that occurs across the region. Hip muscle weakness and hip joint range of motion limitations occur with both lumbar spine and hip pathologies, and individuals with low back pain are known to demonstrate inhibition of the transversus abdominis and multifidus. Assessment of muscle inhibition is often limited to research laboratory settings, but dynamometers, ultrasound imaging, and electromyography offer clinical capacity to quantify muscle function and inform treatment pathways. Future studies should systematically determine the arthrogenic muscle response across multiple muscle groups and the timeline for changes in muscle function and determine whether disinhibitory modalities improve functional outcomes beyond traditional treatment approaches.

Muscle Activation in the Shoulder Girdle and Lumbopelvic-Hip Complex During Common Therapeutic Exercises.

CONTEXT: Lumbopelvic-hip complex (LPHC) exercises are used to increase stabilization within the human body. Torso-elevated side support (TESS), foot-elevated side support (FESS), prone bridge plank (PBP), and V-sit are common LPHC exercises. OBJECTIVE: To evaluate muscle activation in the shoulder girdle and LPHC during 4 LPHC exercises and evaluate the reasoning for termination. STUDY DESIGN: Cross-sectional study. SETTING: Laboratory. PATIENTS OR OTHER PARTICIPANTS: Seventeen healthy participants (12 males and 5 females; age: 21.47 [3.16] y, height: 179.73 [8.92] cm, mass: 76.89 [11.17] kg). MAIN OUTCOME MEASURES: Participants completed 2 repetitions of the TESS, FESS, PBP, and V-sit until failure. Surface electromyography of the middle deltoid, latissimus dorsi, middle trapezius, rectus abdominis, erector spinae, external oblique, and gluteus medius were recorded and normalized to maximum voluntary isometric contraction (MVIC). The duration of exercise and subjective reasoning for termination of exercise was completed following the 4 tasks. RESULTS: The TESS and PBP had significantly greater middle deltoid muscle activation (TESS: 55.66% [24.45%] MVIC and PBP: 42.63% [18.25%] MVIC) compared with the FESS (10.10% [10.04%] MVIC) and V-sit (2.21% [1.94%] MVIC), P < .05. The TESS produced significantly greater external oblique activity (78.13% [32.32%] MVIC) than the PBP (54.99% [19.54%] MVIC), P < .05. Due to shoulder fatigue and pain, 41.1% and 17.0% of participants terminated the TESS, respectively. The PBP was terminated due to abdominal fatigue (41.1%) and upper-extremity fatigue (47.0%). CONCLUSIONS: The V-sit resulted in isolated activity of the abdominal portion of the LPHC. The FESS had increased global co-contraction of the LPHC compared with the TESS. The PBP and TESS had significant muscle activation in the upper-extremity.

Feasibility of a Novel Video Game-Based Electromyography Biofeedback System in Patients With Knee Osteoarthritis.

CONTEXT: A novel virtual game system Knee Biofeedback Rehabilitation Interface for game-based home therapy (KneeBright) was developed for strength training using integrated electromyography biofeedback of the quadriceps muscle to control the game. The study aimed to compare the KneeBright and electromyography biofeedback interface among patients with knee osteoarthritis. DESIGN: Controlled before and after design. METHODS: Nineteen patients with knee osteoarthritis took part in this laboratory-based study. Exercise sessions took place on 2 separate days. During session 1, participants used a conventional electromyography biofeedback system while performing 3 sets of lower body exercises with emphasis on maximal muscle activation, endurance, and precision. During session 2, participants used the KneeBright game to match the exercise sets in the first session. For both sessions, knee extension torque during the isometric muscle activation exercises and time to voluntary additional exercise were recorded. Patient engagement was assessed using the technology acceptance model and System Usability Score questionnaires. RESULTS: The peak knee extension torque produced during the control exercise session and the KneeBright exercise session were positively correlated. Knee extension torque generated during KneeBright game exercise sessions was increased by an average of 25% compared to the control sessions (2.14 vs 1.77 N·m/kg, P = .02). The mean technology acceptance model score for the KneeBright system was 3.4/5 and the mean System Usability Score was 79, both indicating positive patient engagement. CONCLUSIONS: Patients using the KneeBright game produced greater knee torque than patients using the conventional system, had positive levels of engagement, and exercised longer with the KneeBright game.

Landing Stiffness Between Individuals With and Without a History of Low Back Pain.

CONTEXT: Reduced spinal stabilization, delayed onset of muscle activation, and increased knee joint stiffness have been reported in individuals with a history of low back pain (LBP). Biomechanical adaptations resulting from LBP may increase the risk for future injury due to suboptimal loading of the lower-extremity or lumbar spine. Assessing landing mechanics in these individuals could help identify which structures might be susceptible to future injury. OBJECTIVE: To compare vertical and joint stiffness of the lower-extremity and lumbar spine between individuals with and without a previous history of LBP. DESIGN: Cross-sectional study. SETTING: Research laboratory. PARTICIPANTS: There were 45 participants (24 without a previous history of LBP-age 23 [8] y, height 169.0 [8.5] cm, mass 69.8 [13.8] kg; 21 with a previous history of LBP-age 25[9] y, height 170.0 [8.0] cm, mass 70.2 [11.8] kg). INTERVENTIONS: Single-limb landing trials on the dominant and nondominant limb from a 30-cm box. MAIN OUTCOME MEASURES: Vertical stiffness and joint stiffness of the ankle, knee, hip, and lumbar spine. RESULTS: Individuals with a previous history of LBP had lower vertical stiffness (P = .04), but not joint stiffness measures compared with those without a previous history of LBP (P > .05). Overall females had lower vertical (P = .01), ankle (P = .02), and hip stiffness (P = .04) compared with males among all participants. Males with a previous history of LBP had lower vertical stiffness compared with males without a previous history LBP (P = .01). Among all individuals without a previous history of LBP, females had lower vertical (P < .01) and ankle stiffness measures (P = .04) compared with males. CONCLUSIONS: Landing stiffness may differ among males and females and a previous history of LBP. Comparisons between individuals with and without previous LBP should be considered when assessing landing strategies, and future research should focus on how LBP impacts landing mechanics.

Improvements in Lower-Extremity Function Following a Rehabilitation Program With Patterned Electrical Neuromuscular Stimulation in Females With Patellofemoral Pain: A Randomized Controlled Trial.

CONTEXT: Patellofemoral pain (PFP) is a challenging condition, with altered kinematics and muscle activity as 2 common impairments. Single applications of patterned electrical neuromuscular stimulation (PENS) have improved both kinematics and muscle activity in females with PFP; however, the use of PENS in conjunction with a rehabilitation program has not been evaluated. OBJECTIVE: To determine the effects of a 4-week rehabilitation program with PENS on lower-extremity biomechanics and electromyography (EMG) during a single-leg squat (SLS) and a step-down task (SDT) in individuals with PFP. STUDY DESIGN: Double-blinded randomized controlled trial. SETTING: Laboratory. Patients of Other Participants: Sixteen females with PFP (age 23.3 [4.9] y, mass 66.3 [13.5] kg, height 166.1 [5.9] cm). INTERVENTION: Patients completed a 4-week supervised rehabilitation program with or without PENS. MAIN OUTCOME MEASURES: Curve analyses for lower-extremity kinematics and EMG activity (gluteus maximus, gluteus medius, vastus medialis oblique, vastus lateralis, biceps femoris, and adductor longus) were constructed by plotting group means and 90% confidence intervals throughout 100% of each task, before and after the rehabilitation program. Mean differences (MDs) and SDs were calculated where statistical differences were identified. RESULTS: No differences at baseline in lower-extremity kinematics or EMG were found between groups. Following rehabilitation, the PENS group had significant reduction in hip adduction between 29% and 47% of the SLS (MD = 4.62° [3.85°]) and between 43% and 69% of the SDT (MD = 6.55° [0.77°]). Throughout the entire SDT, there was a decrease in trunk flexion in the PENS group (MD = 10.91° [1.73°]). A significant decrease in gluteus medius activity was seen during both the SLS (MD = 2.77 [3.58]) and SDT (MD = 4.36 [5.38]), and gluteus maximus during the SLS (MD = 1.49 [1.46]). No differences were seen in the Sham group lower-extremity kinematics for either task. CONCLUSION: Rehabilitation with PENS improved kinematics in both tasks and decreased EMG activity. This suggests that rehabilitation with PENS may improve muscle function during functional tasks.

Detection of Gluteal Changes Using Ultrasound Imaging During Phases of Gait in Individuals With Medial Knee Displacement.

Context: Medial knee displacement (MKD) is a common risk factor for lower-extremity injury and is related to altered gluteal muscle activity. Ultrasound imaging (USI) is a reliable means to explore mechanical muscle activity; however, no information exists regarding USI of the gluteals during gait in an MKD population. Objective: To determine differences in USI gluteal muscle activity during gait in individuals with and without MKD. Design: Descriptive laboratory study. Setting: University research laboratory. Participants: Out of 28 participants, 14 exhibiting MKD unilaterally during a single-leg squat (19.36 [1.51] y, 169.73 [7.50] cm, and 62.01 [10.57] kg; 10 females) and 14 matched non-MKD subjects (20.29 [1.73] y, 167.24 [9.07] cm, and 67.53 [16.03] kg). Interventions: Bilateral B-mode USI of the gluteus maximus (Gmax) and gluteus medius (Gmed) muscles during quiet stance, heel strike, and a 10-second treadmill walking clip. Main Outcome Measures: Gluteal thickness measures normalized to quiet stance yielded activity ratios, and percentage of muscle thickness change was assessed between heel strike and quiet stance. Differences between groups were assessed with Cohen's d effect sizes with 95% confidence intervals. Activity ratios with 90% confidence intervals plotted on 10% intervals from 0% to 100% of gait were used to compare groups and limbs. A subsample of images was measured to determine intertester reliability. Results: USI revealed decreased Gmax and Gmed percent change at heel strike (%change = -9.57% [7.15%] and -8.76% [4.26%], respectively). The MKD limb compared with the contralateral limb exhibited decreased Gmed activity ratio at 30% of gait (MKD = 0.89 [0.056]; non-MKD = 1.01 [.052]). Intertester reliability was excellent for gluteus maximus (intraclass correlation coefficient = .987 [.014]) and Gmed (intraclass correlation coefficient = .989 [.013]) measurements. Conclusions: USI highlighted gluteal activity differences of MKD limbs during gait, which may contribute to inadequate hip stabilization during this daily repetitive task. These findings potentiate the use of USI as an intervention- or screening-based visual tool.

Ultrasound Assessment of the Transverse Abdominis During Functional Movement.

OBJECTIVES: The traditional activation ratio divides contracted muscle thickness by resting muscle thickness while an abdominal draw-in maneuver is performed during hook lying. Ultrasound imaging during function, such as standing or gait, or peak knee flexion in a single-leg squat allows for further visualization of muscle activity. The goal of this study was to examine activation ratio calculations for transverse abdominis function in supine versus loaded conditions to determine the most informative normalization strategy for muscle activity based on thickness values. METHODS: Transverse abdominis thickness was measured via ultrasound in 35 healthy participants under 4 different conditions. Comparisons were made between the traditional activation ratio tabletop, standing activation ratio (standing abdominal draw-in maneuver thickness/quiet standing thickness), and functional activation ratio (single-leg squat thickness/quiet standing thickness). Additionally, a cued activation ratio (single-leg squat with cued abdominal draw-in maneuver thickness/single-leg squat thickness) during the single-leg squat was obtained. Activation ratios of greater than 1.0 indicated that participants could activate the muscle during activity, and values were compared by analysis of variance. RESULTS: The participants included 23 women and 12 men with a mean age ± SD of 21.3 ± 2.7 years, mass of 66.1 ± 14.4 kg, and height of 168.5 ± 10.1 cm. Activation ratios exceeded 1.0 in 94.3% for the traditional activation ratio, 85.7% for the standing activation ratio, 82.9% for the cued activation ratio, and 82.9% for the functional activation ratio. With groups defined as tabletop activated or not, the standing, cued, and functional activation ratios were all significantly different (all P < .05). CONCLUSIONS: Normalizing muscle thickness to the corresponding functional position quiet value provides a useful functional activation ratio and may help clinicians better understand the transverse abdominis role during complex functional tasks. Assessment techniques using various formulas for activation ratios reveal that the muscle functions differently during weight bearing compared to traditional measures.

Influence of unilateral versus bilateral patellofemoral pain on physical activity, pain self-efficacy, and disability.

BACKGROUND: Patellofemoral pain (PFP) affects physical and psychosocial health; however, it is unclear if unilateral and bilateral PFP induce similar levels of impairments. OBJECTIVES: We aimed to compare physical activity (PA), pain self-efficacy, and disability between individuals with unilateral and bilateral PFP, and to compare these groups against pain-free controls. DESIGN: Cross-sectional case-control. METHOD: Sixty-two individuals with PFP (25 unilateral and 37 bilateral) and 20 pain-free controls completed the PA assessment using an accelerometer by daily steps, light PA, and moderate-to-vigorous PA (MVPA). We also calculated variability in each PA variable. Pain self-efficacy and disability were measured using the Pain Self-Efficacy Questionnaire and Anterior Knee Pain Scale, respectively. RESULTS: Individuals with bilateral PFP took fewer daily steps compared to pain-free controls (9568.1 ± 3827.0 vs. 12,285.8 ± 2821.2 steps/day; P = 0.018, Cohen d = 0.79), whereas individuals with unilateral PFP did not (11,099.2 ± 3547.1 steps/day; P = 0.503, Cohen d = 0.37). Individuals with bilateral PFP showed greater variability in MVPA compared to individuals with unilateral PFP (42.9 ± 23.1 vs. 29.0 ± 15.9; P = 0.011, Cohen d = 0.91) and pain-free controls (42.9 ± 23.1 vs. 17.6 ± 6.1; P < 0.001, Cohen d = 1.21). Individuals with unilateral and bilateral PFP similarly exhibited less time spent in MVPA, greater variability in daily steps, lower pain self-efficacy, and greater disability compared to pain-free controls (P < 0.001, Cohen d = 1.14-3.89). CONCLUSIONS: Versus pain-free controls, individuals with bilateral PFP displayed greater variability in MVPA than individuals with unilateral PFP. However, it is important to note that unilateral PFP influenced time spent in MVPA, variability in daily steps, pain self-efficacy, and disability at similar levels to bilateral PFP.

Suggestions and Considerations for Application of Movement Screens to Clinical Practice.

Pre-participation and return to activity functional assessments are commonly used in clinical practice to assess movement quality and identify athletes' limitations. While there are slight differences between each specific test battery, general guidelines suggest that the tests be completed without a warm-up. This has been suggested because dynamic stretching may improve range of motion and athletic performance. However, athletes typically warm up prior to participating in sport. Therefore, researchers should investigate the acute effects of dynamic stretching on functional tests and movement screens and evaluate other factors that may influence performance on these test batteries. Scientific evidence for standardized implementation of various movement screens is lacking, and future research should aim to identify gaps in the literature to allow clinicians to properly implement evidence-based practice functional assessments. The purpose of this commentary is to discuss various considerations for implementing movement screens and assessment tools into clinical practice. LEVEL OF EVIDENCE: 5.

Gamified delivery of at-home rehabilitation for individuals with nonspecific low back pain: a randomized controlled trial.

PURPOSE: To measure the change in pain and disability during and after a 6-week gamified delivery of home exercise compared to a take-home packet. MATERIALS AND METHODS: A 6-week at-home exercise protocol included participants randomly allocated to a gamified delivery group or packet group. The exercise protocol included the plank, side plank, foot elevated side plank, dead bug, and bird dog completed until discontinuation. The gamified delivery group received on-demand exercise videos and weekly exercise duration leaderboards. The packet group received a take-home packet. RESULTS: Forty participants were randomized into a packet group and leaderboard group, and 30 participants completed the study. Disability was significantly lower at 6-weeks (11.29 ± 9.81%) compared to baseline (15.93 ± 11.65%) in the packet group (χ2(2) =10.89, Z= -3.163, p=.002, r=.708). Percent disability was significantly lower at 6-weeks (8.00 ± 5.91%) compared to baseline (13.01 ± 7.17%) in the gamified delivery group (χ2(2) =13.235, Z= -3.399, p= <.001, r= -0.760). Worst pain was higher at baseline (7.05 ± 1.61%) than at 6-weeks (5.75 ± 1.68%) in the packet group (χ2(2) =8.067, Z = 2.760, p=.006, r= -0.617). Worst pain was higher at baseline (6.90 ± 1.33%) than at 6-weeks (5.24 ± 2.38%) in the gamified delivery group (χ2(2) =6.250, Z= -2.810, p=.005, r= -0.628). No significant difference in the change of disability from baseline to 6 weeks was found between groups (p=.483). CONCLUSIONS: Core exercises completed until failure may improve disability and pain at 6-weeks and positively influence perceived patient improvement.Registry: Clinicaltrials.gov; Registration number: NCT05573932.

Nonspecific low back pain affects individuals on a personal, societal and economic level.Both interventions and exercises in this study influenced disability and pain, the outcome variables most important to individuals suffering from nonspecific low back pain.Targeting core musculature during at-home exercise may decrease pain and disability in the nonspecific low back pain population.

Balance Error Scoring System Performance Differences in Figure Skaters Based on Discipline.

Background: Balance and postural stability are required of figure skaters throughout on-ice performance. Spinning, jumping, and landing each rely on this skill set to maintain control while skaters manage changing demands for each skating discipline. Hypothesis/Purpose: The aim of this study was to compare balance error scoring system (BESS) performance in figure skaters between disciplines and determine if age was related to BESS performance. Study Design: Cross-sectional study. Methods: Three hundred and fifty-eight figure skaters (age: 15.4±3.3 years, 213 females, 145 males) of multiple disciplines completed the BESS during the United States Figure Skating's Standardized Testing of Athleticism to Recognize Skaters (S.T.A.R.S.) combine. Errors during each condition of the BESS were recorded by trained evaluators. A 3x6 ANOVA was used to determine BESS differences based on skating discipline. Spearman's rho (ρ) correlation coefficients were calculated for relationships between BESS errors and age. Results: Ice dancers had more errors than singles and pairs for bipedal foam (p<0.001) but had fewer errors than single skaters for single leg foam (p=0.002). Tandem on a firm surface also showed an increase in errors for ice dancers and pairs skaters compared to singles (p<0.001). There were significant weak negative relationships noted between age and bipedal foam and single leg firm conditions (ρ=-0.14, -0.23, p<0.05). Conclusion: Figure skaters of different disciplines have varying levels of static postural stability. Assessing postural stability in figure skaters can provide insight to improve performance and may identify skaters at risk of injury. Level of Evidence: 3©The Author(s).

Optimizing normalization methods of the external oblique: A cross-sectional study.

BACKGROUND: Adequate normalization methodology to establish maximum voluntary isometric contraction (MVIC) is needed to compare %MVIC values for core exercise completed until discontinuation. Clinicians can use %MVIC classifications to guide their preventative and rehabilitative exercise interventions. OBJECTIVE: The aim of this study was to compare %MVIC of the external oblique (EO) between normalization techniques of side-lying lateral trunk flexion and Roman chair lateral trunk flexion. METHODS: Twenty-two participants completed two MVIC techniques followed by one repetition of the prone bridge plank (PBP), torso elevated side plank (TESP), foot elevated side plank (FESP), dead bug and bird dog. The average %MVIC during the first 5-seconds, last 5-seconds and overall duration of exercise were included for analysis. ANOVA was used to compare normalized %MVIC from each of the 5 exercises between MVIC techniques. Alpha set a priori p= 0.05. RESULTS: The side-lying table technique yielded no %MVIC values above 100%, while the Roman chair technique produced 7 values above 100%. The largest mean difference between techniques was during the last 5-seconds of the torso elevated side plank (57.87 ± 38.51%MVIC, p< 0.001). CONCLUSION: The side-lying table technique likely provides the optimal methodology of %MVIC determination.

Strength Training Rehabilitation Incorporating Power Exercises (STRIPE) for individuals with patellofemoral pain: a randomised controlled trial protocol.

Patellofemoral pain (PFP) is a chronic condition that presents with patellar pain during various daily and recreational activities. Individuals with PFP have a wide range of impairments that result in long-term disability and reduced quality of life. Current interventions target hip muscle weakness with strength-based exercises, but recurrence rates are as high as 90%. A single feasibility study demonstrated success with power-based exercises; however, there is limited evidence evaluating pain or self-reported function in larger cohorts, and no study has assessed recurrence rates. This protocol details a study evaluating a strength-based rehabilitation programme compared with a strength-based programme incorporating power-based exercises in individuals with PFP. This single-blinded randomised controlled trial will evaluate 88 participants with PFP, aged 18-40 years old. Participants will be recruited from three universities, the surrounding community and sports medicine clinics. Participants will receive three telemedicine rehabilitation sessions a week for 6 weeks. The rehabilitation programme will consist of either strength-based exercises or a combination of power and strength-based exercises. Pain, subjective function and recurrence rates will be assessed at baseline, immediately after the intervention and at four follow-up time points: 6-month, 12-month, 18-month and 24-month postintervention. We will also assess neuromuscular function of the hips and global rating of change at each postintervention time point. Trial registration number NCT05403944.

Providing Visual Biofeedback Using Brightness Mode Ultrasound During a Golf Swing.

Using ultrasound biofeedback in conjunction with verbal cueing can increase muscle thickness more than verbal cueing alone and may augment traditional rehabilitation techniques in an athletic, physically active population. Brightness mode (B-mode) ultrasound can be applied using frame-by-frame analysis synchronized with video to understand muscle thickness changes during these dynamic tasks. Visual biofeedback with ultrasound has been established in static positions for the muscles of the lateral abdominal wall. However, by securing the transducer to the abdomen using an elastic belt and foam block, biofeedback can be applied during more specific tasks prevalent in lifetime sports, such as golf. To analyze muscle activity during a golf swing, muscle thickness changes can be compared. The thickness must increase throughout the task, indicating that the muscle is more active. This methodology allows clinicians to immediately replay ultrasound videos for patients as a visual tool to instruct proper activity of the muscles of interest. For example, ultrasound can be used to target the external and internal obliques, which play an important role in swinging a golf club or any other rotational sport or activity. This methodology aims to increase oblique muscle thickness during the golf swing. Additionally, the timing of muscle contraction can be targeted by instructing the patient to contract the abdominal muscles at specific time points, such as the beginning of the downswing, with the goal of improving muscle firing patterns during tasks.

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise.

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured between fascial borders at a given time point during an exercise. This selected time point produces a one-dimensional image resulting in real-time, live observation of anatomy. Ultrasound used during functional movement can be referred to as dynamic ultrasound; this is feasible and reliable with the use of a linear transducer, elastic belt, and foam block to secure consistent transducer placement. The lateral abdominal wall is commonly investigated using ultrasound due to the overlapping nature of the muscles. Surface electromyography (sEMG) can complement M-mode ultrasound imaging because it measures the electrical representation of muscle activation. There is minimal evidence using M-mode ultrasound and sEMG simultaneously during core exercise. Exercises that challenge the core musculature involve both isometric holds (e.g., side plank), as well as oscillatory extremity movements (e.g., dead bug). In this study, both instruments will be used simultaneously to measure core muscle function during exercise. Ultrasound measurements will be obtained using a linear transducer and ultrasound unit, and sEMG measurements will be acquired from a wireless sEMG system. To make comparisons between participants and exercises, normalization methods using static, exercise starting positions for both instruments will be used. An activation ratio will be used for ultrasound and calculated by dividing the contracted thickness (thickness during a time point of exercise) by the rested (starting position) thickness. Muscle thickness will be measured in centimeters from the superior inferior fascial border to inferior superior fascial border. These methods aim to offer an innovative and practical measurement of muscle function with M-mode ultrasound and sEMG during core endurance exercises.