How Changing the Inversion/ Eversion Foot Angle Affects the Nondriving Intersegmental Knee Moments and the Relative Activation of the Vastii Muscles in Cycling

Nondriving intersegmental knee moment components (i.e., varus/valgus and internal/ external axial moments) neutral). A previously described mathematical model was used to compute the nondriving intersegmental knee moments throughout the crank cycle. The excitations of the VMO, VL, and TFL muscles were measured with surface electromyography and the muscle activations were computed. On average, the 10-deg everted position decreased the peak varus moment by 55% and decreased the peak internal axial moment by 53% during the power stroke (crank cycle region where the knee moment is extensor). A correlation analysis revealed that the VMO/VL activation ratio increase

Gluteal Muscle Activation During Common Yoga Poses

# Background Approximately 24% of physical therapists report regularly using yoga to strengthen major muscle groups. Although clinicians and athletes often use yoga as a form of strength training, little is known about the activation of specific muscle groups during yoga poses, including the gluteus maximus and medius. # Hypothesis/Purpose The purpose of this study was to measure gluteus maximimus and gluteus medius activation via electromyography (EMG) during five common yoga poses. A secondary purpose of the current study was to examine differences in muscle activation between sexes and experience levels. # Study Design Cross-Sectional # Methods Thirty-one healthy males and females aged 18-35 years were tested during five yoga poses performed in a randomized order. Surface EMG electrodes were placed on subjects’ right gluteus maximus and gluteus medius. Subjects performed the poses on both sides following a maximal voluntary isometric contraction (MVIC) test for each muscle. All yoga pose EMG data were normalized to the corresponding muscle MVIC data. # Results Highest gluteus maximus activation occurred during Half Moon Pose on the lifted/back leg (63.3% MVIC), followed by the stance/front leg during Half Moon Pose (61.7%), then the lifted/back leg during Warrior Three Pose (46.1%). Highest gluteus medius activation occurred during Half Moon Pose on the lifted/back leg (41.9%), followed by the lifted/back leg during the Warrior Three Pose (41.6%). A significant difference was found in %MVIC of gluteus medius activity between male and female subjects (p = 0.026), and between experienced and inexperienced subjects (p = 0.050), indicating higher activation among males and inexperienced subjects, respectively. # Conclusion Half Moon Pose and Warrior Three Pose elicited the highest activation for both the gluteus maximus and the gluteus medius. Higher gluteus medius activation was seen in males and inexperienced subjects compared to their female and experienced counterparts. # Level of Evidence

Modeling of Human-Exoskeleton Alignment and Its Effect on the Elbow Flexor and Extensor Muscles during Rehabilitation

Human-exoskeleton misalignment could lead to permanent damages upon the targeted limb with long-term use in rehabilitation. Hence, achieving proper alignment is necessary to ensure patient safety and an effective rehabilitative journey. In this study, a joint-based and task-based exoskeleton for upper limb rehabilitation were modeled and assessed. The assessment examined and quantified the misalignment present at the elbow joint as well as its effects on the main flexor and extensor muscles’ tendon length during elbow flexion-extension. The effects of the misalignments found for both exoskeletons resulted to be minimal in most muscles observed, except the anconeus and brachialis. The anconeus muscle demonstrated a relatively higher variation in tendon length with the joint-based exoskeleton misalignment, indicating that the task-based exoskeleton is favored for tasks that involve this particular muscle. Moreover, the brachialis demonstrated a significantly higher variation with the task-based exoskeleton misalignment, indicating that the joint-based exoskeleton is favored for tasks that involve the muscle

Dwarf galaxies J-factors without priors: a frequentist Jeans analysis consistent with indirect Dark Matter searches

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Shoulder Kinematics Assessment towards Exoskeleton Development

Neuromuscular and sensorimotor degeneration caused by stroke or any other disease significantly reduce the physical, cognitive, and social well-being across the life span. Mostly, therapeutic interventions are employed in order to restore the lost degrees-of-freedom (DOF) caused by such impairments and automating these therapeutic tasks through exoskeletons/robots is becoming a common practice. However, aligning these robotic devices with the complex anatomical and geometrical motions of the joints is very challenging. At the same time, a good alignment is required in order to establish a better synergy of human-exoskeleton system for an effective intervention procedure. In this paper, a case study of an exoskeleton and shoulder joint alignment were studied through different size and orientation impairment models through motion capture data and musculoskeletal modeling in OpenSim. A preliminary result indicates that shoulder elevation is very sensitive to misalignment and varies with shoulder joint axes orientation; this is partly due to drastic displacement of the upper arm axes with respect to the shoulder joint origin during elevation. Additional study and analysis is required to learn any possible restraint on shoulder elevation that could potentially help in the exoskeleton development

Comparison of the SWAY Balance Mobile Application to the Abbreviated Balance Error Scoring System

The SWAY Balance Mobile Application (SWAY Medical, LLC, Tulsa, OK) is a new method for quantifiably assessing balance in both clinical and on-field environments. The purpose of this study was to compare the accelerometer-based SWAY balance assessment to the commonly used and observation-based Abbreviated Balance Error Scoring System (BESS) balance assessment. Forty-four participants (22 male; mean age: 19.59 ± 1.23 years) completed the SWAY Balance Mobile Application protocol while the Abbreviated BESS was simultaneously scored. Bivariate linear regression was performed and correlation co-efficient calculated to determine the degree of correlation between the SWAY and Abbreviated BESS scores. The mean Abbreviated BESS score was 5.93 ± 4.45 and the mean SWAY score was 81.79 ± 14.06. A significant negative correlation was found between the two balance measures (r = −0.601, P \u3c .0001). The SWAY balance assessment may provide for a means to quantifiably assess balance in an objective manner, thereby eliminating subjective bias in balance assessments