Shoulder Muscle Activation Levels During the Push-Up-Plus Exercise on Stable and Unstable Surfaces.

The aim of this study was to evaluate the acute effect of the use of stable and unstable surfaces on electromyography (EMG) activity and coactivation of the scapular and upper-limb muscles during the push-up plus (with full protraction of the scapula). Muscle activation of anterior deltoid (AD), posterior deltoid (PD), pectoralis major, biceps brachii (BB), triceps brachii (TB), upper trapezius (UT), middle trapezius (MT), lower trapezius (LT), and serratus anterior (SA) levels and coactivation index were determined by surface EMG in 20 young men during push-up plus performed on a stable and unstable condition (2 unstable devices applied to hands and feet). The paired t test and Cohen d were used for statistical analysis. The results showed that during the execution of the push-up plus on the unstable surface an increased EMG activity of the scapular stabilizing muscles (SA, MT, and LT) was observed, while AD and PD muscles showed a decrease. During exercise execution on the unstable surface there was a higher index of coactivation of the scapular muscles (SA-MT and UT-LT pairs). No significant differences were observed in TB-BB and AD-PD pairs. These results suggest that the push-up-plus exercise associated with unstable surfaces produced greater EMG activity levels and coactivation index of the scapular stabilizing muscle. On the other hand, the use of an unstable surface does not promote the same effect for the shoulder muscles.

Associations between dual-task walking and cognitive impairment in people attending a cognitive diagnostic clinic.

OBJECTIVES: Dual-task walking performance is an early marker of dementia. However, there is uncertainty about which measure of the dual-task test is a better marker. The objective of this study was to determine which dual-task measure best differentiates between normal cognition, mild cognitive impairment (MCI) and dementia. METHODS: Participants (n = 116) were aged ≥60 years attending a cognitive clinic in Melbourne, Australia. Single- and dual-task gait speed were obtained using a 16 metre distance and stopwatch. The cognitive task involved reciting alternate letters of the alphabet sitting and walking. Dual-task interference in gait and cognition was calculated as: single-task-dual-task/single task × 100 and summed to obtain total interference. Multiple linear regression was used to determine differences in single and dual-task measures between those with no cognitive impairment (n = 11), MCI (n = 54) and dementia (n = 51). RESULTS: The mean age of the sample was 76.9 (SD 6.4) years and 48.3% (n = 56) were female. Compared to those with dementia: (a) those with MCI had a higher dual-task letter rate and lower cognitive and total interference (all indicate better performance) (p < .05) and (b) those with no cognitive impairment had a higher single- and dual-task letter rate (both indicate better performance) (p < .05). There were no differences between those with no cognitive impairment and those with MCI (all p > .05). CONCLUSIONS: In a cognitive clinic, measurement during dual-task walking differentiated those with dementia from those with MCI or no cognitive impairment. However, differences appear to be driven by performance on the cognitive, rather than the gait task.

Effects of intensive arm training with an electromechanical orthosis in chronic stroke patients: a preliminary study.

OBJECTIVES: To evaluate the use of an electromechanical device, comprising an exoskeleton, a static orthosis, and a glove, for functional rehabilitation of the elbow and hand in patients with hemiparesis, and to compare it with physical therapy rehabilitation. DESIGN: Pretest-posttest design. SETTING: Rehabilitation laboratory. PARTICIPANTS: Volunteer sample of persons (N=12) with persistent hemiparesis from a single, unilateral stroke within the past 3 to 36 months. INTERVENTIONS: The volunteers were randomly divided into 2 groups. One group was treated with a conventional program of physiotherapy, and another group participated in a training program in which an electromechanical orthosis was used. All volunteers received 24 sessions, held 3 times a week for 8 weeks. MAIN OUTCOME MEASURES: Modified Ashworth Scale (MAS), Fugl-Meyer Assessment (FMA), and electromyogram (EMG) amplitude. RESULTS: No statistical difference was found in the initial and final values of the MAS. Both groups showed a significant increase for the total scores of the FMA. However, only the group treated with the orthosis showed an increase in FMA scores related to the wrist and hand joint. The EMG analysis showed increased EMG amplitudes for all muscles in the group treated with the orthosis, whereas the group treated with physiotherapy showed gains in electromyographic activity only in the extensor digitorum communis. Intergroup comparison showed that the initial FMA scores of the wrist/hand were higher in the group treated with physiotherapy. However, after training, the scores in the group that used the orthosis were equivalent to those of the physiotherapy group. CONCLUSIONS: The results suggest that this device can be an auxiliary tool to help the conventional rehabilitation program of motor function of the affected upper extremity.

TEST-RETEST RELIABILITY OF THE CLOSED KINETIC CHAIN UPPER EXTREMITY STABILITY TEST (CKCUEST) IN ADOLESCENTS: RELIABILITY OF CKCUEST IN ADOLESCENTS.

BACKGROUND: The Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST) has been proposed as an option to assess upper limb function and stability; however, there are few studies that support the use of this test in adolescents. PURPOSE: The purpose of the present study was to investigate the intersession reliability and agreement of three CKCUEST scores in adolescents and establish clinimetric values for this test. STUDY DESIGN: Test-retest reliability. METHODS: Twenty-five healthy adolescents of both sexes were evaluated. The subjects performed two CKCUEST with an interval of one week between the tests. An intraclass correlation coefficient (ICC3,3) two-way mixed model with a 95% interval of confidence was utilized to determine intersession reliability. A Bland-Altman graph was plotted to analyze the agreement between assessments. The presence of systematic error was evaluated by a one-sample t test. The difference between the evaluation and reevaluation was observed using a paired-sample t test. The level of significance was set at 0.05. Standard error of measurements and minimum detectable changes were calculated. RESULTS: The intersession reliability of the average touches score, normalized score, and power score were 0.68, 0.68 and 0.87, the standard error of measurement were 2.17, 1.35 and 6.49, and the minimal detectable change was 6.01, 3.74 and 17.98, respectively. The presence of systematic error (p < 0.014), the significant difference between the measurements (p < 0.05), and the analysis of the Bland-Altman graph infer that CKCUEST is a discordant test with moderate to excellent reliability when used with adolescents. CONCLUSION: The CKCUEST is a measurement with moderate to excellent reliability for adolescents. LEVEL OF EVIDENCE: 2b.

Activation of selected shoulder muscles during unilateral wall and bench press tasks under submaximal isometric effort.

STUDY DESIGN: Controlled laboratory study. OBJECTIVE: To assess the activation of 7 shoulder muscles under 2 closed kinetic chain (CKC) tasks for the upper extremity using submaximal isometric effort, thus providing relative quantification of muscular isometric effort for these muscles across the CKC exercises, which may be applied to rehabilitation protocols for individuals with shoulder weakness. BACKGROUND: CKC exercises favor joint congruence, reduce shear load, and promote joint dynamic stability. Additionally, knowledge about glenohumeral and periscapular muscle activity elicited during CKC exercises may help clinicians to design protocols for shoulder rehabilitation. METHODS: Using surface electromyography, activation level was measured across 7 shoulder muscles in 20 healthy males, during the performance of a submaximal isometric wall press and bench press. Signals were normalized to the maximal voluntary isometric contraction, and, using paired t tests, data were analyzed between the exercises for each muscle. RESULTS: Compared to the wall press, the bench press elicited higher activity for most muscles, except for the upper trapezius. Levels of activity were usually low but were above 20% maximal voluntary isometric contraction for the serratus anterior on both tasks, and for the long head triceps brachii on the bench press. CONCLUSIONS: Both the bench press and wall press, as performed in this study, led to relatively low EMG activation levels for the muscles measured and may be considered for use in the early phases of rehabilitation.