Electromyographic comparison of conventional machine strength training versus bodyweight exercises in patients with chronic stroke.

OBJECTIVE: To investigate whether bodyweight exercises can induce comparable levels of muscle activity as conventional machine exercises in chronic stroke patients. METHODS: Eighteen patients performed three repetitions of bilateral- and unilateral machine leg press and the bodyweight exercises chair rise and hip thrust. Surface electromyography (EMG) was recorded from 10 lower extremity muscles and normalized to maximal EMG (nEMG) of the non-paretic leg. RESULTS: For the paretic leg, the bodyweight exercises showed comparable levels of nEMG in 6 out of 10 muscles compared with the bilateral leg press. Vastus lateralis nEMG was higher during bilateral leg press compared with hip thrust (38% [95% CI 33-42] vs. 10% [95% CI 6-15], p < 0.0001) and chair rise (38% [95% CI 33-42] vs. 27% [95% CI 22-32], p < 0.0001). Vastus medialis nEMG was higher during bilateral leg press compared with hip thrust (34% [95%CI 27-40] vs. 8% [95% CI 2-15], p < 0.0001). Unilateral leg press showed higher nEMG compared with bilateral leg press in biceps femoris (28% [95% CI 23-34] vs. 19% [95% CI 13-24], p = 0.0009), gluteus maximus (32% [95% CI 23-41] vs. 25% [95% CI 16-34], p < 0.05), and vastus medialis (42% [95% CI 36-48] vs. 34% [95% CI 27-40], p = 0.0013). DISCUSSION: In patients with chronic stroke, bodyweight exercises activate the majority of the lower limb muscles to comparable levels as bilateral leg press performed in machine. In addition, unilateral leg press was superior to the bilateral leg press and both bodyweight exercises.

Effects of high-intensity physical training on muscle fiber characteristics in poststroke patients.

INTRODUCTION: Stroke is a leading cause of disability worldwide. High-intensity physical training can improve muscle strength and gait speed, but adaptive mechanisms at the muscle cellular level are largely unknown. METHODS: Outpatients with poststroke hemiparesis participated in a 3-month rehabilitation program combining high-intensity strength and body-weight supported treadmill-training. Biopsies sampled bilaterally from vastus lateralis muscles, before, after, and at 1-year follow-up after intervention, were analyzed for fiber size, type, and capillarization. RESULTS: At baseline, paretic lower limbs had smaller muscle fiber size and lower type I and IIA and higher type IIX percentages than nonparetic lower limbs. Paretic lower limbs had increased type IIA fibers after training. At follow-up, no difference between the lower limbs remained. CONCLUSIONS: Although high-intensity training appeared not to induce changes in fiber size or capillarization, increased type IIA fiber percentages may contribute to muscle power and endurance, which is crucial for functional capacity. Muscle Nerve 56: 954-962, 2017.

Action research in rehabilitation with chronic stroke recovery: A case report with a focus on neural plasticity.

BACKGROUND: Chronic stroke patients are primarily referred to general rehabilitation, rather than to specific neurorehabilitation. Currently, there are no Danish clinical guidelines for chronic stroke, but recent research in neuroplasticity has contributed to possible rehabilitation interventions for these patients. OBJECTIVE: The purpose of this project is to describe the use of a specialized neuroplastic approach in combination with an already existing training program. METHODS: The project is designed as an action research project concerning four participants with chronic stroke. Through ten intervention, a neuroplastic focus has been added to their group training program including daily home training. Participants were tested before and after the intervention with MAS, DGI, 6MWT, SSQLS. RESULTS: All four participants improved their functional levels and their quality of life following the intervention. CONCLUSIONS: This report indicates that a specific neuroplastic focus in combination with action research has an impact on the participants with chronic stroke. However, there is still no clarity regarding what type of rehabilitation methods can be considered the most efficacious in promoting neuroplasticity. This case report serves as a pilot project for further studies of how to implement neuroplasticity in physical therapy.

Electromyographic Comparison of Elastic Resistance and Machine Exercises for High-Intensity Strength Training in Patients With Chronic Stroke.

OBJECTIVE: To investigate whether elastic resistance training can induce comparable levels of muscle activity as conventional machine training in patients with chronic stroke. DESIGN: Comparative study. SETTING: Outpatient rehabilitation facility. PARTICIPANTS: Stroke patients (N=18) with hemiparesis (mean age, 57 ± 8y). INTERVENTIONS: Patients performed 3 consecutive repetitions at 10 repetition maximum of unilateral knee extension and flexion using elastic resistance and conventional machine training. MAIN OUTCOME MEASURES: Surface electromyography was measured in vastus lateralis, vastus medialis, biceps femoris, and semitendinosus and was normalized to maximal electromyography (% of max) of the nonparetic leg. RESULTS: In the paretic leg, agonist muscle activity ranged from 18% to 24% normalized electromyography (% of max) (nEMG) during knee flexion and from 32% to 40% nEMG during knee extension. For knee extension, vastus lateralis nEMG was higher during machine exercise than during elastic resistance exercise (40% [95% confidence interval {CI}, 33-47] vs 32% [95% CI, 25-39]; P=.003). In the nonparetic leg, agonist muscle activity ranged from 54% to 61% during knee flexion and from 52% to 68% during knee extension. For knee flexion semitendinosus nEMG was higher (61% [95% CI, 50-71] vs 54% [95% CI, 44-64]; P=.016) and for knee extension vastus medialis nEMG was higher (68% [95% CI, 60-76] vs 56% [95% CI, 48-64]; P<.001) during machine exercise than during elastic resistance exercise. By contrast, antagonist coactivation was significantly higher during knee flexion when performed using elastic resistance compared with the machine. Lastly, there were no differences in perceived exertion between exercise modalities. CONCLUSIONS: Machine training appears to induce slightly higher levels of muscle activity in some of the investigated muscles compared to elastic resistance during lower limb strength training in patients with chronic stroke. The higher level of coactivation during knee flexion when performed using elastic resistance suggests that elastic resistance exercises are more difficult to perform. This is likely due to a higher level of movement instability.

Effects of intensive physical rehabilitation on neuromuscular adaptations in adults with poststroke hemiparesis.

Hemiparesis-disability and muscle weakness of 1 side of the body-is a common consequence of stroke. High-intensity strength training may be beneficial to regain function, but strength coaches in the field of rehabilitation need evidence-based guidelines. The purpose of this study was to evaluate the effect of intensive physical rehabilitation on neuromuscular and functional adaptations in outpatients suffering from hemiparesis after stroke. A within-subject repeated-measures design with the paretic leg as the experimental leg and the nonparetic leg as the control leg was used. Eleven outpatients with hemiparesis after stroke participated in 12 weeks of intensive physical rehabilitation comprising unilateral high-intensity strength training with near-maximal loads (4-12 repetition maximum) and body weight supported treadmill training. At baseline and 12-week follow-up, the patients went through testing consisting of isokinetic muscle strength, neuromuscular activation measured with electromyography (EMG), electrically evoked muscle twitch contractile properties, and gait performance (10-m Walk Test and 6-min Walk Test). After the 12-week conditioning program, knee extensor and flexor strength increased during all contraction modes and velocities in the paretic leg. Significant increases were observed for agonist EMG amplitude at slow concentric and slow eccentric contraction. Twitch torque increased, whereas twitch time-to-peak tension remained unchanged. By contrast, no significant changes were observed in the nonparetic control leg. Gait performance increased 52-68%. In conclusion, intensive physical rehabilitation after stroke leads to clinically relevant neuromuscular improvements, leading to increased voluntary strength during a wide range of contraction modes and velocities, and improved gait velocity. Strength training coaches working in the field of rehabilitation can use this knowledge to safely and efficiently add high-intensity strength training to existing rehabilitation paradigms.

Effect of intensive outpatient physical training on gait performance and cardiovascular health in people with hemiparesis after stroke.

BACKGROUND: Stroke can result in severe motor deficits, and many people who have survived a stroke have poor cardiovascular fitness, with potentially disabling effects on daily life. OBJECTIVE: The objective of this study was to evaluate the impact of intensive physical training on gait performance and cardiovascular health parameters in people with stroke in the chronic stage. DESIGN: This was a single-group, pretest-posttest experimental study. METHODS: Fourteen people with hemiparesis after cerebrovascular injury (mean age=58.4 years, mean time since injury=25 months) participated in a 12-week training intervention, 5 times per week for 1.5 hours per session. The intervention consisted of high-intensity, body-weight-supported treadmill training; progressive resistance strength training; and aerobic exercise. The main outcome measures were gait performance (Six-Minute Walk Test, 10-Meter Walk Test, and aerobic capacity) and parameters of cardiovascular health (systolic and diastolic blood pressures, body mass index, and resting heart rate). RESULTS: Significant improvements in all main outcome parameters were observed in response to the intervention. Gait speed during the Six-Minute Walk Test increased 62%, and systolic and diastolic blood pressures decreased 10% and 11%, respectively. Weekly testing of walking speed showed that most of the increase in the walking speed occurred in the first 8 weeks of training. Correlation analyses showed that improvements were unrelated to age, chronicity, or level of functioning. CONCLUSIONS: High-intensity physical training for people with stroke in the chronic stage increased walking speed regardless of chronicity, age, or level of functioning. Further studies should investigate the intervention duration needed to reach the full potential of gait recovery.

Patient compliance in brain injury rehabilitation in relation to awareness and cognitive and physical improvement.

UNLABELLED: The purpose of the present study was to investigate the relationship between patients' compliance and awareness and outcome of brain injury rehabilitation. Subjects were 98 patients who underwent a holistic neuropsychological outpatient rehabilitation programme. Patients had suffered a traumatic brain injury (n = 26), a cerebrovascular accident (n = 58), or another neurological insult (n = 14). MEASURES: Two staff members, a neuropsychologist and a physiotherapist, retrospectively and separately rated patients' awareness and their compliance. Outcome was measured with the d2 test of concentration, measures of oxygen uptake, strength endurance, running speed, and patients' and relatives' ratings of patients' cognitive, physical, and overall problems on the European Brain Injury Questionnaire (EBIQ). The discrepancy between patients' and relatives' ratings on the EBIQ was incorporated as a second measure of patients' awareness. RESULTS: The neuropsychologist's compliance ratings were significantly related to measures of insight, improvement of d2 performance accuracy and stability, improvement of oxygen uptake, and reduction of cognitive and overall problems as reported by the patients, while the physiotherapist's compliance ratings were related to measures of insight, improvement of d2 performance speed, improvement of oxygen uptake and strength endurance, and all three EBIQ patient scales. DISCUSSION: The results suggest a differential relationship between situation-specific compliance and outcome.

Working alliance and patient compliance in brain injury rehabilitation and their relation to psychosocial outcome.

Employment and physical activity at follow up of 98 patients who underwent a holistic neuropsychological outpatient rehabilitation programme were examined in relation to therapeutic process factors. The patients had suffered a traumatic brain injury (n = 26), a cerebrovascular accident (n = 58) or another neurological insult (n = 14). Two staff members, a neuropsychologist and a physiotherapist, retrospectively rated patients' compliance with the therapeutic regime and their working alliances. They completed the ratings separately, but had some degree of common knowledge about the patients. While the compliance ratings were closely associated, working alliance ratings differed between the raters. The working alliance ratings were predictive of employment, but not physical activity. Both compliance ratings predicted physical training, but only the neuropsychologist's compliance rating was associated with follow-up employment. Post-hoc analysis showed that high compliance ratings given by the physiotherapist were also a predictor of employment. Overall, there was a tendency for the neuropsychologist's ratings to be more closely associated with employment than the physiotherapist's ratings. These results indicate that employment and physical activity are differentially predictable from different process measures rated from different professional perspectives.