Effect of pedaling exercise on the hemiplegic lower limb

The effects of cycling on walking outcomes in adults with stroke: a systematic review

BACKGROUND

Stationary cycling is often prescribed for survivors of stroke as a safe means of aerobic exercise to improve cardiovascular health. While cycling is typically not prescribed to restore ambulatory function, improvements in measures of walking after cycling interventions have been reported in the literature.

OBJECTIVE

To investigate the effects of cycling on walking outcomes in adults with stroke.

METHODS

Relevant databases were searched through 15 August. Walking-related outcomes were extracted. Correlation coefficients were computed to measure the relationship between exercise protocol parameters and change in walking outcomes.

RESULTS

Eleven articles were included in the review. Eight studies representing nine cycling intervention groups reported change in walking capacity measured by the six-minute walk test with improvements ranging from 6.1 to 63.0 m. Seven studies measured gait velocity, reporting improvements ranging from 0.01 to 0.21 m/sec. Protocols that yielded the greatest improvement in walking capacity prescribed moderate- to high-intensity aerobic training. Significant positive correlations were measured between change in gait velocity and number of exercise sessions and total minutes of exercise prescribed.

CONCLUSION

Considerable heterogeneity was observed across cycling protocols with respect to intensity, frequency, exercise duration and protocol duration. However, none of the studies reported declines in walking outcomes and improvements were measured in the absence of task-specific gait training. Cycling interventions employing moderate- to high-intensity aerobic training and 24 sessions or more may be optimal in improving gait velocity and walking capacity.

Usability of the novel ankle training equipment with spring resistance-based plantar press exercises in the standing position: A focus on chronic stroke patients with hemiplegic gait

BACKGROUND

To improve gait disability in patients with chronic stroke, ankle muscle strengthening and calf muscle stretching exercises are required. However, currently available ankle training equipment limit ankle exercises based on the position. Recently developed ankle training equipment enables spring resistance-based plantar press exercises to be performed in the standing position with weight support.

OBJECTIVE

To conduct a usability test of the ankle training equipment in the standing position by stroke patients with hemiplegic gait and verify its effects on ankle movements.

METHODS

The ankle training equipment was applied to five patients with chronic stroke and hemiplegic gait. In the standing position, the patients performed forefoot and rearfoot press exercises in the affected side with a day's interval at 20 repetitions maximum (RM). During the exercises, surface electromyography (sEMG) was used to measure the maximum voluntary isometric contraction (%MVIC) of the leg muscles. The System Usability Scale (SUS) was used to assess the ankle training equipment. Wilcoxon signed-rank test was used to evaluate the differences in muscle activity between the two exercises.

RESULTS

Forefoot and rearfoot press exercises increased the %MVIC in the biceps femoris. Additionally, the tibialis anterior and medial gastrocnemius activity was significantly different between the two exercises. The SUS was 78.75% (SD 12.7).

CONCLUSION

The usability test of the passive-control foot press trainer (PFPT) that with improvements in the structure and functions for convenience, it could be commercialized. PFPT could be an alternative to the ankle rehabilitation robot that necessitates a sitting position.

Increased Comfortable Gait Speed Is Associated With Improved Gait Biomechanics in Persons With Chronic Stroke Completing an 8-Week Forced-Rate Aerobic Cycling Intervention: A Preliminary Study

ABSTRACT

Task-specific gait training is recommended to improve locomotor function after stroke. Our objective was to determine the effects of a forced-rate aerobic exercise intervention on gait velocity and biomechanics in the absence of task-specific gait training. Individuals with chronic stroke ( N = 14) underwent 24 sessions of forced-rate aerobic exercise, at a targeted aerobic intensity of 60%-80% of their heart rate reserve. Change in comfortable walking speed in addition to spatiotemporal, kinematic, and kinetic variables were measured using three-dimensional motion capture. Overground walking capacity was measured by the 6-min walk test. To determine gait biomechanics associated with increased walking speed, spatiotemporal, kinematic, and kinetic variables were analyzed separately for those who met the minimal clinically important difference for change in gait velocity compared with those who did not. Participants demonstrated a significant increase in gait velocity from 0.61 to 0.70 m/sec ( P = 0.004) and 6-min walk test distance from 272.1 to 325.1 meters ( P < 0.001). Those who met the minimal clinically important difference for change in gait velocity demonstrated significantly greater improvements in spatiotemporal parameters ( P = 0.041), ground reaction forces ( P = 0.047), and power generation ( P = 0.007) compared with those who did not. Improvements in gait velocity were accompanied by normalization of gait biomechanics.

Cadence Feedback and Video-Based Engagement Improves Motivation and Performance during Pedalling in Stroke Patients

Video and music as a dissociative attention stimulus during exercise is known to distract from the discomfort of physical exertion and improve exercise adherence; however, the influence of video-based feedback and engagement during pedalling on the performance and motivation of pedalling in stroke patients is poorly understood. The aim of this study was to employ a novel video-based engagement paradigm for pedalling in stroke patients and evaluate its capacity to influence the cadence control, physiological output, and perceived motivation and enjoyment. Thirteen stroke patients were recruited with low-to-moderate lower-limb disability (mean age: 64.0 yrs.). A reference group of 18 healthy young adult subjects (mean age: 27.7 yrs.) was also recruited to assess the broad applicability of the techniques to a contrasting non-pathological cohort. The participants pedalled at a slow (60 RPM) and fast (100 RPM) target speed with constant resistance in 15 min pedalling bouts that included (i) baseline pedalling with real-time visual feedback of cadence deviation from the target provided only in the first 20 s (ii) real-time visual feedback of cadence data over the entire pedalling session, and (iii) real-time engagement to maintain the playback rate of a prerecorded video by pedalling at the target speed. During low speed pedalling, stroke patients demonstrated significantly smaller absolute cadence deviation during pedalling with feedback (mean difference: 1.8 RPM, p = 0.014) and video-based engagement (mean difference: 2.4 RPM, p = 0.006) compared to the baseline pedalling. For the healthy adults, feedback and video-based engagement reduced cadence deviation significantly at all speeds (p < 0.05). All but one stroke patient either enjoyed or really enjoyed the video engagement during pedalling and felt motivated to undertake this form of exercise in therapy in the future. This proof-of-concept study showed that feedback and video-based engagement may improve the targeted pedalling performance in stroke patients, and by helping dissociate subjects from physical cues associated with fatigue, may ultimately improve exercise motivation and compliance.

Leg Muscle Strength Correlates with Gait Performance in Advanced Parkinson Disease

Objective Leg muscle strength (LMS) is decreased in early-stage Parkinson disease (PD) patients and is associated with slower walking and falls. However, LMS in advanced PD has not been well investigated. The purpose of this study was to evaluate LMS in advanced PD patients and its effects on gait performance, activities of daily living, and the cognitive function. Methods The medical records of 132 patients with idiopathic advanced PD [Hoehn and Yahr (H&Y) stages 3 and 4] with a mean disease duration of 9.6 years were retrospectively reviewed. Leg extensor muscle strength of the patients was measured using a Strength Ergo 240. The associations between the LMS and gait performance, Barthel index, H&Y stage, and Mini-Mental State Examination (MMSE) score were analyzed. Results A Spearman's correlation analysis showed that LMS was correlated with the sex, age, age of disease onset, H&Y stage, Barthel index, MMSE score, and gait parameters. A multivariable linear regression analysis for identifying predictors of LMS showed that the gait velocity (β=0.377), Barthel index (β=0.281), sex (β=-0.187), and disease duration (β=-0.155) were significant. A receiver operating characteristic curve analysis for discriminating between H&Y stage 3 and 4 was performed for LMS; the area under the curve was 0.774 (95% confidence interval=0.696-0.851). Conclusions LMS was strongly associated with multiple domains of clinical characteristics, especially gait velocity and the Barthel index. Our study also suggested that LMS can be a predictor of PD progression.

Impact of Somatosensory Training on Neural and Functional Recovery of Lower Extremity in Patients with Chronic Stroke: A Single Blind Controlled Randomized Trial

Recovery of lower extremity (LE) function in chronic stroke patients is considered a barrier to community reintegration. An adequate training program is required to improve neural and functional performance of the affected LE in chronic stroke patients. The current study aimed to evaluate the effect of somatosensory rehabilitation on neural and functional recovery of LE in stroke patients. Thirty male and female patients were recruited and randomized to equal groups: control group (GI) and intervention group (GII). All patients were matched for age, duration of stroke, and degree of motor impairment of the affected LE. Both groups received standard program of physical therapy in addition to somatosensory rehabilitation for GII. The duration of treatment for both groups was eight consecutive weeks. Outcome measures used were Functional Independent Measure (FIM) and Quantitative Electroencephalography (QEEG), obtained pre- and post-treatment. A significant improvement was found in the FIM scores of the intervention group (GII), as compared to the control group (GI) (p < 0.001). Additionally, QEEG scores improved within the intervention group post-treatment. QEEG scores did not improve within the control group post-treatment, except for “Cz-AR”, compared to pretreatment, with no significant difference between groups. Adding somatosensory training to standard physical therapy program results in better improvement of neuromuscular control of LE function in chronic stroke patients.

Characteristics of Lower Limb Muscle Activity in Elderly Persons After Ergometric Exercise

This study examined the characteristics of lower limb muscle activity in elderly persons after ergometric pedaling exercise for 1 month. To determine the effect of the exercise, surface electromyography (SEMG) of lower limb muscles was subjected to Daubechies-4 wavelet transformation, and mean wavelet coefficients were compared with the pre-exercise coefficients and the post-exercise coefficients in each wavelet level. The characteristics of muscle activity after pedaling exercise were also compared between the elderly subjects and young subjects. For the elderly subjects, the mean wavelet coefficients were significantly decreased in the tibialis anterior and the gastrocnemius medialis at wavelet levels of 3, 4, and 5 (125–62.5, 62.5–31.25, and 31.25–15.625 Hz, respectively), by pedaling exercise. However, the mean power of wavelet levels of 2 and 3 (250–125 and 125–62.5 Hz) within the rectus femoris and the biceps femoris were significantly increased in the young subjects. The effect of pedaling exercise is different from the effects of heavy-resistance training. It was suggested that the muscle coordination, motor unit (MU) firing frequency, and firing fiber type of lower limb muscles are changed with the different characteristics between elderly and young persons by pedaling exercise for 1 month.

Pedaling improves gait ability of hemiparetic patients with stiff-knee gait: fall prevention during gait

BACKGROUND AND PURPOSE

Stiff-knee gait, which is a gait abnormality observed after stroke, is characterized by decreased knee flexion angles during the swing phase, and it contributes to a decline in gait ability. This study aimed to identify the immediate effects of pedaling exercises on stiff-knee gait from a kinesiophysiological perspective.

METHODS

Twenty-one patients with chronic post-stroke hemiparesis and stiff-knee gait were randomly assigned to a pedaling group and a walking group. An ergometer was set at a load of 5 Nm and rotation speed of 40 rpm, and gait was performed at a comfortable speed; both the groups performed the intervention for 10 min. Kinematic and electromyographical data while walking on flat surfaces were immediately measured before and after the intervention.

RESULTS

In the pedaling group, activity of the rectus femoris significantly decreased from the pre-swing phase to the early swing phase during gait after the intervention. Flexion angles and flexion angular velocities of the knee and hip joints significantly increased during the same period. The pedaling group showed increased step length on the paralyzed side and gait velocity.

CONCLUSIONS

Pedaling increases knee flexion during the swing phase in hemiparetic patients with stiff-knee gait and improves gait ability.

Skillful Cycling Training Induces Cortical Plasticity in the Lower Extremity Motor Cortex Area in Healthy Persons

Cycling exercise is commonly used in rehabilitation to improve lower extremity (LE) motor function and gait performance after stroke. Motor learning is important for regaining motor skills, suggesting that training of motor skills influences cortical plasticity. However, the effects of motor skill learning in dynamic alternating movements of both legs on cortical plasticity remain unclear. Here, we examined the effects of skillful cycling training on cortical plasticity of the LE motor area in healthy adults. Eleven healthy volunteers participated in the following three sessions on different days: skillful cycling training, constant-speed cycling training, and rest condition. Skillful cycling training required the navigation of a marker up and down curves by controlling the rotation speed of the pedals. Participants were instructed to fit the marker to the target curves as accurately as possible. Amplitudes of motor evoked potentials (MEPs) and short-interval intracortical inhibition (SICI) evoked using transcranial magnetic stimulation (TMS) were assessed at baseline, after every 10 min of the task (a total of 30 min), and 30 min after the third and final trial. A decrease in tracking errors was representative of the formation of motor learning following skillful cycling training. Compared to baseline, SICI was significantly decreased after skillful cycling training in the tibialis anterior (TA) muscle. The task-induced alterations of SICI were more prominent and lasted longer with skillful cycling training than with the other conditions. The changes in SICI were negatively correlated with a change in tracking error ratio at 20 min the task. MEP amplitudes were not significantly altered with any condition. In conclusion, skillful cycling training induced long-lasting plastic changes of intracortical inhibition, which corresponded to the learning process in the LE motor cortex. These findings suggest that skillful cycling training would be an effective LE rehabilitation method after stroke.

A Virtual Reality-Cycling Training System for Lower Limb Balance Improvement

Stroke survivors might lose their walking and balancing abilities, but many studies pointed out that cycling is an effective means for lower limb rehabilitation. However, during cycle training, the unaffected limb tends to compensate for the affected one, which resulted in suboptimal rehabilitation. To address this issue, we present a Virtual Reality-Cycling Training System (VRCTS), which senses the cycling force and speed in real-time, analyzes the acquired data to produce feedback to patients with a controllable VR car in a VR rehabilitation program, and thus specifically trains the affected side. The aim of the study was to verify the functionality of the VRCTS and to verify the results from the ten stroke patients participants and to compare the result of Asymmetry Ratio Index (ARI) between the experimental group and the control group, after their training, by using the bilateral pedal force and force plate to determine any training effect. The results showed that after the VRCTS training in bilateral pedal force it had improved by 0.22 (p = 0.046) and in force plate the stand balance has also improved by 0.29 (p = 0.031); thus both methods show the significant difference.

Gait training in subacute non-ambulatory stroke patients using a full weight-bearing gait-assistance robot: A prospective, randomized, open, blinded-endpoint trial

BACKGROUND

This study was a prospective, randomized, open, blinded-endpoint trial with the aim of examining whether gait training with a gait-assistance robot (GAR) improves gait disturbances in subacute non-ambulatory hemiplegic stroke patients more than overground conventional gait training. The GAR adopts a robot arm control system with full weight bearing and foot pressure visual biofeedback.

METHODS

Twenty-six hemiplegic patients were randomly assigned to either the GAR-assisted gait training (GAGT) group or the overground conventional gait training (OCGT) group. Both groups underwent 60 min of standard physical therapy and 20 min of GAGT or OCGT 5 days a week for 4 weeks. The primary outcome measure was the Functional Ambulation Classification (FAC). The secondary outcome measures were the peak torque of the extensor muscles in the lower extremities and a 10-m walking test. The lower extremity function was evaluated using the Fugl-Meyer Assessment, and activities of daily living were assessed using the Functional Independence Measure.

RESULTS

The GAGT group demonstrated significantly greater improvements in FAC and peak torque on the unaffected side (p=0.02) than the OCGT group. Additionally, gait speed tended to be faster (p=0.07) in the GAGT group.

CONCLUSIONS

GAGT combined with standard physical therapy in subacute non-ambulatory hemiplegic patients led to significant improvements in gait and peak torque on the unaffected side compared to OCGT.

The application of cycling and cycling combined with feedback in the rehabilitation of stroke patients: a review

Stroke is a leading cause of long-term disabilities, such as hemiparesis, inability to walk without assistance, and dependence of others in the activities of daily living. Motor function rehabilitation after stroke demands for methods oriented to the recovery of the walking capacity. Because of the similarities with walking, cycling leg exercise may present a solution to this problem. The aim of this article is to review the state of the art applications of cycling leg exercise as a (1) motor function rehabilitation method and an (2) aerobic training method for stroke patients as well as the commonly used (3) assessment tools. The cycling characteristics and applications, the applied test protocols as well as the tools used to assess the state and the recovery of patients and types of cycling devices are presented. In addition, the potential benefits of the use of other therapies, like feedback, together with cycling are explored. The application of cycling leg exercise alone and combined with feedback in stroke rehabilitation approaches has shown promising results. Positive effects on motor abilities were found in subacute and chronic patients. However, larger and normalized studies and assessments are needed because there is a high heterogeneity in the patients' characteristics, protocols and metrics. This wil allow the comparison between different studies related with cycling.

Evaluation of motor performances of hemiplegic patients using a virtual cycling wheelchair: an exploratory trial

Cycling is known to be an effective rehabilitation exercise for hemiplegic patients who face difficulty during walking because of stroke or other brain disorders. A cycling wheelchair (CWC) is a useful tool to provide exercise for these patients and improve their quality of life. In previous studies, our group developed a system that allows patients to safely practice driving a CWC in a virtual environment. However, it has been difficult to check their motor performances and determine the effects of the exercise on a daily basis. This study is an exploratory trial for developing a method to evaluate the motor performances of users based on their CWC pedaling patterns. An experiment with some hemiplegic patients and healthy subjects was conducted and their pedaling patterns were analyzed. Results showed a significant difference between the hemiplegic patients and healthy subjects in an index that reflects pedaling balance between the feet. This result indicates a possible method of evaluating the motor performances of users based on their pedaling patterns.

VRACK: measuring pedal kinematics during stationary bike cycling

Ankle impairment and lower limb asymmetries in strength and coordination are common symptoms for individuals with selected musculoskeletal and neurological impairments. The virtual reality augmented cycling kit (VRACK) was designed as a compact mechatronics system for lower limb and mobility rehabilitation. The system measures interaction forces and cardiac activity during cycling in a virtual environment. The kinematics measurement was added to the system. Due to the constrained problem definition, the combination of inertial measurement unit (IMU) and Kalman filtering was recruited to compute the optimal pedal angular displacement during dynamic cycling exercise. Using a novel benchmarking method the accuracy of IMU-based kinematics measurement was evaluated. Relatively accurate angular measurements were achieved. The enhanced VRACK system can serve as a rehabilitation device to monitor biomechanical and physiological variables during cycling on a stationary bike.

Neuromuscular and metabolic comparisons between ramp and step incremental cycle ergometer tests

INTRODUCTION

We compared peak and submaximal mean values for neuromuscular and metabolic parameters between ramp (15 W · min(-1)) and step (30 W increments every 2 min) incremental cycle ergometer tests.

METHODS

Thirteen healthy adults (7 men and 6 women; mean ± SD age = 23.4 ± 3.3 years) performed randomly ordered ramp or step incremental tests. Two-way repeated measures analyses of variance were used to analyze the data.

RESULTS

The ramp incremental test resulted in lower mean EMG amplitude, O2, and HR values at the common power outputs, with no differences for MMG amplitude values.

CONCLUSIONS

It is possible that the cumulative effect of producing an increased amount of work during the step (total work = 75.83 kJ) vs. ramp (total work = 65.60 kJ) incremental cycle ergometer tests at the common power outputs may have contributed to the greater fatigue-induced increase in muscle recruitment and/or firing rate, oxygen consumption, and heart rate.

Real-time changes in corticospinal excitability during voluntary contraction with concurrent electrical stimulation

While previous studies have assessed changes in corticospinal excitability following voluntary contraction coupled with electrical stimulation (ES), we sought to examine, for the first time in the field, real-time changes in corticospinal excitability. We monitored motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation and recorded the MEPs using a mechanomyogram, which is less susceptible to electrical artifacts. We assessed the MEPs at each level of muscle contraction of wrist flexion (0%, 5%, or 20% of maximum voluntary contraction) during voluntary wrist flexion (flexor carpi radialis (FCR) voluntary contraction), either with or without simultaneous low-frequency (10 Hz) ES of the median nerve that innervates the FCR. The stimulus intensity corresponded to 1.2× perception threshold. In the FCR, voluntary contraction with median nerve stimulation significantly increased corticospinal excitability compared with FCR voluntary contraction without median nerve stimulation (p<0.01). In addition, corticospinal excitability was significantly modulated by the level of FCR voluntary contraction. In contrast, in the extensor carpi radialis (ECR), FCR voluntary contraction with median nerve stimulation significantly decreased corticospinal excitability compared with FCR voluntary contraction without median nerve stimulation (p<0.05). Thus, median nerve stimulation during FCR voluntary contraction induces reciprocal changes in cortical excitability in agonist and antagonist muscles. Finally we also showed that even mental imagery of FCR voluntary contraction with median nerve stimulation induced the same reciprocal changes in cortical excitability in agonist and antagonist muscles. Our results support the use of voluntary contraction coupled with ES in neurorehabilitation therapy for patients.

Biomechanical assessments of the effect of visual feedback on cycling for patients with stroke

Stroke patients exhibit abnormal pattern in leg cycling exercise. The aim of this study was to investigate the effects of visual feedback on the control of cycling motion in stroke patients from kinesiological, kinematic and kinetic aspects. The cycling performance derived from cycling electromyography (EMG), cycling cadence, and torque of forty stroke subjects was evaluated under conditions with and without visual feedback of cycling cadence. Kinesiological indices, shape symmetry index (SSI) and area symmetry index (ASI) were extracted from EMG linear envelopes to evaluate the symmetry of muscle firing patterns during cycling. Roughness index (RI) was calculated from cycling cadence to represent cycling smoothness from kinematic aspects. Averaged cycling power (Pav), the product of cadence and torque, was used to represent force output. The rectus femoris EMG showed significantly greater ASI with visual feedback, however, the difference in SSI between the two conditions was not significant. For the biceps femoris, there was a significant decrease in SSI with visual feedback, while the ASI was not affected significantly by the task conditions. The cycling smoothness was better and the average power generated was larger when visual feedback was provided. This study found that the addition of visual feedback improved both neuromuscular control and overall performance. Such improvement is likely to be the result of better control of the rectus femoris muscle activation and coordination of both legs.

The cortical control of cycling exercise in stroke patients: an fNIRS study

Stroke survivors suffering from deficits in motor control typically have limited functional abilities, which could result in poor quality of life. Cycling exercise is a common training paradigm for restoring locomotion rhythm in patients. The provision of speed feedback has been used to facilitate the learning of controlled cycling performance and the neuromuscular control of the affected leg. However, the central mechanism for motor relearning of active and passive pedaling motions in stroke patients has not been investigated as extensively. The aim of this study was to measure the cortical activation patterns during active cycling with and without speed feedback and during power-assisted (passive) cycling in stroke patients. A frequency-domain near-infrared spectroscopy (FD-NIRS) system was used to detect the hemodynamic changes resulting from neuronal activity during the pedaling exercise from the bilateral sensorimotor cortices (SMCs), supplementary motor areas (SMAs), and premotor cortices (PMCs). The variation in cycling speed and the level of symmetry of muscle activation of bilateral rectus femoris were used to evaluate cycling performance. The results showed that passive cycling had a similar cortical activation pattern to that observed during active cycling without feedback but with a smaller intensity of the SMC of the unaffected hemisphere. Enhanced PMC activation of the unaffected side with improved cycling performance was observed during active cycling with feedback, with respect to that observed without feedback. This suggests that the speed feedback enhanced the PMC activation and improved cycling performance in stroke patients.

Effects of Lower Limb Reciprocal Pedalling Exercise on Motor Function after Stroke: A Systematic Review of Randomized and Nonrandomized Studies

This review systematically synthesized current evidence on the effects of lower limb reciprocal pedalling exercise on motor function poststroke. Detailed analysis of single studies in the review revealed multiple instances of heterogeneity including outcome measures; therefore we decided to avoid undertaking a single, potentially misleading meta-analysis. We found that despite beneficial (although nondefinitive) effects on balance, functional independence, and muscle strength, it is not possible to make clinical recommendations that support or refute the use of reciprocal pedalling exercise to enhance recovery of motor function after stroke. Our findings provide proof-of-concept for pedalling interventions and provide a foundation for subsequent research, suggesting a need for further standardized, controlled clinical trials of clearly described pedalling interventions for stroke survivors and with subsequent transparent reported findings.

Clinical efficacy and prognostic indicators for lower limb pedalling exercise early after stroke: study protocol for a pilot randomised controlled trial

Background

It is known that repetitive, skilled, functional movement is beneficial in driving functional reorganisation of the brain early after stroke. This study will investigate a) whether pedalling an upright, static exercise cycle, to provide such beneficial activity, will enhance recovery and b) which stroke survivors might be able to participate in pedalling.

Methods/Design

Participants (n = 24) will be up to 30 days since stroke onset, with unilateral weakness and unable to walk without assistance. This study will use a modified exercise bicycle fitted with a UniCam crank. All participants will give informed consent, then undergo baseline measurements, and then attempt to pedal. Those able to pedal will be entered into a single-centre, observer-blinded randomised controlled trial (RCT). All participants will receive routine rehabilitation. The experimental group will, in addition, pedal daily for up to ten minutes, for up to ten working days.

Prognostic indicators, measured at baseline, will be: site of stroke lesion, trunk control, ability to ambulate, and severity of lower limb paresis.

The primary outcome for the RCT is ability to voluntarily contract paretic lower limb muscle, measured by the Motricity Index. Secondary outcomes include ability to ambulate and timing of onset and offset of activity in antagonist muscle groups during pedalling, measured by EMG.

Discussion

This protocol is for a trial of a novel therapy intervention. Findings will establish whether there is sufficient evidence of benefit to justify proceeding with further research into clinical efficacy of upright pedalling exercise early after stroke. Information on potential prognostic indicators will suggest which stroke survivors could benefit from the intervention.

Trial Registration

ISRCTN: ISRCTN45392701

Seated Bilateral Leg Exercise Effects on Hemiparetic Lower Extremity Function in Chronic Stroke

Background. Bilateral arm training with rhythmic auditory cueing (BATRAC) improves hemiparetic upper extremity (UE) function in stroke. It is unknown whether a similar exercise for the hemiparetic lower extremity (LE) is effective. Objective. The authors sought to test whether the BATRAC strategy would transfer to the legs by improving LE motor function following ten 30-minute sessions of bilateral leg training with rhythmic auditory cueing (BLETRAC). Methods. Twenty-four chronic stroke participants, recruited from the community, were randomized to either the BLETRAC or the BATRAC intervention. Assessments were performed before (week 0) and after (week 6) training as well as 3 months later (week 18). Change in the Fugl-Meyer LE and UE subscales served as primary outcomes. Timed 10-m walk, movement parameters during treadmill walking, and a repetitive aiming task for both feet and hands were the secondary outcomes. Results . Following an intention-to-treat approach, data from 21 subjects were analyzed. After training, improvements in the Fugl-Meyer LE and UE subscales tended to be better for the corresponding intervention group. The BLETRAC group also showed increases in step length during treadmill walking and performance in the repetitive foot and hand aiming tasks. No differences between the intervention groups were found at follow-up. Conclusions. This exploratory trial demonstrates that transfer of the BATRAC approach to the legs is feasible. Transient improvements of limb motor function in chronic stroke participants were induced by targeted exercise (BATRAC for the UE and BLETRAC for the LE). It may be that further periods of training would increase and maintain effects.

Evaluation of functional electrical stimulation-assisted leg-propelled wheelchair in hemiplegic patients

BACKGROUND

Manual wheelchairs are an important mobility device for hemiplegic stroke patients, but understandably difficult to operate. A novel mobility device termed the functional electrical stimulation-assisted leg-propelled wheelchair (FES-LW) was proposed and a field test conducted to evaluate its clinical performance by comparison against a manual wheelchair (MW).

METHODS

A total of 20 hemiplegic patients were recruited from the National Cheng Kung University Hospital. They were instructed to successively propel the FES-LW and MW comfortably, as fast as possible, in along an oval pathway. The finish time, deviation frequencies, deviation percentage, physiological cost index (PCI), and modified Ashworth scale (MAS) of affected ankle were measured and compared.

FINDINGS

Subjects can propel the FES-LW with 40.1% less finish time (P=0.003); 23.7% lower deviation frequencies (P=0.009) and 36.7% lower deviation percentage (P=0.001); and 17.7% lower PCI (P=0.022) than the MW. In addition, the MAS of the affected ankle was noticeably reduced (P=0.002) after propelling the FES-LW.

INTERPRETATION

The FES-LW showed better controllability, cardiopulmonary response and positive effects on reducing spasticity versus the MW. The FES-LW is a suitable alternative to a MW for the needs of hemiplegic stroke patients.

The effects of a shank guide on cycling biomechanics of an adolescent with cerebral palsy: a single-case study

OBJECTIVE

To examine 3-dimensional lower-extremity joint kinematics and muscle activity during cycling with and without a shank guide for a single subject with spastic diplegic cerebral palsy (CP).

DESIGN

Single case.

SETTING

Pediatric referral hospital.

PARTICIPANT

A 13-year-old adolescent with spastic diplegic CP and limited ambulation abilities.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Kinematic data were collected for 6 joint motions and electromyographic data for 7 muscles during 10- to 15-second trials. Average variability in the kinematic curves was calculated, and kinematic and electromyographic data were analyzed descriptively.

RESULTS

With the guide, the subject cycled at 40.1+/-2.0 rpm compared with 13.7+/-4.0 rpm without it. In addition, there was less variability in the kinematic curves (P=.03) and muscles tended to turn on sooner and off later. These results indicate that this subject could cycle faster with the guide, which is desirable for cardiovascular health, and that there was a possible increase in motor control due to reduced needs to control excessive joint motions.

CONCLUSIONS

Based on these findings, a shank guide may allow some people with CP to cycle faster and provide improved joint kinematics.

Lower extremity muscle activity during cycling in adolescents with and without cerebral palsy

BACKGROUND

In individuals with cerebral palsy, adaptation and plasticity in the neuromuscular system can lead to detrimental changes affecting gait. Cycling may be an effective method to improve mobility. The biomechanics of cycling in adolescents with cerebral palsy have been studied, but further analysis of the frequency and amplitude characteristics of the electromyographic signals can assist with interpretation of the cycling kinematics.

METHODS

Data were analyzed from 10 adolescents with typical development (mean=14.9, SD=1.4 years) and 10 adolescents with cerebral palsy (mean=15.6, SD=1.8 years) as they cycled at two different cadences. Analyses of the lower extremity electromyographic signals involved frequency and amplitude analysis across the cycling revolution.

FINDINGS

Examination of cycling cadence revealed that adolescents with cerebral palsy had altered electromyographic characteristics in comparison to adolescents with typical development across the entire crank revolution for all muscles. Analyses of individual muscles indicated both inappropriate muscle activation and weakness.

INTERPRETATION

A more comprehensive analysis of electromyographic activity has the potential to provide insight into how a task is accomplished. In this study, the control of the several muscles, especially the rectus femoris, was significantly different in adolescents with cerebral palsy. This, combined with muscle weakness, may have contributed to the observed deviations in joint kinematics. Interventions that increase muscle strength with feedback to the nervous system about appropriate activation timing may be beneficial to allow individuals with cerebral palsy to cycle more efficiently.