Posts Tagged walking speed
[Abstract] Compensation or Recovery? Altered Kinetics and Neuromuscular Synergies Following High-Intensity Stepping Training Poststroke
Background. High-intensity, variable stepping training can improve walking speed in individuals poststroke, although neuromuscular strategies used to achieve faster speeds are unclear. We evaluated changes in joint kinetics and neuromuscular coordination following such training; movement strategies consistent with intact individuals were considered evidence of recovery and abnormal strategies indicative of compensation.
Methods. A total of 15 individuals with stroke (duration: 23 ± 30 months) received ≤40 sessions of high-intensity stepping in variable contexts (tasks and environments). Lower-extremity kinetics and electromyographic (EMG) activity were collected prior to (BSL) and following (POST) training at peak treadmill speeds and speeds matched to peak BSL (MATCH). Primary measures included positive (concentric) joint and total limb powers, measures of interlimb (paretic/nonparetic powers) and intralimb compensation (hip/ankle or knee/ankle powers), and muscle synergies calculated using nonnegative matrix factorization.
Results. Gains in most positive paretic and nonparetic joint powers were observed at higher speeds at POST, with decreased interlimb compensation and limited changes in intralimb compensation. There were very few differences in kinetic measures between BSL to MATCH conditions. However, the number of neuromuscular synergies increased significantly following training at both POST and MATCH conditions, indicating gains from training rather than altered speeds. Despite these results, speed improvements were associated primarily with changes in nonparetic versus paretic powers.
Conclusion. Gains in locomotor function were accomplished by movement strategies consistent with both recovery and compensation. These and other data indicate that both strategies may be necessary to maximize walking function in patients poststroke.
via Compensation or Recovery? Altered Kinetics and Neuromuscular Synergies Following High-Intensity Stepping Training Poststroke – Marzieh M. Ardestani, Catherine R. Kinnaird, Christopher E. Henderson, T. George Hornby, 2019
[ARTICLE] Speed-adaptive control of functional electrical stimulation for dropfoot correction – Full Text
Functional electrical stimulation is an important therapy technique for dropfoot correction. In order to achieve natural control, the parameter setting of FES should be associated with the activation of the tibialis anterior.
This study recruited nine healthy subjects and investigated the relations of walking speed with the onset timing and duration of tibialis anterior activation. Linear models were built for the walking speed with respect to these two parameters. Based on these models, the speed-adaptive onset timing and duration were applied in FES-assisted walking for nine healthy subjects and ten subjects with dropfoot. The kinematic performance of FES-assisted walking triggered by speed-adaptive stimulation were compared with those triggered by the heel-off event, and no-stimulation walking at different walking speeds.
Higher ankle dorsiflexion angle was observed in heel-off stimulation and speed-adaptive stimulation conditions than that in no-stimulation walking condition at all the speeds. For subjects with stroke, the ankle plantarflexion angle in speed-adaptive stimulation condition was similar to that in no-stimulation walking condition, and it was significant larger than that in heel-off stimulation condition at all speeds.
The improvement in ankle dorsiflexion without worsening ankle plantarflexion in speed-adaptive stimulation condition could be attributed to the appropriate stimulation timing and duration. These results provide evidence that the proposed stimulation system with speed-related parameters is more physiologically appropriate in dropfoot correction, and it may have great potential value in future clinical applications.
About three quarters of stroke survivors experience different levels of brain dysfunction and movement disorder , which result in lower living quality and limited ability in social activities . Of these subjects, 20% suffer from impaired motor function in the lower extremities. One of such impairments is dropfoot, which is characterized by poor ankle dorsiflexion during the swing phase and an inability to achieve heel strike at the initial contact [3, 4]. Abnormal gaits such as circumduction gait and abnormal foot clearance on the affected side are often found as a method of compensating for excessive hip abduction and pelvis elevation on the unaffected side . This results in gait asymmetry and slow walking speed .
Functional electrical stimulation was a representative intervention to correct dropfoot and Liberson et al. first introduced functional electrical stimulation (FES) to correct dropfoot for chronic hemiplegic subjects in the 1960s . An electrical charge is delivered via a pair of electrodes to activate the tibialis anterior (TA), which results in ankle dorsiflexion. Yan et al. applied two dual-channel stimulators to the quadriceps, hamstring, gastrocnemius, and TA to recover motor function of the lower extremities in an early stage after stroke . The stimulation was followed by a predetermined sequence of muscle activations that mimic a healthy gait cycle . The duration of stimulation was five seconds in Yan et al.’s study. However, subjects with different severities of impairment might have different walking speeds , which means that a fixed stimulation duration might not be able to account for different walking patterns.
Liberson et al. used the heel-off event detected by a footswitch to trigger the stimulation . However, the reliability of the footswitch controller was significantly reduced when subjects who dragged their feet during walking encountered a slope or an obstacle . Bhadra et al. proposed a manual switch to trigger stimulation as a walking aid for subjects with spinal cord injury (SCI) . However, manual control may distract subjects from maintaining balance and lead to an increased risk of falls [13, 14]. Furthermore, the cable between the control sensor and stimulator was inconvenient for walking .
Instead of a footswitch, Mansfield et al.  and Monaghan et al.  detected the heel event of the gait cycle in FES-assisted walking using an accelerometer and a uniaxial gyroscope, respectively. The commercially available product WalkAide also uses an accelerometer for this purpose . Electromyography (EMG) signal is also applied as a control source in FES-assisted walking for the detection of volitional intent of muscle . Yeom et al. amplified the EMG signal of the TA and modulated the stimulation intensity in proportion to the integrated EMG envelope. The electrical pulses are then sent to the common peroneal nerve for dropfoot correction .
In these studies, FES applied to the TA was mainly triggered by the heel-off event. However, this event occurs during the push-off phase and before TA activation . An earlier start of TA stimulation results in reduced ankle plantarflexion . Spaich et al. suggested implementing a constant time interval before the onset timing of TA stimulation to extend the push-off phase before the ankle dorsiflexion . Some studies have found that walking speed can affect the activation of TA [22, 23]. Shiavi et al. found that the duration of EMG activity decreased as speed increased . In Winter et al.’s study, the shape of the EMG patterns generally remained similar at the different walking speeds and the duration of EMG activity was closely related to the normalized stride time . Although the duration of TA activation changes with the walking speeds has been reported , the selection of speed-adaptive FES parameters for TA has not been investigated.
The objective of this study is to find a more physiologically appropriate FES design for dropfoot correction. Firstly, speed-related changes in onset timing and the duration of TA activation were examined. Next, linear models were built for the walking speed and time interval from the heel-off event to the onset timing of TA activation, as well as for the walking speed and the duration of the TA activation. The speed-adaptive stimulation (SAS) timing and duration were then calculated based on the two models and applied for FES-assisted walking. Finally, the performance of stimulation triggered by SAS, heel-off event (HOS) and no stimulation (NS) were compared during FES-assisted walking on both subjects with stroke and healthy subjects at different walking speeds.[…]
A new meta-analysis of existing studies shows that a technique called repetitive transcranial magnetic stimulation might be a useful tool to help stroke survivors regain the ability to walk independently.
Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain stimulation technique; magnetic coils are placed on a person’s scalp, and short electromagnetic pulses are delivered to specific brain areas through the coil.
Although these pulses only cause an almost imperceptible “knocking or tapping” sensation for the patient undergoing the procedure, they reach into the brain, triggering electric currents that stimulate neurons.
rTMS has mainly been used to treat psychosis, depression, anxiety, and other mood disorders with a fair degree of success. In a recent study, more than one third of people living with auditory verbal hallucinations — a marker of schizophrenia — reported a reduction in their symptoms following the procedure.
But researchers have also been delving into the potential that the technique has for improving life after stroke. Four years ago, for instance, a team of researchers at The Ohio State University Wexner Medical Center in Columbus used rTMS to improve arm movement in people who had experienced a stroke, and more studies have explored this therapeutic potential since.
Now, a team of researchers — jointly led by Dr. Chengqi He, of Sichuan University in the People’s Republic of China, and Shasha Li, of Massachusetts General Hospital and Harvard Medical School, both in Boston, MA — set out to review these studies.
Dr. He and colleagues wanted to see if the technique improved motor skills for people who had stroke; to do so, the researchers examined the impact rTMS has on walking speed, balance, and other key factors for post-stroke rehabilitation.
The findings were published in the American Journal of Physical Medicine & Rehabilitation, the official journal of the Association of Academic Physiatrists.
rTMS ‘significantly improves walking speed’
Dr. He and team reviewed nine studies of rTMS — including five randomized controlled trials — which were published between 2012 and 2017.
The people who participated in these studies had either had an ischemic stroke — that is, a stroke caused by a blood clot in one of the brain’s arteries — or a hemorrhagic stroke — that is, one caused by bleeding within the brain.
Of the nine studies, six included data on the walking speed of 139 stroke survivors. The researchers carried out a pooled analysis of these studies, and the results revealed that rTMS “significantly improves walking speed.”
This improvement was greater among people who received stimulation on the same side of the brain that the stroke occurred. By contrast, those who received rTMS on the opposite side did not see any improvement.
Other key health outcomes for stroke survivors such as balance, motor function, or brain responsiveness did not show any improvement as a result of rTMS.
In the United States, it is estimated that almost 800,000 people annually have a stroke, which makes the condition a leading cause of long-term disability in the country. More than half of the seniors who survived a stroke have reduced mobility as a result.
Although the review shows that rTMS is a promising strategy for restoring independent walking, the authors say that more research is needed. Dr. He and colleagues conclude:
“Future studies with larger sample sizes and an adequate follow-up period are required to further investigate the effects of rTMS on lower limb function and its relationship with changes in cortical excitability with the help of functional neuroimaging techniques.”
[Abstract] Novel multi-pad functional electrical stimulation in stroke patients: A single-blind randomized study
[ARTICLE] Effectiveness of a multimodal exercise rehabilitation program on walking capacity and functionality after a stroke – Full Text
The aim of this study was to determine the effectiveness of a 12-week multimodal exercise rehabilitation program on walking speed, walking ability and activities of daily living (ADLs) among people who had suffered a stroke. Thirty-one stroke survivors who had completed a conventional rehabilitation program voluntarily participated in the study. Twenty-six participants completed the multimodal exercise rehabilitation program (2 days/wk, 1 hr/session). Physical outcome measures were: walking speed (10-m walking test), walking ability (6-min walking test and functional ambulation classification) and ADLs (Barthel Index). The program consisted on: aerobic exercise; task oriented exercises; balance and postural tonic activities; and stretching. Participants also followed a program of progressive ambulation at home. They were evaluated at baseline, postintervention and at the end of a 6-month follow-up period. After the intervention there were significant improvements in all outcomes measures that were maintained 6 months later. Comfortable and fast walking speed increased an average of 0.16 and 0.40 m/sec, respectively. The walking distance in the 6-min walking test increased an average of 59.8 m. At the end of the intervention, participants had achieved independent ambulation both indoors and outdoors. In ADLs, 40% were independent at baseline vs. 64% at the end of the intervention. Our study demonstrates that a multimodal exercise rehabilitation program adapted to stroke survivors has benefits on walking speed, walking ability and independence in ADLs.
Keywords: Exercise, Physical activity, Stroke rehabilitation, Walking speed, Activities of daily living
As life expectancy increases, a larger number of persons may suffer from stroke. Stroke mortality rates have decreased, but the burden of stroke is increasing in terms of stroke survivors per year, correlated deaths and disability-adjusted life-years lost. These deficiencies are further highlighted by a trend towards more strokes in younger people (Feigin et al., 2014). Stroke not only causes permanent neurological deficits, but also a profound degradation of physical condition, which worsens disability and increases cardiovascular risk. Stroke survivors are likely to suffer functional decline due to reduction of aerobic capacity. This may involve further secondary complications such as progressive muscular atrophy, osteoporosis, peripheral circulation worsening and increased cardiovascular risk (Ivey et al., 2006). All these factors cause increased dependency, need of assistance from third parties in activities of daily living (ADLs) and a restriction on participation that can have a profound psychosocial impact (Carod-Artal and Egido, 2009). Gait capacity is one of the main priorities of persons who have suffered a stroke, but is often limited due to the high energy demands of hemiplegic gait and the poor physical condition of these persons (Ivey et al., 2006). Gait speed is a commonly used measure in patients who have suffered a stroke to differentiate the functional capacity to walk indoors or outdoors. Gait speed has been classified as: allowing indoor ambulation (<0.4 m/sec), limited outdoor ambulation (0.4–0.8 m/sec), and outdoor functional ambulation (>0.8 m/sec) (Perry et al., 1995). Gait speed can also help to establish the functional prognosis of the patient. It has been stated that improvements in walking speed correlate with improved function and quality of life (QoL) (Schmid et al., 2007). It is essential to achieve a proper gait speed for outdoors functional ambulation.
Falls are common among stroke survivors and are associated with a worsening of disability and QoL. Balance is a complex process that involves the reception and integration of afferent inputs and the planning and execution of movement. Stroke can impact on different systems involved in postural control. Multifactorial falls risk assessment and management, combined with fitness programs, are effective in reducing risk of falls and fear of falling (Stroke Foundation of New Zealand and New Zealand Guidelines Group, 2010). Falls often occur when getting in and out of a chair (Brunt et al., 2002). The 2013 Cochrane review (Saunders et al., 2013) recommends the repetitive practice of sit-to-stand in order to promote an ergonomic and automatic pattern of this movement. Recent studies demonstrate that exercises that improve trunk stability and balance provide a solid base for body and leg movements that entail an improved gait in people affected by stroke (Sharma and Kaur, 2017). Conventional rehabilitation programs after stroke focus on the subacute period. The aim is to recover basic ADLs, but they do not provide maintenance exercises to provide long-term health gains. Cardiac monitoring demonstrates that conventional physiotherapy exercises do not regularly provide adequate exercise intensity to modify the physical deconditioning, nor sufficient exercise repetition to improve motor learning (Ivey et al., 2006). Therapeutic physical exercise to optimize function, physical condition and cardiovascular health after a stroke is an emerging field within neurorehabilitation (Teasell et al., 2009). The wide range of difficulties experienced by stroke survivors justify the need to explore rehabilitation programs designed to promote an overall improvement and to maintain the gains obtained after rehabilitation programs. Numerous studies have demonstrated the efficacy of aerobic exercise (Saunders et al., 2016), but there are few data on the long term effects of multimodal programs that incorporate aerobic exercise, complemented by task-oriented training and balance exercises. Consequently, the aim of this study is to analyse the impact of a multimodal exercise rehabilitation program tailored to stroke survivors on walking speed, walking ability and ADLs. […]
[ARTICLE] Effects of dual-task and walking speed on gait variability in people with chronic ankle instability: a cross-sectional study – Full Text
Recent evidence suggests that impaired central sensorimotor integration may contribute to deficits in movement control experienced by people with chronic ankle instability (CAI). This study compared the effects of dual-task and walking speed on gait variability in individuals with and without CAI.
Sixteen subjects with CAI and 16 age- and gender-matched, able-bodied controls participated in this study. Stride time variability and stride length variability were measured on a treadmill under four different conditions: self-paced walking, self-paced walking with dual-task, fast walking, and fast walking with dual-task.
Under self-paced walking (without dual-task) there was no difference in stride time variability between CAI and control groups (P = 0.346). In the control group, compared to self-paced walking, stride time variability decreased in all conditions: self-paced walking with dual-task, fast speed, and fast speed with dual-task (P = 0.011, P = 0.016, P = 0.001, respectively). However, in the CAI group, compared to self-paced walking, decreased stride time variability was demonstrated only in the fast speed with dual-task condition (P = 1.000, P = 0.471, P = 0.008; respectively). Stride length variability did not change under any condition in either group.
Subjects with CAI and healthy controls reduced their stride time variability in response to challenging walking conditions; however, the pattern of change was different. A higher level of gait disturbance was required to cause a change in walking in the CAI group compared to healthy individuals, which may indicate lower adaptability of the sensorimotor system. Clinicians may use this information and employ activities to enhance sensorimotor control during gait, when designing intervention programs for people with CAI.
The study was registered with the Clinical Trials network (registration NCT02745834, registration date 15/3/2016).
Recurrent ankle sprains occur in up to 40% of individuals who have previously experienced a lateral ankle sprain [1, 2]. Individuals who report residual symptoms, which include repetitive episodes of ‘giving way’ and subjective feeling of ankle joint instability are termed as having chronic ankle instability (CAI) . The cause of these symptoms and the high frequency of recurrent ankle sprain is not fully understood . It has been suggested that the residual joint instability and the high reoccurrence rates can be attributed to loss of sensory input from articular mechano-receptors, decreased muscle strength, mechanical instability of the ankle joint, and reduced ankle range of motion [5, 6].
Recent evidence suggests that deficits in central neural sensorimotor integration can contribute to impaired movement control in people with CAI [7, 8, 9, 10, 11, 12, 13, 14]. For example, Springer et al.  assessed the correlation between single-limb stance postural control (Overall Stability Index) and shoulder position sense (Absolute Error Score) among people with CAI and healthy controls. Correlations between the lower and upper limbs were observed only in the healthy controls, indicating altered sensorimotor integration in the CAI group. Several studies have observed altered gait mechanism in people with CAI, which was explained by compromised central nervous system (CNS) control [9, 14, 15, 16]. It was shown that people with CAI have a typical gait pattern of increased inversion kinematics and kinetics, lateral shift of body weight, increased hip flexion during terminal swing to mid stance, reduced hip extension and increased knee flexion during terminal stance to initial swing, and slow weight transfer at the beginning and end of the stance [15, 16, 17]. Altered biomechanical strategies during gait initiation and termination tasks (e.g., reduced center of pressure displacement), have also been demonstrated in this population [9, 14]. Studies that assessed movement variability, such as knee and hip joint motions during single leg jump landing, identified differences between individuals with and without CAI, which may also indicate central motor programming deficits [10, 11, 12, 13]. Hence, further investigation of motor control adaptations may contribute to understanding the underlying neurophysiologic mechanisms of CAI.
Gait speed and other spatio-temporal parameters during daily activities should reflect behavioral goals and environmental conditions . Studies revealed that walking speed has a significant effect on joint coordination pattern and gait variability [18, 19, 20]. Therefore, assessing gait variability under challenging situations such as walking at different speeds might test CNS flexibility in controlling gait [19, 20]. Moreover, based on the understanding that for many daily activities even a fully intact motor control system requires attention and cognitive resources , the dual-task paradigm has been used to provide insight into the demands of postural control and gait on attention. Performance of a cognitive task has been shown to decrease postural control in participants with CAI as compared to healthy controls [7, 22]. However, no previous study examined the impact of cognitive task and walking speed on gait performance in subjects with CAI.
Balance during walking is reflected by precise spatial and temporal control of foot placement. Stride to stride fluctuations in time and length are related to control of the rhythmic walking mechanism. Thus, previous research has suggested that studying gait variability is a reliable way to quantify locomotion . The mechanism of adjusting movement variability is considered beneficial for coping with changes, maintaining stability, preventing injury, and attaining higher motor skills . Performing a cognitive task while walking or while altering self-paced walking speed has been related to changes in gait variability in populations with neurological and musculoskeletal pathologies, as well in healthy young individuals [25, 26, 27, 28]. Yet, there is no consensus in the literature as to how to interpret these changes. Decreased variability while performing demanding gait tasks may reflect voluntary gait adaptation toward a more conservative gait pattern . Alternatively, it has been suggested that increased variability may indicate CNS flexibility and adaptability to changes in task demands . A possible central sensorimotor control deficit in people with CAI may constrain the ability of the CNS to adjust to different task demands; thus, affecting central control over gait variability and reducing the ability to cope with varied tasks. Consequently, testing the mechanism of adjusting gait variability as a response to complex walking conditions in people with CAI compared to healthy controls may provide more information on sensorimotor control in this population.
The present study was designed to compare the effects of dual-task and walking speed on gait variability in individuals with and without CAI. Previous reports, including a meta-analysis, indicated that simple postural tasks do not always discriminate between participants with CAI and those without [6, 8, 30]. Consequently, we hypothesized that gait variability among individuals with and without CAI will be similar during “normal” self-paced walking, whereas gait will vary under complex walking conditions.[…]
[ARTICLE] Sustained effects of once-a-week gait training with hybrid assistive limb for rehabilitation in chronic stroke: case study
[Purpose] The purpose of this study was to investigate the accumulated and sustained effects of oncea-week gait training with a powered exoskeleton suit, Hybrid Assistive Limb, in a subject with chronic stroke.
[Subject and Methods] The subject was a woman in her early sixties who had stroke onset approximately 5 years ago. A single-case ABA design was used. A 2-month baseline period was followed by an 8-week period of weekly gait training and a subsequent 2-month follow-up period. Throughout the study period, she underwent conventional physiotherapy. Outcome measures were the 10-meter walking test, timed up and go test, functional reach test, twostep test, and Berg Balance Scale.
[Results] Significant improvements were seen in all outcome measures during the gait training period. Improvements in all outcome measures except walking speed were maintained at follow-up.
[Conclusion] Continued gait training with Hybrid Assistive Limb once a week can improve gait and balance performance in patients with chronic stroke, and these improvements are maintained at least for two months.
[Abstract] Contribution of Paretic and Nonparetic Limb Peak Propulsive Forces to Changes in Walking Speed in Individuals Poststroke
Background. Recent rehabilitation efforts after stroke often focus on increasing walking speed because it is associated with quality of life. For individuals poststroke, propulsive force generated from the paretic limb has been shown to be correlated to walking speed. However, little is known about the relative contribution of the paretic versus the nonparetic propulsive forces to changes in walking speed.
Objective. The primary purpose of this study was to determine the contribution of propulsive force generated from each limb to changes in walking speed during speed modulation within a session and as a result of a 12-week training program.
Methods. Gait analysis was performed as participants (N = 38) with chronic poststroke hemiparesis walked at their self-selected and faster walking speeds on a treadmill before and after a 12-week gait retraining program.
Results. Prior to training, stroke survivors increased nonparetic propulsive forces as the primary mechanism to change walking speed during speed modulation within a session. Following gait training, the paretic limb played a larger role during speed modulation within a session. In addition, the increases in paretic propulsive forces observed following gait training contributed to the increases in the self-selected walking speeds seen following training.
Conclusions. Gait retraining in the chronic phase of stroke recovery facilitates paretic limb neuromotor recovery and reduces the reliance on the nonparetic limb’s generation of propulsive force to increase walking speed. These findings support gait rehabilitation efforts directed toward improving the paretic limb’s ability to generate propulsive force.
For the stroke patient who is already walking but wants to improve speed of walking or the ability to make transitional movement, it is important to vary the routine and incorporate a variety of exercises. Transitional movement involves changing from one position to another. Examples of transitional movement include getting up and down, making turns, navigating up or down a step, changing directions, etc.
In order to improve gait speed and transitional movement, it is a good idea to incorporate exercises that are challenging. Some examples would include stair stepping, dance moves, walking over uneven surfaces, side stepping, walking backwards, getting up and down from the floor, and climbing up/down hills. Other activities to incorporate into the exercise routine would include walking on a treadmill or riding a stationary bike at various speeds as well as including strengthening exercises to help weak musculature. Obviously some of these exercises may be too hard for some patients so it is important to consult with your own therapist to see what exercises may work for you.
By incorporating a good mix of exercises, you challenge your body more similar to the way that it is used in real lift. If you simply do leg raises, knee extensions, and foot circles with ten minutes of riding a stationary bike, you are in no way challenging yourself to experience the situations you come across in real life. Such situations include navigating curbs or stairs, walking over uneven grass/dirt, going up/down a ramp or stairs, holding a door open while trying to walk through it, getting up off the floor or a low seat, bending down to get something off the floor or out of the closet, etc. Our body does not simply move in a linear patterns walking only forward. There are twists and turns involved requiring complex patterns of movement.
It is important to challenge yourself and talk to your therapist about making sure your therapy program is challenging enough. For some ideas of exercises to improve gait, I recommend looking over the FAME program from the University of British Columbia. The exercises are meant for a group exercise program with supervision from an instructor, but the exercises presented would be beneficial even to an individual as long as adequate assistance is given. Remember to check with your therapist before trying any new exercises as the exercises may not be appropriate for you.
[ARTICLE] Effects of Functional Limb Overloading on Symmetrical Weight Bearing, Walking Speed, Perceived Mobility, and Community Participation among Patients with Chronic Stroke – Full Text HTML
Background. Stroke is a leading cause for long-term disability that often compromises the sensorimotor and gait function accompanied by spasticity. Gait abnormalities persist through the chronic stages of the condition and only a small percentage of these persons are able to walk functionally in the community.
Material and Method. Patients with chronic stroke were recruited from outpatient rehabilitation unit at Department of Neurology & Neurosurgery, All India Institute of Medical Sciences, having a history of first stroke at least six months before recruitment, with unilateral motor deficits affecting gait. The patients were randomly assigned to either the functional limb overloading (FLO) or Limb Overloading Resistance Training (LORT) group and provided four weeks of training.
Result. We found that there was an improvement in gait performance, weight bearing on affected limb, and perceived mobility and community participation.
Conclusion. To the best of our knowledge, this is the first study that has evaluated the effects of functional limb overloading training on symmetric weight bearing, walking ability, and perceived mobility and participation in chronic hemiplegic population. The study demonstrated a beneficial effect of training on all the outcomes, suggesting that the functional limb overloading training can be a useful tool in the management of gait problems in chronic stroke patients.
Stroke is becoming a rapidly increasing problem and an important cause of disability and deaths worldwide. Incidence and prevalence of strokes in Saudi Arabia are comparatively lower than western countries, which could be because of the predominance of the younger age groups in this region . The annual stroke incidence ranged from 27.5 to 63 per 100,000 population and prevalence ranged from 42 to 68 per 100,000 population .
Stroke is a leading cause for long-term disability due to compromised sensorimotor function. Approximately 85% of stroke survivors learn to walk independently by 6 months after stroke, but gait abnormalities persist throughout the chronic stages of the condition. Only a small percentage of stroke survivors are able to walk functionally in the community [3, 4].
The objective of stroke rehabilitation is to enable individual patients to maximize benefits from training in order to attain the highest possible degree of physical and psychological performance. The ultimate goals for many stroke patients are to achieve a level of functional independence necessary for returning home and to integrate as fully as possible into community life.
Ng and Hui-Chan  have noted that weakness in hemiplegic stroke patients is sometimes overshadowed over concerns about treatment of spasticity and synergistic movements. Studies have revealed positive correlations between the strength of specific muscle groups and a variety of functional attributes . Furthermore, a nonlinear relationship between walking performance and muscle strength in the lower extremities has been suggested . However, as the protocols were multifaceted, it was not possible to determine the precise role that the strength-training component may have played in improving walking function.
A number of studies have shown that task specificity and intensity of training are the main determinants of functional improvement after stroke [6, 8, 9]. Moreover, there is growing evidence suggesting that intensive task-oriented practice can induce greater improvement in walking competency than usual practice in stroke survivors [10–12].
Yang et al.  in their study on stroke patients undergoing progressive lower limb strengthening using functional weight bearing activities found moderate increases in walking speed. Sullivan et al.  found that task-specific training with body-weight support is more effective in improving walking speed but lower limb strength training did not provide any added benefit to walking outcomes.
A major limitation to the conclusions from these studies and systematic reviews is the lack of consistency in the intervention and specified protocols [15–17]. Despite the number of studies dedicated to task-oriented training, none of these studies had combined functional task training with prolonged resistance in the form of limb overloading applied 90% of the awake time. Therefore, we designed this study to address the evidence related to our training protocol to enhance symmetric weight bearing and walking speed and its impact on perceived mobility and community participation in patients with chronic stroke.
We hypothesized that intervention programs that combine lower limb overload with functional task training would be more effective at improving walking outcomes and community participation than lower limb overload training alone.
The design of our study was influenced by the literature on lower extremity strength training and task-specific locomotor training [14, 18, 19]. The use of this design should provide…