Running Training After Stroke: A Single-Subject Report.

Miller, Ellen, Stephanie Combs, Caryn Fish, et al.

Summary by Sonya Seif, Mobility Research

An interesting problem for patients who have suffered stroke, brain injury, or other neurological impairment is the transition from achieving functional walking patterns to regaining an ability to run. Since therapy is almost exclusively halted after the patient has achieved a minimal level of function that will allow him or her to operate safely within the community. When injury happens at a younger age (28% of strokes occur in patients under 65 years of age) it can be the case that the patient had enjoyed a certain level of physical activity before the injury—recreational running, for example—to which they never return. Whether or not therapy techniques can be used to achieve that goal has not been extensively studied. Some previous research has shown that speed-progressive gait intervention in a body weight support/treadmill (BWST) environment significantly increases overground walking and running speeds following training for a (single) patient with an incomplete C5-C6 spinal cord injury (Gardner, et al.). This success prompted the suggestion that speed-progressive gait training in a BWST environment would be a useful technique for improving functional outcomes in people with other neurological impairments.

In this study, Miller, et al., investigated the feasibility and effectiveness of using intensive task-oriented training in a BWST environment to improve running for a single stroke patient - a 38-year old male 2.5 years post-stroke. Before intervention, the participant could walk independently, but running was inefficient, slow, and unsafe. It was hypothesized that his running ability would improve with improved running speed and symmetry, endurance, balance, strength, and self-reported quality of life. The parameters investigated included the following: hip flexion, hip abduction, hip extension, knee extension, knee flexion, plantar flexion, dorsiflexion, eversion, 25-m sprint time, single-leg balance, running step width, running step length ratio, lower-extremity strength, and the 6-minute walk test. Parameters on the Stroke Impact Scale (SIS) were also evaluated (physical, emotion, handicap, stroke recovery). Therapy was administered three times per week for an 8-week period. Baseline measurements were taken over a three week period prior to intervention, measurements were recorded weekly over the course of the therapy, immediately post-intervention, and then six months post-intervention.

Therapy sessions consisted of using a LiteGait® I 400 with a FlexAble™ yoke system (Mobility Research, Tempe, AZ) over a treadmill for 3 bouts of running, each lasting 10 minutes. Each bout consisted of a 1.5 minute warm-up of fast walking, 7.5 minutes of running, and a 1-minute cool-down. All speeds were self-selected by the participant, though he was encouraged to go as fast as he could. Therapist feedback consisted of visual and verbal cues to facilitate optimal symmetry and alignment (e.g. increase left step length, control right ankle, equalize arm swing). At the beginning of the intervention, the participant was observed running with 20%, 10% and 0% BWS (measured in stationary double stance); 20% was deemed an appropriate starting place because it allowed him to practice the best running technique, as defined by an upright and slightly forward trunk, maximum hip extension at the end of the stance, effective swing-through, and optimal step length and heel contact. Therapy progressed through decreases in BWS (20% to 10% to 0%) and increases in treadmill speed. BWS was decreased when the patient could run three 10-minute bouts with fewer than 10 scuffs during the eighth minute of the last bout. After 0% was reached, BWS was further decreased to 0% at 25% step length and then 0% at 50% step length to remove the support given at the lower bounds of vertical displacement during running.

Comparing the baseline results to the six-month post-intervention mark, results indicated a statistically significant increase in left single leg balance and improvement in strength - right dorsiflexion, right hip flexion and abduction, and left hip flexion were all within 1 standard deviation of reported strength norms. From the baseline to the immediately post-intervention mark, the 6-minute walk test improved by 42%. An interesting observation was made with regard to symmetry: although the participant's step length ratio decreased from 1.02 to 0.92, his consistency improved and he developed a rhythm that facilitated better running. It is unclear whether or not symmetry should be an important consideration for this patient, though it has been shown that repeated asymmetrical running patterns can lead to musculoskeletal complications in healthy people. In addition to the improvement in physical benchmarks, statistically significant increases were seen in the SIS domains of emotion, handicap and stroke recovery.

Six months after intervention he had returned to recreational running and the perception of his quality of life had greatly increased. It is the conclusion of the authors that an intensive, task-specific training program based in a clinical research setting was feasible and effective for retraining running ability in a 38-year-old man 2.5 years after stroke. The results of this study strongly support body weight support/treadmill training combined with task-specific, speed-dependent training as a safe and effective therapeutic environment for higher level patients who have a desire to regain the ability to run. While running is generally overlooked as a clinical goal for high performing patients with a stroke, TBI, cerebral palsy, or other neurological condition, working on achieving higher level skills could allow for a greater degree of perceived normalcy and return the patient to a higher quality of life.