Precision Versus Endurance Training to Improve Walking After Chronic Incomplete SCI
Condition: Spinal Cord Injury
MeSH terms: Spinal Cord Injuries
Study type: Interventional

Summary: 
      The objective of the study was to determine the efficacy of two forms of physical therapy
      training, one emphasizing precise, visually guided walking over obstacles and on targets
      (Precision Training), the other emphasizing mass practice of walking on a treadmill
      (Endurance Training). The hypothesis was that visually guided training (Precision) may be
      especially efficacious because it engages the motor cortex, whose input may facilitate
      improvements in functional walking. Participants are individuals with a chronic (≥7 months
      post-injury), motor incomplete spinal cord injury (SCI), with no other problems that would
      preclude participation in an intensive training program. A randomized, single-blinded,
      cross-over design was used to randomly allocate participants to start with Precision or
      Endurance Training, identified as Training Phase I. Training was 5x/wk for 2 months, followed
      by a 2-month rest period, identified as Rest Period I. Participants then returned for
      2-months of training in the other method, identified as Training Phase II, followed by
      another 2-month rest, Rest Period II. Measures of walking speed, distance, skill, confidence,
      as well as depression were obtained at least 3 times before any training, then monthly
      thereafter. Electrophysiological measures were taken before and after each phase of training
      and period of rest. Change scores were used to determine how each phase of training and rest
      influenced the scores (see below).
    

Detailed description: 
      PARTICIPANTS: Inclusion criteria: 1) SCI from trauma or other stable lesions, 2) injury
      occurred ≥ 7 mo prior, 3) able to walk independently at least 5 m with a walking aid and/or
      braces, 4) injury level between C1-L1, 5) able to give informed consent, 6) able to attend
      training sessions 5x/week. Exclusion criteria: 1) head injury, 2) cognitive or
      musculoskeletal impairments that preclude participation in walking training, 3) seizures or
      implants in the head that would preclude participation in experiments using transcranial
      magnetic stimulation (TMS).

      INTERVENTIONS:

      Precision Training. Training was performed on a 15 m long track. The track contained
      obstacles and targets. Obstacles were made of Styrofoam blocks of 3 cm height each, varying
      in width from 4 cm to 20 cm in divisions of 4 cm increments (which must be cleared without
      touching), and targets were made of fabric circles, ranging in diameter from 7-10.5 cm (which
      must be totally obscured by their foot). The difficulty of the track was designed to have the
      participant achieve ~80% success. The emphasis was on accuracy, not speed.

      Endurance Training. The aim of this training was mass practice. Participants walked on the
      treadmill, with body-weight support (BWS) and manual assistance if needed. The treadmill
      speed was initially set to be faster than their over ground walking speed as measured by the
      10 MWT(ss). Participants were encouraged to walk for as far and as fast as possible with
      minimal rest periods. Progression involved reducing manual assistance and BWS, increasing
      walking speed and distance, while reducing rest breaks.

      In both phases of training, a research assistant or volunteer recorded training parameters
      each session. The number of steps executed was measured with a step counter (StepWatch,
      Orthocare Innovations, USA), which was confirmed to be accurate with simultaneous manual
      counting prior to its use, and periodically during training sessions. The heart rate before
      and immediately after each bout of walking was measured with a heart rate monitor (Polar FT7,
      Polar, Canada). The total time, distance and walking speed for each walking bout was
      recorded.

      MEASURES:

      Measures were taken prior to all training at baseline (called Baseline I) and the end of each
      of the following intervals - one month of Training Phase I, two months of Training Phase I,
      one month of Rest Period I, two months of Rest Period I, one month of Training Phase II, two
      months of Training Phase II, one month of Rest Period II, two months of Rest Period II. To
      measure changes during the second phase of training, the baseline was the average of the one
      and two month measures of Rest Period I, henceforth called Baseline II.

      STATISTICAL ANALYSIS: To determined if one type of training was superior to the other, we
      compared the change scores (i.e., post-training score minus pre-training score) from each
      type of training using a standard t-test or a Mann-Whitney U test, as appropriate. Since
      individuals with high compared to low walking function may respond to the training
      differently, we divided individuals based on their pretraining walking speed as measured by
      the 10 MWT(ss) (i.e., > or < 0.5 m/s). The change scores from each of these groups of
      individuals were then compared for each type of training using a standard t-test or a
      Mann-Whitney U test, as appropriate. To determine the time course for obtaining a treatment
      effect, we compared the change scores for the first month (i.e., outcome measure at end of 1
      mo minus baseline) versus the second month (outcome measure at end of 2 mo minus at end of 1
      mo) of training for each type of training, using a standard t-test or a Mann-Whitney U test,
      as appropriate. Retention of gains was followed for 2 months after each type of training. The
      outcome measures at the end of the 2 month rest period were compared to the measures
      immediately after the training, for individuals that made improvements greater than the
      standard error of measurement for each measure, using a paired t-test or Wilcoxon signed-rank
      test, as appropriate.
    

Intervention name(s): Endurance; Precision
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Participants are trained daily to walk on a treadmill for as fast and as long as possible. A harness supporting part of their body weight can be used if needed. Assistance from a trainer is used if needed. A physical therapist supervises the training.; Participants train daily to walk over ground on 15 m straight hallway with obstacles they must step over, and targets they must step onto.
Other intervention name(s): Treadmill walking training; Body-weight supported treadmill training; Skill walking training
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: physical therapy; rehabilitation; neuroplasticity