Precision Versus Endurance Training to Improve Walking After Chronic Incomplete SCI

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).

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.

Participants to start with Endurance Training. 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. Training was 5x/wk for 2 months, followed by a 2-month rest period. Participants then returned for training in the Precision Training 5x/wk for 2 months.Participants train to walk over ground on 15 m straight hallway with obstacles they must step over, and targets they must step onto. This is followed by another 2-month rest. Measures of walking speed, distance, skill, confidence, as well as mood were obtained at least 3 times before any training, then monthly thereafter.

Participants to start with Precision Training. Participants train to walk over ground on 15 m straight hallway with obstacles they must step over, and targets they must step onto. Training was 5x/wk for 2 months, followed by a 2-month rest period. Participants then returned for Endurance Training 5x/wk for 2 months. Participants are trained 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. followed by another 2-month rest. Measures of walking speed, distance, skill, confidence, as well as mood were obtained at least 3 times before any training, then monthly thereafter.

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.

This is a 7 item, timed walking test. Participants perform each of the walking tasks and the time to complete each task is recorded. Maximum times are set for each task. An assistance category is assigned based on the walking aids used, with 1 being no aid and 6 being unable to complete the task. A score for each item is calculated as: Time x Assistance factor/Mean able bodied time. A composite (single) score is obtained by summing the scores for all 7 items. The maximum score for the scale is 2100 indicating that the participant was unable to complete any of the 7 tasks within the allowed time. A minimum score of 7 indicates that all tasks were performed with no aids and at the mean able-bodied time. Results are reported as a measure of change: Final score - initial score. A negative result indicates improvement.

Change from Baseline I to the end of the study (i.e., end of Rest Period II, which was ~8 months after the beginning of the study)

Change in Spinal Cord Injury - Functional Ambulation Profile (SCI-FAP) at 2 Months of Training Phase I

This is a 7 item, timed walking test. Participants perform each of the walking tasks and the time to complete each task is recorded. Maximum times are set for each task. An assistance category is assigned based on the walking aids used, with 1 being no aid and 6 being unable to complete the task. A score for each item is calculated as: Time x Assistance factor/Mean able bodied time. A composite (single) score is obtained by summing the scores for all 7 items. The maximum score for the scale is 2100 indicating that the participant was unable to complete any of the 7 tasks within the allowed time. A minimum score of 7 indicates that all tasks were performed with no aids and at the mean able-bodied time. Results are reported as a measure of change: Final score - initial score. A negative result indicates improvement.

Change in Spinal Cord Injury - Functional Ambulation Profile (SCI-FAP) at the End of 2 Months of Rest Period I

This is a 7 item, timed walking test. Participants perform each of the walking tasks and the time to complete each task is recorded. Maximum times are set for each task. An assistance category is assigned based on the walking aids used, with 1 being no aid and 6 being unable to complete the task. A score for each item is calculated as: Time x Assistance factor/Mean able bodied time. A composite (single) score is obtained by summing the scores for all 7 items. The maximum score for the scale is 2100 indicating that the participant was unable to complete any of the 7 tasks within the allowed time. A minimum score of 7 indicates that all tasks were performed with no aids and at the mean able-bodied time. Results are reported as a measure of change: Final score - initial score. A negative result indicates improvement.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Change in Spinal Cord Injury - Functional Ambulation Profile (SCI-FAP) at 2 Months of Training Phase II

This is a 7 item, timed walking test. Participants perform each of the walking tasks and the time to complete each task is recorded. Maximum times are set for each task. An assistance category is assigned based on the walking aids used, with 1 being no aid and 6 being unable to complete the task. A score for each item is calculated as: Time x Assistance factor/Mean able bodied time. A composite (single) score is obtained by summing the scores for all 7 items. The maximum score for the scale is 2100 indicating that the participant was unable to complete any of the 7 tasks within the allowed time. A minimum score of 7 indicates that all tasks were performed with no aids and at the mean able-bodied time. Results are reported as a measure of change: Final score - initial score. A negative result indicates improvement.

Change in Spinal Cord Injury - Functional Ambulation Profile (SCI-FAP) at the End of 2 Months of Rest Period II

This is a 7 item, timed walking test. Participants perform each of the walking tasks and the time to complete each task is recorded. Maximum times are set for each task. An assistance category is assigned based on the walking aids used, with 1 being no aid and 6 being unable to complete the task. A score for each item is calculated as: Time x Assistance factor/Mean able bodied time. A composite (single) score is obtained by summing the scores for all 7 items. The maximum score for the scale is 2100 indicating that the participant was unable to complete any of the 7 tasks within the allowed time. A minimum score of 7 indicates that all tasks were performed with no aids and at the mean able-bodied time. Results are reported as a measure of change: Final score - initial score. A negative result indicates improvement.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Participants walk for as far as possible in 6 min along a 25m hallway. Total distance walked in the time is measured. Results are calculated as : Distance walked at end of period - Distance walked at beginning of period.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Participants walk for as far as possible in 6 min along a 25m hallway. Total distance walked in the time is measured. Results are calculated as : Distance walked at end of period - Distance walked at beginning of period.

Participants walk for as far as possible in 6 min along a 25m hallway. Total distance walked in the time is measured. Results are calculated as : Distance walked at end of period - Distance walked at beginning of period.

Participants walk along a 14 meter path on a smooth floor at a comfortable pace. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change in 10 Meter Walk Test at a Self-selected Speed [10MWT(ss)] at the End of 2 Months of Rest Period I

Participants walk along a 14 meter path on a smooth floor at a comfortable pace. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Participants walk along a 14 meter path on a smooth floor at a comfortable pace. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change in 10 Meter Walk Test at a Self-selected Speed [10MWT(ss)] at the End of 2 Months of Rest Period II

Participants walk along a 14 meter path on a smooth floor at a comfortable pace. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Participants walk as quickly as they are able to along a 14 meter path on a smooth floor. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Participants walk as quickly as they are able to along a 14 meter path on a smooth floor. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Participants walk as quickly as they are able to along a 14 meter path on a smooth floor. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Participants walk as quickly as they are able to along a 14 meter path on a smooth floor. The middle 10 m is timed. Speed over 10 m is calculated as 10 m/Time. Results are calculated as: Final speed - initial speed.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Change in Walking Index for Spinal Cord Injury Version II Self-selected (WISCI-II ss) at 2 Months of Training Phase I

Participants are scored from 0 to 20 based on the walking aid they select to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change in Walking Index for Spinal Cord Injury Version II Self-selected (WISCI-II ss) at the End of 2 Months of Rest Period I

Participants are scored from 0 to 20 based on the walking aid they select to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Change in Walking Index for Spinal Cord Injury Version II Self-selected (WISCI-II ss) at 2 Months of Training Phase II

Participants are scored from 0 to 20 based on the walking aid they select to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change in Walking Index for Spinal Cord Injury Version II Self-selected (WISCI-II ss) at the End of 2 Months of Rest Period II

Participants are scored from 0 to 20 based on the walking aid they select to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Change in Walking Index for Spinal Cord Injury Version II Maximum [WISCI-II (Max)] at 2 Months of Training Phase I

Participants are scored from 0 to 20 based on the least amount of assistance/aid they require to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change in Walking Index for Spinal Cord Injury Version II Maximum [WISCI-II (Max)] at the End of 2 Months of Rest Period I

Participants are scored from 0 to 20 based on the least amount of assistance/aid they require to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Change in Walking Index for Spinal Cord Injury Version II Maximum [WISCI-II (Max)] at 2 Months of Training Phase II

Participants are scored from 0 to 20 based on the least amount of assistance/aid they require to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change in Walking Index for Spinal Cord Injury Version II Maximum [WISCI-II (Max)] at the End of 2 Months of Rest Period II

Participants are scored from 0 to 20 based on the least amount of assistance/aid they require to walk a distance of 10 meters. Walking aids and physical assistance provided are ranked on an ordinal scale from 1 to 20. A score of 0 indicates the participant is unable to walk 10 m, 20 indicates no aids are required to complete the task. Results are reported as Final score - Initial score. A positive result indicates that less assistance was required.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

A survey with 16 questions regarding the participants confidence in their ability to perform specific tasks requiring balance. Participants rate their confidence as a percentage from 0% (no confidence in their ability to perform the task) to 100% 9 completely confident in their ability to complete the task safely. Total score is calculated as: Sum of item scores/16 and is expressed as a percentage. Results are reported as Final score - Initial score. A positive result indicates a higher level of confidence in ability.

A survey with 16 questions regarding the participants confidence in their ability to perform specific tasks requiring balance. Participants rate their confidence as a percentage from 0% (no confidence in their ability to perform the task) to 100% 9 completely confident in their ability to complete the task safely. Total score is calculated as: Sum of item scores/16 and is expressed as a percentage. Results are reported as Final score - Initial score. A positive result indicates a higher level of confidence in ability.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

A survey with 16 questions regarding the participants confidence in their ability to perform specific tasks requiring balance. Participants rate their confidence as a percentage from 0% (no confidence in their ability to perform the task) to 100% 9 completely confident in their ability to complete the task safely. Total score is calculated as: Sum of item scores/16 and is expressed as a percentage. Results are reported as Final score - Initial score. A positive result indicates a higher level of confidence in ability.

Change in Activities-specific Balance Confidence Scale (ABC) at the End of 2 Months of Rest Period II

A survey with 16 questions regarding the participants confidence in their ability to perform specific tasks requiring balance. Participants rate their confidence as a percentage from 0% (no confidence in their ability to perform the task) to 100% 9 completely confident in their ability to complete the task safely. Total score is calculated as: Sum of item scores/16 and is expressed as a percentage. Results are reported as Final score - Initial score. A positive result indicates a higher level of confidence in ability.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Change in Center for Epidemiologic Studies - Depression Scale (CES-D) at 2 Months of Training Phase I

A 20 question survey to measure current level of depressive symptoms. The participant ranks their emotional state or actions for each question on an ordinal scale of 0 to 3, with 0 indicating rarely or never and 3 being most of the time. A minimum score of 0 indicates no depressive symptoms, and a score of 10 or greater is considered indicative of depression. The max score for the scale is 60. Results are reported as Final score - Initial score. A negative result indicates a lower level of depression.

Change in Center for Epidemiologic Studies - Depression Scale (CES-D) at the End of 2 Months of Rest Period I

A 20 question survey to measure current level of depressive symptoms.The participant ranks their emotional state or actions for each question on an ordinal scale of 0 to 3, with 0 indicating rarely or never and 3 being most of the time. A minimum score of 0 indicates no depressive symptoms, and a score of 10 or greater is considered indicative of depression. The max score for the scale is 60. Results are reported as Final score - Initial score. A negative result indicates a lower level of depression.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Change in Center for Epidemiologic Studies - Depression Scale (CES-D) at 2 Months of Training Phase II

A 20 question survey to measure current level of depressive symptoms.The participant ranks their emotional state or actions for each question on an ordinal scale of 0 to 3, with 0 indicating rarely or never and 3 being most of the time. A minimum score of 0 indicates no depressive symptoms, and a score of 10 or greater is considered indicative of depression. The max score for the scale is 60. Results are reported as Final score - Initial score. A negative result indicates a lower level of depression.

Change in Center for Epidemiologic Studies - Depression Scale (CES-D) at the End of 2 Months of Rest Period II

A 20 question survey to measure current level of depressive symptoms.The participant ranks their emotional state or actions for each question on an ordinal scale of 0 to 3, with 0 indicating rarely or never and 3 being most of the time. A minimum score of 0 indicates no depressive symptoms, and a score of 10 or greater is considered indicative of depression. The max score for the scale is 60. Results are reported as Final score - Initial score. A negative result indicates a lower level of depression.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

The strength of each of 8 major muscle groups (per side) in the lower extremities is graded using the standard manual muscle testing technique. Strength is graded from 0 (no muscle activity detected) to 5 (strength with normal range for the muscle group). Scores from all muscle groups are added to obtain the total score. The total score ranges from 0 (unable to produce any muscle activity in all 8 muscle groups bilaterally) to 80 (normal strength in all 8 muscle groups bilaterally). Results are reported as Final score - Initial score. A positive result indicates an increase in strength.

The strength of each of 8 major muscle groups (per side) in the lower extremities is graded using the standard manual muscle testing technique. Strength is graded from 0 (no muscle activity detected) to 5 (strength with normal range for the muscle group). Scores from all muscle groups are added to obtain the total score. The total score ranges from 0 (unable to produce any muscle activity in all 8 muscle groups bilaterally) to 80 (normal strength in all 8 muscle groups bilaterally). Results are reported as Final score - Initial score. A positive result indicates an increase in strength.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

The strength of each of 8 major muscle groups (per side) in the lower extremities is graded using the standard manual muscle testing technique. Strength is graded from 0 (no muscle activity detected) to 5 (strength with normal range for the muscle group). Scores from all muscle groups are added to obtain the total score. The total score ranges from 0 (unable to produce any muscle activity in all 8 muscle groups bilaterally) to 80 (normal strength in all 8 muscle groups bilaterally). Results are reported as Final score - Initial score. A positive result indicates an increase in strength.

The strength of each of 8 major muscle groups (per side) in the lower extremities is graded using the standard manual muscle testing technique. Strength is graded from 0 (no muscle activity detected) to 5 (strength with normal range for the muscle group). Scores from all muscle groups are added to obtain the total score. The total score ranges from 0 (unable to produce any muscle activity in all 8 muscle groups bilaterally) to 80 (normal strength in all 8 muscle groups bilaterally). Results are reported as Final score - Initial score. A positive result indicates an increase in strength.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Reflexes are elicited in standing by electrical stimulation (3 pulses) of the tibial nerve at the ankle using surface electrodes. Responses are recorded with surface electromyography (EMG) in µV.

Reflexes are elicited with electrical stimulation (3 pulses) of the tibial nerve at the ankle using surface electrodes. Responses are recorded with surface electromyography (EMG). Responses are typically recorded in standing.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Reflexes are elicited with electrical stimulation (3 pulses) of the tibial nerve at the ankle using surface electrodes. Responses are recorded with surface electromyography (EMG). Responses are typically recorded in standing.

Reflexes are elicited with electrical stimulation (3 pulses) of the tibial nerve at the ankle using surface electrodes. Responses are recorded with surface electromyography (EMG). Responses are typically recorded in standing.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Single-pulse TMS is applied over the motor cortex, and electromyographic responses are recorded in the tibialis anterior muscles on both legs.

Single-pulse TMS is applied over the motor cortex, and electromyographic responses are recorded in the tibialis anterior muscles on both legs.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Single-pulse TMS is applied over the motor cortex, and electromyographic responses are recorded in the tibialis anterior muscles on both legs.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Participants walk on a treadmill at a variety of speeds while we record surface electromyography from leg muscles and motion data from electrogoniometers place on the knees.

Participants walk on a treadmill at a variety of speeds while we record surface electromyography from leg muscles and motion data from electrogoniometers place on the knees.

Change from the end of Phase I training (measured at 2 months of Training Phase I) to 2 months of Rest Period I

Participants walk on a treadmill at a variety of speeds while we record surface electromyography from leg muscles and motion data from electrogoniometers place on the knees.

Participants walk on a treadmill at a variety of speeds while we record surface electromyography from leg muscles and motion data from electrogoniometers place on the knees.

Change from the end of Phase II training (measured at 2 months of Training Phase II) to 2 months of Rest Period II

Inclusion Criteria: spinal cord injury equal or more than 7 months prior able to walk at least 5 meters independently (can use walking aids and braces) injury level between C1 and L1 able to give informed consent able to attend training sessions 5x/week Exclusion Criteria: head injury cognitive of musculoskeletal impairments that preclude participation in walking training seizures or implants in the head that would preclude participation in experiments with transcranial magnetic stimulation

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Musselman KE, Yang JF. Spinal Cord Injury Functional Ambulation Profile: a preliminary look at responsiveness. Phys Ther. 2014 Feb;94(2):240-50. doi: 10.2522/ptj.20130071. Epub 2013 Oct 10.