Intervention Study to Assess the Effects of Moderate and High Intensity Aerobic Training on Physical Capacity and Activity Level in Persons With Incomplete Spinal Cord Injury
Condition: Spinal Cord Injury
MeSH terms: Spinal Cord Injuries; Wounds and Injuries
Study type: Interventional

Summary: 
      The aims of this study are to assess the effects of medium versus high intensity 12-week
      adjusted training programs on physical capacity in persons with incomplete SCI, early after
      discharge from primary rehabilitation, and to investigate if the training program induces a
      more active lifestyle in terms of increased daily energy expenditure.
    

Detailed description: 
      Design:

      Randomized controlled trial.

      Participants:

      45 subjects, between 18 and 65 years of age, will be recruited with the following inclusion
      criteria: Traumatic spinal cord injury, incomplete lesions (classified as ASIA D), admitted
      to Sunnaas Rehabilitation Hospital for primary rehabilitation, and able to walk for 5 minutes
      on the treadmill (without assistive aids) at 4 km/hour.

      Subjects with cardiovascular diseases, progressive diseases and severe psychiatric conditions
      will be excluded.

      Procedures:

      The participants will be included after medical approval (by a specialist in physical
      medicine and rehabilitation) and before being discharged from primary rehabilitation. During
      the last week at the hospital, usually between 3 to 6 months post injury, a pre-test to
      examine physical capacity will be performed; maximal exercise test on a treadmill and
      six-minute walking test (Fig. 1).

      After the pre-test the participants will be randomized into one of three groups; Intervention
      Group I (high intensity training), Intervention Group II (medium intensity training), and a
      Control Group (treatment as usual, no additional training). To achieve balanced randomization
      (the compared groups should have about the same size), we will use block randomization. A
      computer random number generator will be used, with a block size of 15 and an allocation
      ratio of 1:1.

      The subjects in the training groups will have practical training at the hospital in how to
      perform moderate or high intensity training. They will be taught how to apply a heart rate
      monitor and how to use it during training sessions.

      At discharge from primary rehabilitation, and before start-up of the 12 week training
      program, the physical activity level (energy expenditure; kilo joule (kJ) · min -1) will be
      monitored by wearing a SWA for seven days in the home situation.

      After having completed the training program, the participants (including those in the control
      group) will wear the SWA in 7 days and return to Sunnaas Rehabilitation Hospital to repeat
      the physical capacity tests (post-test). This procedure will also be repeated at a follow-up
      one year after discharge from primary rehabilitation (12-months follow-up).

      All tests are performed under supervision of a physiotherapist, who has several years of
      experience in exercise testing. This physiotherapist is unaware of which of the three groups
      the patient the patient is recruited from (blind controlled trail).

      Interventions:

      Subjects in the two intervention groups will perform a 12 week individual training program,
      where 15 subjects will perform high intensity training and 15 subjects will perform a
      training program with moderate intensity training. Since literature indicates that SCI
      patients, on group level, do not improve their physical capacity after being discharged, our
      subjects will perform the training program in their home situation. To verify the intensity
      level during the training session, the participants have to wear a heart rate monitor. The
      heart rate will be stored for later analyses. Subjects in both training groups will be
      contacted, by telephone, during the first and the sixth week of the training program, to
      evaluate the training. A training log will be filled out by all the subjects (including those
      in the control group) during week 2-13.

      When comparing two training programs, one must be sure that the total amount of energy
      expended (total oxygen uptake) is equal. The calculation of the total oxygen uptake for the
      different training programs is based on the relationship between %HRmax and %VO2max,
      established by the American College of Sports Medicine (ACSM).

      Intervention group I - High intensity training The training program with high intensity will
      consist of two high intensity training sessions per week, using a treadmill or by outdoor
      walking/running. During these sessions the subjects will walk/run 4 times 4 minutes at an
      intensity of 85-95% of HRmax (interval training). Between the intervals, the subjects will
      have an active resting period (3 minutes), in which they walk at an intensity of 70% of
      HRmax. The subjects are free to choose which days of the week they conduct the training
      sessions, however, they must have at least one (resting) day in between.

      Intervention group II - Moderate intensity training The training program with moderate
      intensity will consist of three moderate intensity training sessions per week, using a
      treadmill or by walking outdoor. During these sessions the subjects will walk for 45 minutes
      at 70% of HRmax. The subjects are free to choose which days of the week they conduct their
      training session Control group The subjects in the control group (n=15) will have no
      additional training program, but left with treatment as usual. They will, however, be offered
      an individual training program after the one year follow-up test.

      Outcome measures

      Primary outcome measures:

      - Difference in VO2peak (change between pre-test and post-test 1) for both interventions
      groups and the control group.

      Healthy, untrained subjects show about 0.5 % increase in VO2peak for every (high intensity)
      training session. Assuming that persons with incomplete SCI show the same increase, we need
      about 15 subjects to detect a mean difference of 12 % in VO2peak. Sample size calculation is
      based on a standard deviation of 10 % with a significance level of 0.05 and power output of
      80%.

      Secondary outcome measures:

        -  Difference in VO2peak between intervention group 1 (high intensity) and 2 (moderate
           intensity), after having completed the training program (post-test 1)

        -  Changes in VO2peak (changes between pre-test, post-test 1 and post-test 2) for both
           interventions groups and the control group.

        -  Difference in VO2peak between intervention group I (high intensity) and II (moderate
           intensity), one year after discharge (post-test 2).

        -  Difference in daily energy expenditure (kilo joule (kJ) · min -1) between pre-test,
           posttest 1 and post-test 2

        -  Difference in daily energy expenditure (kilo joule (kJ) · min -1) between intervention
           group I (high intensity) and II (moderate intensity), one year after discharge
           (post-test 2).

      Data analyses and statistics:

      Oxygen uptake during the last 30 seconds of the maximal exercise test will be used to
      estimate peak oxygen uptake (VO2peak). VO2peak of pre- and post test (1, 2 and 3) will be
      compared to evaluate a possible training effect. From the SWA data, the daily energy
      expenditure (energy expended during one week divided by 7 days) before the training program,
      after the training program and one year after discharge, will be compared to evaluate a
      possible effect of the training programs on the subjects' physical activity level.
    

Intervention name(s): High intensity training; Moderate intensity training
Intervention type(s): Other; Other
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Treatment
Keywords: spinal cord injury; physical capacity; energy expenditure; training