Body-weight supported treadmill training improves cardiovascular fitness and walking endurance early after stroke

Blikk på forskning i Fysioterapeuten 10/2014.

Fagartikkel

Blikk på forskning utarbeides i samarbeid med Journal of Physiotherapy (Australia), som trykker forskningspresentasjonene under betegnelsen Critically appraised Papers, CAPs.

Synopsis: Summary of: MacKay-Lyons M, et al (2013) Dual effects of body-weight supported treadmill training on cardiovascular fitness and walking ability early after stroke: a randomized controlled trial. Neurorehabil Neural Repair. DOI: 10.1177/1545968313484809. [Prepared by Marco YC Pang, CAP Editor.]

Question: Does body-weight supported treadmill training improve cardiovascular fitness and walking function in people with subacute stroke compared with overground gait training?

Design: Randomised, controlled trial with concealed allocation and blinded outcome assessment.

Setting: Stroke rehabilitation unit in Canada.

Participants: Adults within one month of a first ischaemic stroke, and ability to walk 5 m with or without walking aids or standby assistance were key inclusion criteria. A key exclusion criterion was contraindication to maximal exercise stress testing. Randomisation of 50 participants allocated 24 to the experimental group and 26 to the control group.

Interventions: Both groups were trained 5 days per week for 6 weeks and then 3 days per week for a further 6 weeks. The experimental group underwent body-weight supported treadmill training. The target exercise intensity and duration was set at 60–75% of  the peak oxygen consumption rate (peak VO2) for a minimum of 20 minutes. The control group was instructed to walk overground at comfortable, self-selected speeds for the same duration. The two groups were given home programs (3 days per week) after the 12-week supervised training.

Outcome measures: The primary outcomes were peak VO2, 6MWT, and overground walking speed. The secondary outcomes were Berg Balance Scale, and Chedoke-McMaster Stages of Recovery (CMSR) score. Outcomes were measured at baseline, posttraining, and at 6- and 12-month follow-up.

Results: 37 participants completed the study. The experimental group improved more than the control group for measures of peak VO2, 6MWT, and CMSR foot score. At the end of the 12-week intervention period, the experimental group had significant improvement in peak VO2 (by 4.2 ml/kg/min, 95% CI 2.5 to 5.9) and CMSR foot score (by 1.0 point, 95% CI 0.3 to 1.7) whereas the control group had no significant improvement in these variables. The experimental group also had significantly more improvement in the 6MWT (by 89.7 m, 95% CI 54.4 to 125.0) than the control group (by 36.8 m, 95 %CI 4.2 to 69.4). These effects were largely preserved at 12-month follow-up. There were no betweengroup differences for other outcomes.

Conclusion: A bodyweight supported treadmill training program is effective in improving cardiovascular fitness and walking endurance in people after stroke.

Commentary

Regaining the ability to walk is a common goal priority after stroke such that gait-related activities receive the most attention during stroke rehabilitation (Latham et al 2005). Body-weight supported treadmill training (BWSTT) has received much attention as a modality to improve walking outcomes, but its superiority over other means of gait training has not been consistently demonstrated (Duncan et al 2011, Moseley et al 2005). Low fitness levels may compound mobility limitations after stroke. There is an important interaction between neuromotor impairments and cardiovascular fitness as the capacity to meet the high metabolic demands of walking is reduced (Tang et al 2007). Historically, therapy during stroke rehabilitation provided minimal aerobic challenge (MacKay-Lyons et al 2002), but now it is known that early exercise interventions can improve fitness and walking ability (Stoller et al 2012). The randomised trial conducted by MacKay-Lyons and colleagues contributes novel and important evidence in a number of ways. First, they demonstrated that BWSTT was effective in concurrently addressing cardiovascular fitness and walking ability in individuals with limited ambulatory capacity. It was also conducted within the first month post-stroke, capitalising on the window of opportunity for neurological recovery. Finally, it demonstrated that gains were retained long after completion of training. Given the presence of post-stroke neuromotor impairment and cardiovascular deconditioning, and the interaction between these factors on functional mobility, it is important to develop interventions that effectively and concurrently address these issues and capitalise on the early time window of opportunity to maximise benefit. The results of this trial offer promising evidence supporting the use of individualised and progressive BWSTT among people in the early stages of stroke recovery.

Ada Tang, School of Rehabilitation Science, McMaster University, Canada

References

Duncan PW et al (2011) N Engl J Med 364: 2026–2036.

Latham NK et al (2005) Arch Phys Med Rehabil 86 (Suppl 2):S41–S50.

MacKay-Lyons MJ et al (2002) Arch Phys Med Rehabil 83:1378–1383.

Moseley AM et al (2005) Cochrane Database Syst Rev 4:CD002840.

Stoller O et al (2012) BMC Neurol 12: 45.

Tang A et al (2009) Neurorehabil Neural Repair 23: 398–406.