Treadmill training improves fitness reserve in chronic stroke patients

Objective: To investigate the hypothesis that treadmill training will impro ve peak fitness, while lowering the energy cost of hemiparetic gait in chro nic stroke patients. Design: Noncontrolled exercise intervention study with repeated-measures an alysis, Setting: Hospital-based senior exercise research center. Participants: Twenty-three patients (mean age +/- standard deviation [SD] 6 7 +/- 8yr) with chronic hemiparetic gait after remote (>6mo) ischemic strok e. Intervention: Three 40-minute sessions of treadmill exercise weekly for 6 m onths. Main Outcome Measures: Peak exercise capacity (Vo(2)peak) and rate of oxyge n consumption during submaximal effort treadmill walking (economy of gait) by open circuit spirometry and ambulatory workload capacity before and afte r 3 and 6 months of training. Results: Patients who completed 3 months of training (n = 21) increased the ir Vo(2)peak +/- SD from 15.4 +/- 2.9mL . kg(-1) . min(-1) to 17.0 +/- 4.4m L . kg(-1) . min(-1) (p <.02) and lowered their oxygen demands of submaxima l effort ambulation from 9.3 +/- 2mL . kg(-1) . min(-1) to 7.9 +/- 1.5mL . kg(-1) . min(-1) (p =.002), which enabled them to perform the same constant -load treadmill task using 20% less of their peak exercise capacity (62.3% +/- 17.2% vs 49.9% +/- 19.3%, p <.002), Gains in Vo(2)peak and economy of g ait plateaued by 3 months, while peak ambulatory workload capacity progress ively increased by 39% (p <.001) over 6 months. Conclusions: Treadmill training improves physiologic fitness reserve in chr onic stroke patients by increasing Vo(2)peak while lowering the energy cost of hemiparetic gait, and increases peak ambulatory workload capacity. Thes e improvements may enhance functional mobility in chronic stroke patients.