Objectives
To evaluate training induced effects of constant-load treadmill aerobic exercise (T-AEX) versus circuit-based task-oriented exercise (Task-CT) on cardiac risk and metabolic outcomes.

Participants
Thirty-two chronic stroke survivors who completed inpatient/outpatient rehabilitation, could follow 2-step instructions, and walk with or without assistance.

Interventions
Participants were randomized to complete 30 sessions of T-AEX or Task-CT over a 10-week period. The T-AEX sessions involved 30-min of body-weight supported treadmill walking with the speed and incline adjusted to reach 40-60% of heart rate reserve (HRR). During Task-CT, participants performed 2 times 3 circuits of 3 different task-oriented exercises while maintaining heart rate 30-50 beats above resting. 

Outcome(s)
Cardiac risk score (CRS) was computed using the Framingham risk model. Blood samples were taken to evaluate changes in lipid profile (triglycerides, total cholesterol / HDL), and inflammation associated with cardiovascular disease (C-reactive protein, CRP). Maximal oxygen uptake (VO2max) was recorded on the total-body recumbent stepper. 

Results
Average workloads maintained during T-AEX and Task-CT corresponded to 5320% and 4914% of HRR, respectively. Baseline CRS was relatively low in both groups and no significant changes were observed. A significant time effect was observed for CRP (F(1,30)=4.02, p=0.023). Compared to baseline and follow-up measurements, CRP was reduced after T-AEX (1.24mg/l; 0.30mg/l) and Task-CT (0.95mg/l; 1.79mg/l). Although participants in both groups had clinically meaningful changes in VO2max (T-AEX=7/13 and Task-CT=6/19), time effects were only observed post T-AEX ( 2.83.9 mlmin-1kg-1; p=0.024).  

Conclusions
Both exercise interventions led to clinically meaningful changes in aerobic fitness and inflammatory markers of cardiac risk.

The Effects of Task-oriented Circuit Training and Treadmill Aerobic Exercise Training on Cardiac Risk and Metabolic Outcomes in Chronic Stroke Survivors