Stepper Aerobic Training on Fitness, Disability, Inflammation and Thrombosis in Stroke Patients

In Taiwan, there are 220,00 stroke survivors and each year, 10,000 new suffers causing impairment in daily activities. This is the leading cause of disability and consumes 4.5 billions of National Health Insurance yearly. More than half of them become hemi-paretics and hemi-plegics. Stroke leads to the adverse combination of reduced functional capacity and increased energy demands to perform routine activities Thereby, physiologic fitness reserve is diminished. Aerobic fitness is low in stroke survivors. Among ambulatory patients suffering from hemiparetic stroke, the VO2peak is approximately half that of age-matched individuals , a level that is near the minimum range required for activities of daily life. It may limit their ability to perform everyday activities and cause further complications, such as cardiopulmonary de-conditioning, muscular atrophy, joint stiffness, or even learned nonuse.

Many patients are discharged from neurorehabilitation focusing on motor control and ADL (activity of daily life ) training, while aerobic fitness training is neglected, especially in non-ambulatory patients. Randomized exercise training studies using a wide variety of modalities and protocols have demonstrated an 8~23% improvement in VO2peak after 2-6 months of training . However, most research recruit patients with hemiparesis who have mild-to-moderate gait impairment . No specific training protocols has been adequately studied or can be suggested for hemiplegic patients. It is difficult for them to partake in aerobic exercise, like walking or biking. There is a need to develop a new aerobic exercise module suitable for the patients, especially for those with ambulation difficulty resulted from severe paralysis.

In the current investigation, a semi-recumbent stepper with constant power design will be adopted as training modality. It accommodates motor function deficits by providing trunk and distal limb support . In addition, semi- recumbent stepper uses bilateral reciprocal movement of the arm coupled with the opposite leg, which allows for a push and pull motion.

Aerobic fitness training has been proposed as a beneficial approach for people with stroke. Taking part in fitness training could have a range of other benefits important to people with stroke such as improving cognitive function, improving mood, and quality of life, and it could reduce the risk of recurrent stroke . In the present investigation, the outcome measurement will not only include cardiopulmonary fitness and the degree of daily activity dependency, but also prognostic biomarkers, thrombotic and inflammatory state.

It is well-documented that exercise training has an anti-thrombotic effect . Increased physical activity and cardiorespiratory fitness are associated with a reduced risk of fatality from cardiovascular diseases. Moreover, increased studies have demonstrated that regular moderate-intensity physical activity is associated with health benefits, even when aerobic fitness (e.g., maximal oxygen uptake, VO2max) remains unchanged . For sedentary persons at risk for cardiovascular disease, adopting a moderately active lifestyle can induce important health benefits, such as reducing prothrombotic factors and lipid peroxidation , increasing fibrinolytic activity and high-density lipoprotein levels , etc. One of the present investigation aims to understand whether 20~25 sessions of aerobic training at moderate intensity will induce these favorable adaptations that could contribute to decreased risk for ischemic event.

This is a prospective randomized controlled study. Eighty stroke sufferers with unilateral weakness will be enrolled in Chang Gung Memorial Hospital at Linkuo. They will be randomized into two groups: combined training (CT) and usual rehabilitation (UR). Participants in the CT group will receive supervised aerobic training at moderate intensity in addition to usual neuro-rehabilitation, in which motor control and task-oriented ADL training are the major contents. Patients in the UR will undergo usual neuro-rehabilitation only. The aim of the present research is to evaluate the efficacy of an aerobic training program at moderate intensity for a total of 20~25 sessions using a semi-recumbent stepper with constant power design. Pre- and post-training measurement includes (I) cardiopulmonary fitness, (II) daily activities dependency, (III) coagulation and fibrinolysis profile. [the 1st year] (IV) monocyte subsets and its interaction with platelets [the 2nd year]. (V) Systemic inflammation, platelet activation and prognostic biomarker：C-reactive protein, soluble P-selectin, asymmetric dimethylarginine, Lipoprotein-Associated Phospholipase A2, etc. [the 3rd year]. Venous blood will be sampled two times before and after rehabilitation.

Hopefully, this clinical investigation will establish the model of incorporating aerobics in the hemiplegic patients following stroke, and its efficacy for clinical application.