To investigate the postural control factors influencing the automatic (reflex-controlled) and attentional (high cortical) factors on dual task.
We used a dual task model to examine the attentional factors affecting the control of posture, subjecting test subjects to vibration stimulation, one-leg standing and verbal or nonverbal task trials. Twenty-three young, healthy participants were asked to stand on force plates and their centers of pressure were measured during dual task trials. We acquired 15 seconds of data for each volunteer during six dual task trials involving varying task combinations.
We observed significantly different sway patterns between the early and late phases of dual task trials, which probably reflect the attentional demands. Vibration stimulation perturbed sway more during the early than the late phases; with or without vibration stimulation, the addition of secondary tasks decreased sway in all phases, and greater decreases in sway were observed in the late phases, when subjects were assigned nonverbal tasks. Less sway was observed during the nonverbal task in a sequential study.
The attentional and automatic factors were analyzed during a sequential study. By controlling the postural control factors, optimal parameters and training methods might be used in clinical applications.
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To examine the cardiorespiratory responses of patients with spinal cord injury (SCI) paraplegia using a motor driven rowing machine.
Ten SCI patients with paraplegia [A (n=6), B (n=1), and C (n=3) by the American Spinal Injury Association impairment scale] were selected. Two rowing techniques were used. The first used a fixed seat with rowing achieved using only upper extremity movement (fixed rowing). The second used an automatically moving seat, facilitating active upper extremity movement and passive lower extremity movement via the motorized seat (motor rowing). Each patient performed two randomly assigned rowing exercise stress tests 1-3 days apart. The work rate (WR), time, respiratory exchange ratio (R), oxygen consumption (VO2), heart rate (HR), metabolic equivalents (METs), and rating of perceived exertion (RPE) were recorded.
WR, time, VO2, and METs were significantly higher after the motor rowing test than after fixed motor rowing test (p<0.05). HR after motor rowing was significantly lower than fixed rowing (p<0.05).
Cardiorespiratory responses as VO2, HR and METs can be elicited by the motor rowing for people with paraplegic SCI.
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