Imagine trying to exercise when you're paralyzed. It's very difficult to get your heart rate up when you're only able to use one half of your muscle mass. It's not surprising then, that cardiovascular disease is a major cause of death and injury in patients with spinal cord injuries. Now researchers are looking at whether exercise using electrical stimulation can make a difference.
Samantha Siu is a study participant. She says the bike it a little bit painfulm but she can tolerate it.
Paraplegic Samantha Siu hasn't been able to move her legs since she was injured in 1989. But she's getting ready to ride a special stationary bicycle. These electrodes on her legs enable her to pedal.
Janice Eng, PHD and Associate Professor, Physical Therapy at UBC says, "it's circulating the muscles to contract, and by doing that, that's where the benefits come in. Circulatory benefits, the increased muscle mass and load on the limbs can improve bone density."
But this type of stimulation may not be suitable for all spinal cord injury patients.
Eng says, "we've had some people who have some partial sensation and it's too painful, and some people's muscles just fatigue too much."
Then there's the matter of safety. A patient's oxygen usage and heart rate are closely monitored because, spinal cord injury patients typically have unstable blood pressure control.
Dr. Andrei Krassioukov, Research Associate at ICORD, says, "people with spinal cord injuries, their baseline or resting arterial blood pressures is usually very low. With this pressure, usually feel very fatigued. At the same time, any painful or non-painful stimuli will occur below the level of injury such as tight show or for example, electrical stimulation of muscle, their arterial blood pressure will jump to sometimes 200 or even 300MM HG systolic. It's a life threatening situation."
When she first started, Samantha could only ride for 4-5 minutes before her legs would spasm, now, she's able to ride for half an hour.
Samantha says it feels like she is working out. She thinks that it improves her spascicty a bit and its not as hard transferring into bed to car out of the wheelchair.
But can it help restore any lost motor function?
Eng says, "at this point, it's really important maintenance. There hasn't been found to be increasing motor recovery."
Samantha says, "it's good. It makes me have to exercise three times a week, otherwise, I wouldn't. I wouldn't do anything."
Experts say they still need a lot more data to make sure this type of stimulated exercise is safe and benefitial for spinal cord injury patients. The bikes are expensive. This one cost 16-thousand US dollars. It was donated to GF Strong Rehab Centre by the Rick Hansen Man in Motion Foundation to create a bike program in BC.
Wednesday May 24, 2006
