Superman's bicycle helps paraplegic patients keep fit and healthy

8 June 2008

A new type of exercise equipment can help prevent serious lifestyle illnesses in paraplegic patients. The Ergys 2, which was partly developed at the Norwegian University of Science and Technology (NTNU) in Trondheim, was first designed for the American actor Christopher Reeve.

Christopher Reeve, who played Superman in films, became a quadrapelgic after a riding accident and financed the development of the rehab equipment, in the hopes of improving his own health. But that didn’t quite happen, and the actor died of heart failure when he was just 52 years old. Nevertheless, his efforts gave the world’s spinal injury patients a useful piece of rehabilitation equipment. 

Patients who are unable to walk after a spinal injury have a poorer quality of life and a shortened lifespan than their non-paralysed counterparts. Sitting passively in a chair makes people susceptible to weight and digestion problems, lower bone density, diabetes, and last but not least, heart and circulation problems.

“It’s the circulation problems that are the most difficult for them, and it’s circulation problems that kill them”, says Jan Hoff, a professor of medicine at NTNU. But it doesn’t have to be that way. A new type of exercise equipment, combined with a new training plan, makes it possible for spinal patients to exercise themselves back to health — at least as far as the heart is concerned.

In an exercise study completed last year, patients who were paralysed from the chest or waist down experienced an average increase in their oxygen uptake by 25% and in their heart pumping volume by fully 37% after just eight weeks of training.

Never before has so much improvement or such impressive results been documented in this patient group.


Ready for interval training on the Ergys 2: Terje Roel is paralysed as a result of a spinal injury. Researcher Berit Brurok is readying Terje for a demonstration of the arm and leg cycle. Photo credit: Vegard Eggen/Gemini J.

Not just a stationary bicycle

The Ergys 2 is a stationary training bicycle, where the patient’s legs and feet are strapped to a leg holder and pedals. Electrodes are then fastened to the patient’s thigh and seat muscles, and electrical impulses trigger the muscles to contract and relax.

The impulses are computer controlled to guarantee the best possible effect. Even though it may seem like artificial training, it is real enough as it’s the patient’s own muscles that are working. And it is movement that demands energy: the blood flow increases, and the pulse goes up. The exercise has an effect on muscle mass, muscle strength, oxygen uptake and the heart’s pumping volume.

Hard workouts, few repetitions

But it’s not enough to focus on the legs and buttocks, if this kind of training is going to make a real difference. The more muscle groups that are involved, the greater the blood flow, and the greater the benefits for the heart.

NTNU researchers supplemented the Ergsys 2 with an arm cycle, intended for patients who can use their arms without help. The patients who participated in the training study were also able to simultaneously exercise their shoulders, arms, rump and legs, in a high-intensity interval 4 x 4 pattern. That translates to four minutes of hard exercise followed by three to four minutes of easier training, with the entire procedure repeated four times per session, three days a week.

NTNU’s Professor Jan Hoff developed this interval approach several years ago, along with his colleague Jan Helgerud. He uses this interval technique for most types of physical training.

“Hard workouts, few repetitions. There is no other training approach that gives better results in improving oxygen uptake or muscle strength than that”, he says.

A preventative approach

Never before has research documented such a significant effect on the heart and circulation in patients with spinal injuries, as the study has shown. There has been relatively little research overall on spinal patients and exercise, in terms of what kinds and how much exercise actually give beneficial results.

The patients in this study were so out of shape when they started that they were unlikely to reach a normal level. But Hoff doesn’t think it’s an impossible goal. “We really don’t know, but there’s no reason to believe that the improvements will stop where they are now”, he says.

Hoff doesn’t want to speculate on the implications of his research on the treatment of Norwegian patients paralysed from spinal injuries.

“We’re researchers, not therapists” he says. “But it’s clear that what we’re doing has consequences, both for Norway and for the world. And that gives us a great opportunity to prevent lifestyle related illnesses”.

Unplugged?

Under Hoff’s guidance, Berit Brurok conducted the study for her master’s thesis in exercise physiology. Brurok is continuing her work in this area as a part of her PhD research, in cooperation with Dr Tom Tørhaug at St Olavs Hospital in Trondheim.

Because the Ergys 2 is expensive, and also requires assistance to use, the researchers are looking to see if the results from the study can be transferred to other activities such as in a wheelchair or without electricity.

If they succeed, it could mean a better quality of life and a longer life for many people. In Norway alone there are 5000 spinal injury patients, while in the USA that number may be closer to 500,000.  

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