In an exciting development in bioengineering, electrical stimulation is being used for the first time to evoke a whole-body response, writes Danielle Barron
Busy modern lifestyles have meant that the nation has gotten progressively, well, lazy. Which of us hasn't dreamed of a method that would allow us to lose weight while we sat on the sofa, instead of pounding the treadmill or the footpath?
Amazingly, such a device now exists but, unfortunately, you won't be using it as you enjoy your favourite soaps any time soon. However, it may just provide the key to the successful treatment of morbidly obese patients.
Efforts to create such technology began in 1999 when Dr Louis Crowe approached Dr Brian Caulfield, of the UCD School of physiotherapy and Performance Science with the novel idea of using muscle stimulation to elicit cardiovascular exercise.
At the time, the US Food and Drugs Administration (FDA) had muscle stimulation listed on its website as one of its "sham" treatments for weight loss.
"They didn't list that many, but they had specifically said that any muscle stimulation treatment marketed for weight loss is a sham treatment and there is no evidence," says Caulfield. "We saw this as a challenge."
Abdominal stimulators have been extremely popular since they were first introduced and have led to the development of similar systems for arms and thighs.
"They tone your muscles and make you hold yourself a little better so your body appearance will change but you don't lose weight," explains Caulfield.
The team began to investigate but the novelty of the idea meant that they initially hit an impasse. "We were trying to get the body as a whole to respond by increasing the metabolic rate. Nobody had ever done this before," recalls Colin Minogue, technical director with Bio Medical Research (BMR), in Galway which carries out research and design on medical products.
His company has been involved with the project from the start.
A breakthrough for the team came when Crowe decided trying to emulate shivering could be a way to approach the challenge.
"The way humans generate heat is by shivering and shivering occurs at a certain frequency. It's essentially rapid rhythmic muscle contraction that brings your core temperature up," explains Caulfield.
The team was able to achieve the same effect with muscle stimulation using existing technology, however, the only problem was it wasn't very comfortable.
Another of the challenges facing the team was providing current in a specific location and direction, rather than a blanket stimulation of a particular area, says Caulfield.
"We figured that if we put an array of electrodes, instead of just two, perhaps eight or even more, on a muscle or body region that could be switched on and off at various points, these were more effective in depolarising a nerve or getting a muscle contraction," he says.
"They were also more effective in targeting the delivery of the stimulus to the exact tissues where we wanted," says Caulfield.
Having provided a more targeted and efficient muscle contraction of larger amounts of tissue with more comfort, the team was then able to develop a particular application of the technology that would elicit a cardiovascular exercise effect.
A group of sedentary adultswas given the system to use at home for six weeks and it was found that their cardiovascular exercise capacity improved considerably, by 10-15 per cent. Their capacity for physical exercise also improved, says Caulfield.
"Not only were we able to elicit this response, we were able to do it in a very safe manner. It was comfortable and they found it very tolerable," he adds.
It was also found to be safe and effective in a group of heart failure patients, again producing an increase in their exercise tolerance and cardiovascular exercise capacity.
The technology has now been successfully used to train top-level athletes, including international middle-distance runners and professional rugby players.
Dr Madeline Lowery of UCD's department of electrical, electronic and mechanical engineering is working on building computer models of nerve and muscle activity. Predicting what will happen with different combinations of electrodes presents a particular challenge, says Lowery.
"It's difficult because a lot of things we are dealing with are unknown parameters. The neuro muscular system is so complicated and there's still an awful lot we don't know about it," she says.
"From a bioengineering point of view, it's very, very exciting. For the first time electrical stimulation is being used to evoke a whole-body response," adds Minogue.
According to Caulfield, the health benefit of the system is that it will allow aerobic exercise to be delivered to those who need it but are not in a position to engage in it.
Also involved in this application of the project is Dr Donal O'Shea, consultant endocrinologist at the weight management clinic in St Columcille's Hospital in Loughlinstown, Bray, Co Wicklow.
The system represents an extremely useful and novel approach to dealing with the problem of obesity, says O'Shea.
"There are only three drugs available for obesity and they effectively reduce calorie intake. There's nothing available other than actual physical exercise that helps the other side of the equation in weight loss, which is energy burn," he explains.
According to O'Shea, the system has the potential to be far more effective than the available drugs and with the added benefit of making the patient cardiovascularly fit.
The system will not replace weight-bearing exercise, rather it will provide a bridge for those unable to exercise, says O'Shea. "It will start the ball rolling for these patients. Once patients start losing weight and see that there is a way forward, they are very encouraged."
With Ireland facing an obesity epidemic, the groundbreaking system will be a more-than-welcome addition to the tools for tackling obesity, says O'Shea.
"Despite all the publicity and despite the obesity taskforce report, there are more patients being referred to our clinic and also paediatric obesity clinics. The problem is continuing to get worse and worse. It's not going away," he says.