A team of UCD researchers conducted a series of experiments last week on a muscle stimulation device they had invented, which causes aerobic exercise using a Neuromuscular Electrical Stimulation Exercise (NMES). These experiments were carried out on a parabolic flight to determine whether the device was suitable for use by astronauts in space.
It had previously been thought impossible to produce an aerobic exercise effect using a muscle stimulation device, but Principal Investigator, Dr Brian Caulfield, explains that this is exactly what the team did.
“We have developed a new form of delivering the electric current into the tissues, which is called multi-path stimulation. It involves using very complex pulse shapes and pulse pathways delivered via an array of electrodes rather than the standard approach to stimulation, which is to use pairs of electrodes and very simple pulse shapes. We also don’t tighten the muscle and hold it, we pulse the muscle, tighten and let it go a few times per second. Doing that causes a demand for oxygen, and the only way you can get more oxygen to the muscle is your heart pumping more blood to the muscle, like it would be if you were walking on a treadmill – by doing this, we have been able to mimic aerobic exercise.”
The device, made with the Galway-based company, Bio-Medical Research, was not originally intended for astronauts, “we didn’t develop this technique for astronauts, there’s a very small number of astronauts in the world, in the grand scheme of things they’re not that important; this was developed to meet a healthcare and societal need. There’s a very large number of people out there who are sick because they don’t exercise, there are conversely a large number of people who cannot exercise because they are sick … for example people with arthritis who can’t do weight-bearing exercises … astronauts fall into the category of people who can’t exercise – when they’re in space they can’t exercise due to zero gravity.”
Masters student involved with the project, Lorenza Cafolla, explained that the testing during the week was carried out “to see whether it would be any use for anti-gravity projects and potentially in the International Space Station for astronauts in space to give them a modality of exercise rather than shifting up heavy machinery like a treadmill or the bicycles in the gym, this stuff is really bulky and space is at a premium up there.”
The next stage in the project may be either another set of parabolic flights to refine the experiment set-up and have the subject strapped standing up instead of sitting down. After that, a bed-rest study is expected to be carried out as it will enable the researchers to understand how people react to long-term zero gravity. According to Dr Caulfield, “bed-rest is not a million miles from what zero-gravity does to you – [you] don’t have the gradience of pressure on different parts of your posture and no loading on your boning structure.”
The project started in 2006 and providing it passes all further tests, will be expected to go up to the International Space Station in two to three years.