The title of this blog post should probably be the title of my PhD thesis, as it sums up what I (and other people working in this specific field) have been trying to do over recent years. Near Infrared Spectroscopy (NIRS) offers us an opportunity to gain real-time information about what’s going on inside our bodies whilst we exercise, and it doesn’t require any needles or anything nasty of that sort – so it’s pretty amazing really!
But how does it work?
Firstly, light of wavelengths in the ‘near-infrared’ range is special, because when you shine it into the body, it doesn’t get completely absorbed by haemoglobin molecules in the blood (as is the case at lower wavelengths), and it doesn’t get completely absorbed by water molecules (as is the case at higher wavelengths) – so in the near-infrared range we have an ‘optical window’, where some of the light we shine in will come back out and be detected.
The production of small devices such as this has meant that this very exciting technique can be expanded to use in a wide-range of exercise settings to investigate a variety of questions: evaluation of physical fitness; the effect of warm-up and cool-down on performance; and the metabolic effects of exercise training. The pool of research in exercise science using portable NIRS is growing, which is great news.
Hopefully those of you who have been to see us at the Science Festival will agree that this is a very interesting technique, and will be able to support my claim that we are able to get information about what’s happening in your muscle when you exercise without causing any pain or discomfort at all! If you don’t believe me, come down and have a go!
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| The electromagnetic spectrum, showing the position on near-infrared light, at wavelengths just higher than visible light |
Secondly, within this near-infrared ‘optical window’, haemoglobin which is bound to oxygen acts differently to the light than haemoglobin that is not bound to oxygen. So we can tell how much of the haemoglobin in the muscle is carrying oxygen. It is very interesting to see how this figure changes when the muscle is working, when a greater amount of oxygen is required for the muscle to contract.
For some years now, NIRS has been a technique used in hospitals to monitor the oxygen levels in the muscles and brain of patients. However, most of the NIRS devices available are quite bulky, and not really suitable for use in a sports setting. The device I’ve been using during my studies is called the Portamon, and it is completely wireless and very small – see for yourself in this photo!
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| Since this device is smaller than my phone, it's very easy to transport around, and very easy to attach to the body of an athlete. |
Hopefully those of you who have been to see us at the Science Festival will agree that this is a very interesting technique, and will be able to support my claim that we are able to get information about what’s happening in your muscle when you exercise without causing any pain or discomfort at all! If you don’t believe me, come down and have a go!
That’s all for now, I’ll be back soon with the first set of results from the festival,
Catherine
That was a very informative post, Catherine. With that, a lot of people will know what NIRS is, and how it can be of help to their respective fields. Agriculture and pulp industries are also using this technology to enhance the quality of their products. The capability of NIRS to detect and measure the amount of raw material and substance is definitely helpful for product test. And the field of medicine also makes use of NIRS for some of their non-invasive test and therapy.
ReplyDelete[George Melcher]