I’ve lost count of the amount of times I’ve been asked “should I think about changing my mattress Graham?” This is a difficult one. Many people claim sitting all day causes low back pain but the evidence doesn’t really support this. Yes, if you already have low back pain, sitting all day will possibly make it worse, but sitting isn’t the cause of the back pain. Similarly, I’m not sure an old mattress will cause back pain, but if you already have it, it may well make it worse.
“expect to be faced with a bewildering array of options”
If you do decide it’s time to replace your old mattress, expect to be faced with a bewildering array of options.
The first website to pop up on google when I searched mattress types was The Better Sleep Council. Their website alone describes; interspring mattresses, hybrid mattresses, waterbeds, foam mattresses, pillow top mattresses, gel mattresses, airbeds, memory foam mattresses, latex mattresses and adjustable foundations.
Another quick search for ‘mattress for sale’ revealed a total of 240 million hits with prices ranging from 99p on eBay to £16,500 from John Lewis.
If an old mattress is likely to make your back pain worse, will a new mattress help relieve it? Possibly, but let’s have a look at what the evidence says.
“would any new mattress be better than an old one?”
In a study conducted by researchers from Oklahoma State University, 59 healthy subjects whose beds were at least 5 years old were given new beds with a medium-firm mattress. All the study participants reported less back pain, less shoulder stiffness and better sleep quality after 28 days of sleeping on the new beds. The main problem with studies like this however, is that there is no control group to compare the results with. Simply telling someone they were sleeping on a new mattress would possibly get the same positive results simply through the placebo effect.
Another problem with the above study is that it simply raises yet another question. Would any new mattress be better than any old one? While concluding that new bedding systems can significantly improve sleep the researchers acknowledged that previous studies comparing foam mattresses with coil spring mattresses and water beds returned mixed results.
In 2006, Dr James DeVocht and colleagues, looked at two measures of mattress quality in four top-of-the-line mattresses. First, they examined how well the mattresses distributed weight by measuring maximum pressure generated by volunteers lying on their back, and then measured the degree of spinal distortion when the volunteers lay on their side.
“aims of a mattress are to reduce maximum pressure and
reduce spinal distortion”
The results of the study showed that the two main aims of a mattress, to reduce maximum pressure and reduce spinal distortion, may be at cross purposes. They found that design features aimed at reducing spinal distortion may in fact increase the maximum pressure.
In addition, Dr DeVocht concluded that it’s not clear whether either factor, maximum pressure or spinal distortion, actually makes any difference in sleep quality.
Almost a decade earlier, in 1998 Buckle and Fernandes at the University of Surrey had found no association between maximum body contact pressure and subjective feelings of comfort. "It seems likely that subjective ratings of mattress comfort are dependent on a wider set of factors than contact pressure alone," they concluded.
In 2001 researchers, Park, et al, in South Korea, possibly got closer to an answer. They measured spinal curvature and distribution of body pressure on different mattresses, and then asked the subjects to evaluate the mattresses. They found that the participants preferred mattresses on which the spinal curvature when lying down was similar to that when standing and that participants were also more comfortable when the range of pressure distribution was narrow.
“when sleeping on mattresses that were deemed comfortable, their sleep efficiency and percentage of deep sleep were higher”
Five years after the 2001 South Korea study, some of the same research group went on in a new study to test the relationship of spinal curvature and pressure on sleep quality. The 16 participants lay on a mattress for 6 whole days and nights. Using a range of sensors, the researchers measured brain waves, eye movements, heart rhythm, and body temperature.
They found that when the participants slept on mattresses that they deemed ‘comfortable’, their sleep efficiency and percentage of deep sleep were higher.
So, what about firmness? Is there any truth in the myth that a firm mattress is better for back pain?
Orthopaedic surgeons certainly appear to think so. A survey of orthopaedic surgeons by Levy and Hutton in 1996 found that 95% of the surgeons questioned, believed that mattresses do play a role in the management of low back pain, and 76% of the surgeons recommended a firm mattress.
Mattress firmness is rated on a scale, developed by the European Committee for Standardisation, from 1.0 (firmest) to 10.0 (softest).
In contrast to the beliefs of the orthopaedic surgeons, a fairly robust 2003 double-blinded trial in Mallorca tested the notion that; the firmer the mattress the better, by randomly assigning 313 adults with chronic, nonspecific low back pain to either a firm mattress (2.3) or a medium-firm mattress (5.6).
“patients with medium-firm mattresses had better outcomes
than patients with firm mattresses”
After 90 days, the patients with a medium-firm mattress had better outcomes for pain in bed, pain on rising, and daytime low back pain, compared to the patients with a firm mattress.
Putting all these findings together, it would seem that a sensible recommendation would be to recommend mattresses that do not distort the spine, that distribute weight evenly, and are medium-firm in density.
Of course, few people can bring specialised test equipment with them to test for spinal curvature and weight distribution, but, as the Korean team pointed out, these factors correlate closely with the individual’s perception of comfort. So, the common-sense approach to selecting a mattress may still be the best advice. Lie on it and go with what feels comfortable to you.
Most people when selecting a mattress, firstly look at the price and if that’s OK, then press on it with their hands. If the mattress passes this ‘press’ test they then sit on it. If things are still looking positive they usually have a look round to make sure no one’s looking and then cheekily lie down on their back for a few seconds, roll over onto their side and then hurriedly get off before the salesperson sees them.
“take your time, lie on it and go with what feels comfortable to you”
Take your time. Even if you follow the guidelines and only keep your mattress for 7-10 years, with an average of 8 hours sleep per night, you will spend up to a whopping 29,200 hours lying on the mattress so take your time to get it right!
Sensible steps to buying a mattress
Determine your budget.
Read up on the different mattress types before you start shopping.
If you don’t feel your salesperson is knowledgeable or helpful, look elsewhere.
Lie on several different models in various positions.
Spend extra time in the position you usually sleep. It can take up to 15 minutes to relax enough to feel the true support of a mattress, so don’t rush it!
Sweet Dreams :-)