Do Back Belts Protect from Injury? Another Notch in the Research
Whether back belts protect workers from injury remains a hotly debated issue around the world. Many studies have suggested there's no advantage to wearing a belt. These studies have raised a number of questions. Are back belts being worn properly? Is one belt more effective than others? Are the belts helpful for all loads or just certain types and amounts?
An occupational therapist in Taiwan teamed up with another researcher to take a fresh look at this issue. The researchers decided to measure trunk muscle activity using two different breathing techniques while lifting. One method was to breathe in and hold the breath while lifting. The other was to breathe out while lifting. The belt used was carefully controlled. Belt pressure was adjusted to three different settings. All three belt pressures were included in the study.
The idea was to look at the effect of belt pressure on breathing and trunk muscle activity during repetitive lifting. Would different belt pressures result in different muscle activity? Would belt pressure affect the stomach muscles? Would different breathing methods affect back muscle activity? This study was different from past studies because the researchers looked at two kinds of pressure: belt pressure and pressure from holding the breath.
In this study, the belt did reduce the use of back muscles. The researchers thought this positive result might be due to the kind of belt used and the way it was used. An elastic belt with a high width and four semi-rigid bars was carefully fitted by an occupational therapist. Researchers also found that the stomach muscles helped out the back muscles during lifting.
Whether back belts prevent back injuries remains in question. Many studies have been done, with varying results. This study showed that controlling both air volume and belt pressure while lifting benefits the back. It may be that belt type and proper usage contribute to a better result. More studies are needed before the question of back belts is resolved.
Yung-Hui Lee, PhD, and Su-Mai Kang, OTR. Effect of Belt Pressure and Breath Held On Trunk Electromyography. In Spine. February 1, 2002. Vol. 27. No. 3. Pp. 282-290.