In 2003, Hess and Hecker conducted a review of research related to stretching at work for injury prevention. Based on the three best-known studies they reviewed, stretching did not result in any meaningful or statistical reduction in WMSDs. Furthermore, there has been a tremendous amount of research on stretching and injury reduction in sports. The results have been similar.
Stretching and Sports
Studies have shown that static stretching prior to an athletic event will decrease muscular power (Marek, S.M., et al., 2005), torque (Evetovich, T.K., et al., 2003), maximum force output (Bacurau, R.F., et al., 2009), vertical jump height (Young, W. and Elliott, S., 2001), sprint speed (Nelson, A.G., et al., 2005), agility (McMillian, D.J., et al., 2006) and maximal strength for up to 1 hour (Fowles, J.R., Sale, D.G., and MacDougall, J.D., 2000). Static stretching prior to an athletic event will lower endurance performance and increase the energy cost of running during a 30-minute run (Wilson, J.M., 2010).
In 2004, Thacker, et al., completed a systematic review of the literature related to the impact of stretching on sports injuries. They conclude, “There is not sufficient evidence to endorse or discontinue routine stretching before or after exercise to prevent injury in competitive or recreational athletes.”
More recently, in 2009, Goggins, et al., completed an exhaustive review of the literature related to case studies that reported benefits of ergonomics programs and control measures. The researchers proposed the following relationship between ergonomic controls and the estimates of effectiveness (based on results from case studies).
The image shows that controls that rely on behaviors, such as site-wide workplace stretching programs, have limited overall effectiveness (5 percent to 20 percent). Coupled with the fact that there is no meaningful or statistical reduction in WMSDs associated with site-wide workplace stretching programs, it seems that the benefit of the financial investment is marginal, at best.
According to McGowan, “To reduce or eliminate exposure, effective ergonomic practices need to be addressed. Risk factors need to be quantified and the root causes need to be identified. By using engineering controls, practices and methods it is then possible to reduce or eliminate the exposure.” This method appears to have a greater effectiveness, both from a cost and risk reduction perspective, he says.
Cost-Effectiveness of Engineering Changes
Some engineering improvements, on a per project basis, could cost pennies compared to a stretching program, says McGowan. For instance, purchasing new tooling can range from $100 to $300; improved workstation design can cost up to $1,000; and, material handling devices can cost up to $5,000. There are a lot of workstation improvements that can be implemented for little money, such as repositioning part bins to prevent overextending or twisting body positions, adjusting the height of the workstation so that the user is aligned properly, changing the orientation and position of control buttons on machinery or providing carts to move heavy loads can all have meaningful impacts.
