Women are generally two-thirds the size of men by weight, height, strength and muscle mass, but are they really the weaker sex when it comes to lifting heavy objects?
Yes and no, LTC Mary Laedtke, Ph.D., told an audience at the American Industrial Hygiene Conference and Expo (AIHce) this week in San Diego. Women generally cannot lift as much as men, but often, men shouldn't do as much lifting or as heavy a lift as they are often asked to do by their employers. A recent exercise at a U.S. military facility shows that there aren't many women or men who could do what Uncle Sam recently asked a group of soldiers to do.
Laedtke, who is a researcher at the U.S. Army Center for Health Promotion and Preventive Medicine at the Aberdeen Proving Ground in Maryland, spoke to a relatively small audience, which was interesting since the topic of the session was "Women's Health Issues in the Americas" and there are so many women in the workforce now. Laedtke showed the audience a short film of six soldiers, four female and two male, who removed a prototype stretcher out of an ambulance and carried it a few feet away. As the soldiers muscled the stretcher out of the ambulance or "cracker box," as Army personnel refer to them, they nearly dropped it. Even under the most optimal conditions, very few soldiers could lift and carry the stretcher for a long distance, Laedtke noted.
The stretcher was what is known as an LSTAT - Life Support for Trauma and Transportation - a transportable ICU bed that can be taken to the front lines of battle. "With all the equipment and batteries," noted Laedtke, "it weighs 175 pounds … and it's empty." Add a 200-pound soldier, with all of his gear, and it weighs more than 375 pounds, she added. Add on the gear carried by the soldiers doing the carrying, the fact that terrain is rarely smooth, the fact they might be dodging bullets, and the possibility that the soldier in the stretcher will be moving around, and it becomes a bad ergonomic situation.
She offered scenarios created by researchers examining the practicality of trying to use the LSTAT "as is," with no wheels, small hand grips, and fully loaded with equipment and batteries. The best-case scenario is a 102-pound female carried by a team of four large male soldiers from a helicopter (40 inches high) to a place a short distance away. The worst-case scenario was a 200-pound male soldier picked up at a height of 50 inches and carried a far distance by a team of two female and two male soldiers.
For the "best case" scenario - even with the smaller amount of weight lifted, the lower height from which it was lifted, the fact that large males were doing the lifting and the short distance traveled - those soldiers carrying the LSTAT would have exceeded the recommended lift weight of 56 pounds per person by 13 pounds. The other lift, with a heavy patient, a mixed gender lift team and higher lifts over longer distances, would have exceeded the recommended lift weight by nearly double.
The U.S. Army spent a considerable amount of money on the LSTAT, and didn't want to junk the equipment if possible. Suggestions were made to make the LSTAT stationary, to allow the components to be removed and carried separately, to change the four-person lifting team to a six-person lifting team, provide shoulder harnesses, change the hand grips, and add legs and tires.
So what did the Army do? It added legs and wheels to the LSTAT, so that lifts are not so high and the soldiers don't have to carry it.
"When you say let's make the job better for women, what you're really doing is making it better for everyone," Laedtke told the audience. "One size does not fit all, whether you are male or female."