If heavy lifting is in your job description, you could benefit by new research at Ohio State University.
Researchers there measured the amount of oxygen reaching the muscles in the lower back as workers lifted heavy boxes onto conveyor belts. They found that as the day progressed, less oxygen reached the muscles, less oxygen meant more muscle fatigue and more muscle fatigue meant a greater risk of back injury. Even more so as the day wore on.
So, the study suggests that if workers who do heavy lifting are given longer and more frequent breaks as the day goes on, they can avoid back injuries and employers can avoid sick days.