Workers who lift for a living need to take longer or more frequent breaks than
they now do to avoid back injury, according to a new study at Ohio State
University. The study also suggests that people who are new on the job need to
take breaks even more often than experienced workers, and that the risk of
injury is higher at the end of a work shift.
People who participated in the study lifted boxes onto conveyor belts for eight
hours, while researchers measured the amount of oxygen that was reaching the
muscles in their lower back. The oxygen level indicated how hard the muscles
were working, and whether they were becoming fatigued. The study, which
appeared in a recent issue of the journal Clinical Biomechanics, is the first
to examine what happens to muscle oxygenation over a full workday.
Despite the fact that the study participants were performing the same job at
the same pace all day, their back muscles needed more oxygen as the day went
on. Taking a half-hour lunch break helped their muscles recover from the
morning's exertion, but once they started working again, their oxygen needs
rose steeply and kept climbing throughout the afternoon.
AplusA-online.de - Source: European Agency for Safety and Health at Work