More than a third of the senior managers interviewed said they worked more than the 48-hour week limit set by the European Working Time Directive. Their average working week clocked in at 58 hours, while a very tired few admitted to 100 hours.
"The results of this survey are shocking," says Peter Mooney of ELAS.
The effect on morale, increased stress and simple fatigue could be costing the economy millions.
"Signing an opt-out to enable staff to work more than 48 hours a week is one thing, but to work such long hours routinely has a negative effect," said Mooney.
ELAS's own research a few weeks ago revealed a growing trend for "long weekend syndrome", where large numbers of employees call in sick either side of the weekend. Of the companies interviewed, 67% said Monday was the most popular staff sick day, while 23% said Friday was the most popular.