Managers are suffering because of the "harmful" culture across British industry, working around 46 days of unpaid overtime a year, going to work while ill and suffering increased levels of stress and depression, according to a new report.
Research among 1,000 managers painted a "bleak" picture of bigger workloads, more ill-health and low levels of job satisfaction.
The Chartered Management Institute said its study also showed a number of "negative" management styles had emerged over the past few years, including overly bureaucratic or authoritarian.
The problems were holding back economic growth, hitting productivity and leading to business decline, the report warned.
Compared with 2007, managers were working longer hours, more likely to go to work while sick and increasingly suffering from stress and depression, the study found.
Most of the managers questioned said their organisation had been restructured in the past year, while almost half had seen compulsory redundancies.
The average manager now works around 46 days' unpaid overtime a year, six more than in 2007, because of increased workloads.
Howard Hughes, of health company SimplyHealth, which helped with the study, urged employers to encourage their staff to care for their health.
The report's author, Professor Les Worrall, of Coventry University, said: "The scale and impact of change over the last five years has been staggering as all of our key measures from the survey have deteriorated markedly since 2007.
"What is more worrying is that there seems to be no sign of economic conditions getting better - we are in for a worrying time if these trends persist into the future."