Out of 1,000 survey respondents, 42 percent said that they were expected to be ever more productive at work, according to the study by the Bertelsmann Foundation and health insurer Barmer GEK.
One in three said that they didn't know how they would fulfil all of the demands made of them in the workplace.
And half of employees said they had no influence at all over the amount of work they were expected to complete, while 40 percent felt they had no input into their goals.
“Management can significantly influence this performance culture and create a healthy work environment using realistic goals,” Bertelsmann Foundation board member Brigitte Mohn said in a statement.
The study authors suggested that employees should have regular, realistic conversations with their bosses about their goals at work.
And they pointed out that making overambitious demands of workers led to dangerous habits, like nicotine consumption or turning to medication, or even relaxing of important safety and quality standards at work.
“We need a culture in business that recognises health as a precondition for economic success and supports it,” Barmer GEK chairman Christoph Straub said in a statement.
Workers' goals ought to be achievable within their contracted hours, study author and psychologist Dr Anja Chevalier of Cologne's German Sports University said.
Fellow author Professor Gert Kaluza, of the GMK Institute for Health Psychology in Magdeburg, added that it was important for workers to develop a sense for their own limits in order to achieve their maximum potential in the long term.
“The study shows a dangerous trend that's being accelerated by the digitisation of the working world,” Annelie Buntenbach of the German Trade Union Federation (DGB) said.
“The promise of new freedoms is being converted into its opposite, when only results count and unachievable goal diktats are being set.”
Buntenbach added that “it's important to bring the relationship between working time and work performance back into the equation, so that working time doesn't become devalued” - something she said would require more and better communication between workers and employers.
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