According to a new study, almost 76% of workers feel tired "most days" which affects their productivity during the day's work.

Virgin Pulse teamed up with Vielife to discover how feeling tired and sleepy affects their work performance and why they keep on getting the same problem, Huffington Post reports.

Published in a report entitled, "Asleep on the Job: The Causes and Consequences of Employees' Disrupted Sleep and How Employers Can Help," 1,100 U.S.-based employees answered assessments to investigate on their sleep disturbances and how it affects them at their jobs.

"If it's a really, really bad night with sleep, I'll tend to find myself like not drifting off, but like maybe losing concentration big time at work, where all of sudden I'm thinking about something non-work related and not really quite sure how I got there," one participant told researchers.

Results show that 75.6% feel tired frequently, at least once or twice a week. 40% of the workers admitted to sleeping during working hours at least once a month, 15.2%  are guilty of sleeping at work at least once a week, and 2.2% reported that they doze off frequently at work, about once or twice daily.

According to respondents, mental activities, worry, physical needs, and environmental noise prompted sleep disturbances.

"I guess if I've had a particularly stressful day, I tend to, you know, when it's time to go to bed, I'll kind of lay there and just mull it over, and really dwell on things," a participant shared.

Participants also stated what sleep disturbances have caused them, such as a huge drop on their energy levels, "fuzzy headed thinking", irritability, less patience, and stress.

"If you don't have enough sleep, or you don't have enough energy to deal with it, I think it just stresses you out all the more," another participant told researchers.

Participants were able to deal with this problem by changing their sleep environment, engaging in exercise, healthier diet, and modifying their "middle of the night thinking."