So if you think catching up on sleep on the weekend is enough to undo your week of poor sleep-- you're wrong. A new study in Men's Health magazine proved this by tracking the groginess, problem-solving abilities, motor skills and reaction times of participants. The participants slept for six hours a night for six consecutive nights and then were allowed three nights of ten-hours of sleep. Researchers say that while the ten hour nights reduced sleepy feelings, other functions did not return to normal. Researchers say the increased amount of sleep on the weekends only partially reverses the effects of a restricted weeknight sleep schedule.