Washington: People sacrifice sleep during the workweek to make time for other demands, then snooze longer on the weekends to recoup that lost sleep.
New research has shown that even a few days of lost sleep can have adverse effects, including increased daytime sleepiness, worsened daytime performance, an increase in molecules that are a sign of inflammation in the body, and impaired blood sugar regulation.
The last two could be partially responsible for why sleeping less negatively affects health in other ways and shortens the lifespan.
Though many people believe they can make up sleep lost during the workweek by sleeping more on the weekend, it's unknown whether this "recovery" sleep can adequately reverse these adverse effects.
To help answer this question, researchers led by Alexandros N. Vgontzas of the Penn State University College of Medicine, placed 30 volunteers on a sleep schedule that mimicked a sleep-restricted workweek followed by a weekend with extra recovery sleep.
At various points along this schedule, the researchers assessed the volunteers' health and performance using a variety of different tests.
The researchers found that the volunteers' sleepiness increased significantly after sleep restriction, but returned to baseline after recovery sleep.
Levels of a molecule in blood that's a marker for the amount of inflammation present in the body increased significantly during sleep restriction, but returned to normal after recovery.
Levels of a hormone that's a marker of stress didn't change during sleep restriction, but were significantly lower after recovery.
However, the volunteers' measures on a performance test that assessed their ability to pay attention deteriorated significantly after sleep restriction and did not improve after recovery.
This last result suggests that recovery sleep over just a single weekend may not reverse all the effects of sleep lost during the workweek.
The study is published in the American Journal of Physiology-Endocrinology and Metabolism.