Obviously, pulling an all-nighter will leave us off our game the next day. That performance-zapping effect applies not just to all-nighters, but any night where we're skimping on sleep, though—especially when it comes to meeting our gym goals, according to a new study presented this week at the annual SLEEP 2016 conference. (And, BTW, all the caffeine in the world won't help you get back on track.)
The small study conducted by the American Academy of Sleep Medicine looked at how a pattern of sleep deprivation would impact the athletic performance of elite athletes. The researchers had 12 cyclists restrict their sleep to just four hours a night for three consecutive nights. Then they had them perform a series of tests on a bike each day.
They found that after the three days of sleep deprivation, the cyclists' athletic performance took a serious hit as compared to their normal cycling skills. Specifically, the researchers found that the cyclists' max energy expenditure dropped by four percent, their maximum aerobic power decreased by three percent and the time it took them to reach exhaustion went down by over 10 percent—a big deal when you're trying to set a PR. The cyclists' peak heart rate also decreased after the sleep deprivation. (But Will One Night of Poor Sleep Affect Your Workout?)
In other words, skimping on your sleep at night will do exactly what you would expect to your performance: tank it.
According to the researchers, further studies are needed to determine how making a habit of increasing your sleep each night might impact your performance in spin class, but as a general rule of thumb, assume that more sleep is better when it comes to crushing your gym goals. (And find out What Really Happens When You're Sleep Deprived.)