It's no secret that sleep is crucial during the intensive growth phase of adolescence. Yet studies have shown that teenagers' average sleep per night has declined by 50 minutes over the past 25 years.

While the causes of this decrease are often hard to pinpoint, sleep researchers at the Hôtel-Dieu Hospital in Paris have found one way to remedy the problem: newer, bigger mattresses.

Professor Damien Léger, director of the Centre du Sommeil et de la Vigilance, the Parisian hospital's sleep research center, partnered with the founder of the European Sleep Center, Doctor François Duforez, to study the effects of high-quality bedding on teenagers' sleep.

The two researchers were motivated by recent studies on the question, which show that French teenagers are not getting their recommended eight to nine hours of sleep per night. According to the country's National Institute of Statistics and Economic Studies (INSEE), subjects aged 15-19 slept just seven hours and 37 minutes per night on average. Nearly one third of the study's participants had accumulated a "sleep debt," while 17% said they were dissatisfied with their sleep. More troubling, 7% of the teenagers in the study reported taking sedatives to help them sleep.

"The quality and quantity of sleep depend among other factors on the synchronization of the body's internal clock with a sleeping and waking schedule. But teenagers have a tendency to delay going to bed, particularly at the start of the week when they feel less tired. And on the weekends they tend to shift their sleep schedules and sleep more (for example, 15-year-olds sleep one hour and 41 minutes longer on average when they don't have school the next morning). This de-synchronization can be the cause of a sleep debt in the mid to long term," the INSEE study states.

A high-quality mattress to help make up for lost sleep

While making sure your 16-year-old goes to bed at the same time every night is no easy task, Léger and Duforez have found one way parents can ensure they are doing what they can for their teenagers' sleep: give them a large, unused mattress.

The researchers found that teenagers' mattresses were often too small to accommodate their rapid growth. Moreover, they were often worn out or of poor quality, having been inherited from another family member.

Specifically, the study showed that teenagers could gain an extra 31 minutes of sleep by upgrading to a newer, larger mattress, which would reduce the time they spend falling asleep by half. Teenagers would gain 22 extra minutes of slow sleep phases, which contribute to physical recovery and growth, and 8 minutes of REM sleep, which is essential to memorization and learning. Finally, teenagers with a new, high-quality mattress also have less waking episodes lasting more than 15 seconds.