The Exact Time You Should Go To Bed

By Melissa Walker at Yahoo Health

While everyone's sleep needs are a little bit different, there is a simple trick to help you figure out your perfect bedtime. 

Blackout blinds, white-noise machines, prescription medication - we'll try a lot of tricks to get a full night's sleep. Studies show that sleep is critical for our moods, our minds, and our overall health, and we just plain feel better after a good rest. But how do we know if we've gotten that ever-elusive "right amount" of sleep? It turns out that there's a science to doing it well.

"There is absolutely a right time to go to bed," says Michael Breus, PhD, a board-certified sleep specialist and author ofGood Night: The Sleep Doctor's 4-Week Program to Better Sleep and Better Health. That right time is unique to each individual Breus tells Yahoo Health, but there's a formula that will help you figure out your own magic hour.

"The average sleep cycle is 90 minutes long, and the average human has five of those sleep cycles per night," explains Breus. That means we all need around 7.5 hours of shuteye - he says the 8-hour advice touted everywhere is a myth. (While 7.5 is a good center gauge for most people, everyone's sleep needs are slightly different, with some people needing more or less sleep than others.) 

So how to get your 7.5 in? "Work backward from your wake-up time," says Breus. "That's socially determined by when you have to get up to get to work, get the kids ready, all those external factors." So if you have to get up by 6:30 a.m., count back 7.5 hours and recognize that your bedtime should be 11 p.m.

"Follow that bedtime for 10 days in a row," says Breus, "and you'll begin, quite naturally, to wake up a few minutes before your alarm clock sounds." It's key, he stresses, to be consistent - that's how the human circadian system functions best. "Sleeping in on the weekends causes your system to shift and makes you want to go to bed later and wake up later," he says. That's one reason why Monday mornings can feel so difficult - Breus calls that bedraggled feeling "social jet lag."

But what about people who say they can't fall asleep at 11 p.m., for example? "It's all about the wake-up time," insists Breus. "I don't care if you can't fall asleep at 11 p.m. initially. If you are consistent about getting up at 6:30 a.m. every morning, your body will adjust."

Here are three easy things you can do to improve your zzs: 

1. Set a nighttime alarm. If you have to go to bed at 11 p.m., set your alarm for 10:30 p.m. and it'll remind you to get ready for bed so you'll meet your nocturnal deadline. If you're consistent about waking time, a morning alarm will become unnecessary, says Breus.

2. If you work with a computer all day, try f.lux. It's a program that makes the brightness of your screen adapt to the time - warm at night, and brighter, like sun, during the day. It's especially great for late-night work, because if you check your computer at midnight, you don't want to be looking at a bright screen. (You can use the app for your phone too.)

3. As soon as possible after you wake up, get into the sunshine. Whether that means reading the newspaper out on the patio or standing by a window as you sip your coffee for 15 minutes, soaking up a bit of sunshine will reset your circadian clock and help your body's natural sleeping-waking rhythm.

How Your Bedtime Affects Your Workout

From Sarah Jacoby at 

Forcing yourself to work out is one thing, but forcing yourself to wake up early and thenwork out? That is truly asking a lot. But, new and encouraging research suggests that, for some of us, sleeping in might be the best way to prep for exercise.

In the small study, published earlier this month in Current Biology, 20 field hockey players were sorted into groups based on their sleep and wake-up times, both during the week (when they're at the mercy of an alarm) and on the weekend (when they're more able to follow natural rhythms). Nearly half of them were considered to have the "intermediate" circadian phenotype, meaning they tended to wake up around 9:30 a.m. and fall asleep around midnight on the weekends. Another 25% were sorted as early risers, and the remaining 25% were the night owls.

Then, everyone had to perform a cardio endurance test at six different times of day. Overall, participants did their best on the test near the end of the day (at 4:00 and 7:00 p.m.) and their worst at the very beginning (7:00 a.m., yikes). However, personal bests for the cardio tests were dependent on participants' circadian phenotypes — especially the late risers, whose performance steadily improved as the day went on.

Even if you're not a field hockey player, this suggests that your personal best can be affected by the timing of your workout and your natural sleep-wake cycle. (Speaking of sleep, previous research has shown that doing cardio in the morning and strength training later in the day can improve the quality of your sleep.)

Although squeezing in an early morning jog is certainly better than not doing anything, this means it won't necessarily be the most productive workout. If your schedule allows, you could get better results if you time your sweat sessions based on your own internal schedule. So, for you night owls, try planning for an after-work sweat session and save the morning for some snoozing. Doesn't that sound more pleasant anyway?