Ah, sleep. Why is our most precious recharging resource so scarce in our busy, modern lives?

We all know the excuses: demanding schedules, social lives and screen time. Sometimes it's subconscious, but we're all making decisions to do these things instead of getting the sleep we need.

ABC News Chief Medical Correspondent Dr. Jennifer Ashton walked us through some of the most common myths about sleep to set the record straight.

Myth 2: If I don't get enough sleep during the week, I can make it up over weekend

FALSE: "Our body's circadian rhythms are finely tuned and connected to regular sleep behavior. And our hormones, our metabolism, all kinds of neurotransmitters, are all tied into those circadian rhythms and when we're sleeping," Ashton said.

Weekend schedules often vary from our weekdays, but it's best to not alter your sleep schedule by more than an hour on either end.

"Locking down a sleep schedule is not just important for infants and babies; it's really important for adults as well," Ashton said.

Myth 3: I might be tired the next day, but there are no long-term effects of not getting enough sleep

Myth 5: You get better sleep when your bedroom is cold

TRUE: If you often get up the middle of the night, it might be your body waking you up because you're sweating or too hot.

Ashton keeps her room at a cool 66 degrees year-round for a restful and undisturbed night of sleep, but you can adjust your levels to whatever feels comfortable for you.

Myth 6: Bedtime starts when you get in bed

FALSE: You should unplug an hour before you want to go to bed. Put your phone down, turn off the TV and get off the computer. Even dimming the lights in your house will signal to your brain that it's time to go to sleep.

Treat yourself to a warm bath or shower, drink chamomile tea or read a good book.

Then by the time you get into your bed, "Your brain should say I'm here to sleep," Ashton said.

Myth 7: Getting exercise during the day will help you get better sleep

TRUE: If you exercise for 30 to 60 minutes during the day, you'll be more tired by the time you get into bed.

Ashton also recommends meditation at some point in the day as another way to ensure you fall asleep more easily.

Myth 8: It's OK to use sleeping pills

FALSE: "I can't emphasize this enough -- there are no prescription sleeping pills that are approved for long-term use," Ashton said.

While they can be safe and effective in the short term, they affect your brain chemistry and are harmful to use long term.

Myth 9: You can't get too much sleep

FALSE: Too little or too much sleep is bad for you.

"Too much sleep sends different messages to our body ... maybe we're sick, maybe we're injured," Ashton said.

"It disrupts our circadian rhythms, our metabolisms. Don't be lured into this false sense of security that more is better -- when it comes to sleep, that's not true," she added.

Myth 10: Naps disrupt your sleep