Your caffeine use throughout the day could be contributing to poor sleep quality at night — meaning that you need more coffee the next morning, and the cycle continues. A study in 2013 looked at how consuming caffeine zero, three, or six hours prior to bedtime affected sleep quality, and discovered something surprising. While caffeine consumed just as the subjects went to sleep obviously made them wakeful and restless, coffee doses six hours before — say, at 4 p.m. when they were going to bed at 10 p.m. — kept them awake too.

"Caffeine taken six hours before bedtime has important disruptive effects on sleep," the researchers wrote in the study. This, they explained, "provides empirical support for sleep hygiene recommendations to refrain from substantial caffeine use for a minimum of six hours prior to bedtime." Check out your usual coffee and tea schedule and cut out the afternoon doses if they come within that six-hour window.

Instead of using caffeine to keep you awake, sleep experts recommend going in the other direction and using daytime sleep to make your night sleep more refreshing. "A 20-minute nap is long enough for you to receive the restorative benefits of the first couple of stages of sleep," Northwestern Medicine writes. However, you need to be judicious in your nap choices. "Be careful: napping longer than 20 minutes as you may enter a deeper sleep phase, and waking up in the middle of that can lead to grogginess. Also avoid napping later in the day as it may disrupt your sleep cycle, and don’t rely on naps to make up for a full good night’s sleep." A short nap can boost your alertness and make you feel more refreshed overall.

What's causing you to wake up feeling tired and in need of a caffeine boost? The National Sleep Foundation suggests looking at your patterns of wakefulness during the night. "Many people trudge out of bed for a drink of water or to use the bathroom at night. But if you’re up repeatedly and awake for more than 20 minutes in one night, you need to examine your sleep habits," they advise. That kind of wakefulness means your sleep overall will be less restorative and you'll feel fatigued and sleepy in the morning.

To improve sleep wakefulness, monitor what you're putting into your body in the afternoons. "Avoid caffeine, alcohol, and big meals as well as power down your electronic devices at least an hour before bed," says the National Sleep Foundation.

The question of restorative sleep can be answered, for many of us, by better sleep hygiene. 'Cleaning up' our sleep involves getting rid of disruptions and potential disturbances, and Brigham Health explains that temperature is particularly important. "Keep your bedroom cool," they advise. "There’s some variability in preferred sleeping temperatures, but the aim should be between 65 and 70 degrees Fahrenheit. Find the temperature that’s right for you, and set your thermostat to that degree." Many studies have found that over-heating in the night negatively impacts sleep quality, leading to sluggish wake-ups.

This may run counter to the work-hard-play-hard ethos of being young, but a regular sleep schedule could reduce your reliance on caffeine for wakefulness on weekdays. "Making up" sleep on weekends by sleeping in after a late night isn't actually helpful to your routine; maintaining a regular sleep schedule throughout the week is healthier. Yep, that means going to bed at the same time every night. If you do want to wake up late, "try not to vary by more than 30 to 45 minutes, even on the weekend,” sleep neurologist Aparajitha Verma told WebMD.

The time at which you wake up has a big role in how refreshed you feel. Everybody experiences four different stages of sleep overnight — stages one, two, three and REM or rapid eye movement sleep — that repeat once every 90 minutes or so. REM is the period of sleep in which you dream. "The secret to refreshing sleep is to wake up naturally after a sustained period of REM," Dr. Neel Burton writes for Psychology Today. "There is wisdom in the old saying that "one hour’s sleep before midnight is worth two after.""

Use this knowledge to your advantage with a sleep alarm app that monitors your sleep cycles through collecting data about your movements in the night. Apps like Sleep Cycle and Sleep Better use information about how deeply you're sleeping to pick an opportune moment to wake you — removing the horrible sluggish feeling you get when you're jerked out of dreaming sleep. Set a half hour parameter in the morning, and the app will wake you up at the best, lightest point within that limit. Tired feelings begone.

You don't have to give up your morning coffee if you don't want to — but if you're only in need of a caffeine bump to get you moving, natural sleep hacks might help you feel awake and alert in other ways. Result? More money to spend on something else, and a more harmonious sleep cycle.