By Corrie Pikul
An All-Nighter vs. 2 Hours of Sleep
It's 3 a.m., and you need to get up at 5 a.m. for your flight or your work shift or your conference. The clock is forcing you to make a decision: Curl up in bed for two hours of shut-eye or power through the next day? While your instinct and your drooping eyelids may urge you to take a nap, this might make you feel even worse than if you hadn't slept at all, says Michael A. Grandner, PhD, research associate at the Center for Sleep and Circadian Neurobiology at the University of Pennsylvania. "If you get less than 4 hours, there's a good chance that you'll wake up in slow-wave sleep, which can leave you disoriented, irrational and extremely irritable," Grandner says--in other words, like a hot mess. He explains that our bodies are pretty resilient and can function reasonably well without sleep once in a while, so you'll be able to chug through the day even if your mind will be a little fuzzy (this means catching a plane wouldn't be a problem, but driving a car would).
Best advice: Fire up the coffee pot, stay busy until your natural circadian rhythm kicks in and then hang in there until your normal bedtime.
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Sitting vs. Smoking
As you're no doubt sick of hearing by now, sitting is bad for your health. A group of Australian researchers recently tried to find out just how bad by analyzing data from a giant lifestyle survey with 11,247 participants over the age of 25. Every daily hour of sitting while watching TV was associated with an 8 percent higher risk of death, they reported in the October issue of the British Journal of Sports Medicine (they controlled for the effect of exercise, diet, obesity and other relevant factors). "Watching one hour of TV above age 25 may be about as lethal as smoking one cigarette," says J. Lennert Veerman, PhD, a senior research fellow at the University of Queensland, who led the study. Keep in mind that smoking causes many cancers--lung, throat, kidney, bladder, pancreas, stomach and cervix--as well as acute myeloid leukemia, and Veerman adds that it's also highly addictive. Then again, prolonged sitting has been associated with higher risks of heart disease, diabetes and obesity-related illness.
Best advice: Lighting up might be worse for us as individuals, but sitting down may well cost more lives overall. "While smoking rates are going down, almost everyone watches quite a bit of TV," says Veerman. He recommends limiting couch time to two hours per day or night.
Alcohol vs. Coffee Before Bed
Both are infamous sleep disruptors, but they act in opposite ways, says Allison T. Siebern, PhD, CBSM, clinical assistant professor and the associate director of the Insomnia and Behavioral Sleep Medicine Program at Stanford University School of Medicine. Caffeine tricks your body into thinking that you aren't sleepy, Siebern explains. As soon as the effect wears off, you'll crash--which in this case isn't such a bad thing. However, if one glass of wine leads to two or three, you may initially find yourself drowsy, but once the alcohol starts to leave your system, Siebern says, you could start snoring, slip into nightmares, drench the blankets in sweat, feel your head pounding or experience dry mouth. So the post-meal espresso is likely to decrease the quantity of your sleep, while the wine will insidiously tamper with the quality of it. Caffeine may also take 4 to 7 hours--that's basically all night--to leave your system if you drink a potent cup or are particularly sensitive to it. Alcohol has a shorter half-life, Siebern says, which means it will leave the body in about 3 to 4 hours. If you can wait that long before going to bed, then cheers to you.
Best advice: Choose the coffee if you could use a few hours of alert time to get things done at home; the wine if you could use some more time to catch up with your friends. Skip both if you need to be up early tomorrow.
Exercising on an Empty Stomach vs. a Full One
What's the problem with running (or spinning, or stair-climbing, or Zumba-ing) on empty? We asked Heidi Skolnik, MS, CDN, FACSM, a nutritionist with a private practice who's worked with dancers at the Juilliard School as well as players with the New York Knicks. First, Skolnik wants to know why you didn't have anything to eat. Saving calories?: "You'll probably be so hungry later that you'll eat even more," she says, adding that she sees this over and over with her female clients. Think of this snack as fuel: Skolnik says research supports the idea that having something in your tank will help you work out harder, which will then help you burn even more calories. Worried that it's bad for your body?: Skolnik explains that working out immediately after a big meal will cause blood to be diverted to your muscles instead of your digestive system. But while she agrees this can be uncomfortable, she says it's not physically harmful. Too busy? Skolnik gets that, but she strongly advises against making it a regular habit. You'll be too weak and hungry to get the maximum benefit from your workout, and you'll be setting yourself up for a binge session later that night. And if your workout involves strength-training, your could go into catabolic mode and start breaking down muscle. Isn't that enough motivation to stock your gym bag with energy bars?
Best advice: Eating too much will probably result in an unpleasant workout, but not eating anything can be bad for your workout, your diet--and--your long-term health.
Energy Drink vs. Soda
You may not realize this, but most energy drinks have just as much sugar as soda: A 12-ounce can of Red Bull and a 12-ounce can of cola both have about 9 teaspoons. So they're even on that score, but the smallest can of Red Bull also has 80 mg of caffeine, which is double what's in a can of Coke. And it may do a lot more than perk you up: A 2006 New Zealand study revealed that caffeine combined with the sugar in that Red Bull may temporarily inhibit the body's ability to burn fat. More alarmingly, since 2009, 5-Hour Energy (which is sugar-free, but has about 215 mg of caffeine) has been mentioned in 90 filings with the U.S. Food and Drug Administration, including more than 30 that involved serious or life-threatening injuries, reports The New York Times. While it's true that most people can handle one regular-size can without ill effects, the high levels of caffeine involved in multiple servings could result in dangerous, even life-threatening, effects on blood pressure, heart rate and brain function, according to a 2010 review in the The Mayo Clinic Proceedings. Most energy drinks also contain special ingredients that are said to boost physical or cognitive performance, like taurine (Red Bull), ginseng (Monster), and glucuronolactone (5-Hour Energy). But two researchers who conducted a review of these ingredients' effects concluded that there isn't much evidence that any of these will make you faster, smarter, or better in any way.
Best advice: Energy drinks will rev your engine more than soda, but there are safer ways to wake up.
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