You're so predictable. Every day, you run out of steam, lose juice, or otherwise hit the wall at nearly the exact same times.
How do we know? Because it happens to everyone. Okay, maybe not to Kelly Ripa, but to everyone else. In fact, it's like clockwork, which actually makes sense, because your body clock is part of the problem -- when your internal chronometer is out of whack, you feel wiped out. There are other reasons, too. We detail all of them on these pages, and provide a quick fix -- or at least a work-around -- for each power suck. Consider your energy crisis solved.
7 a.m.: The Morning Fog
You would think that if there were one time you'd feel naturally alert and energized, it would be after 8 hours of resting and recharging. Instead, your mind is mush. Why? Blame a phenomenon called "sleep inertia." When you first awaken, the parts of your brain associated with consciousness -- the thalamus and brain stem -- begin firing right away. But the prefrontal cortex, which handles problem solving and complex thought, is like a cold engine -- it needs time to warm up.
"Sleep inertia can last for up to 2 hours, although it's most severe within the first 10 minutes of waking," says Kenneth Wright, Ph.D., an assistant professor of integrative physiology at the University of Colorado. Wright and his colleagues discovered just how severe in a new study, which shows that the mental impairment caused by sleep inertia is akin to being intoxicated. Adding to your addled state is the fact that you also have a nearly empty fuel tank. "Your brain needs a continuous supply of glucose to function optimally," says Caroline Mahoney, Ph.D., a research psychologist at the U.S. Army Soldier Center.
Fill it up. Make your morning meal a bowl of instant oatmeal prepared with skim milk. Tufts University researchers recently found that people who ate one packet of instant oatmeal spiked with 1/2 cup of skim milk received a steady glucose infusion, which increased their alertness all morning and improved their ability to process information. And if you aren't already jolting yourself with java, start; a University of Pennsylvania study shows that a dose of caffeine can combat sleep inertia.
Just don't let a latte replace a real meal. "It will mask your low blood sugar by temporarily stimulating your brain," says Dan Benardot, Ph.D., R.D., an associate professor of nutrition at Georgia State University. "But you won't have done anything to satisfy the need for energy."
1 p.m.: The Lunchtime Letdown
If your typical lunch consists of carbs a la starch, then you've experienced this early-afternoon brain drain. That's because a high-carbohydrate meal is the surest way to cause your insulin levels to spike -- and your concentration to crash.
"A high insulin response will rapidly take too much sugar out of your blood," says Benardot. "Then your brain doesn't have enough of its primary fuel, so you become mentally fatigued."
Order a combo meal. If you can't (or won't) limit your lunchtime carbohydrate consumption, work in extra fiber to slow your digestion and the release of insulin, says Susan Kleiner, Ph.D., R.D., owner of the consulting firm High Performance Nutrition. For example, if your noon nosh includes a baked potato, make sure you eat the skin, which is dense with a type of fiber called pectin. "Pectin slows everything down in the gastrointestinal tract," says Kleiner.
"When food passes more slowly through the intestines, absorption into the bloodstream proceeds in a more timed-release fashion." (More ways to fortify your lunch with fiber.) In those instances when you give in to a binge, snack on grapes or an apple afterward; either fruit will help stabilize your blood sugar, says Benardot.
3 p.m.: The Afternoon Slump
Deep down inside, you're a conflicted man. In one corner, there's your body clock, a.k.a. your circadian clock, which fights to keep you awake until bedtime. In the other corner, there's your homeostatic system, which competes to make you sleepy. And every day, between approximately 2 p.m. and 4 p.m., the homeostatic system tries to score a knockout. "We think the afternoon dip in alertness occurs because the drive from the circadian clock to stay awake is not yet strong enough to cancel out the sleep drive caused by having been awake for half the day," says Wright.
Expose yourself. As in, give yourself a shot of sunlight. The sun's rays will provide a boost to your circadian clock that should solve your afternoon slump -- if you time things right. "The key is adequate exposure to sunlight very quickly after you wake up in the morning," says Michael Terman, Ph.D., a professor of clinical psychology at Columbia University medical center. "As you move into the middle of the day, the same amount of light exposure doesn't affect the circadian clock at all."
That said, take it outside in the afternoon anyway: British researchers recently found that when people exercised during their workday -- regardless of the duration or intensity of the movement -- they were less likely to feel fatigued, and that translated into a 15 percent improvement in job performance.
6 p.m.: The Preworkout Conk-Out
It's the catch-22 of exercising in the early evening: You know that working out will leave you energized, but you don't have the energy to work out. In most cases, the problem is simply that you've forgotten a critical piece of exercise equipment: food. "If you're going into a workout when you haven't eaten since lunch, your blood sugar will be low again," says Kleiner.
Snack before you sweat. Schedule a small snack roughly an hour and a half before your postwork workout. The ideal mini meal totals 250 calories and consists of 25 to 35 grams (g) carbohydrates, 10 to 15 g protein, and up to 5 g fat, says Kleiner. Two handfuls of pretzels and two slices of cheese fits the nutritional bill, as does a Myoplex Lite bar.
Then, before you hit the locker room, grab the original energy drink: Gatorade. "It hasn't really been improved upon," says Laura Dunne, M.D., of the Sports Medicine Institute at Orthopaedic Associates of Allentown, in Pennsylvania. "The simple sugars will cause a fast spike in your blood-sugar level, so you'll have immediate energy." At the same time, you'll be addressing dehydration, another hidden cause of fatigue. "Often, that sluggish feeling has more to do with not having had enough fluid than with anything else," says Dr. Dunne.
8 p.m.: The Prime-Time Torpor
There's no complicated biochemical reason for being tired now -- you worked all day! But it's early, and even if you don't have plans, falling asleep now will only screw up your body clock and leave you feeling more fatigued in the a.m. "Going to bed a couple of hours earlier than you normally do will throw off your rhythms, while consistency can really help you feel alert during the day," says Philip Gehrman, Ph.D., an assistant professor of psychology at the University of the Sciences, in Philadelphia.
Rock yourself awake. First, do not stretch out on the couch or recline in your easy chair. "Underlying sleepiness becomes more apparent when we put ourselves in sleep-conducive positions, such as lying down," says Wright. And instead of turning on the TV, power up your iPod. "To increase the perception of energy, listen to a piece of music that is upbeat and familiar, and use that song to get you going," says Andrea Scheve, director of the University of Pittsburgh medical center music-therapy program.
"Even just thinking about it and hearing it in your mind can give you a boost of energy." What you do with this newfound energy is up to you, but if you have a significant other, now actually might be the perfect time to head for bed.
Shut It Off
It would be funny if it weren't so frustrating: You spend the entire day fighting fatigue, only to slip into bed, shut your eyes, and suddenly realize that you now have too much energy.
Fortunately, there's an explanation, and it's pure Pavlov. Do you do anything in bed besides sleep? Maybe read, watch TV, or play Sudoku? "These activities train the brain to associate the bed with excitement," says Kenneth Wright, Ph.D., an assistant professor of integrative physiology at the University of Colorado. "Some people become so sensitive to this that when they go to bed, all of a sudden their brain's aroused, because normally they're watching a basketball game or reading a favorite book."
Which means the fix is what sleep researchers have recommended all along: no books, no Leno, and definitely no laptop when you're under the covers. Sex is fine -- it is, after all, nature's perfect sleep aid.
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