How Sleeping Can Help You Build Muscle
It's fine to binge just one more episode of Queer Eye, right? Turns out, your strength gains might be much better if you say, "sayonara!" to Antoni (as much as we adore his avocado hacks) and squeeze in a little extra shut-eye. Here's the science.
Why You Need Sleep to Build Muscle
To build muscle, you need to get serious about sleep, says Shape Brain Trust member Michele Olson, Ph.D., a professor of sport science at Huntingdon College in Alabama. When you work out, you break down your muscles. But after you drift off, your body regenerates them. That’s when you *really* get stronger. (More here: The Science of Building Muscle and Burning Fat)
As you sleep, the pituitary gland releases growth hormone, which in turn stimulates your body to produce insulin-like growth factor—hormones essential for muscle repair, Olson says. While your body doubles down on turning protein from your diet into amino acids, the insulin-like growth factor “pushes carbs into your muscle cells, giving them energy to use those amino acids to create new cells and repair broken-down tissue,” Olson says.
This rebuilding process enables you to run faster and longer, lift heavier, jump higher, and look and feel great. In addition to what you do in the gym, you can also support your body’s nighttime repair work, research shows. (Related: Why Sleep Is the No. 1 Most Important Thing For a Better Body)
Here are five tricks to maximize the process to boost your strength, endurance, and reaction time.
1. Sleep Longer ...
Your muscles can’t grow stronger if you’re not getting enough sleep. Aim to be in bed for eight hours each night, Olson says. If you’re working out intensely— training for a marathon, for instance—you may need an hour more for proper muscle repair and recovery, says John Underwood, the director of the Human Performance Project.
In fact, less than eight hours can actually shrink your muscles, research shows. Not enough z’s keeps your levels of cortisol, a stress hormone, high at night, “which inhibits the repair of muscle tissue,” Olson says. (Related: This Is the Actual Definition of a "Good Night's Sleep")
2. ... And More Deeply.
The quality of your z’s is as important for your muscles as the duration. So practice good sleep hygiene, Underwood says: Turn off electronics 30 to 60 minutes before bed; keep your bedroom cool, dark, and quiet; and go to bed around the same time every night. (And if you need a zen moment before turning in, try these 10 yoga poses.)
“The biggest growth hormone spike occurs 70 to 120 minutes after you fall asleep,” Underwood says. An erratic sleep schedule throws this off, though. Research shows that if you usually turn in around 10 p.m., going to bed at midnight once will reduce your growth hormone level significantly, even if you still sleep for eight hours, Underwood says. A late night or two every so often won’t be enough to thwart your gains, but to maximize your muscle health, try to make bedtime as regular as possible. (Related: Is It Better to Sleep In or Work Out?)
3. Skip the Extra Drink.
“Having one or two cocktails can lower growth hormone levels slightly. But if you drink enough to get intoxicated, they plummet by 70 percent and new muscle-mass formation drops by 63 percent,” Underwood says. Alcohol reduces sleep quality, which may be why it interferes with growth hormone production. It also boosts inflammation, which can make you more sore the following day. (So that's why we often wake up early—and often with a headache—after a night of drinking.)
A glass of wine with dinner a few times a week is probably fine. But leave plenty of time between your last drink and lights out. Same goes for dessert. “Food containing processed sugar will increase cortisol, often to levels that can disrupt sleep,” Olson says. If you hit a fitness plateau and aren’t quite sure why, try cutting back on booze and sweets.
4. Eat Protein Before Bed.
“Muscles are made up of amino acids, which come from protein in your diet,” says Tim Snijders, Ph.D., an assistant professor at Maastricht University in the Netherlands, who has studied the effects of protein before bed. “If you don’t have enough in your body overnight, your system could break down more muscle than it builds.”
If you eat 30 grams of protein half an hour before you go to sleep, your body will have adequate amino acids for your muscles to use for their repair work. Stick to casein protein, found in milk, yogurt, and cottage cheese. “It’s a slow-digesting type, so it will sustain you all night,” Snijders says. (Related: The Best Late-Night Snacks)
While you certainly can eat your way towards better sleep all day long, you may not need this extra hit of protein if you get enough during your other meals and snacks. Active women should try to get 0.5 to 0.7 grams per pound of body weight a day; for a 140-pound woman, that comes to 70 to 98 grams daily.
5. Finally, Be Consistent with Weight Training.
Of course, sometimes getting eight hours just doesn’t happen. Luckily, there’s evidence that strength training can reduce or even halt the muscle-shrinking effects of not enough sleep.
In an article in the journal Medical Hypothesis, researchers reported that resistance exercise boosts levels of testosterone, growth hormone, and insulin-like growth factor, which may help protect the muscles from atrophy. And animal research shows that rats who did resistance training before being deprived of sleep lost much less muscle than those that didn’t, according to the journal Applied Physiology, Nutrition, and Metabolism.
Even though you may struggle to build muscle without enough rest, sticking to a regular weight lifting routine can keep you from losing what you have. (Related: Strength HIIT Workout Videos That'll Push You to the Limit)
Shape Magazine, November 2019 issue