Why tiredness makes you skinny and healthy

When you’re exhausted, going to the gym is probably the last thing you want to do, but it turns out that’s when you should go.

According to a new study to be published in the Journal of Consumer Research, people make better health decisions when they’re feeling tired and rundown.

The urge to take care of our bodies when we're sleepy could be biological. “We proposed that people are more motivated to engage in healthful behavior when they are depleted and perceive their safety to be at stake," wrote study authors Monika Lisjak, assistant professor of marketing at Erasmus University in the Netherlands and Angela Y. Lee, professor of marketing at Northwestern University.

In the study, researchers asked subjects to read about the dangers of kidney disease and early detection, those with a family history included. Afterwards, those who were feeling exhausted expressed a higher likelihood of being tested than their energized counterparts.

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In another study, subjects were asked to complete a survey on health and fitness, either before or after hitting the gym. After the survey, everyone was told to choose between a gift of sunblock or moisturizer. Those who had worked out were more likely to select the skin-saving sunblock.

The results are surprising, given past research about how exhaustion affects the brain. According to Harvard University, sleep-deprivation affects our moods, appetites, and ability to focus. And any gym-goer can attest to that feeling of denial when their alarm goes off in the morning.

But making wise health decisions is doable, even when you’re not feeling it, according to Will Torres, personal trainer and owner of Willspace, a gym in New York City. “If you’re truly exhausted, it’s best to just go to sleep, but if you just need to recharge, there are simple things you can do,” he tells Yahoo Shine.

Get your heart rate up:

Let’s say you’re exhausted because you’ve been slouched over your desk all morning. Simply straightening up will boost your energy levels. “When you’re slumping, you can’t take a full breath because bad posture compresses the diaphragm,” says Torres. “Sitting up straight allows your lungs to take in more air, which sends a message to your brain to wake up.” Or (if you have forgiving officemates), try 20 jumping jacks and 10 squats. “It’s not a work out, per se, but you will feel more awake,” he says.

Eat more fibre:

“People tend to reach for sugary foods to give them a quick boost of energy, but without fibre to slow digestion down, they’ll crash,” says Torres. Rather than an energy bar or mixed-fruit smoothie (both of which are loaded with sugar), try a fibre-filled apple, piece of watermelon, or pear.

Stay away from new routines:

You’ve been wanting to try kickboxing for ages, but when you're tired not the time. “Starting a new type of workout takes coordination and focus and tired people have neither,” says Torres. “When you’re exhausted, do things you’ve always done or try running, weight machines, or brisk walking to avoid injury.”

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