TIME You Asked

You Asked: What Is Ransomware?

TIME.com stock photos Computer Keyboard Typing Hack
Elizabeth Renstrom for TIME

How to avoid paying hackers to give your computer back

There you are, surfing the web — maybe you’re catching up with Facebook friends, or perhaps you’re reading the news — and seemingly out of nowhere, a window pops up, stopping your computer in its tracks. And there’s only one way to make it go away — pay up.

It’s an absurd scenario, the kind you might find in a movie, right? Tell that to the thousands of people who have been hit with these so-called “ransomware” attacks to date.

“It actually is a phenomenon,” says Candid Wueest, Symantec’s principal threat researcher. Wueest investigates all sorts of bugs that attack computers and mobile devices via the Internet. The first known cases of ransomware date back to 2005, says Wueest, but infections have increased every year since. And last year, ransomware incidents exploded 113% compared to the year before.

“At the moment we’re probably around 30,000 infections per day around the globe,” says Wueest.

There are many different ransomware viruses floating around the web. But in general, they work like Trojan horses, infecting your computer without you knowing. But in this case, the bugs aren’t corrupting your files, they’re locking them down. Ransomware can encrypt everything from your documents to your photos, and without the correct password to unlock them, you may never be able to open these files again. To get that password, you have one option: follow the ransomware’s instructions, which usually involves making a payment to hackers in the amount of — get this — $300.

Technically, the sums vary, but $300 is the average. “We’ve seen some which ask for $500 or even $700, but that seems to be over the top,” says Wueest, who notes that some ransomware even has dynamic pricing depending on the country you’re in. For instance, a virus in the U.S. might ask for $700, but that same bug in India will only require for $500 for the password.

In other words, the key for the hackers behind this scheme is asking for enough money to make the hustle worthwhile, but not so much that the victim can’t afford to pay. And even though the payouts are just hundreds of dollars at a time, quick math shows ransomware is a multi-million dollar industry.

The savviest ransomware not only capitalizes on users’ precious data — like irreplaceable family photos or the only draft of an in-progress novel — but it can also prey on their deepest fears. For example, one virus displays a screen warning users the FBI is on to all those movies they’ve downloaded illegally. And sure enough, lots of people who get that fake warning pay a fine to avoid prosecution. “Many people may have something in their closet that they think maybe was illegal,” says Wueest. “A lot of them started to pay.”

What can you do if you fall victim to ransomware? Sometimes it’s not much, as hackers’ methods are getting more advanced all the time. “The newest versions [of ransomware viruses] have strong, state-of-the-art cryptography which is used all over the Internet, like online banking and e-commerce,” says Wueest. And every victimized computer has its own distinct decryption key — so there’s no secret password that will magically open these locks.

That’s not to say that computers are completely defenseless. According to the FBI, the government is taking proactive steps to shut down these viruses before they reach your computer. And authorities worldwide are working with digital security companies like Symantec to find the digital kidnappers and bring them to justice. But these hackers can be hard to catch because work they in small, anonymous groups located in far-flung countries with largely ineffectual law enforcement.

“We track a few different groups,” says Wueest. “One group made $34,000 in its first month — that’s a pretty good income for a small group.”

But there are ways to protect yourself from these schemes. First, back up your data regularly. Keep your information in a safe place offline, because under the right circumstances ransomware can infect networked storage or even cloud-connected drives. Secondly, use anti-virus software. Ransomware can infect computers in different ways, like launching through email attachments or via malicious code embedded on a website — but anti-virus software is designed to catch these bugs before they take hold. And finally, keep your software and operating system up-to-date. Many viruses exploit weaknesses in older computer programs, which is one reason software developers are constantly issuing patches and bugging you to install them.

Failing these three measures, if you’re infected, you may just have to pay up to free your data. But there’s a catch: Should you actually trust these thieves to provide the decryption key? “We have seen instances where that actually is true and people did get data back, but we don’t recommend it,” says Wueest. That’s because even if you do manage to wring your files from hackers’ grasp, the money you pay them will further fuel their nefarious efforts. And by making you admit defeat, they’ll become emboldened and continue to shake down other Internet users. In other words, the best defense is avoiding ransomware before it takes hold of your computer in the first place.

TIME Mental Health/Psychology

You Asked: Why Do I Blush So Much?

You Asked Why Do I Blush
Illustration by Peter Oumanski for TIME

Blame the company you keep and the color of your skin, among other factors.

Human beings are the only animals that blush. And try as we might, there’s no simple way to suppress it. In fact, trying to hold back a blush is a pretty good way to intensify it, says Dr. Corine Dijk, a clinical psychologist at the University of Amsterdam.

When you feel self-aware or embarrassed, your nervous system sends a signal to muscles in your face instructing them to relax, Dijk says. That relaxing allows small veins in your skin to dilate, which in turn causes blood to pool and your cheeks to redden. (Dijk says blushing shouldn’t be confused with the “flushing” some people experience when angry, which results from a different physiological mechanism.)

If you’re fair skinned, your blush will be more visible than if you had darker skin, says Dr. Peter Drummond, a social scientist and blush researcher at Australia’s Murdoch University. Some hormonal or anatomical quirks—stuff that’s just part of your unique internal architecture and chemistry—could also make you more or less likely to blush, he adds.

But social discomfort really brings on the blushing. Times of embarrassment, guilt or self-consciousness—or some combination of all three—are when your cheeks produce their mortifying rosettes. So if you’re the type who’s quick to feel embarrassed or self-conscious, you’re probably the type who blushes a lot, says Dr. Marije aan het Rot, a behavioral scientist at the University of Groningen in the Netherlands.

Research suggests certain situations are likely to amp up those blush-inducing emotions, aan het Rot says. If you feel inferior to the people around you—either socially or professionally—you may be quick to feel self-conscious (and quick to blush.) People with social phobias often blush at higher rates than those more comfortable in public, aan het Rot adds. Like so many confounding psychological conditions, fearing a thing—in this case, a blush—makes the thing more likely to happen.

Research also suggests being the subject of scrutiny, even if you have no reason to feel ashamed or embarrassed, is enough to launch a rosy reaction. Prolonged eye contact alone can be a blush trigger, Drummond’s experiments have shown.

On the other hand, feeling unconcerned or uninterested in what other people think of you tends to lower the likelihood you’ll blush, Dijk says. While tough to study, it’s possible that by raising your own social or professional status—or by strengthening your disregard for what others think of you—you may blush less often.

However interesting (or discouraging) all of this may be, none of it explains why people turn red when shamed or embarrassed. What utility does your blush serve, and why did we develop the ability to blush in the first place?

There are theories, but not answers. It’s possible that, like a built-in polygraph, your blush is an involuntary admission of wrongdoing. “When you blush, others know that your emotional experience is true and sincere,” Dijk says. That may sound unappealing, but it has its benefits. “When people blush in an embarrassing or shameful situation, they are more likely to be seen by others as likable and trustworthy than if they had not blushed,” aan het Rot says.

In this way, blushing may have developed as a way for humans to better communicate sincere regret or contrition. It’s also possible your blush is just a byproduct of your body’s attempts to cool your brain when blood rushes to your head in embarrassing situations.

What isn’t in doubt is that pretty much everyone views their own blushing as an undesirable habit—though maybe we shouldn’t. Blushers are, in many situations, viewed “favorably,” aan het Rot says.

Keep that in mind, and you may just blush less as a result.

TIME Exercise/Fitness

You Asked: Is It Healthy to Sweat A Lot?

You Asked Healthy Sweat
Illustration by Peter Oumanski for TIME

If you’re hot, perspiration is normal—even lots of it. But there are other times when excessive sweating could be cause for concern.

Here’s the tricky thing about using sweat as a barometer for health: “A lot of it comes down to biological variation,” says Dr. Craig Crandall, a professor of internal medicine at the University of Texas Southwestern Medical Center.

Crandall says if you examined two people—same height, sex and build—one might produce twice the volume of perspiration as the other. “It could just be one person has more sweat glands,” he explains. “Everybody’s baseline is different, so it’s hard to say what amount of sweat is ‘healthy’.”

Still, patterns emerge when you look at big groups of people.

A 2010 study from Japan examined how fit men and women sweat in response to exercise, and compared their sweating rates to those of unfit people. Fit people not only perspire more, but they also start sweating sooner during exercise, says study coauthor Dr. Yoshimitsu Inoue of Osaka International University. Men also tend to sweat more than women, Inoue says.

Crandall says the differences between fit and unfit people has to do with each person’s capacity for heat generation. “A high fitness level allows you to exercise at a higher workload, which generates more heat, which in turn leads to more sweat,” he explains.

He says men tend to sweat more than women for the same reason overweight or obese adults often sweat more than thin people: Their bodies are larger, which leads to greater heat generation during activity.

Crandall’s own research has found people sweat more after spending time in hot climates. “An athlete training here in Texas versus someone up in Montana may sweat differently in the same conditions,” he says. “Their bodies adapt in response to hot or humid environments.”

So sweat is complicated. But most of the research suggests perspiring in response to heat or exercise—whether you sweat a little or a lot—doesn’t mean much about your health.

Of course, there are other forms of sweat that have nothing to do with heat regulation.

People sweat when they’re nervous, and Crandall says nervous sweat tends to come from different glands than exercise- or heat-induced sweat. “The sweat glands that are sensitive to emotions are mostly under the arms, in the palms, and in the soles of the feet,” he says. While that’s unfortunate for nervous sweaters, there’s no evidence that people who sweat a lot due to worry are less healthy than those who aren’t as emotionally sweaty.

There’s also a condition called hyperhidrosis, which is excessive sweating either all over your body or in one particular area, such as your palms or pits. Excessive means up to four or five times what most people would sweat, says Dr. Adam Friedman, a dermatologist and residency program director at the George Washington School of Medicine and Health Sciences.

While the cause of this pernicious perspiration is often not identifiable, it can stem from an infection or illness, certain medications or an underlying endocrine condition like thyroid disease, Friedman says. Because of these links to health concerns, he says people who sweat all the time, day and night, should speak with a doctor.

Regardless of how much you perspire, exactly what you’re perspiring doesn’t vary much from person to person. Crandall says, “Sweat is basically water, sodium chloride, and potassium”—all of which you have to replenish after sweating heavily, he says.

And no, despite what you may have heard from the detox circuit, sweating does not rid your body of “toxins”. “It’s not like parts of the junk food you ate are going to escape through your sweat,” Crandall says. “There’s just no evidence of that.”

TIME Mental Health/Psychology

You Asked: Do I Worry Too Much?

You Asked Do I Worry Too Much
Illustration by Peter Oumanski for TIME

Frequent fretting is unproductive and not so hot for your health.

As human beings, our ability to predict trouble—and outwit it—is one of those cerebral superpowers that set us apart from birds and beasts. But nonstop worrying can be crippling to your life and your immune system.

“Just having a thought about some potential bad thing that might happen—everyone has those,” says Dr. Michelle Newman, director of the Laboratory for Anxiety and Depression Research at Pennsylvania State University. “But if you have difficulty stopping the worry once it starts, that’s one of the ways we define what’s called pathological worry.”

Newman, who is also editor of the journal Behavior Therapy, cites more characteristics of out-of-control worrying, like fixating on things over which you have no control—or which have a low probability of happening—and “catastrophizing” them. Worrying about a loved one who’s driving and picturing the horrible ramifications of an accident is one example; imagining a string of events that might lead to your losing your job and your home is another.

Anxiety is a related feeling that often goes hand in hand with worrying. While it can be a little tricky to separate the two, Newman says the technical difference is that worrying is “verbal-linguistic” while anxiety is “physical.” If you feel tense or on edge while thinking about your job security or your child’s long car trip, you’re experiencing both worry and anxiety. Feel those emotions “more days than not” for a period of six months, and you meet the American Psychiatric Association’s criteria for a diagnosis of generalized anxiety disorder, or GAD. Basically, you’re a chronic worrier.

“I like to say that chronic worry is a process looking for content,” Newman says. “You’ve gotten into the habit of looking for something to be concerned about, and you always find it.”

That’s bad news for several reasons. First and foremost, incessant worrying and anxiety can increase your blood pressure and heart rate and has been linked to an elevated risk for cardiovascular disease. “Anxiety can also over-activate your immune system,” says Dr. Wesley Moons, formerly of the University of California, Davis, and now CEO of his own consulting firm, Moons Analytics.

While at UC Davis, Moons and his graduate student Grant Shields found that people who reacted to stressful situations with anger experienced a smaller immune system response than those who reacted with anxiety. Shields says the sorts of immune system responses his research linked to anxiety could hurt the body’s ability to fight off infection or disease and have been tentatively linked to higher mortality rates.

“That’s not to say getting angry is a healthy reaction to stress,” Moons adds. “But in terms of your immune system, anxiety appears to trigger some different and potentially more detrimental responses.”

But isn’t there a benefit to lots of worrying? After all, if your mind is tackling contingencies and potential threats, you can act now to prevent them—right?

Unfortunately, Newman refutes this idea. “Mostly worrying becomes a process unto itself that doesn’t lead to problem solving or helping you in any way,” she says. If you’re worrying about something, she says, you’re not taking steps to address the source of your worry, if that’s even possible.

When you boil it down, worry is really a failure to live in the moment, Newman says. Activities that attempt to anchor your mind to the present—including yoga and meditation—may help combat incessant worrying. Exercise, massage and other things that alleviate physical tension are also helpful, she says.

Another great way to reign in your worrying is to set aside a specific time and place for it. Select a spot you can get to easily every day, but that isn’t a place where you normally spend time, Newman advises. (A quiet bench in your backyard, maybe, or a chair in your guest room.) Your goal is to give yourself 20 or 30 minutes a day in that space, devoted only to worrying. “The rest of the day, you tell yourself you aren’t going to worry because you will at that time and place,” Newman explains. “The idea is that by isolating your worry, you can control it.”

She says that focusing on a favorite relaxing setting—your “happy place”—also has proven worry-reducing benefits. “Close your eyes,” she says. “Try to vividly picture that place—the sights and smells and sounds you would feel and hear.” Hopefully the place that you see is worry-free.

TIME Exercise/Fitness

You Asked: Is It Better to Sleep In Or Work Out?

Peter Oumanski for TIME

Sleep and exercise are both vital. But if you can’t seem to fit in both, you can sometimes substitute a little of one for a little of the other.

When it comes to your health, there are few absolutes. But that’s not the case with sleep and exercise. You need both, period.

“I couldn’t choose between the two,” says Edward Laskowski, MD, a resident and professor of physical medicine at Mayo Clinic. “Sleep and exercise are like food and water.”

Not only are both necessary, but it’s difficult to get healthy doses of one without the other. “When you look at the research, regular physical activity is important for high-quality sleep, and high-quality sleep is important for physical performance,” says Cheri Mah, a sleep medicine researcher at Stanford University and the University of California, San Francisco.

But when pressed to choose one that’s more important, Mah grudgingly decides on sleep. “Sleep is foundational,” she says. While specific needs vary from person to person, she says most of the scientific literature suggests adults need a minimum of seven hours of good sleep every night. “Lots of individuals think they can operate on less, but when you test them, you find they’re not performing at their best,” Mah says. “They get used to feeling tired, and they think that’s the norm.”

Sleep is the base on which a healthy mind and body stand, she explains. From your immune function to your mood, energy, appetite and dozens of other health variables, if that base is wobbly, your health will suffer.

But let’s assume you’re getting your seven-plus hours every night. Can you sacrifice some zzzs a few times a week in order to fit in regular exercise? Yes, but with caveats, says Dr. Phyllis Zee, director of the Center for Circadian and Sleep Medicine at Northwestern University.

Regularity is very important for sound, restorative sleep. Mess around too much with your sleep and wake schedule, and all of your body’s circadian rhythms can be thrown out of whack. Not only will you feel sleepy at odd hours, but you may also struggle to fall asleep at night, and your appetite and energy will fluctuate in unhealthy ways, Zee says.

Say you typically go to bed around 11:00 p.m. and rise at seven. Zee says the midpoint of your night would land near 3 a.m. As long as you’re maintaining your seven-to-eight-hour average and that midpoint lands between 2 a.m. and 4 a.m., Zee says you’re fine skipping a half hour of sleep a few days a week in favor of a morning run or gym visit.

Not fine: Rising two hours early to attend a morning yoga class or to fit in a lengthy bike ride.

“Even on weekends, you want to keep that regularity of when you go to bed and when you get up,” Zee stresses. Your body doesn’t understand what a weekend is, so it doesn’t react well if you stick to one schedule during the workweek and adopt a radically different schedule on Saturdays and Sundays. The same goes for your workout days.

But if you’re falling short of your seven hours a night, Zee, Mah and Laskowski all say the same thing: It’s time to reorganize your schedule in a way that makes room for both adequate sleep and regular exercise.

There may be some exceptions for people with insomnia or those who can’t seem to sleep at night. For them, rising at the same time each day and incorporating regular exercise might help alleviate sleep woes, even if it means sacrificing a little sack time in the short term.

But for the rest of us, making time for sleep and exercise can come down to cutting out activities that aren’t as important.

“Almost everyone could forgo 30 minutes a day of internet or TV time,” Mah says. Both the CDC and American Heart Association recommend a minimum of 2.5 hours of moderate-intensity aerobic exercise every week. Along with your seven-plus hours of sleep, those are you bare-minimum goals when it comes to healthy rest and physical activity.

“There are so many unique benefits that each have, it’s hard to pull them apart,” Laskowski says. “The real danger is when you only make adequate time for one of them.”

TIME Diet/Nutrition

You Asked: Can I Scrape Mold Off of Food and Eat It?

Can I eat moldy food
Illustration by Peter Oumanski for TIME

Believe it or not, you can eat food with fuzz. But only when it comes to certain stuff.

Nobody wants to waste food. So when you see something hairy in your cream cheese or suspicious spots on your bread, it’s tempting to scrape the mold away and chow down. But in most cases—including the two just mentioned—munching moldy food is a bad idea, says Kristin Kirkpatrick, a registered dietitian and wellness manager at Cleveland Clinic.

Kirkpatrick says that when visible mold is present, its tentacles—called “threads”—have likely penetrated deep into your food, contaminating even those parts that appear to be mold-free.

The health risks of mold exposure are many. “Mold can produce toxic substances, called mycotoxins,” says Katie George, a clinical dietitian at the University of Kansas Hospital. These toxins can cause respiratory problems, allergic reactions and illness. George says aflatoxin, a specific type mycotoxin found in nuts and grains, can even be cancer-causing.

Mold is usually easy to spot. It often appears as a blue or green discoloration, which can grow a hairy coat if left long enough, Kirkpatrick says. If you’re examining foods in jars—things like pasta sauce or salsa—it’s best to check the underside of the lid and rim of the container for suspicious growths.

Just don’t sniff your foods, Kirkpatrick warns, which could lead to you inhaling mold spores. If you’re worried about mold but don’t see any growths, use common sense. “If the food doesn’t look the way it normally would, and especially if it seems moisture-soaked, toss it,” Kirkpatrick says.

The exceptions: Hard block cheeses like parmesan, cheddar or Swiss. “With those, the mold generally won’t penetrate deep into the product,” Kirkpatrick says. But don’t start scraping, which can release mold spores into the air or allow them to spread to your countertops or other foods. The only safe way to remove that mold is to cut away an inch of cheese all the way around the spot, she says. “You’ll probably cut away some safe parts, but that’s a good rule of thumb.”

A similar rule applies to some super-dense meats, like hard salami or cured ham. If mold is present, Kirkpatrick says you can cut it away and still enjoy these meats. But again, avoid scraping.

She also advises tossing the moldy bits in your trash—not your sink, where they could release spores or be splashed onto nearby countertops or dishes. Be sure not to use the same knife to prepare food that you used to remove the mold, too.

If you want to cut down the risk of mold in the first place, make sure you keep the inside of your fridge clean, George says. If bits of food or spilled condiments sit for weeks or months, the mold they harbor could spread to other foods—even fresh stuff. She also recommends keeping every food covered in your refrigerator to avoid cross-contamination.

Also, toss any prepared foods—things like casseroles or dinner leftovers—after two days. “Forty-eight hours is probably pretty conservative,” Kirkpatrick says. “But why take the chance?” Playing it safe is especially important for people with weakened immune systems, she says.

Her final piece of advice is probably your best course of action when it comes to moldy food: “When in doubt,” she says, “throw it out.”

TIME Pain

You Asked: Do High Heels Actually Damage My Feet?

You Asked: Do High Heels Actually Damage My Feet?
Illustration by Peter Oumanski for TIME

Yep. And the damage doesn’t end at your toes.

High heels hurt. If you’ve worn them (I have not) then you probably know this already. But are high heels also bad for you? A 2014 survey from the American Podiatric Medical Association—composed of the nation’s top foot and lower-leg docs—found heels were far and away the most common cause of foot pain among women.

Unsurprisingly, much of that pain comes from contorting your foot into a steep “plantarflexed” position, concludes a study from the Journal of Applied Physiology. Like standing on your tiptoes for hours, that high-heeled posture may lead to painful muscle fatigue and strain injuries, the authors of that study say.

Calluses, blisters, bunions, and ingrown nails are all common among high heel wearers, adds Dr. Rodney Stuck, division director of podiatry at Loyola University Chicago. The higher the heel, the more trouble you’re likely to run (or walk) into, Stuck says.

But the most significant risks of your high-heel habit may begin higher up your leg. According to research from the U.K. and Austria, lots of time spent walking in heels actually changes the structure of the muscles and tendons in your calves—and not for the better.

High heels lead to shorter muscle fibers and a toughening of the Achilles tendon, says Dr. Marco Narici, a professor of clinical physiology at the University of Nottingham (and coauthor of that study). Narici says these muscle changes reduce your ankle’s range of motion, and contribute to your risk for strains and sprains. Stuck says these sorts of muscle adaptations may also up your risk for other lower-body injuries. A sore ankle or leg you blamed on running may actually have more to do with your high heels, he says.

More research shows walking in heels puts a great deal of force on your kneecaps. This force can lead to the early onset of osteoarthritis, says Dr. Constance Chu, a professor of orthopedic surgery at Stanford.

Chu says this risk increases among heavier women. “Combining walking in very high heels for long periods of time every day with obesity and aging would be a perfect storm for knee osteoarthritis, as well as foot, back, and other joint problems,” she says.

Of course, tossing your stilettos is the one surefire way to dodge all these potential health hazards. But if you’re not willing to part with your pumps, Chu says lower heels lowers your risk. For formal or work events when you feel heels are a must, she recommends wearing flats beforehand and changing into your heels only when you’ve arrived at your destination. “Taking time to sit and move the knees through a full range of motion may also be helpful,” she says.

Loyola University’s Stuck also suggests standing against a wall or with one foot on a step and stretching your feet for a few minutes every day.

But don’t swap your heels for flip-flops. An Auburn University study found the way those loose summer sandals shorten your gait and force you to grip with your toes may lead to all sorts of heel, ankle, and sole problems.

Feet sure don’t have it easy.

Read next: These High-Tech High Heels Change Color With the Click of an App

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TIME Diet/Nutrition

You Asked: Your Top 10 Health Questions Answered

TIME answers your burning questions on health and wellness. Click the caption for the full answer

TIME Exercise/Fitness

You Asked: Should I Do The Insanity Workout?

Illustration by Peter Oumanski for TIME

Expect results—though maybe not the ones you’d hoped for.

The name alone is a challenge—a dare. You’d have to be insane to attempt this workout. Of course, that’s a big part of the appeal. If the exercise is “extreme” or “crazy,” you assume the body benefits will be dramatic. And they may be—just not in the ways you’d expect from checking out the workout’s promotional materials, which emphasize weight loss.

While it’s continually changing, the latest iteration of “INSANITY” is a 60-day program composed of 30-minute bouts of very high-intensity aerobic and resistance exercise, to be completed six days a week. While research has linked physical fitness gains to Insanity-style interval workouts, the evidence that these programs lead to weight loss is anything but rock solid.

“We’ve shown that when it comes to cardiovascular fitness and function, greater intensity leads to greater adaptations,” says Todd Astorino, PhD, associate professor in the department of kinesiology at California State University, San Marcos.

Astorino has studied the health and fitness effects of very rigorous bouts of interval training, often referred to as high-intensity interval training (HIIT). He says there’s little doubt your athletic condition—the ability of your heart and lungs to handle physical activity—would improve if you completed something along the lines of an Insanity workout. He also says your blood sugar levels would likely drop, a change that could help protect you from metabolic diseases like type-2 diabetes. Throw in the body-resistance component of Insanity workouts, and you’ll certainly grow stronger too.

What about weight loss? “The research is very mixed, especially in the long term,” Astorino says. “I think it would help you avoid weight gain. But that’s not the same as losing weight.”

Hundreds of studies have looked into the effect of regular exercise on body weight. While physical activity is unquestionably good for your health, exercise alone doesn’t have a huge impact on the number you see on your bathroom scale, concludes one recent study appearing in the journal Obesity Reviews.

MORE You Asked: Why Are People Addicted To CrossFit?

Another study, this one from Stephen Boutcher, PhD, associate professor at Australia’s University of New South Wales, specifically examined the effect of Insanity-style HIIT training on body fat. Boutcher’s research found “significant” fat reduction—or a little more than 4 pounds of lost body fat after three months of training. That’s significant in science terms, but probably not what you’re expecting when starting a workout program that highlights happy customers who have lost 40, 50, or even 90 pounds.

Boutcher says there’s some evidence HIIT training may help suppress appetite in ways traditional aerobic exercise doesn’t. But to shed lots of weight—the kind of “total-body” transformation you see in product testimonials—you also have to eat a healthy diet, the research suggests. (Read the fine print on the INSANITY website, and you’ll find analogous disclaimers stating a “proper diet” is necessary to achieve and maintain weight loss.)

But for some people, even regular exercise and an improved diet won’t dramatically change the way their bodies look. “Many people are just naturally bigger,” Astorino says. “For them, trying to look physically lean would probably require some very dramatic diet restrictions.”

Of course, none of this touches on the psychological perks of challenging yourself with a butt-whipping exercise regimen. Talk to someone who has run a marathon or finished an Insanity program, and you can hear the sense of accomplishment and pride they feel when they talk about their achievement.

“If you can get through something like this, you’ll have confidence and a good understanding of what your body can tolerate,” Astorino says. Those benefits, along with improved endurance and metabolic health, are nothing to scoff at. But if you’re expecting to transform your body and drop several sizes with INSANITY, the results might not be as crazy as you’d hoped.

Read next: A Workout You Can Do Anywhere

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TIME You Asked

You Asked: What Can I Do When My iPhone’s Battery Is Dying?

iPhone 6 Becomes Available In Hong Kong
Lam Yik Fei—Getty Images Customer looks at the new iPhones on display at the launch of the new Apple iPhone 6 and iPhone 6 Plus at the Apple IFC store on September 19, 2014 in Hong Kong, China.

iPhone battery dipping dangerously low? Here's what to do

There are few things as stressful as the moment you realize your iPhone is dipping below the 20% battery life mark. It’s a feeling of terror and uncertainty — especially if you’re far from an outlet.

But fear not. Here’s what to do to get every last drop of battery life from your soon-to-be-deceased iPhone.

First, close all those apps running in the background. To do this, double-tap your home button and then swipe up to close apps.

Next, go to Settings -> Cellular and switch “Cellular Data” to the off position. This will cut your iPhone off from wireless Internet service, meaning you’ll be without access to email or iMessage — but you’ll still be able to make calls and send and receive regular SMS texts.

If you really don’t need to be accessible for a while and you’re just trying to save your iPhone for when you’ll need it later, swipe up from the bottom of your screen and hit the airplane icon on the far left to turn on Airplane Mode, which will disable all communications while cutting down dramatically on battery usage (You should also do this when you’re out of cell range for a while, say, in a subway tunnel).

Finally, lower your screen brightness by swiping up from the bottom of your phone and moving the brightness slider to the left. That’ll make your iPhone harder to read, but powering a bright screen eats up a whole lot of your iPhone’s battery power.

But these are all emergency protocols to be followed in the most desperate of times. There are other steps you can take to keep your battery healthy so it won’t ever come to this.

For instance: Always let your battery drain as close to 0% as possible before charging it, then charge it all the way back to 100%. That’ll help maintain your battery’s integrity.

Another backup option? Keep an external battery pack or charging case like a Tenergy or Mophie handy. Some of Tenergy’s battery packs have two cables, so you can help a friend or a date in need, too. Nova also makes a popular small battery pack.

It’s worth noting here that some of Amazon’s highest-rated battery packs are well-reviewed just because they’re inexpensive, not because they’re small or high-capacity — so make sure you’re getting what you want before you click “Buy.”

Read next: How to Make Your Android Battery Last Longer

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