As vantagens dos impactos nos seus ossos

    Os Jovens e os adultos saudáveis devem de vez em quando fazer uns sprints, saltar para cima de uma degrau, saltar de um degrau para o chão ou saltitar no mesmo sitio.
    Estudos realizados em mulheres que saltaram para um step e voltaram a saltar para o chão: Repetiram 1o saltos, com intervalos de 30 segundos, pelo menos duas vezes por dia, ao fim de uns meses a sua densidade óssea aumentou consideravelmente. E  noutro grupo que fizeram 20 repetições o aumento ainda foi maior.

Bones should be jarred, for their own good. Past experiments have definitively established that subjecting bones to abrupt stress prompts them to add mass or at least reduces their loss of mass as people age. What has been in dispute, however, is how much force is needed to stimulate bone — and how to apply that force in daily life.

Recently researchers at the University of Bristolgathered male and female adolescents — the body accumulates bone mass rapidly at this time of life — and had them go about their daily routines while they wore activity monitors. The bone density of the volunteers’ hips was also measured.
A week later, the scientists reclaimed the monitors to check each teenager’s exposure to G forces­, a measure of impact. Those who experienced impacts of 4.2 G’s or greater — though these were infrequent — had notably sturdier hipbones. Additional work done by the same researchers showed that running a 10-minute mile or jumping up onto and down from a box at least 15 inches high was needed to produce forces that great. The significance of these findings is that people should probably run pretty fast or jump high to generate forces great enough to help build bone.

Unfortunately, few older adults are likely to be doing so. In follow-up experiments, the same researchers equipped 20 women older than 60 with activity monitors and ran them through an aerobics class, several brief and increasingly brisk walks and a session of stepping onto and off a foot-high box. None of the women reached the 4-G threshold ­— none, in fact, generated more than 2.1 G’s of force at any point during the various exercises.
The implications are somewhat concerning. Dr. Jon Tobias, a professor of rheumatology at the University of Bristol who led the experiments, says that while impacts that produce fewer than 4 G’s of force may help adults maintain bone mass — a possibility that he and his colleagues are exploring in ongoing experiments — it’s unclear what level of force below 4 G’s is needed.
So, Dr. Tobias says, young people and healthy adults should probably pound the ground, at least sometimes. Sprint. Jump off a box 15 inches or higher at your gym and jump back up. Hop in place. A study by other researchers published in January found that women between 25 and 50 who hopped at least 10 times twice a day, with 30 seconds between each hop, significantly increased their hipbone density after four months. Another group of subjects, who hopped 20 times daily, showed even greater gains.

Alas, a kind of Catch-22 confronts older individuals who have not been engaging in high-impact exercise: Their bodies and bones may not be capable of handling the types of activity most likely to improve bone health. Dr. Tobias and his colleagues hope to better understand what level of impact will benefit these people. In the meantime, anyone uncertain about the state of his or her bones should consult a physician before undertaking high-impact exercise (a caveat that also applies to those with a history of joint problems, including arthritis). For his part, Dr. Tobias says, “I plan to keep running until my joints wear out.”

Fonte: LifeHack

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Threats to Your Kids’ Privacy, and What You Can Do About Them

Remember back in school, when your teachers warned that everything you did would go on your permanent record? It turns out your teachers have become right. That permanent record is the Internet.

It’s hard to be a fully functioning adult in 2014 and not leave behind a digital trail. Now imagine how hard it is for your kids, who have never known a world where the net did not exist.

From the moment they emerge from the womb, they’re generating data, which is then eagerly absorbed and stored by Internet companies, government agencies and some evil no-goodniks.

Despite federal laws prohibiting the collection of data from children under the age of 13, dossiers are constantly being created about your kids, whether it’s Google capturing their search histories, advertisers creating profiles of their interests, or their grandparents tagging photos of them on Facebook. Some of this information is anonymous; some isn’t. And nearly all of this data collection is invisible to you and me.

Sure, you could try to keep them off the net, refuse to buy them cell phones, go Full Amish if you have to. Even in the unlikely event that you manage to pull that off, you’ll do more harm than good. Despite its many flaws, the Internet is still the greatest repository of knowledge on the planet. But there are things you can do to minimize the exposure.

I had a lovely chat about this topic with Julia Angwin, award-winning journalist and author of the brand-new book Dragnet Nation. Angwin is something of a privacy ninja, and she’s raising her two kids — a 9-year-old girl and her 6-year-old brother — to be mini-ninjas themselves.

Angwin says that when it comes to data collection, kids have pretty much the same problems you and I have: They are big, fat targets for data-hungry websites, identity thieves and worse. But you can thwart most of these threats with a few simple tricks.

Privacy problem #1: Insatiable data hounds
Every website you visit, including the one you’re now reading, collects data about you. Data brokers then hoover up information from multiple sites to create a detailed profile — from how much money you make to your travel habits, sexual preferences, religious beliefs, even whom you’re likely to vote for.

Angwin doesn’t want data brokers creating dossiers on her kids before they’ve had a chance to define who they are.

“I want them to learn how to participate in the digital world, but I don’t feel there’s any reason to create a permanent historical record tied to their identities,” she says.

The fix: Separate their real-world identities from their online ones. In other words, urge your kids to use fake names when registering online, and then change those names periodically. Angwin admits to some misgivings about teaching her kids to essentially lie. She says it’s not the best solution for everyone. But it’s still better than the alternative, which is allowing data brokers to run wild with her kids’ data.

Privacy problem #2: Nosy ad networks
Profiles can also be created via “tracking cookies” left behind by advertising networks. These small files are dropped on your computer when you visit websites. They help the networks anonymously record which sites you visit and then display ads based on products they think you’d be interested in. But nobody can guarantee that this data will remain anonymous, nor can we predict how it will be used in the future. You might be shown higher prices for a Disney cruise based on your profile. You or your child could theoretically be denied a job or a loan.

The fix: Angwin uses Ghostery, a free browser plug-in that removes tracking cookies from your computer. She says her daughter became entranced by Ghostery’s animated mascot, a cute blue ghost. It became a game for her to watch it eat the tracking cookies one by one. On the family iPad, Angwin uses Disconnect Kids to achieve the same result.

Privacy problem #3: Evil identity thieves
Kids are a particularly juicy target for identity theft. Steal a child’s Social Security number, and you can obtain credit cards in her name and get away with it for years before anyone finds out. The most common way attackers steal this kind of information is to guess the passwords for online accounts or fool people into giving them up, usually via phishing emails.

The fix: Don’t be fooled by phisher emails, and use stronger passwords. Angwin has taught her daughter the Diceware method to generate passwords, which involves rolling five dice. Each five-digit number you produce corresponds to one of 7,776 short English words on the Diceware list. Roll the dice five times, and you end up with a passphrase (like “acorn brisk chad deep elk”) that’s nearly impossible to guess.

Her daughter has gotten so good at it that she’s started a business where she generates complex passwords and sells them to family friends for a buck apiece, Angwin says.

Privacy problem #4: Photos never die
Put a picture online, and you lose all control over what happens to it. The wrong photo can ruin your child’s reputation, get him in trouble at school, cause him to be bullied or keep him from being accepted into the college of his choice.

The fix: Angwin does not put pictures of her kids online, anywhere. She’s hoping they will do the same when they get to the selfie stage (her daughter is just about there). And while she can’t keep her kids’ school from posting pictures from field trips, or doting relatives from sharing them on Facebook, she does try to make sure that the images are neither captioned nor tagged with her kids’ names, making it much harder to identify them.

Privacy problem #5: Webcam spies are watching
The idea that a stranger could secretly spy on your child via webcam sounds like the plot of a bad movie. That’s probably what Cassidy Wolf thought until a classmate hacked into her webcam, captured images of the 19-year-old Miss Teen USA in the buff, and attempted to blackmail her with them. Malware that allows cyber creeps to remotely operate webcams has become increasingly common.

The fix: This is one of the rare problems where the solution is quite literally a Band-Aid. Angwin has her kids put stickers over the cams on the laptop they share, which they remove when they want to capture videos. If only all privacy problems were this easy to fix.

Big MotherOf course, Angwin’s kids are still relatively young. The real fun begins in a few years when they decide to join Tumblr, engage in Snapchats, and get up to even scarier shenanigans. At that point, one of the biggest threats to kids’ privacy is often their own parents.

Angwin has vowed to not use technology to keep an eye on her own kids, though she acknowledges that could change.

“My parents never knew what I was doing most of the time, and honestly we were all better off for it,” she says. “But if I do succumb to surveilling my kids, I plan to be very open about it. I think if they know someone is watching, they’ll do things that are more socially appropriate.”

Call me when they’re teenagers, Julia, and we’ll talk.

How to Clean Your Smelly Workout Clothes Properly

Before you head out to replace those stinky duds, consider the following tips and tricks for cleaning even the worst smelling bike shorts and sports bras:   Hang Dry Immediately If you return home with a pile of sweaty clothes but don't have time to immediately wash them, make sure you hang your clothes up to dry instead of throwing them in a hamper or leaving them in your gym bag. Wet, sweaty gym clothes that remain in those piles for too long can actually start to breed mold and mildew spores that can be trapped in the fabric—even after washing!