#1: Squeeze out the air in the condom's tip when you're putting it on
The banana condom demos clearly aren't cutting it.
According to a 2012 Kinsey Institute review, men tend to make these mistakes: They either forget to leave space for their semen to collect at the condom's tip, or if they do leave a little room in their rubber, they fail to squeeze out the air. Both can increase your risk of breakage.
So what's the proper technique for gloving up?
To leave space and remove the air, use your thumb and forefinger to squeeze the tip as you're rolling the condom down all the way to the base of your penis," says study author Robin Milhausen, PhD.
#2: Don't wash your hands after applying sunscreen
This is one time you don't want to wash your hands. If you suds up after slathering on sunscreen, you leave a crucial surface exposed to harmful UV rays.
I frequently see accelerated ageing on the hands because people forget to apply sunscreen there," says dermatologist Dr Amy Derick.
Apply about as much sunscreen to your hands as you would if you were moisturising with lotion.
And don't forget your nails. Yes, they're dead cells, but the tissue underneath is active and susceptible to melanoma and other skin cancers, the Skin Cancer Foundation in the US warns.
#3: Check to make sure your cleaners disinfect
That blue stuff you spray on your windows may be great on glass, but it's a dud as a disinfectant. Scan the label before you buy: Only cleaners labelled as germ killers will disinfect.
"If you use a cleaner that's not a disinfectant, you run the risk of not killing bacteria, spreading microbes and contaminating more surfaces," says University of Arizona micro-biologist Charles Gerba, PhD.
Once you start cleaning, step away after you spray. "It takes 30 to 90 seconds for a disinfectant to kill germs, so let it sit before wiping it off," Gerba says.
#4: Think twice about taking a shower every day
Unless you punch the clock in a sewer pipe, you're probably overdoing it. "The outermost layer of skin is essential for locking in moisture," says Dr Derick.
Frequent showers with serious scrubbing can remove the layer's oils and lipids, which help fend off dryness.
Shower every day if you need to - just keep the water lukewarm and your time to 10 minutes or less, Dr Derick says.
Afterwards, skip the vigorous towel-dry routine. Instead, gently blot your body with a soft towel and smear on a moisturising cream that contains skin-fortifying fatty acids, says Dr Derick.
#5: Avoid reusing contact lens solution
If you never changed your car's oil and only topped it off, you'd end up with an engine full of dirty oil. Well, you're practising the same poor maintenance with your contacts.
In a University of Texas study, 90 per cent of people thought using fresh solution meant simply adding a few drops to what was already in the lens case.
The harm? Leftover solution is sapped of its disinfecting power, which can raise your risk of vision-damaging infections.
Your move: Clean, rinse and air-dry the case each time you remove your lenses from it. Then refill it with fresh solution.
#6: Change lubricant when trying to make a baby
You love the idea of having sex like clockwork. But for your wife, having to hook up whenever she's ovulating - horny or not - can make her wish your Big Ben would break.
"Three out of four women report increased vaginal dryness when they're trying to conceive," says Ashok Agarwal, PhD, director of research at the Cleveland Clinic's centre for reproductive medicine in the US.
Unfortunately, a lube may alter the pH of her vagina and act like a spermicide, he warns. Stick to those that say "safe for use when trying to conceive," says Dr Agarwal.
#7: Squat, don't sit in the toilet
Even if you're a fan of fibre, you can still find yourself straining on the toilet.
Most commodes are now "comfort height," which means your knees are level with your hips. This puts a crook in your rectal canal, interfering with the smooth transit of your turds.
"In the natural squatting posture, with your butt below your knees, the rectal angle is straighter, minimizing straining," says Dr Dov Sikirov, the author of an Israeli study on the topic.
To help straighten your canal, place a 10cm footstool under your feet. In the study, people who did this strained less.
#8: Get off the couch
"Lying down for a prolonged period of time is one of the worst things you can do for low-back pain," says Dr Carmen Pichard-Encina of Johns Hopkins Medicine.
"It increases stiffness in the muscles of your back. Over time, inactivity can also cause them to weaken, making them even more prone to injury and pain." This doesn't mean you should exercise as normal, though.
Opt for low-impact activities, such as walking or swimming, which target muscle stiffness without jolting your joints, says Dr Pichard-Encina.
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