Exercise can do some weird things to your body. We took a look at every angle—from mental health to digestion to immunity—to find all the weird side effects of working out: the good, the bad, and the ugly.
Want to tack on three years to your life, prevent a bout of the “runs,” or learn to avoid nipple chafing (who wouldn’t)? Read on.
1. Bolsters Flu Shot Response
Doing 90 minutes of moderately paced cardio right after your flu shot could make the vaccine work better. Research found that participants who cycled or ran 15 minutes after being vaccinated had nearly double the antibody response compared to volunteers who were sedentary after the flu shot.
Aerobic activity speeds up circulation, helping the vaccine travel away from the injection site, and toward other parts of the body. But make sure you hit 90 minutes to get the maximum benefit. Think that’s torture? Watch a movie on the treadmill, or imagine how awful it’ll be to have the flu. That should keep you moving.
2. Helps You Hold It
If your night’s sleep isn’t complete without a trip to the bathroom, you may benefit from this weird side effect. Men who are physically active are at a lower risk of “nocturia,” a.k.a. waking up at night to pee. The 2014 study, published in Medicine & Science in Sports & Exercise, analyzed over 30,000 men with enlarged prostates—one of the main causes of nocturia. Those who were physically active one or more hours per week were 13% less likely to report nocturia and 34% less likely to report severe nocturia (waking up three or more times.)
3. Fights Wrinkles
Exercise can keep skin looking younger, and may even reverse the effects of aging in people who start working out later on in life. Men and women over the age of 40 were put on an endurance-training regimen; they worked out twice a week, either jogging or cycling at a moderately strenuous pace for 30 minutes over the span of three months. In the end, these individuals’ skin compositions were comparable to that of 20- and 30-year-olds—even if they were past the age of 65. Findings came from McMaster University in Ontario, which were reported in The New York Times. Some words of wisdom: keep moving, it may just be the best way to fight wrinkles.
4. Irritates Your Nipples
So you’re new to marathons. Want to know what’s a dead giveaway? Your nipples are bleeding down your sweaty white T-shirt. This is common in novice endurance runners; experienced athletes have come across a wondrous invention called NipGuards. Tips for the novice runner: you can use cheaper alternatives like Band-Aids, and a generous helping of BodyGlide or Vaseline. Also, stick to tighter shirts that, well, stick close to your body so the dried salt from your sweat doesn’t chafe against your skin like sandpaper. It’s that or wearing a sports bra. The choice is yours.
5. Can Bring on Exercise-Induced Anaphylaxis
You expect some huffing and puffing from a workout, but nothing quite prepares you for an impromptu episode of anaphylaxis. During physical exertion, the body’s mast cells (immune system tissue) release histamine, the compound responsible for the swelling and itching associated with allergic reactions, which triggers symptoms like hives, difficulty breathing, wheezing, and nausea.
Some advice: EIA is usually associated with foods like celery, shellfish, and peanuts, so if you’re sensitive, avoid eating these trigger foods before a workout, take an antihistamine, and ease into small amounts of regular exercise to build up your body’s tolerance.
6. Gives You the Runs
Nothing ruins a morning run quite like, well, a case of “the runs.” (Side note: anyone who says this hasn’t happened to them is lying.) There’s a lot happening when you run. Your organs are jostled; there’s a decrease in blood flow to the intestines as it’s pumped to your moving muscles; there are changes in intestinal hormone secretion. All the gears are churning to create the perfect storm in your bowels.
The Mayo Clinic suggests avoiding sweeteners and high-fiber food the day before, and caffeine three to six hours before. Also make sure you hydrate before, during, and after your run. Knowing where nearby public restrooms are helps. So does wearing thick socks (you know, in case of emergency).
7. Makes You Thirsty (for Booze)
Find yourself consistently drinking beer after a hard workout on the track, or craving a Jack and Coke after your last rep? It’s more common to consume alcohol after you exercise, researchers from Northwestern University found in a September 2014 study.
It’s not that people who exercise drink more; it’s that people generally drink more on days they’re physically active, which tends to be when the “social weekend” kicks off: Thursday through Sunday. One theory is that people may reward themselves for exercising by having more to drink, or the exercise triggers a desire to be more social and interact where alcohol is consumed. Not a bad correlation if you ask us.
8. But Also Reverses Alcohol Damage
Regular cardio workouts can reverse the damaging effects of alcohol on your brain, according to a 2013 study published in Alcoholism: Clinical & Experimental Research. Though the researchers didn’t provide a formula for offsetting your weekend binges, they are hopeful that getting your heart rate up every day can prevent and repair damaged white matter, which controls learning, cognition, and communication. Bottoms up.
9. Cheers You Up
“Walk it off” is more than just an idiom like “rub some dirt in it”—it can actually make you happy. A 30-minute walk can boost your mood and tackle depression, a 2010 study published in the Medicine & Science in Sports and Exercise found. Individuals experience fewer feelings of negativity, tension, anger, and fatigue, experiencing bouts of good feelings such as vigor and well-being instead.
Exercise releases growth hormones, which increase the supply of oxygen and blood to the brain, stimulating feel-good, mood-enhancing endorphins. These endorphins have the ability to create euphoria and relief from pain better than morphine. Guess working out is the true happy pill after all.
10. Boosts Brain Power
The more you exercise in your youth, the better your brain will function in the future. Young adults with a higher cardiovascular fitness level performed better on cognitive tests given 25 years later compared to their less-fit counterparts, a 2014 study published in Neurology found.
What’s more, a 2013 Journal of Strength and Conditioning Research study found that six weeks of agility training significantly improves attention span and memory. Stay sharp, my friends.
11. Cuts Cravings
You know that bag of Doritos you keep plunging your hands into, fueling a lava-orange cheese binge that just can’t be relinquished? Put it down for good with advice published in the American Journal of Clinical Nutrition. Researchers found that an hour of running suppresses junk-food cravings. MRI scans showed that parts of the brain, which control appetite, lit up when viewing low-calorie foods—considering them rewarding and thereby suppressing the desire for high-calorie foods.
12. Prevents Seasonal Depression
Seasonal depression may have never affected you before. But winters that include events like last year’s polar vortex will give anyone the blues. Exercise, though, can combat that. Exercising 30 minutes a day can help you feel better and gain energy. Walking outside in the sun (bonus if it’s warm) will also help mental health.
13. Erodes Tooth Enamel
You’ve been working hard in the gym to strengthen your body and improve your health, but the fruits of your labor are rotten. Turns out athletes have more eroded tooth enamel than individuals who are sedentary, a 2014 study published in the Scandinavian Journal of Medicine & Science in Sports found. When you work out, saliva production decreases, causing your mouth to become drier and alkaline levels in your saliva to increase; this boosts your chances of developing cavities. Endurance athletes beware, intense training can be detrimental to oral health.
14. Eases Asthma
Certain exercise programs can strengthen the heart and lungs, in addition to improving overall quality of life according to a review published in The Cochrane Library. Nearly 800 people over 21 comprehensive studies performed aerobic exercise for 20 to 30 minutes a day two to three times a week for six to 16 weeks. Individuals with asthma were able to increase their workload and cardiovascular fitness measured by maximum oxygen uptake. No participants experienced reactions or worsening of respiratory health. Something to breathe easy about.
15. Prolongs Life
Who wants to live longer? Everyone, obviously. Who loves running? Numbers drastically drop. But that’s OK. Here’s why:
Running every day for up to 10 minutes can boost your health just as much as hitting the pavement for an hour. There’s hope for humanity. The Journal of the American College of Cardiology suggests running, regardless of speed, can tack on three years to your life.
16. Stresses the Heart
Exercise in moderation is a tried and true mantra that you should take seriously. Extreme workouts can damage your heart. The benefits of exercise decreases for runners who log more than 20 miles a week, and for those who run faster than eight miles per hour, according to a 2012 study published in the journal Heart. Critics have refuted this, but one thing is certain: it’s never a bad idea to see your doctor regularly to make sure your workouts are benefiting your health.
17. Improves Memory
Don’t skip leg day. Performing a weighted two-legged squat can have memory-enhancing effects on your brain, researchers at Georgia Institute of Technology suggest in a 2014 study. A group of individuals were asked to recall images after lifting weights, while others did so without exercise. Surprisingly enough, exercisers remembered 10 percent more images than non-exercisers after they did 6 sets of 10 reps of leg extensions.
18. Leads to More Sex
Couples who run together, have more sex together. Hey, it’s science.
A Brooks Running survey of 1,000 adults revealed that 66% of runners believe they have more sex when they run with their significant others. It’s not just a jog around the block, or a walk through the park, though. The more miles you cover, the larger the payoff is between the sheets. Just how many? According to the survey, 49% of couples who ran six or more miles together claimed their sweat sesh made their other sweat sesh better.
19. Balances Your Gut
You may not know much about your gut, aside from the fact that you have one. But exercise can have a beneficial effect on the bacteria found there. An analysis of professional rugby players showed that these athletes had a more diverse collection of bacteria in their digestive system compared to non-athletes of similar size and age. Greater microbial diversity is linked with better health in older adults, while a loss of diversity is linked to obesity, inflammatory bowel disease, and autism.
20. Propels Your Career
If you’re like most American workers, you spend most of your day sitting, which increases your chance of illness and injury. But a study from ACE Fit showed that a daily, supervised 10-minute stretching program among assembly-line workers showed significant improvements in flexibility and fatigue, and improved anger, depression, and overall mood. Likewise, a study of 80 executives who exercised showed a 70% improvement in their ability to make complex decisions.
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