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You're adding lean muscle. If you did a strength-training routine, your muscles are now starting to rebuild themselves and repair the microscopic tears that come with lifting weights, says Paul Gordon, PhD, director of the Laboratory for Physical Activity at the University of Michigan School of Medicine in Ann Arbor. Preliminary research shows that women respond to and recover from resistance training faster than men.


Model Amanda Wheeler is a certified strength and conditioning specialist (C.S.C.S.) and Precision Nutrition Level 1 Coach. She is the co-founder of Formation Strength, an online women’s training group that serves the LGBTQ community and allies by providing a space for individuals to uncover and enhance their highest potential through fitness, nutrition, and mindset.

Exercise has long been correlated with a longer life, but it’s only recently started to become clear why this might be. Studies, like a new one in the journal Preventive Medicine which found that exercise is linked to longer caps at the ends of chromosomes, have helped flesh this out a bit more. These caps, called telomeres, naturally shorten as we age, with each cell division. People who live a long time have telomeres that are in better shape than those who don’t—but there’s a lot we can do to affect the rate at which they shorten over the years. The team behind the new study looked at data from CDC's National Health and Nutrition Examination Survey, and found that for people who exercised regularly, their telomeres were 140 base pairs longer on average than sedentary people's. Which correlates to being years “younger” than their sedentary peers.


Feeling down on yourself? Exercising can help you feel better about yourself ­— no matter what type of workout you do or how fit you are. One study found that “the simple act of exercise and not fitness itself can convince you that you look better.” (10) With so much emphasis on our outward appearances in society today, it’s comforting to know that one of the benefits of exercise helps people feel better about themselves and how they look naturally.
This is a particularly cool one. Neuroscientists used to believe the brain was the only organ incapable of growing new cells—which partly makes sense, since we need our brains to be relatively stable over time, to keep our memories intact and to keep us us. But in recent years, it’s become clear that the brain, too, can grow new neurons, in a process called neurogenesis. And what seems to spur the growth of new neurons, perhaps above other activities, is aerobic exercise. (Other things, like meditation and antidepressant medication, have also been shown to trigger brain new cell growth.) The area of the brain that seems most capable of growing new cells is the hippocampus, the seat of learning and memory. It's also the area that’s known to “shrink” in depression, and particularly in dementia—so the fact that we may have some control over its health is exciting.
HOW TO DO IT: Start with your left leg forward and your right leg back. Place your left foot onto one end of a towel and grab the other end in your right hand. Pull the towel as hard as you can without holding your breath. Hold for 30 to 60 seconds, then switch sides and repeat. If you can’t maintain the hold continuously, break it up into shorter five- to 10-second bursts with brief one- or two-second rests in between.
Exercise has long been linked to better sleep, according to a review article published in December 2014 in the American Journal of Lifestyle Medicine. Other research suggests exercise may improve sleep and mood in people with insomnia, too, according to a study published in October 2015 in the Journal of Sleep Research. Conversely, poor quality sleep has been linked to a wide array of health problems, including cardiovascular disease, diabetes, and depression. Given the fact that getting adequate sleep is so crucial for good health, and that exercise is a low-cost, easily accessible solution that offers lots of other health benefits with no risk or side effects, giving exercise a try to improve sleep is a no-brainer.
Whether it’s a pick-up game of soccer, a group class at the gym, or just a run with a friend, exercise rarely happens in a bubble. And that’s good news for all of us. Studies show that most people perform better on aerobic tests when paired up with a workout buddy Aerobic exercise is promoted when individual performance affects the group: a test of the Kohler motivation gain effect. Irwin, B.C., Scorniaenchi, J., Kerr, N.L. et al. Kinesiology, Michigan State University, East Lansing, MI. Annals of Behavioral Medicine 2012;44(2):151-9.. Pin it to inspiration or good old-fashioned competition, nobody wants to let the other person down. In fact, being part of a team is so powerful that it can actually raise athletes’ tolerances for pain Rowers’ high: behavioural synchrony is correlated with elevated pain thresholds. Cohen EE, Ejsmond-Frey R, Knight N, Dunbar RI. Institute of Cognitive and Evolutionary Anthropology, University of Oxford, Oxford, UK. Biology Letters 2010 February 23;6(1):106-8.. Even fitness beginners can inspire each other to push harder during a sweat session, so find a workout buddy and get moving! Two-playered partner exergame for obesity prevention: using discrepancy in players’ abilities as a strategy to motivate physical activity. Feltz, D.L., Irwin, B., Kerr, N. Department of Kinesiology, Michigan State University, East Lansing, MI. Journal of Diabetes Science and Technology 2012; 6(4):820-7.
Below, you’ll find a core workout you can do at home, which was created by TruFusion trainer Alyssa West. Working all the muscles in your midsection—including the obliques (the muscles on the side of your body), rectus abdominis (what you think of as “abs”), transverse abdominis (your deepest internal core muscles), and yes, your glutes—is important for many reasons. “Working the [core] helps you maintain balance, good posture, and an overall strong [body],” says West. A solid core gives you a strong and sturdy foundation, which will help you move better in everyday life and be more successful in lifting heavier and pursuing other fitness-related goals. After all, most movements you do require some sort of core engagement to keep you stable, so the stronger these muscles are, the better.

Instead, focus on living the healthy, well-fueled and physically active lifestyle that you know you need to lead anyway. By doing that, you'll see far greater results in the arm department, anyway, Mendez says. Through a combination of balanced eating (hit all three macros at every meal!) and performing a combination of high-intensity interval cardio and strength training, you'll naturally shed fat all over, including around your arms, explains Lauren Williams, C.P.T., a trainer at PROJECT Equinox.
Step forward with the left foot and lower into a lunge, keeping the front knee behind the toe. Push into the heel to step back and immediately step out to the left and into a squat. Press back to start and take the left leg back into a reverse lunge, again keeping the front knee behind the toe. Bring the left leg back to start and repeat for all reps before switching sides.
This is a particularly cool one. Neuroscientists used to believe the brain was the only organ incapable of growing new cells—which partly makes sense, since we need our brains to be relatively stable over time, to keep our memories intact and to keep us us. But in recent years, it’s become clear that the brain, too, can grow new neurons, in a process called neurogenesis. And what seems to spur the growth of new neurons, perhaps above other activities, is aerobic exercise. (Other things, like meditation and antidepressant medication, have also been shown to trigger brain new cell growth.) The area of the brain that seems most capable of growing new cells is the hippocampus, the seat of learning and memory. It's also the area that’s known to “shrink” in depression, and particularly in dementia—so the fact that we may have some control over its health is exciting.
1. It strengthens the heart. The heart is a muscle. Like other muscles, its performance improves when it's regularly challenged by exercise. The heart responds to exercise by becoming stronger and more efficient. Strengthening the heart muscle can help ward off heart disease -- the leading cause of death in the United States, according to the U.S. Department of Health and Human Services -- even in early childhood. 
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