By GRETCHEN REYNOLDS

Illustration by Ben Wiseman

January is the cruelest month, at least for those with good intentions to get fit. According to recent analyses of decades’ worth of exercise studies, many new exercise “intenders” will abandon their workout routines within two weeks of their New Year’s resolutions, and about half will quit by June. Even longtime exercisers feel the pull of physical entropy. In any given year, around a quarter of the people who had been working out dutifully will stop. (And about 2 percent of those who claim to have no intention of exercising actually start and continue, baffling researchers and possibly the exercisers themselves.)

Why we fail to realize our best exercise intentions is a complex interplay of psychology, physiology and genetics. Adult twins frequently have similar exercise patterns, suggesting that some portion of exercise motivation is inherited. Innate personality also plays a role, according to one of the new reviews published last fall in the British Journal of Sports Medicine. Being extroverted makes it easier to stick with exercise resolutions, while being nice (or “agreeable,” in psychological terms) does not.

But most quit exercising for more commonplace — and redressable — reasons. For instance, people make generic or unrealistic plans about where and when they will exercise, making them essentially fairy-tale wishes, says Ryan Rhodes, a professor of behavioral medicine at the University of Victoria in British Columbia, who has co-written several recent reviews and conducted numerous exercise-intention experiments.

“Someone can plan to go to the gym Friday at 5:30 a.m. before work,” he says, but if he or she hates early rising or prebreakfast exertion, those plans will evaporate. What Dr. Rhodes describes as a “far more detailed strategy” that concretely addresses specific obstacles (Which bus runs at 5:30 a.m.? Gym bag packed and next to the door?) is more likely to motivate behavior. Also gauge “your daily fatigue and schedule exercise during times when you feel best,” he advises.

But the most important factor when it comes to sticking with exercise is so obvious that it frequently goes unheeded. The appeals of physical fitness — good health, pleasing appearance, appropriate body weight — are vague and distant, and “the actual experience of exercise is not given much consideration,” Dr. Rhodes says. In other words, we don’t think about whether we like exercise before we embark on a regimen, yet our feelings about exercise predict “who translates their intentions into behavior,” as Dr. Rhodes puts it.

So the first consideration is finding your exercise bliss. Typically this includes variety, novelty and competence. People who feel ungainly in a Zumba class won’t keep attending.

Rewards, furthermore, are of limited value. Promise yourself an hour of television after 30 minutes of walking through the neighborhood, and the walk can seem more pleasurable. But naked greed is not much of a motivator. In a study published last year in Preventive Medicine, 117 college freshmen agreed to visit their school’s gym on a regular schedule. Some were then paid at least $10 weekly if they complied. After four months, the for-profit exercisers had visited the facility more times in total than the other students, but only 63 percent met the original agreed-upon goals, and everyone’s attendance had fallen off week by week. Even for the notoriously impecunious, cash cannot overcome lack of interest.

By NICHOLAS BAKALAR

A new clinical trial suggests that a daily dose of a probiotic may ease digestive upset in babies.

Italian researchers randomly assigned 468 infants less than a week old to receive either a daily oral dose of Lactobacillus reuteri or an identical tasting placebo. Parents recorded the daily frequency of bowel movements and spitting up as well as the amount of time babies cried inconsolably. Investigators followed the families with weekly phone calls or personal meetings. The study appears online in JAMA Pediatrics.

After one month, the babies who got the probiotic showed a significant decrease in crying time and an increase in frequency of bowel movements compared with those who got the placebo. By three months, their frequency of spitting up was reduced as well.

The babies taking the probiotic had fewer emergency department visits and needed less medication for stomach problems. Their parents lost fewer days of work, and there were no adverse side effects. The results were adjusted to account for the effects of breast or bottle feeding, vaginal or cesarean delivery, and other factors.

Lactobacillus occurs naturally in humans, and the lead author, Dr. Flavia Indrio, a pediatric gastroenterologist at the University of Bari in Italy, said that there are thousands of strains available as supplements. But the only one tested in clinical trials was the one used in this study, called L. reuteri DSM 17938, she said.

“The probiotic has to be given in the right dose,” she said. “I do not recommend using it without consulting a pediatrician.”

Ask Well: How Long Does a Flu Shot Last?

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Q

How long is flu vaccination effective?

Reader Question • 2 votes

A

Flu vaccines are different from vaccines for other diseases, such as measles, because they are given every year. The chief reason, experts say, is not that the vaccine wears off, but that flu viruses mutate so fast as they move around the world. The flu shot or nasal mist — which now may contain up to four separate vaccines against four separate influenza viruses — must be reformulated every year in an effort to match the most common circulating strains.

How long your own flu shot lasts depends on how powerfully your own immune system reacts to it, said Dr. John J. Treanor, a vaccine expert at the University of Rochester medical school. In a young, healthy person, protection might last for years, even as circulating flu strains change. Conversely, he said, there is some debate about whether older people or those with compromised immune systems ought to get two flu shots per season, since a shot they got in October may wear off by March or April.

“It’s a controversial question, and there’s not a lot of direct data on it,” Dr. Treanor said.

The need for repeat vaccinations is different for each disease, he added. Two measles shots in childhood usually give lifelong protection. Tetanus shots should be repeated every 10 years or so. Pertussis, or whooping cough, shots are moving in that direction as well, since a new vaccine with fewer side effects that was introduced the 1990s gives shorter-lived protection.

Fitting in fitness at home

Fitting in fitness: Finding time for physical activity

Finding time for fitness can be tough. The key is making it convenient. Consider these practical suggestions. By Mayo Clinic Staff

You know fitness is important for your health and well-being. And you want to get more active, but your days are a blur of work, household chores, errands, and time with family and friends. Setting aside enough time to sleep — let alone exercise — can be tough.

So how can you find time for fitness? The key is to be flexible and make fitness a way of life. And remember all physical activity — not just formal exercise programs — adds up to a healthier you.

Time spent at home doesn’t have to be “couch potato” time. To make fitness a priority at home:

• Wake up early. Get up 30 minutes earlier than you normally do and use the extra time to walk on your treadmill or take a brisk walk around the neighborhood.
• Make chores count. Mop the floor, scrub the bathtub or do other housework at a pace fast enough to get your heart pumping. Outdoor work counts, too. Mowing the lawn with a push mower is a great way to burn calories. Raking and hoeing strengthen your arms and back, and digging works your arms and legs.
• Be active while watching TV. Use hand weights, ride a stationary bike or do a stretching routine during your favorite shows. Get off the couch to change the channel or adjust the volume.
• Involve the whole family. Take group walks before or after dinner. Play catch. Ride your bikes. It’s best to build up to about 30 minutes of continuous activity, but you can exercise in shorter bursts, too.
• Get your dog into the act. Take daily walks with Fido or Fluffy. If you don’t have a dog, borrow one. An enthusiastic dog may give you the motivation you need to lace up your walking shoes.

Work out at work

To fit in more physical activity while you’re on the job:

• Make the most of your commute. Walk or bike to work. If you ride the bus, get off a few blocks early and walk the rest of the way.
• Take the stairs whenever you can. If you have a meeting on another floor, get off the elevator a few floors early and use the stairs. Better yet, skip the elevator entirely.
• Take fitness breaks. Rather than hanging out in the lounge with coffee or a snack, take a short walk.
• Start a lunchtime walking group. The regular routine and the support of your co-workers may help you stick with the program.
• Put it on the calendar. Schedule physical activity as you would any other appointment during the day. Don’t change your exercise plans for every interruption that comes along.
• Take it on the road. If you travel for work, plan ahead. Bring your jump-rope or choose a hotel that has fitness facilities. If you’re stuck in an airport waiting for a plane, grab your bags and take a walk.

More tips for fitting in fitness

Here are a few more ways you can add more activity to your routine:

• Get more out of errands. When you go to the mall or grocery store, park toward the back of the lot and walk the extra distance. If you have a little extra time, walk inside for a lap or two before you start shopping. Keep a pair of walking shoes in your car so that you’re ready when you find a few minutes for exercise.
• Plan active outings. Make a date with a friend to hike in a local park, or take a family trip to the zoo.
• Get social. Try a dance club, hiking group or golf league. Encouragement from others can help you stay with a new activity.
• Join a team. Sign up for a softball, soccer or volleyball team through your local parks and recreation department. Making a commitment to a team is a great motivator.
• Join a fitness club. Sign up for a group exercise class at a nearby fitness club. The cost may be an added incentive to stick with it.

There’s no single best way to fit physical activity into your day. Your lifestyle, job and family responsibilities will point to the most convenient time and place for fitness. Do what works for you — and make daily physical activity a habit you keep.

Evaluate how you react to stress

Stress management starts with an honest assessment of how you react to stress. You can then counter unhealthy ways of reacting with more-helpful techniques. By Mayo Clinic Staff

It’s hard to avoid stress these days with so many competing demands for your time and attention. But with good stress management skills, you can cope with stress in a healthy way.

One of the first steps toward good stress management is understanding how you react to stress — and making changes if necessary. Take an honest look at how you react to stress and then adopt or modify stress management techniques to make sure the stress in your life doesn’t lead to health problems.

Stress management skills often don’t come naturally. You can learn new stress management skills or modify your existing stress management skills to help you cope better, though.

First, take a look at how you react to stress. Some people seem to take everything in stride. Their naturally laid-back attitudes shine through, even in stressful situations. Another deadline? Bring it on. The dishwasher is leaking? No problem, it’ll be a simple repair. Others get anxious at the first sign of a stressful situation. Running late for a meeting? Time to panic! Stuck in a traffic jam? Let the cursing begin!

Here are some common but unhealthy reactions to stress. Do any of these describe your reactions? If you’re not sure, consider keeping a daily journal for a week or so to monitor your reactions to stressful situations.

• Pain. You may unconsciously clench your jaws or fists or develop muscle tension, especially in your neck and shoulders, all of which can lead to unexplained physical pain. Stress also may cause a variety of other health ailments, including upset stomach, shortness of breath, back pain, headaches and insomnia.
• Overeating. Stress may trigger you to eat even when you’re not hungry, or you may skip exercise. In contrast, you may eat less, actually losing weight when under more stress.
• Anger. Stress may leave you with a short fuse. When you’re under pressure, you may find yourself arguing with co-workers, friends or loved ones — sometimes with little provocation or about things that have nothing to do with your stressful situation.
• Crying. Stress may trigger crying jags, sometimes seemingly without warning. Little things unrelated to your stress may leave you in tears. You also may feel lonely or isolated.
• Depression. Sometimes stress may be too much to take. You might avoid the problem, call in sick to work, feel hopeless or simply give up. Chronic stress can be a factor in the development of depression or anxiety disorders.
• Negativity. When you don’t cope well with stress, you may automatically expect the worst or magnify the negative aspects of any undesirable situation.
• Smoking. Even if you quit smoking long ago, a cigarette may seem like an easy way to relax when you’re under pressure. In fact, stress is a leading cause of having a smoking relapse. You may also find yourself turning to alcohol or drugs to numb the effects of stress.

Once you’ve identified the unhealthy reactions you may be having to uncontrolled stress, you can begin to improve your stress management skills. Stress management techniques abound, including:

• Scale back. Cut back on your obligations when possible. While it may seem easier said than done, take a close look at your daily, weekly and monthly schedule and find meetings, activities, dinners or chores that you can cut back on or delegate to someone else.
• Prepare. Stay ahead of stress by preparing for meetings or trips, scheduling your time better, and setting realistic goals for tasks both big and small. Stress mounts when you run out of time because something comes up that you didn’t account for — build in time for traffic jams, for example.
• Reach out. Make or renew connections with others. Surrounding yourself with supportive family, friends, co-workers, or clergy and spiritual leaders can have a positive effect on your mental well-being and your ability to cope with stress. Volunteer in your community.
• Take up a hobby. It may seem cliche, but when you engage in something enjoyable, it can soothe and calm your restless mind. Try reading, gardening, crafts, tinkering with electronics, fishing, carpentry, music — things that you don’t get competitive or more stressed out about.
• Relax. Physical activity, meditation, yoga, massage and other relaxation techniques can help you manage stress. It doesn’t matter which relaxation technique you choose. What matters is refocusing your attention to something calming and increasing awareness of your body.
• Get enough sleep. Lack of sufficient sleep affects your immune system and your judgment and makes you more likely to snap over minor irritations. Most people need seven to eight hours of sleep a day.
• Get professional help. If your stress management efforts aren’t helpful enough, see your doctor. Chronic, uncontrolled stress can lead to a variety of potentially serious health problems, including depression and pain.

Stress usually doesn’t just magically get better on its own. You may have to actively work on getting control of the stress in your life so that it doesn’t control you. When you first identify how you react to stressful situations, you then can put yourself in a better position to manage the stress, even if you can’t eliminate it. And if your current efforts at stress management aren’t working, try something new.