To stay in shape， you only need to work out once or twice a week.
Truth： Once or twice a week wont cut it for sustained health benefits.
A minimum of three days per week for a structured exercise program is best.
Technically， you should do something every day， and by something I mean physical activity—just move. Because were finding more and more that the act of sitting counteracts any of the activity you do.
The best time to work out is the first thing in the morning.
Truth： The best time for a workout is whatever time allows you to exercise most consistently. Ideally， you want to make physical fitness a daily habit， so if late-night trips to the gym are your thing， stick with it. If you prefer a morning run， do that instead.
Weight lifting turns fat into muscle.
Truth： You cant turn fat into muscle. Physiologically speaking， theyre two different tissues. Fat tissue is found under the skin， sandwiched between muscles， and around internal organs like the heart.
What weight training really does is help build up the muscle tissue in and around any fat tissue.
Puzzles and games are the best “brain workout” around.
Truth： Plain old physical exercise seems to beat out any type of mental puzzle available， according to a wealth of research.
Studies suggest that aerobic exercise—any activity that raises your heart rate and gets you moving and sweating for a sustained period of time—has a significant， overwhelmingly beneficial impact on the brain.
Exercise is the best way to lose weight.
Truth： If youre looking to lose weight， you shouldnt assume that you can simply “work off” whatever you eat. Experts say slimming down almost always starts with changes to your eating habits.
“In terms of weight loss， diet plays a much bigger role than exercise，” University of Texas exercise scientist Philip Stanforth said.
Sit-ups are the best way to get six-pack abs.
Truth： As opposed to sit-ups， which target only your abdominal muscles， planks recruit several groups of muscles along your sides， front， and back. If you want a strong core—especially the kind that would give you six-pack-like definition—you need to challenge all of these muscles.
Weight training is for men.
Truth： Weight training is a great way to strengthen muscles， and has nothing to do with gender. However， women produce less testosterone （the male sex hormone） on average than men do， and studies suggest that hormone plays a role in determining how we build muscle. So its not going to be easy for women to build up strong muscle.
It takes at least two weeks to get “out of shape”.
Truth： In most people， muscle tissue can start to break down within a week without regular exercise.
If you stop training， you actually do get noticeable de-conditioning， or the beginnings of de-conditioning， with as little as seven days of complete rest.
Running a marathon is the ideal way to get fit.
Truth： Not ready to conquer a marathon？ No problem. You can get many of the benefits of long-distance running without ever passing the five-mile mark.
In fact， people who run for less than an hour a week—as long as they get in those few minutes each day—see similar benefits in terms of heart health compared to those who run more than three hours per week.
Sports drinks are the best way to re-hydrate after a workout.
Truth： Most sports drinks are just sugar and water.
Instead， experts recommend refuelling with plain old water and high-protein snack， since studies suggest protein helps recondition muscles after a workout.
workout /'w??ka?t/ n. 锻炼
She does a 20-minute workout every morning.
plain /ple?n/ adj. 极普通的;平凡的
You dont need any special skills for this job， just plain common sense.