How to build muscle as age tears it down

By Dr. Melina B. Jampolis, CNN

Updated 0912 GMT (1712 HKT) March 6, 2018

Bad advice and outdated research could be putting a kink in your workout efforts. Here are some fitness myths that have proved to be just that.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – Bad advice and outdated research could be putting a kink in your workout efforts. Here are some fitness myths that have proved to be just that.
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Crunches do tone a small portion of your abs, but you may get better results from moves engaging your entire core.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – Crunches do tone a small portion of your abs, but you may get better results from moves engaging your entire core.
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Sweating doesn't equate to calories burned. It might be the result of a hot room, the weather or your physiology.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – Sweating doesn't equate to calories burned. It might be the result of a hot room, the weather or your physiology.
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Running is safer on your joints than contact sports, but it's not totally harmless. A total-body workout at least twice a week along with regular jogs can build up muscles supporting the knees.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – Running is safer on your joints than contact sports, but it's not totally harmless. A total-body workout at least twice a week along with regular jogs can build up muscles supporting the knees.
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Stretching after exercise won't completely reduce soreness or speed muscle tissue repair, but can increase joint flexibility.
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Fitness: Myths vs. facts – Stretching after exercise won't completely reduce soreness or speed muscle tissue repair, but can increase joint flexibility.
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More and more studies are pointing to the power of short workouts rather than longer ones. Some research even suggests quickie sessions might be better.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – More and more studies are pointing to the power of short workouts rather than longer ones. Some research even suggests quickie sessions might be better.
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Scheduling rest days is crucial. Working out every day can lead to injury or overtraining, which keeps your muscles from rebounding and your body from improving.
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Fitness: Myths vs. facts – Scheduling rest days is crucial. Working out every day can lead to injury or overtraining, which keeps your muscles from rebounding and your body from improving.
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Research has shown that skipping sleep may lead to weight gain. Even partial sleep deprivation ups production of the hormone ghrelin, which triggers hunger.
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Fitness: Myths vs. facts – Research has shown that skipping sleep may lead to weight gain. Even partial sleep deprivation ups production of the hormone ghrelin, which triggers hunger.
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Yoga improves strength and flexibility, but it doesn't burn as many calories as aerobic exercise, researchers say.
Photos: Fitness myth or fact?
Fitness: Myths vs. facts – Yoga improves strength and flexibility, but it doesn't burn as many calories as aerobic exercise, researchers say.
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Women have less muscle tissue and produce lower levels of testosterone than men, so they're less likely to bulk up from lifting weights.
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Fitness: Myths vs. facts – Women have less muscle tissue and produce lower levels of testosterone than men, so they're less likely to bulk up from lifting weights.
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