Do This, Not That! 40 Mistakes to Miss

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This, Not That!: Hits and Myths

Believe This!
Slow lifting produces superlong workouts—and that’s it.

Not That!
Slow lifting builds huge muscles.



Believe This!
Stretching during a warmup has little effect on injury prevention.

Not That!
Stretching prevents injuries.


"Stretching increases flexibility, but most injuries occur within the normal range of motion," says Julie Gilchrist, M.D., one of the study's researchers. "Stretching and warming up have just gone together for decades. It's simply what's done, and it hasn't been approached through rigorous science."

The real expert says: Warming up is what prevents injury, by slowly increasing your bloodflow and giving your muscles a chance to prepare for the upcoming activity. To this end, Dr. Gilchrist suggests a thorough warmup, as well as conditioning for your particular sport.

Of course, flexibility is a good thing. If you need to increase yours so it's in the normal range (touching your toes without bending your knees, for instance), do your stretching when your muscles are already warm.

Believe This!
People with normal blood pressure do not need to restrict sodium intake.

Not That!
Salt causes high blood pressure.

Large-scale scientific reviews have determined there's no reason for people with normal blood pressure to restrict their sodium intake. Now, if you already have high blood pressure, you may be "salt sensitive." As a result, reducing the amount of salt you eat could be helpful.

However, it's been known for the past 20 years that people with high blood pressure who don't want to lower their salt intake can simply consume more potassium-containing foods. Why? Because it's really the balance of the two minerals that matters. In fact, Dutch researchers determined that a low potassium intake has the same impact on your blood pressure as high salt consumption does. And it turns out, the average guy consumes 3,100 milligrams (mg) of potassium a day—1,600 mg less than recommended.

