9 Pieces of Exercise Advice You Can Ignore

Much of the fitness advice you hear may be sound, but some is bogus — or downright dangerous.
Much of the fitness advice you hear may be sound, but some is bogus — or downright dangerous.

1. The Best Time to Exercise
Myth: Early morning is the best time to exercise.
Fact: "The best time to exercise is anytime you can do it," says Delia Hammock, M.S., R.D., and former Nutrition Director at the Good Housekeeping Research Institute. So whether you have more energy in the morning or at night, the important thing is that you motivate yourself to do it.

Related: 4 Lame Excuses You Use to Avoid Working Out

2. Targeting Your Abs
Myth: You should spend 30 minutes of your workout on your abs.
Fact: Done properly, a mere five-minute ab routine is enough to make muscles feel fatigued -- the goal of your workout, says exercise physiologist and American Council on Exercise (ACE) spokesperson Richard Cotton. After that, switch to cardiovascular activities like walking, swimming, or biking. These activities work all the major muscles, melting fat and giving you an overall leaner appearance.

3. The Benefits of Protein Bars and Shakes
Myth: It's smart to eat lots of protein bars and shakes, so you can build your muscles.
Fact: The only thing that increases muscle mass is exercise. For that, you need energy-providing carbohydrates, not extra protein, says Nancy Clark, R.D., of SportsMedicine Associates, in Brookline, Mass. A good diet for a recreational exerciser consists of 55 to 65% carbs and about 60 to 90 grams of protein a day.

4. The Right Weights to Lift
Myth: Lifting heavy weights will overdevelop a woman's muscles.
Fact: Women don't have the hormones needed to develop masculine physiques, says ACE's Ken Alan. The heavier the weights, the stronger your muscles -- which means that you'll burn calories more efficiently.

Related: 7 Surprising Workout Mistakes You Don't Know You're Making

5. A Stair Climber Trick
Myth:Lean forward on the stair climber if you want a firm butt.
Fact: Do this, and you could strain your lower back. Instead, stand tall and rest your hands on the rails just enough to balance.

6. Magical Pills
Myth: For extra energy, pop a metabolism-boosting pill.
Fact: Unregulated herbal supplements that contain ephedra, or Mau Huang, can cause dizziness and insomnia, increase your blood pressure and heart rate, and may be linked to strokes. If you're running on empty, get more sleep and eat regularly.

7. Drinking Special Water
Myth: Drink "super oxygenated" water and you'll increase the amount of oxygen in your blood and get more energy.
Fact: There is no evidence that this works, reports ACE. A study by this group found that this type of water had no measurable effect on subjects' heart rate, blood pressure, or blood lactate values. Any increased energy levels, the study concluded, is purely a placebo effect.

Related: The Ultimate List of Reasons Why You Should Be Exercising

8. How Long You Should Work Out
Myth: Your body won't burn fat unless you exercise for more than 20 minutes.
Fact: You burn fat around the clock, whether you're exercising or not. For the biggest calorie burn, exercise as hard as you comfortably can (you should still be able to carry on a conversation) for as long as you can.

9. When You Shouldn't Drink Water
Myth: Avoid drinking water when you exercise or you'll get cramps.
Fact: Water is essential for staying properly hydrated while you work out. "You need water before, during, and after you exercise," says Hammock. When you sweat a lot, your body loses even more water than normal. And in summer months, drinking water is essential, because you are at a higher risk for heat exhaustion.

-Samantha Cassetty, M.S., R.D.

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