Fitness Face Off: Cardio or Weights?

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It's a busy day and you've only got 30 minutes to squeeze in a workout. Should you run on the treadmill or lift weights? A new study in The American Journal of Physiology suggests cardio is the way to go for overweight people because aerobic exercise burns nearly 70 percent more calories than resistance weight training and seems to have more health benefits.

Researchers studied 196 overweight, sedentary people ages 18 to 70 over the course of a year to determine if cardio training, strength training, or a combination of the two would decrease fat and improve health. Their results determined that for overweight and obese individuals who want to reduce visceral (belly) fat and fatty liver infiltration and improve fasting insulin resistance, a moderate amount of aerobic exercise is the most time efficient and effective exercise mode.

So should you stop doing toning exercises?

"Cardio and strength-training are kind of like peanut butter and jelly -- you need them both," says Prevention fitness expert Chris Freytag, board member of the American Council on Exercise, and author of 2-Week Total Body Turnaround (Rodale).

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She says we need cardio to burn off calories and extra fat and to improve heart health.

"But strength-training is the long-term fix -- building muscle is the secret to keeping metabolism fired up. I believe the results of this study but I wouldn't recommend people stop strength-training.

"Because strength is the key to metabolism and we start to lose about a 1/2 pound of muscle per year after the age of 35, we need to replace it or we will get weak and our metabolism will slow down. Strength training also keeps your bones strong and makes you feel and look better."


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