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Slimming down isn’t an art—it’s a science. And if you don’t know your fiction from your facts, you’re setting yourself up for a whole lot of (totally unnecessary!) frustration. If you want to run to lose weight, separate the truth from the myths.
FICTION: If you run more, you’ll lose weight.
The Science: Two studies, including one published in the International Journal of Sports Nutrition showed an additional 45 to 50 minutes of moderate aerobic exercise five days a week had no effect over dieting alone over a 12-week or 6-month period. Since your body can adapt to this kind of exercise quickly, you burn fewer and fewer calories as you progress in your training.
FACT: Add weight training to shed pounds.
The Science: A study published in the journal Medicine & Science in Sports & Exercise followed three groups. One group dieted, the second dieted and did aerobic exercise and the third combined dieting, aerobics and weight training. Over 12 weeks, the third group lost the most weight by far—an average additional loss of 5 pounds of fat per person!
FICTION: Run longer in order to get the weight-loss benefits.
The Science: The American Journal of Physiology did a study with two groups training either 30 or 60 minutes a day; the half-hour exercisers lost 8.8 pounds of fat, while the hour-long group lost 8.4 pounds. The research lead on the report suggested longer runs can result in increased hunger, which offsets the extra work.
FACT: Circuit training is better.
The Science: A team of researchers in Spain and Australia compared circuit training (i.e., moving quickly from one strength exercise to the other) to traditional straight sets (resting between each exercise) and found you burn more calories during and after the workout if you choose the circuit style.
FICTION: If you eat less and move more, you’ll definitely lose weight.
The Science: This idea that weight loss is all about creating a caloric deficit is simply not the whole truth. The effort doesn’t always match the payoff. For example, athletes running the “Marathon of Sands” in Morocco, which includes a marathon every day for six days, lost an average of only 6.1 percent of their body weight—and mostly from muscle tissue.
FACT: Shorter, high-intensity training is key.
The Science: One study in Medicine & Science in Sports & Exercise split participants into two groups, doing either interval training (think: hill sprints) or steady-state endurance training (long, slow runs). Fat loss was 114 percent higher with the interval-training group!
Related: Running For Weight Loss Plan
The best time of day to work out is different for each person. But when it comes to weight loss, the science says early birds have the edge for a few reasons…
- Exercise can boost your willpower the rest of the day.
- You get your metabolism revving to burn more calories the rest of the day.
- You will be less likely to come up with excuses to skip your workout.
That said, if your body needs a few hours to get going, and you feel more focused and ready to work out later, save it for the afternoon.
My Beating Heart
To figure out your target heart rate while following our Weight-Loss Plan, use these simple equations:
- 220 – Your Age = Max Heart Rate
- Max Heart Rate x 0.85 = 85% of Max Heart Rate (work interval)
- Max Heart Rate x 0.70 = 70% of Max Heart Rate (recovery target)
These are estimates and may need to be adjusted as you go. To determine how accurate the equations are without a heart-rate monitor, follow this guide…
- Below 70% — Can sing a song
- 70–85% — Can talk and as approaching the top only in two- or three-word sentences
- 85% or higher — Grunts only