The Women's Health Big Book of 15-Minute Workouts: A Leaner, Sexier, Healthier You--In 15 Minutes a Day! (3 page)

The benefits don’t stop at weight loss. HIIT workouts also help you get fitter faster (so you have more energy for everything you love to do). In a striking head-to-head showdown, Canadian researchers found that a group of exercisers who cranked out short stationary bike workouts that included a series of 30-second sprints 3 days a week improved their fitness by about 30 percent—nearly identical to the improvements made by a similar group of exercisers who pedaled for 1½ to 2 hours at a lesser intensity. Interval training is also the ticket for better health. Researchers in Norway reported that interval training was far more effective for reducing blood pressure, controlling blood sugar, and improving cholesterol than traditional one-speed workouts.

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33

Percent more calories you burn after doing back-to-back sets of two different exercises (supersets) compared with sets that let you rest between moves, according to the
Journal of Strength and Conditioning Research
.

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When you stop and think about how your body works, all of this seemingly counterintuitive science suddenly makes a lot of sense. Our bodies are built to adapt to the work we demand of them. When you get up and go out the door for a leisurely jog, you’re asking your slow-twitch (endurance) muscle fibers to wake up and get to work, but all those fast-twitch (speed and power) muscle fibers go largely untapped. Over time, many of the neurons that once served fast-twitch fibers will get rewired to serve their slower counterparts. Others will die off. Turning up the intensity of your workouts not only gives you firmer, more shapely muscles by tapping in to all those unused fibers (think Dara Torres), but also fast-tracks your fitness gains, says HIIT training researcher Martin Gibala, PhD, professor of kinesiology at McMaster University. “High-intensity exercise kind of shocks your system. Your body thinks, ‘She’s making me do some really hard work,’ so it increases your total exercise capacity—your ability to use oxygen and burn fat—in a fraction of the time than if you’d exercised less intensely,” he says. In fact, according to neuromuscular researcher Christopher Knight, PhD, of the University of Delaware, there’s an almost immediate effect when you tap into your fast-twitch fibers with strength training and/or high-speed intervals. “We’ve found that you can increase your fast-twitch firing rates after just 1 week of training,” he says.

That’s the genius of the Superfast Workout Plan. You combine 15-minute resistance-training workouts with 15-minute HIIT workouts to lose the most weight. Scientists already know that combining cardio and resistance training works faster and better than either alone. When Pennsylvania State University researchers put three groups of overweight people on a diet and then had them do cardio, resistance training and cardio, or no exercise at all, they found that though each group lost roughly 21 pounds, the lifters dropped 6 more pounds, or 40 percent more, of fat (which, remember, takes up more room than muscle and doesn’t look nearly as nice). That’s right, nearly every ounce they lost was in the form of fat, while the other two groups dropped precious metabolism-revving muscle as well. Now you get to reap all these rewards in a fraction of the time you ever thought possible.

But the 15-minute secret doesn’t just give you the shortest, most effective workout on the planet. You’ll also:

1.
Trade Fat for Muscle

Whether you want to be bikini ready or are just looking to boost a sagging bottom, 15 minutes is all it takes. Premiere strength-training researcher Wayne Westcott, PhD, CSCS, instructor in the exercise science department at Quincy College in Massachusetts, confirms that when you choose your exercises wisely, a handful of moves—just four in some cases—is all you need to change your body composition. “Navy research shows you can get tremendous overall improvement—losing 4 pounds of fat and adding 2 pounds of muscle in 8 weeks—by doing just four exercises that work every major muscle,” he says. The four moves are the squat, chest press, row, and abs curl. Do them during several rounds of a 15-minute workout for total body transformation.

2.
Burn More Calories

Even better, the calorie-burning benefits of even the shortest strength-training bout keep coming long after you’ve left the gym. In a study from Southern Illinois University, researchers found that when volunteers did just one set of nine exercises, or about 11 minutes of strength training, 3 days a week, they increased their resting metabolic rate (the calories burned when just hanging out) and fat burning enough to keep unwanted weight at bay. And then even more great things will happen.

3.
Stay Young

Unless you do something to stop it, your body loses about half a pound of muscle a year after age 20, says Tina Schmidt-McNulty, exercise specialist at Purdue University Calumet. That may sound nearly insignificant, but when you consider that muscle is your body’s biggest calorie burner—burning five times as many calories per pound as fat—it’s like “taking your foot off the gas pedal of your metabolism right as you enter adulthood,” explains McNulty. That metabolism meltdown can lead to a creeping weight gain of 1 to 2 pounds per year. Little wonder then that the average American woman loses a metabolism-stalling 15 pounds of muscle and adds 45 pounds of fat between the ages of 20 and 50.

4.
Fit Into Your Clothes

Even if the scale doesn’t take a wild downhill ride, that lean muscle tissue minus the fat will keep you in those skinny jeans forever. How’s that? Because 1 pound of fat takes up 20 percent more space on your body than 1 pound of muscle. Resistance training—just 15 minutes a shot—is all it takes to keep your youthful muscle (and figure) for life.

5.
Sleep Better

High-intensity exercise helps you sleep like a baby, which in turn helps you keep pounds at bay. Australian researchers recently reported that men and women who did total-body resistance training for 8 weeks enjoyed a 23 percent improvement in their sleep quality. Even better, they were able to fall asleep faster and slept longer than before they started working out. That’s important because poor sleep wrecks your waistline. In fact, Stanford University scientists have found that body weight rises proportionally as hours of sleep drop below 7½ a night, likely because sleep deprivation triggers the hunger hormone ghrelin and the fat-storage hormone cortisol.

6.
Get Stronger

Resistance training is second to none for building bones. Unfortunately, women build their peak bone mass in their teens and early twenties and then start a skeletal slide around 35, when bone thins at a rate of about 1 percent a year; it’s two to three times that following menopause. A study of 124 men and women published in the journal
Osteoporosis
recently reported that high-intensity exercise like that found in our superfast workouts increased bone density in high-risk spots like the spine, hips, and legs in just 40 weeks. By contrast, those doing low-intensity exercise actually lost bone mineral density over the same time.

7.
Become More Flexible

Flexibility is the first thing to go, as your muscles shorten over time. Left unchecked, you can lose a full 50 percent of your flexibility over adulthood, which means waving a long-distance good-bye to your toes…from your knees. Using those muscles through a full range of motion, like you will in these 15-minute workouts, will keep all your limbs limber. In a study published in the
International Journal of Sports Medicine,
scientists reported that men and women doing just three full-body workouts a week for 16 weeks increased their range of motion in their hips and shoulders and also improved their sit and reach test scores by 11 percent. You’ll find specific stretching and strengthening workouts for even greater flexible benefits in our workouts.

8.
Prevent Heart Attacks

Regular resistance training strengthens your most important muscle—the heart—and improves the health of your entire cardiovascular system. In a study published in the
Journal of Applied Physiology,
scientists reported that volunteers who strength trained just 3 days a week for 8 weeks lowered their systolic blood pressures (the top number) by an average of 9 points and their diastolic blood pressures (the bottom number) by an average of 8 points. That’s enough to slash your risk of stroke by 40 percent and bring down your risk of heart attack by 15 percent.

9.
Avoid Diabetes

Muscle is simply good medicine. A 2003 study from the University of Sydney, Australia reported that resistance training could improve insulin sensitivity, which means fewer blood sugar spikes and crashes as well as fewer of those binge-eating episodes low blood sugar can trigger. Research also shows that resistance training is particularly good for burning visceral fat, the kind deep in your belly that smothers your internal organs and raises your risk of metabolic syndrome. Even if you have diabetes, it’s not too late to benefit. Austrian scientists found that men and women with type 2 diabetes who started strength training were able to significantly lower their blood sugar levels and improve their conditions.

TIP:
Research shows that resistance training is particularly good for burning visceral fat, the kind deep in your belly that smothers your internal organs and raises your risk of metabolic syndrome, a precursorto type 2 diabetes.

10.
Prevent Cancer

Resistance training fends off cancer-causing free radicals, according to a study from the University of Florida. Researchers there found that people who did resistance-training workouts 3 days a week for 6 months had significantly less oxidative cell damage than their non-lifting peers. High-intensity exercise, like the kind found in our HIIT workouts, also has been shown to protect against breast cancer.

11.
Get Smarter

No dumb jocks, here. Canadian researchers found that a year of just once-weekly strength training boosted brain power among women volunteers by nearly 13 percent. Other research has reported that strength training improves short- and long-term memory, verbal reasoning, and attention span. Now that’s a mind–muscle connection!

12.
Stress Out Less

Survival of the fittest is especially true when it comes to handling stress. Scientists at A & M University discovered that the fittest people have significantly lower levels of stress hormones than their couch potato counterparts. Scientists at the Medical College of Georgia have also found that blood pressure levels return to normal faster after a stressful situation in people with more lean muscle tissue compared to those with less.

13.
Be Happier

Pushups may work as well as Paxil for improving your mood. Researchers from the University of Sydney recently reported that people who did strength training on a regular basis were far less likely to suffer symptoms of major depression. Short bouts of cardio may be equally powerful. Scientists from Bowling Green State University reported that as little as 10 minutes of cycling improved mood in 21 men and women, compared with a similar group who did nothing during that time.

14.
You’ll Have More Time

In the pages that follow, you’re going to find all the information you need to follow the Superfast 15-Minute Plan. And then you’re going to have hours (heck, days!) for everything else!

How to Start

So if 15-minute workouts are so great, why aren’t more people using them? Because you have to know how to put them all together to make them work for you. That’s why we set our minds to creating the most comprehensive guide possible to unleash the magic of the 15-minute secret. And even we were amazed at how the Superfast Fitness Plan can be adapted to every kind of exercise to meet every conceivable goal.

This plan is the most versatile you’ll find. You don’t need to be bench-pressing barbells or even stepping foot in a gym (unless you want). You’ll find dozens or workouts you can do right in your living room. You can swim, bike, jump rope, elliptical train, and even power walk for your superfast fat-burning workouts. You’ll even find workouts to help you perform better on the tennis court or in road races, if that happens to be your weekend passion. You’ll also find an entire chapter of workouts based on the most
popular workout equipment
(and even some household items), including the ever-popular kettlebell, stability ball, Bosu, and even paper plates!

Following the
schedule
that we provide, you’ll be choosing three strength-training workouts and one HIIT workout each week. You’ll find at least two versions of most strength training workouts because it’s important to switch up your exercises as often as possible to keep your results coming. “Your body adapts to meet the specific challenges you place on it,” says strength-training researcher Wayne Phillips, PhD, founding partner in the STRIVE Wellness Corporation. “If you constantly challenge it in different ways, it will continue adapting and you’ll be less likely to hit a plateau. You’re also less likely to get bored with your workouts.” That’s why we’ve included multiple workouts to surprise your muscles with new and different challenges.