Train Like You're Being Chased by a Doberman
The good news is that you don't have to spend hours, or even a half-hour, working out.
The "bad" news? You have no excuses not to work out. Thirty-second workouts are designed to elevate your heart rate, build your muscle capacity and keep you coming back for more. These very short, very intense workouts are part of a somewhat recent trend in fitness that focuses on circuit (or interval) training, in which you do different kinds of exercises in rapid succession.
What's special about the 30-second workout is that yes, it is very short. It can also be done anywhere -- in your home, your hotel room or outside. So you don't have to join a fancy gym, you don't necessarily need sexy gym clothes and you don't need a ton of time. All you need is a little sticktoitiveness.
"I'm very big on eliminating excuses from people's minds," says Donovan Green, a high-profile personal trainer in the New York City area. "You can't say that you don't have time for a 30-second movement."
The exercises vary, but jump squats, regular squats, push-ups, jumping jacks, burpies and heavy weights with a lot of repetition are common. "I have different programs for everyone," Green says. And "everyone" means clients ranging from a 6-year-old to an 84-year-old (who can now curl 40 pounds after having done the interval training).
The idea is to do various exercises back to back, for however long you can. Even three movements will eat up just a minute and a half of your time.
The key is where the Doberman comes in. "For workouts to be short, they have to be intense. That sense of being chased by a Doberman makes sense if it's only for 30 seconds," Green says. He adds that where running is concerned, sprints are ideal -- so if you see a hill, sprint it. This would be more beneficial than, say, running on a treadmill.
[Read: Is It Time to Fire Your Personal Trainer?]
The Science Behind Short Workouts
"When you exercise, the idea is to upset the body's status quo," says Chris Jordan, director of exercise physiology at the Johnson & Johnson Human Performance Institute in Orlando, Florida. Jordan developed a seven-minute workout comprised of 12 30- to 45-second movements.
Upsetting the body's status quo means elevating the heart rate to strengthen the heart, Jordan explains. It also means varying the muscle groups you're working: The workout he designed begins with a cardio-based, total body exercise like jumping jacks. Next, you work the lower body with moves such as squats and lunges. Then you move to upper-body moves such as push-ups and tricep dips on the back of a chair. Finally, you work your core with exercises such as abdominal crunches and side planks.
"That sequencing of opposite muscles groups makes it integral in nature. You can give your best effort to a leg exercise because you know the next one will not be a leg exercise," Jordan says.
The constant variation also protects your body against injury, Green adds, since you should never be tiring out your muscles or joints in such a short time span.
Another benefit to these short, intense workouts takes place on a cellular level, Jordan explains. High-intensity workouts increase the number of mitochondria inside cells, which is where energy is stored. So by doing this type of workout, you not only make your heart stronger; you increase your own capacity for aerobic activity. And this ultimately has a protective benefit, for example, in preventing diabetes because having more mitochondria improves your cells' ability to absorb glucose, which is locked out of the cells in diabetes.
[Read: Energy Management: Taking a Page From the Military Training Book.]
The Perfect On-the-Road Workout
Perhaps the best thing about the workout is the fact that it's convenient. Jordan developed it for "corporate athletes" -- business executives who spend a lot of time on the road and claim to have little time to work out. So Jordan developed a workout that wouldn't even require people to go to the hotel gym. "The hotel room workout requires nothing more than what you can find in a hotel room," he says.
The only equipment necessary is a chair for tricep dips or chair steps. Apart from regular travelers, busy professionals and parents can adopt the workout, Jordan says. "Who hasn't got seven minutes when they get home from work to do a workout like this?"
Jordan also created an app called the "Johnson & Johnson Official Seven-Minute Workout," with more than 800,000 downloads. It has 36 different exercises because Jordan wanted to provide options for everyone, from his own 76-year-old mother to his triathlete brother. Jordan recommends that if people repeat the seven-minute sequence, they do so no more than three times consecutively. And if they do that -- the workout times three -- they should not do it more than three times a week.
Whoever you are and wherever you are, the same rules apply for doing 30-second workouts, Green says: Don't work out on a full stomach or if you have achy joints. Be well-rested. And perhaps most importantly, because time is (literally) of the essence, "Get a timer and just go for it," he says.
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Kristine Crane is a Patient Advice reporter at U.S. News. You can follow her on Twitter, connect with her on LinkedIn or email her at kcrane@usnews.com.
