Celebrities like Katherine Heigl are praising Australian fitness star Kayla Itsines' regimen for whipping them into incredible shape -- here's how it works

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  • Actress Katherine Heigl credits a program called BBG developed by Australian fitness star Kayla Itsines with helping her get back into shape after having a baby.
  • The program, designed by personal trainer Kayla Itsines, is based around a science-backed workout regimen called high-intensity interval training, or HIIT.
  • I tried one such program recently and was blown away by its effectiveness.

Do you have seven minutes? You could spend them getting into shape.

It may sound like hype, but working your body fast and hard for just a few minutes – interspersed with short periods of rest – is an effective means of toning your muscles and improving your heart health.

This type of exercise goes by a handful of names, including high-intensity interval training, HIIT, and tabata, but the gist is the same. The science-backed program boils down the strength and heart benefits of a sweaty bike ride or a trip to the gym into a concentrated aerobic workout that you can do at home.

This interval approach has recently spawned a handful of apps and routines, one of which is personal trainer Kayla Itsines’ Bikini Body Guide, or BBG. Actress Katherine Heigl credits the regimen – which can be followed via Itsines’ app, Sweat With Kayla – with helping her reincorporate exercise into her life after giving birth in December 2016.

“I won’t lie, the workouts are real a– kickers,” Heigl wrote in an Instagram post this week, “but the progress I’ve made in only five short weeks has kept me motivated and inspired to keep going.”

It’s been almost 14 months since Joshua Jr was born and it has taken me about that long to really get back in shape. The first pic was taken one month after he was born. The second pic was taken almost a full year later and the last pic was taken this weekend. I wish I had a few from in between the first and second so you could really see how slow my progress was but alas…I was busy covering it all up those months, not posing in my unders! Anyway, I have a beach vacation coming up, a new job I start filming in April and my deep desire to feel fit, strong and sexy propelling me forward the last two months to finally loose the last of my baby weight and do a deep dive search for the ab muscles I knew were buried under that belly somewhere! I was wholly and totally inspired by Miss @rachparcell and the before and after pics she shared after taking the #bbg challenge. I had never heard of it but she looked so damn great (she had her baby just a few months before me) that I had to check it out. I found a fantastic app called #sweat that features several different #bbg programs you can choose from and makes it incredibly easy to do anywhere, which for me means in my bedroom at home! I won’t lie, the workouts are real ass kickers but the progress I’ve made in only 5 short weeks has kept me motivated and inspired to keep going! I am so grateful I’ve had a full year to find those ab muscles and get my butt back up where it belongs and wasn’t forced by work to snap back into shape but it is time to make the strength, fitness and overall health of my body a priority and I am so grateful that @rachparcell shared her story and got this mama motivated!

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Interval training will make you sweat

When I heard about interval training, I was hesitant to believe that the health benefits of a two-hour bike ride could be condensed into a few minutes of squats and lunges. But I decided to give the Johnson & Johnson Official 7 Minute Workout – designed by exercise physiologist Chris Jordan – a try after speaking with him in 2016.

“High-intensity interval training can provide similar or greater benefits in less time than traditional longer, moderate-intensity workouts,” Jordan, the director of exercise physiology at the Johnson & Johnson Human Performance Institute, told Business Insider.

Jordan’s workout is available in a free app and gives users 72 exercises to follow, like jumping jacks, sit-ups, and push-ups. Ten require nothing but your body, and for the others you just need a chair that can support your weight. The latest version of the app lets you do each exercise along with Jordan.

SquatsShutterstock

Kayla Itsines’ workouts are based on the same idea. She also runs a blog and corresponding app – people can sign up for her 12-week program, which includes three 28-minute workouts per week, plus health and nutrition advice, for $US20 a month.

Itsines breaks each fitness routine into a region or muscle group – sometimes she focuses on arms and abs, other times she targets legs. Like any interval-training plan, it involves a variety of moves such as planks, push-ups, jumping jacks, and squats. During these short bursts, you push yourself at your maximum capacity.

Then, after each sweaty interval, you rest to catch your breath before quickly moving on to the next exercise. At the end of the workout (which could be as short as seven minutes or as long as 28), your whole body should feel it.

If you’re not into gyms or fitness classes, interval training might be a good fit for you

Some studies suggest that interval training may be as good or better than regular endurance exercise for building muscle and protecting the heart.

For one thing, the program may be easier to embrace since it involves no equipment or pricey gym fees, and even people who aren’t used to working out can give it a shot. A 2011 study published in the journal Medicine and Science in Sports and Exercise looked at the effect of interval training on previously sedentary adults. They found that the regimen significantly improved the participants’ muscle health, suggesting it was a practical fitness intervention for people who don’t typically exercise.

Interval training’s combination of cardio and strength training also appears to provide a handful of benefits for the body that are on par with those you’d get from a traditional workout. Areview of studies published in the International Journal of Cardiology in 2013 looked at nearly 500 people with chronic heart failure, and found that interval training was linked with better results than plain old endurance exercise when comes to a key measure of heart health.

Whichever workout you decide to try, the most important thing is that you enjoy it enough to stick with it. While Itsines’ program lasts 12 weeks, that’s likely meant only as a jumping-off point. To get lasting benefits for your brain and body, experts recommend maintaining a regular fitness regimen for life.

“To achieve results, consistency is key,” Jordan said.

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