Marissa Montgomery finds out how Jessica Alba gets those perfectly toned abs with the hottest, sweatiest dance class in New York

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I’m not much of an action/superhero movie fan, but when I saw Sin City the one thing I remember thinking was: ‘Wow, look at Jessica Alba’s amazing abs’.

Fast forward to a few weeks ago when I was invited to take a dance class with the lady who is partly responsible for Alba’s Abs. I was invited to join a one-off dance class with Jennifer Johnson who was teaching at New York’s famous dance school, Alvin Ailey.

I usually like to stay away from dance classes. Although I love to dance I’ve always found it a challenge to follow a routine. It’s never my main choice of workout as I’m usually trying to concentrate so hard on getting the steps right that my technique suffers.

However with summer on my doorstep and Jennifer fresh off choreographing Alba’s dance routines in Sin City 2 I felt I should grab my chance to dance. After all, when she’s not training Alba for her new movie (she’s currently filming ‘Dear Eleanor’, where   is said to request Johnson on set), she can be found on tour with the likes of Beyonce or Kanye West or simply teaching at her Hollywood studio.

I arrived at 8am at the Alvin Ailey studio and was greeted by Jennifer, clad in an all pink workout outfit and big smiles. We started by learning the routine and following her as she showed us lots of ‘JJ Dancer’ signature moves.

This powerhouse workout, known as the JJ Dancer Technique, was devised by Johnson - combining her years of study of all types of dance. It brings intense body conditioning, plyometrics and kickboxing all together into one hot sweaty dance party.

It’s really a total body conditioning class using light hand weights, resistance bands, gliders (these are brilliant and worth investing in - fabric discs that you use under your toes when planking, which means you can work out on any wooden floor). She also uses ballet barre, and mat work. The class is a combo of hip–hop, salsa and ballet, and of course rather embarrassing booty shaking.

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It was a serious challenge and at times I thought I was going to pass out from the pace of it. However, Jennifer is kind and encouraging and is constantly switching it up so everyone can follow. The class gave me a new-founded respect for Britney Spears and all those people on Strictly Come Dancing. I will never laugh at the TV again!

After class everyone was rehydrating with a new fitness drink, Reboot. It’s an antioxidant drink, rich in vitamin C and herbal supplements. The aim is to combat ‘oxidative stress’, so I was told if I drank this magic concoction I would feel better, and have less pain from the workout the next day.

The packaging is interesting in itself; it’s a little plastic pouch, with half containing liquid and half the special powder. You twist the bag to mix and shake, then drink immediately. It’s not totally untasty. It’s like watered down prune juice. I actually ended up drinking it after I went to the beach and had too much sun as well, and felt it helped. As promised I also wasn’t aching the next day; I’m not sure if this is the drink or the fact I faked a few of the moves...

While Rebooting, I caught a few minutes with Jennifer and asked her for some insider tips.

When training someone for a movie, how far in advance before shooting do you start work?

“It depends on the project and how long the client gets to prep. I typically start as soon as they find out that they will be working on the film. It’s best when we have at least a month.”

Jessica Alba has the best abs - can you talk me through some of your favourite workout tips you use when working with her?

“Jessica is a great dancer and her body looks amazing when we do a lot of dancing in her sessions! Dance cardio is a great way to hit the abs from different perspectives and it tones the entire body in a totally different way to other workouts. We use dance cardio, floor gliders and a wide variety of crunches in a specific sequence to target her already banging abs. The secret is to include dance cardio with the body conditioning… and the dancing makes the workout so much more fun too!”

How many hours a week do you train with Jessica on average to see results?

"When training for a film, I typically see Jessica about six hours a week."

How many hours a week do you believe you should exercise to see results?

“Everybody is different, but the one thing that remains the same is, the harder you work, the more results you’re going to get… point blank! I like to work with my clients to build the stamina to train for 90 to 120 minutes. I would love it if the world could all get some form of exercise in at least one to 1.5 hours a day, five times a week, but this may not be possible for everyone. If that’s the case, on a day that you are unable to workout, why not opt to ride a bike to work or walk to the grocery store? The good news is, overworking your body isn’t the key to a perfect bod either. So make sure that you give your body adequate recovery time and plenty of sleep!”

You are Raw Vegan - can you tell me why you made this decision and how you keep your energy levels up when you are working out so hard?

“I became vegetarian in the year 2000 purely because of my love for animals. Consequently, the effects that ditching the whole carnivore lifestyle had on my body were amazing!  I immediately shed extra pounds and felt so much healthier. About six years ago, I was doing a raw cleanse and found that my body looked and felt even better in the absence of cheese, dairy, and eggs. From that day forth, I decided not to eat anything that came from an animal at all.

"Actually, I truly believe that the only way I am able to keep my energy levels up so high is because I’m vegan. I eat live foods, and now I feel so alive. Seriously… my energy is off the charts! As a raw vegan my body doesn’t have to stop what it’s doing to digest food and no animal has to die or work to feed me. I know the animals are pretty excited about that, because I can eat like a cow!”

Are there any quick tips you can share with us on shaping up?

“Well, this one is easy! Exercise regularly. Drink plenty of water. Eat organic, live foods. Get seven or eight hours of sleep nightly. And here’s the one I hate…BACK AWAY FROM THE COOKIE JAR! Sorry, I had to yell it. That last one was for me too.”

What’s your go to dance song?

“That’s a hard one! I have SO many dance jams. I’ll give you my top two all time dance cardio jams: “Wile Out” – DJ Zinc Feat. Ms. Dynamite and “Jerk it” - Thunderheist.”

How important is stretching?

“It’s important to stay flexible and stretching does just that, plus increases range of motion, gives you more energy, and may be helpful in preventing injuries. In addition, proper stretching techniques can help you reduce the amount of tension in your muscles and help you to become more relaxed overall, both in the body and in the mind. If you can find it in your schedule to stretch for at least 15-30 minutes each day (after warming up, of course) you can reap the many benefits that stretching has to offer.”

You use a mixture of lightweights in your class - what weight do you recommend and why?

“I recommend 3lbs for working the arms, performing high reps. No more than that is necessary to get beautifully sculpted, feminine arms. I also love to dance and kick box with the dumbbells, in which case I drop down to 2lbs. When I use the weighted bars to work the body as a whole, I like to use 9lbs or 12lbs.