Fit in the City: Natalie Portman's trainer - and a webcam

Ruby Warrington works out at homein New York in front of her laptop

PUBLISHED: 17:00 EST, 23 March 2013 | UPDATED: 17:00 EST, 23 March 2013

Fit in the City: Ruby Warrington works out from home

Its 11.20am and Natalie Portmans personal trainer, Mary Helen Bowers, is putting me through my paces at my apartment in Manhattans East Village.

Down on my mat, Im guided through a series of leg lifts to tone and hone my inner thighs similar to the kind of moves Mary had Natalie do to get in shape for her Oscar-winning role in Black Swan.

Its part of a workout that Mary Helen, a former dancer with the New York City Ballet, calls Ballet Beautiful which is also popular with her other high-profile clients, actresses Liv Tyler, Kirsten Dunst and Victorias Secret model Doutzen Kroes.

MY LAPTOP STUDIO

As the burn begins to kick in, I can hear groans from other women. No Im not hosting a class at home, I have logged on to Mary Helens website, balletbeautiful.com, and joined one of her classes via my laptop.

When we finish, Mary Helen leans into her webcam which gives me a full view of her airy space in New Yorks Soho where the live class is in session. How are you doing Ruby? she asks.

I give her a thumbs-up even though my leg feels as if its about to go into spasm.

Mary Helen has been training clients remotely since 2008, when she was working with Natalie.

She was amazing for my business, but at the same time it meant I travell! ed with her a lot, says Mary Helen. I didnt want to leave my other clients hanging, so I bought a laptop and started training people over Skype.

When she opened her studio, she developed the software to allow people to join her classes online, too. A subscription costs 185 per month or its 23 a class.

ON CAMERA

Bye-bye gym, hello convenience, says the home page on wello.co, another site offering digital workouts. Having launched last summer with remote, one-on-one personal training sessions, it began offering classes open to up to five people at a time last month.

Here, you can find anything from yoga to full-on boot camp sessions, and the following weekend, I try an hour-long cardio circuits class. Soon I get an email from Dorothy, the instructor, asking me and the other girls whove signed up if we have any equipment she can incorporate into our workout. It turns out we all own a set of dumbbells.

Ballet beautiful: A webcam class from the website so you can take your classes at home

In the end, one of the other girls drops out and so Sarah who is based in California and I get Dorothy to ourselves. Jumping around my living room with my dumbbells, my eyes on my computer screen where I can see Dorothy in one window and Sarah in another, is a bit like doing a workout DVD but better.

Left to my own devices, I might have been tempted to sit out some of the tougher moves, but with the camera on me I am too embarrassed to give up so I power on through.

By the end of the class, Ive got a proper sweat on just like if Id worked out at the gym. But for a fraction of the price. An individual class costs 6.50, while a one-on-one session with a personal trainer is between 25 and 130, depending on who you choose.

QUICK FIX FITNESS

An even bett! er deal c! an be found at another site called fitnessglo.com. For 8 a month you get unlimited access to hundreds of prerecorded workout videos, ranging in duration from ten to 45 minutes, and covering every kind of workout under the sun.

Its like having your own fitness DVD library, and while you dont get the benefit of personal instruction, it beats them all for convenience you really can log on wherever and whenever.

I try a 30-minute cardio athletic circuits class the perfect quick fitness fix on another deadline-heavy day.

All this doesnt even begin to mention the ease with which you can find fitness instruction by watching videos uploaded by trainers to YouTube.

So will I be handing in my gym membership and switching to digital workouts instead? Probably not. For me, you cant beat the energy you get in a live class, with the teacher yelling instructions over a pumping soundtrack and 20 other people going for it on all sides.

But on those days when times extra tight, I will log on.