Caroline Pearce, former international heptathlete
Caroline, 34, is a sports presenter and the go-to fitness model for the likes of Nike and Adidas. How does she define those killer abs?
'Ditch crunches! Instead, burn belly fat with high-intensity workouts and squats – they force you to activate your core. Avoid sugar and alcohol. Sugar makes your body hold on to fat. Alcohol is loaded with it. Wear a belt when you eat. It makes you aware when you’re getting full.
'I eat every two to three hours; breakfast is three egg whites and one whole egg scrambled, with ham, flaxseeds and berries. Lunch is turkey with lots of colourful vegetables and my evening meal might be fish with green veg and beetroot. I snack on nuts and frozen dates (which taste like toffee).
‘Two days before a shoot, I avoid any foods that could lead to water retention – so no salt or processed foods and lots of asparagus, a diuretic.
‘I work out six days a week. I’m a big fan of PowerPlate, plus I do two weights circuits, an interval session and lots of core strength work. I don’t spend hours in the gym, instead I work really hard for 30 minutes, making every rep count.'
Madonna's backing dancer Sofia Boutella, star of StreetDance 2
Madonna's go-to dancer Sofia Boutella hit the big screen in the film StreetDance 2. How does she stay in shape?
'I learned discipline from Madonna. She works out for two hours a day. When I danced on her Confessions and Sticky & Sweet tours, she taught me to start every day with a workout and I still do.
'I run, I do resistance workouts and 80s-style aerobics workouts that focus on my legs.'
Sofia adds, 'I believe whatever you give your body, it will give back to you. I eat healthily, so that's the constant. If I go out with a friend, I'll have a drink but I won't get wasted.'
Katie Biddulph, founder of sports clothing brand StridersEdge
Katie Biddulph, 28, started StridersEdge to produce performance-focused, female-specific clothing for hiking, running and fitness. How does she fit exercise into her life?
'I make time to run every day. By late afternoon, my body feels like it's craving a run. With my own business, I could easily let work consume me and never move from my laptop, but I'm running a sports brand so it's important to remember where it all started - with my love of adventure and the outdoors.'
She adds, 'I start every day with a vegetable juice. I alternate between apple, celery and lemon, and beetroot, tomato, carrot and ginger. The colours are amazing. I feel like I'm drinking the elixir of life!'
TV presenter Helen Skelton
Blue Peter presenter Helen Skelton has kayaked solo down the Amazon, ridden a bike to the South Pole, run the Namibian ultra marathon and walked between the chimneys of Battersea Power Station on a tightrope. How does she do it?
Helen says, 'I live by the principle you've got two choices in life: worry, or get on with it. As soon as you acknowledge bad things, they get worse. People say I'm fearless, but I'm not at all - I'm just naive, so I give things a go.
'My body is a symbol of my achievements. It's totally changed since I joined Blue Peter. I'm a stone heavier, but my body image is diferent. I couldn't have kayaked for 16 hours a day down the Amazon if I was size six.'
And what about training? 'Zumba classes prepared me for the South Pole. My teammates made fun of me, but it really helped. In fact, I tried every class going at the gym. Sir Ranulph Fiennes may not do it that way, but at least I never got bored.'
Keeley Dann, dancer
Keeley, 26, has toured with Rihanna, danced on The X Factor and performed in the Olympic closing ceremony. What keeps Keeley energised?
'Eating a big breakfast fuels me for the day. It’s usually yogurt with berries and seeds, and toast. Then chicken salad at lunch and fish and veg for dinner. I snack on foods that are easy to digest, like breakfast biscuits, pistachios and bananas.
'People assume dancers get fit on the job, but I do BodyPump and Pilates, as well as jazz, funk and hip-hop classes. I have to be careful about what I eat, so I’ll stick to lean protein and vegetables as much as possible, plus nuts and bananas for snacks. I eat pizza and have a drink on a Friday night but I can’t work when I’m hungover, so I don’t overindulge.
'I get regular massages to stop my muscles getting tight and I visit LA to keep up with all the new dance styles.'
Zara Phythian, 27, stuntwoman, actress and kickboxer.
Zara was the first Brit to be inducted into the International Karate & Kickboxing Hall of Fame. How does she get her kicks?
'I work hard to get into the best shape I can before I walk on set, so as well as teaching five classes a day at my martial arts school, I run four miles a day, use free weights four times a week, and see a PT three times a week. When I’m preparing for a very physical role, I’ll do more cardio and if I need to look really toned, I’ll ramp up the protein to develop muscle tone.
‘My diet is super-healthy. I’ll have porridge with bran for breakfast, chicken and salad for lunch and dinner, plus The Total Package (TTP) energy drinks.
'Because you’re using every muscle, you get an all-over workout in a class like kickboxing. The high energy workouts in classes like Taekwondo give you an adrenaline buzz, and hitting pads in Thai boxing is one of the best ways to de-stress. Martial arts leave you confident you can handle yourself. I’d recommend Capoeira, which has elements of dance, or judo.'
Davina McCall, TV presenter
She's been bouncing round our TV screens for 15 years and has found her way into our hearts thanks to the sense that she's 'one of us'. A former drug abuser, Davina McCall is refreshingly honest about her less-than-perfect past. And she manages in her early forties to look as slim, toned and fabulous as she did back in the late 90s when she hosted Streetmate.
Her secret? 'I've always done workout DVDs - I loved the Cindy Crawford one - but I never in my wildest dreams thought I'd make one of my own.'
Lucky she did - the Davina McCall fitness DVDs have sold more than 1.3 million copies worldwide, and Davina still does them herself to keep in shape.
Davina says, 'I started training with Jackie and Mark [Wren, her husband-and-wife personal training team], and the results were so brilliant I thought - I've got to share this!'
She adds, 'Body Buff is my favourite because it's got the best abs section and I love a bit of ab toning.
'None of us is perfect, but I'm always striving to make myself a bit better. I'm a work in progress but I'm definitely working on it. And if I can, anyone can.'