He's been crowned Mr Universe and weighs a massive 107kg of pure muscle, while she has won the UK's strongest woman contest and flip a 300kg tyre and dead lift 165 kg.

But while you might imagine professional bodybuilder Barny Du Plessis, 41, and his fiance Josie Keck, 42, from Norfolk, existing on a diet of chicken breasts and egg whites to fuel their training, the couple have been entirely vegan for the past year.

Barny who was crowned Mr Universe in 2014 is the world's first professional vegan bodybuilder and is starring in a new ad campaign for the animal rights charity PETA to encourage others to adopt a plant based diet.

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Josie Keck, 42, (right) met professional bodybuilder Barny Du Plessis, 41, (left) at the gym where she worked and now the fitness fanatic couple who live in Norfolk both fuel their workouts with an entirely vegan diet

Barny weighs 107 kg and was crowned Mr Universe in 2014. He can dead lift a massive 300 kg

'We don't eat or wear any animal or animal-derived products whatsoever - no milk, eggs, honey, wool or silk,' Josie told FEMAIL. 'I've always been a great animal lover, with a great passion for helping them.

'When starting bodybuilding, I ate chicken and turkey as I was advised to eat lean protein, changing to fish near a show. I also ate egg whites. But I could barely stomach it – I think all along my body wanted to be vegan.

'But now, Barny and I can proudly say we have been vegan for almost a year. Our "veganaversary" is in April.

'I do believe that the journey to being a vegan was parallel with my spiritual development. Also that to be a true animal lover, you have to be vegan. Why eat what you love?'

The bodybuilder is starring in a new ad campaign for PETA the animal rights charity to encourage other sports stars to turn vegan

When training for competitions Barny eats up to 4,500 calories a day, while Josie consumes 2,200 of vegan food.

While preparing for a competition their typical diet consists of a wide variety of vegetables; fruit such as apples, bananas, dates and berries; grains such as basmati rice, quinoa and tapioca, pulses like chickpeas and brown and red lentils; as well as powders such as rice protein, hemp protein and vegan protein blend.

Barny explained: 'We are serious in our crusade to save the Earth, the animals, ourselves and our dignity as a species. Also, Josie's cooking is really tasty and amazing in variety. Better than any restaurant.'

When Josie was 30, she was working in London in a high-powered job in production engineering and earning good money, but she became unhappy because she was embarrassed by her weight

Josie, pictured when she was overweight (left) left her job and started learning about nutrition and fitness. She is now a bodybuilder. She has transformed her figure (right) after starting weight training for the first time at the age of 31

Josie used to be a size 24 before she started weightlifting and fell for Barny (left). Now she is one of the UK's strongest women and can dead lift 165 kg

Barny is on a mission to destroy the idea that eating meat is associated with manliness.

'We're destroying this myth and sticking it in the bin where it belongs,' he said.

'I'm living proof that you simply don't need to eat meat or animal products to make great gains, be strong, healthy, fit, and feeling mighty.

'There is no link between meat and manliness or fitness. Plant-based nutrition is superior in all its aspects and forms.'

The incredibly muscular couple start their day with black coffee and beetroot shots and eat five plant based meals a day

As she continued with her weight training to pursue her fitness goals, Josie had another incentive to continue with her workouts as she met professional bodybuilder Barny at the gym

Josie used to train with weights twice a day so she'd have a better chance of bumping into Barny at the gym

'I'm very outspoken about veganism on Twitter. "Vegan warriors" is a phrase we use much like "henchman for the animals", "defenders of the realm", "vegan muscle mafia", "Mother Nature's bodyguards" and "planet protectors".

'We're on a lifelong crusade to protect our planet and save the animals.

'I truly believe that the only way we can ever survive as a species on this planet is to adopt a gentler, healthier, less selfish approach to our existence and that means adopting a vegan lifestyle.

'"Vegan warriors" is a state of mind, an ethos, and a way of living. We're making a stand and fighting for the animals and the planet.'

Josie pictured with her fiance celebrating his Mr Universe win in 2014. Josie has come second in England in NABBA Ladies Trained Figure and 10th in the NAC Universe in Hamburg

The couple, modelling for a gangster themed photo shoot, believe that being vegan gives them an advantage in their training over meat eaters

Josie does abs or oblique work every day, plus two to three 30 to 45 minutes fat-burning cardio sessions a day on a bike, stepper or a stairmill to stay in shape

Barny and Josie are set to wed at the end of this month after 10 years together

Josie added: 'I think vegans have a distinct advantage over meat-eaters in fitness. This is due to the many health benefits that veganism provides.

'Eating vegan also means you’re exposed to an awesome array of nutrient-rich healthy foods, and you feel great knowing that you're helping the environment and animals.

'People in the fitness industry forget that one's mental health is vital for being physically healthy.'

The couple do train together, but Josie has female-specific exercises she needs to follow to sculpt her physique.

Popeye fan Barny refuels after a workout with vegan protein blend and supergreens

Lunch for the strongman is brown rice, lentils, salad, nutritional yeast, which he dines on again as an afternoon snack

For dinner Barny eats oats, vegan protein and mixed seeds and cacaco, sweetened with stevia

'We end up going to the gym together then getting on with our own thing,' she explained. 'I train in a different way with less rest than him. I also have to do more fat-burning cardio after weights than him.

'I do abs or oblique work every day, plus two to three times 30 to 45 minutes fat-burning cardio sessions a day on a bike, stepper or my favourite, a stairmill.

This is in addition to walking our dogs two times a day with a weighted rucksack on my back. You have to enjoy the training, and we do. We also know what specific training to do for the goals we need.'

Barny has been a bodybuilder since his late teens, but his fiancee has not always been superfit.

She says that her amazing body transformation is due in part to going to the gym in the hope of bumping into Barny.

Josie said it was love at first sight when she first saw Barny but it took him a while to realise she was interested

Barny is on a mission to bust the myth in bodybuilding that meat is associated with being manly. The bodybuilding champion describes himself as a 'vegan warrior' and says they only way to save the planet is to give up eating meat and using animal products

Barny's muscular physique caught Josie's eye when she first spotted him in the Bristol gym where she used to work

The fitness fanatic describes himself as a 'vegan warrior' who is on a mission to save animals and the planet

'I was working in London in a high-powered job in production engineering at the age of 30,' she recalled.

'I was earning good money for my age, but I was stuck in the rat race, and was very unhappy and obese.

'One morning, I woke up and just couldn't recognise myself. I was most definitely unhappy about being size 24.

'I think I actually went through a mini breakdown and decided it wasn't too late and enough was enough.

After the couple eventually got together, Josie said that their joint energy was 'amazing' and they spurred each other on in training

Although the couple go to the gym together they end up doing separate workouts specific to their needs. Barny does not need to do as much fat-burning cardio as his fiancee

The couple do not eat or wear any animal or animal-derived products whatsoever - no milk, eggs, honey, wool or silk

After 10 years together, the couple are tying the knot at the end of this month

'I was embarrassed by my weight and how disgusting I felt, so I started power walking outside with my dog.'

Josie started to learn more about nutrition and, as the weight began to drop off, she joined a gym and started training at 6:30am every weekday before work.

JOSIE AND BARNY'S DAILY DIET JOSIE Pre-workout: Black coffee and beetroot shot. Post-gym:Vegan protein with supergreens. Breakfast: Vegan protein with rice flakes and pumpkin seeds with carob. Lunch: 100g hummus with six crispbreads and salad. Snack: Big bowl of seasonal organic veg with nutritional yeast and sweet potato. Dinner: Vegan pancakes made with rice flour, chia seed, vegan protein. BARNY Pre-workout: Coffee with coconut oil, beetroot shot. Post-gym: Vegan protein with super greens. Raw date bar. Breakfast: Vegan protein with tapioca/ rice flakes/quinoa, seeds, cacao & stevia. Lunch: Brown rice, lentils, salad, nutritional yeast. Snack: Brown basmati rice, mixed lentils and veggies with nutritional yeast. Dinner: Oats, vegan protein and mixed seeds, cacaco and stevia. Advertisement

'I started weight training for the first time at 31. It became part of my life, and the journey progressed,' she recalled.

'I then decided to give up my amazing job, go travelling, get educated in fitness and nutrition. I moved to Bristol working for a big corporate health club in finance, as well as going to college.'

As she continued with her weight training to pursue her fitness goals, Josie had another incentive to continue with her workouts.

'I was working in a big corporate Health Club in Finance, and Barny trained there. Reception would ring me when he entered the building, and I would casually walk by and say "hi",' she explained.

'I trained with weights twice a day so I would have a better chance of bumping into Barny in the gym.

'For me, it was love at first sight. I knew that we were meant to be together. It took him a long time to clock it though as he's not the quickest off the mark.'

After the couple eventually got together, Josie said that their joint energy was 'amazing'.

'We both just got better and better, me helping him and him helping me pushing in the same direction together,' she said.

The couple's gym offered Strongman training - which involves lifting heavy and awkward objects - and Josie decided to give it a try, and loved it.

Josie, 42, first started strength training a decade ago. She fuels her workouts by eating foods such as nuts, fruits, seeds and vegetables and has shunned all animal products

Josie has come second in the Britain's Strongest Woman Competition and won the UK's Strongest Woman

The fitness champion said that the nutritional and health benefits of being vegan give her an edge over the competition

'I eventually came second in the Britain's Strongest Woman Competition and then won the UK's Strongest Woman a month or so after that,' Josie said.

'But I decided I wanted to be more girly and get in my bikini on stage. We learned as we went along what worked for me, what didn't, with Barny winning shows around the world and striving for the big, big Mr Universe win.

'A few years later, I came second in England in NABBA Ladies Trained Figure and then placed tenth in the NAC Universe in Hamburg. I have now been in 15 shows, getting better results.