When keen runner Julie Creffield was training for a marathon when she was a size 18, she was often heckled with taunts of 'Oi, fatty!' as she ran. Even her doctor told her she was too big to contemplate running 26.2 miles and should give up on her goal. With stories like this, it is perhaps no surprise that a new survey has found two thirds of women believe they can't run - despite being desperate to be fitter and healthier. Scroll down for video . When she was a size 18, Julie was told she was too fat to run but she completed a marathon, left, and has done numerous races since, including one at the London 2012 Olympic park, right . Julie, 37, from Stratford in East London, didn't let her critics stop her from running. She completed a marathon in 2012 - and has done numerous other races since. Now through her website, The Fat Girl's Guide To Running, she's encouraging other women to take up the sport regardless of their size and ability. She appeared on today's This Morning with sub-three hour marathoner Nell McAndrew to launch the ITV show's Run For Your Life campaign. Julie said: 'Two million more men than women in the UK play sport because women are often too worried about what they look like and fear they will be judged by others, this has to stop. 'Run For Your Life will show that anyone can find success with running, and show that women of all shapes and sizes that running can be fun and can be a great way of improving physical and mental health. And if enough women get involved and give it a go, we can really start tackling negative perceptions in our own communities. 'I was told by a doctor I was too fat to run, and just three weeks later I proved him wrong by running the Brighton Marathon, but you don't have to be able to run far or even fast to benefit from the joys of running, its all about taking part and being inspired…even if you are still a little bit rubbish at it.' Julie, back right, appeared on today's This Morning with Nell McAndrew, back left, to encourage women to take up running. Front row from left: Francesca, Kerrie and Shirley are taking up the challenge . Marathon runner Nell McAndrew encouraged the women to believe in themselves . Nell, whose Guide To Running book was published by Bloomsbury this month, added: 'Break down that barrier of being embarrassed and you will meet like-minded people in the running community. 'There's lots of support on Twitter with groups such as UK Run Chat. 'When you start running, your confidence will soon grow. I just used to go to local park and could only manage short distances but I gradually built it up. Doing races is real confidence booster so believe in yourself as you can do it.' A This Morning poll of 1000 women found that 60 per cent think they can't run yet 88 per cent would like to be fitter than they are. Seventy per cent haven't been for a run in the last year but more than 75 per cent plan on getting fitter this year. Many women are put off running because they fear they are not fit enough and are self-conscious about being seen sweating and panting while out on a jog. Julie loves running and has never let her size hold her back. She encourages other women to do the same . Others believe their size is holding them back so they don't bother - even though by taking up the sport they could lose weight. The This Morning project, like the recently launched 'This Girl Can' Sport England campaign, aims to show women they can run - even if they are currently unfit and overweight. The show will follow three novice runners - Shirley Hargan-Kennedy, 38, from Glasgow, Francesca Kennedy, 23, from Redditch, and Kerrie Jones, 37, from Cannock, Staffs - as they train for five weeks to run 5K. The show is encouraging viewers to join them on the journey by taking up running themselves. The three women revealed they currently fall into the camp of not believing they can run but want to give it a go to improve their health and wellbeing. Phillip Schofield hands out new trainers to the three woman sat on the sofa who believe they can't run but have agreed to try a five week programme culminating in a 5k race . Francesca said: 'I've tried running up and down my close and I feel like I'm going to have a heart attack.' Shirley said she wants to become like the runners she sees out training enjoying the exercise and taking in the scenic countryside when they run off-road. Overweight Kerry explained that her motivation is to partly aid weightloss, as well as to set a good example to her children. She said: 'I know I have always been fat but finding out I'm now classed as clinically obese is scary. 'I need to do this for my children, it's not about dress size anymore it's about health. Society is more accepting of big woman now but for health that's not good. 'What I hope to get from this is a new me so I'm not the fat mum at the school gates.' Julie knows how Kerry feels as she weighed 20st when she first started running in 2003. Now she is slimmer and fitter but she explains women have so much more to gain from taking up running than just weightloss. Nell looked the part as she arrived at the ITV studios in her running leggings and trainers . She said: 'I'm not a size 8 and if I can do it, so can you. Woman who take up running will come to realise it's fun and then they will want to do it more. We often hate running as it hurts but you can find ways to enjoy it. 'You have to build up gradually stop letting excuses like having bad knees or a bad back or no sports bra stopping you getting out the door. Get out and start walking then build up to running and you will see the health improvements.' Julia advised anyone who is concerned about taking up running to speak to their doctor first. To avoid injury, she also recommends wearing supportive trainers, starting slowly and stretching after running. One of the reasons many people avoid running is a fear that it's bad for their knees. But a study of 75,000 runners, which was published in Medicine & Science in Sports & Exercise last year, found that 'running significantly reduced osteoarthritis and hip replacement risk due to, in part, running's association with lower BMI (Body Mass Index)'. Nell McAndrew finishing the 2012 London Marathon . 1. Invest in a good pair of trainers and some seam-free running socks. You are best going to a specialist shop for this as they will assess your running gait (or style) to find the appropriate pair. It's the only big investment you have to make and it's so important that your feet are comfortable. 2. Buy a good sports bra. Aside from running shoes, this is the other essential for women. 3. Team up with a friend so that you can support and motivate each other. If you have arranged to meet someone you'll be less likely to back out. Running with someone else also helps the minutes tick by as you have a good gossip. Alternatively look for a beginner's group or couch to 5km scheme in your area (runengland.org is a great place to start). 4. Make steady progress. If you haven't run before, download a couch to 5km programme or app (there are plenty available for free) as they advocate lots of walking and running to start with. Build up gradually, increasing your running duration by no more than 10 per cent every week. 5. Have a plan. We women are all so busy and I find it helps to sit down at the start of the week and think about what I have on each day so that I can plan when to fit in a run. It's amazing how it slots into your routine - I've jogged to school to pick up my son with my daughter in the pushchair and then jogged back as he scoots or cycles along with us. Make it work for you. 6. Log your progress. Psychologists have proven that keeping a record of your running achievements helps to spur you on. So write everything down in a diary and flick back through it when you need a boost. 7. Enter a race. OK, this is not as daunting as it sounds, I recommend everyone tries a parkrun (parkrun.org.uk) after about 5-6 weeks of running regularly. These free 5km events are held weekly at around 300 parks in the UK. 8. Be competitive. This doesn't mean you are aiming to win Olympic medals or set a record for your age group. But making targets for yourself can keep you going. It might be that you set a goal of running 5km after 6 weeks or finishing ahead of a certain person in training. It all helps hugely with motivation. 9. Eat well. One of the things I love about running regularly is that I can stay in shape without having to stick to a strict diet that forbids the eating of certain food groups. In my modelling days, the girls who were on no-carb, or no-fat diets always seemed so miserable. And sports scientists all agree that a moderate amount of carbs are essential for running. 10. Remember why you run. Maybe it's to lose weight, to raise money for charity or to de-stress. Whatever the reason, don't lose sight of it. That way when that little voice inside your head tries to stop you from heading out on a run to stay on the sofa with chocolate instead, you will overcome it. Running will empower you in a million ways. Run first and eat your chocolate afterwards (chocolate milk is proven to be a great recovery drink). This Morning's Run For Your Life campaign starts today at 10.30am on ITV. Visit www.itv.com/thismorning for more details.
Julie Creffield was told she was 'too fat to run' when she was a size 18 .
But she still completed a marathon .
Now encouraging other women to run whatever their size .
Launched This Morning's Run For Your Life campaign with Nell McAndrew .
Poll carried out by show found two thirds of women think they can't run .