For her latest book the PT and global fitness phenomenon asked 40,000 women about the body confidence issues standing in the way of their fitness goals. Here she tells Victoria Woodhall about hers

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GTG: You surveyed thousands of women across the globe about body issues and motivation. What did you find?

Kayla: “We asked women things like, ‘how many of you have felt insecure at any time and because of that insecurity do you work out or not? What are your main concerns about your body?' We got those results and wrote the book ( The Bikini Body Motivation & Habits Guide)  accordingly. We do most things based on what our community feels. It was really informative; 98 per cent of women are insecure, if you read the stats. Whatever insecurity that we do have, 56 per cent of us don’t work out because of it. That’s nearly 60 per cent of us going, ‘I don’t like my this or that, so I’m just not going to do anything about it’. For us, that was huge.”

Were you surprised to find that so many women lacked motivation?

“I think I already knew, as I have trained women and have been doing this since 2009, so that’s almost ten years of realising that we have this fluctuating sense of motivation throughout the year. It can be really random, sometimes you can feel super-motivated and then it just slowly tails off. I see that within myself so it was only natural to write a book that showcases that and how we can get around that drop.”

In the survey, you asked a handful of key questions. How would you answer the same questions yourself? The BBG survey says: 98 per cent of women felt insecure at some point. Do you feel insecure?

“My insecurity is my hair. I don’t have great hair and I have a history of female pattern baldness in my family. But I deal with it and work out ways around it. Today I’m wearing a bun. I have hair ponytails that make me feel more confident.

“I also talk about it [online] - a lot of people can relate to it. I have always had really thin hair even as a kid. I watched my mum’s hair slowly fall out and my grandma’s. It makes me a little bit upset when I have got to go events or if I’m doing a media shoot and they say ‘we want to do two looks, we want your hair up and we want your hair down’. I don’t do down! I just work my around it and say this is what’s getting me down because as women, we don’t want to talk about our insecurities, but once we do we normalise it.”

Your survey showed that fewer than a third of women are happy with their bodies. Are you happy with your body?

“Now I am. People always try to tell me to change – you need to squat more or to have bigger arms. Once you know your body and what it can do, you just laugh. I say to people ‘you are welcome to come to the gym with me and spend 30 minutes working out and see if you still say what you say afterwards’.

“I have never really looked at my body and hated it but I remember a time when I finished school, when I felt like I needed to get fitter, I needed to get stronger – for myself. I was playing basketball but I wasn’t really strong like I am now. Now I am able to do chin-ups and weight training and that made me feel really confident. I am in a really good position and I’m really happy.”

Are you happy with your body because it has changed or because your attitude had changed?

“I think my mindset has changed. There are always days when women get up and we don’t like our stomach or we feel really bloated because we are getting our period. Right now, I have my period but I know that no one is really looking at my stomach in the way I’m looking at it. Everyone is looking at me actually [online] but I know they are focusing on what I’m saying."

Your survey asked women whether they were more concerned about their face, the shape of your body or their size. 85 per cent of women said size. What are you most concerned about?

“I am not concerned about anything! When I was younger, I had quite bad skin and was really self-conscious about it. I used to pull my school jumper up over my mouth to hide it. A good skincare routine sorted it out – drinking more water, double cleansing amd using a moisturiser - I never used to use moisturiser because they had oil in them. I was putting makeup on and wasn’t exfoliating at all. It all changed when I got into a good routine and good habits.”

Your survey said that insecurity demotivated nearly half of all women Do you feel demotivated?

“Yes, when I have my period, I wake up not wanting to work out. On those days if I’m in pain I just rest and do something more productive somewhere else in my life so I’ll do emails so I  don’t get to the end of the day and feel I’ve done nothing. I plan for that feeling of demotivation. When I get my period, I’ll plan to eat that [unhealthy] food, and not feel guilty. I’ll even buy it a week in advance. But the next day if I feel good, I know I’m going to go for a walk and then the next day I’m going to work out. Same for birthdays [when you know you’re going to eat cake] – plan. When I’m exercising the next day, I’ll feel good because I’ve planned for it.

“I put all my plans in my phone. I even put silly things in and I make everything one hour. I don’t put 15 minutes here or there because then you are chasing your tail all day when you are running late, so everything goes for one hour. If it doesn’t fit into that one-hour schedule it goes into another day.”

56 per cent of women said they choose not to train because of how they felt about their bodies. Have you ever chosen not to train because of an insecurity?

“No, because when I am feeling demotivated, discipline kicks in. Once you are disciplined you don’t need motivation any more.  Motivation fluctuates but discipline is automatic. Take brushing your teeth for example, you are not motivated to do that every day, you are disciplined.  Now, if I miss a week of workouts I feel odd and out of my routine."

The formula for motivation in your book is 'value x expectancy = motivation'. How did you come up with it?

“There’s is so much research behind it. We wanted to find an easy way to understand motivation, that works for our community. In the fitness industry we over complicate things. Once you have those two numbers – how much do I value what I’m doing and how likely am I to succeed, then you can work out how long it is going to take you to turn that motivation into discipline.

“We look at simple things like bad habits and what triggers them and how can I get around them. It’s not that hard and that’s what women have been telling me at book signings.”

What has been your toughest habit to break and what has helped?

“Probably the period eating thing. That was one of my worst habits - you don’t know what to do with yourself. I’m not a lucky person who doesn’t feel anything when I have my period. It’s not so much over-eating but choosing the wrong foods and not having nutritious meals that I know will make me feel better - I just can’t look at them. I will look at a bowl and salad and – bleurgh! It’s weird how your body works at that time. I’ll get a stomach ache and have to have a heat bag on my stomach and I have to lie down in bed and then I get a migraine - my sister is like that, my mum too.

“Scheduling has helped me. I know that I’m not going to get up at 6am and have my walk and that I’m going to be bloated and have a stomach ache. I give myself three days. I’m really honest with my followers as well – I’ll tell them I’m out for three days. As soon as I take that first walk I’m completely normal again. I have an period tracker app on my phone called Flo  where you can track your symptoms. I go on to Flo when I feel sick and it says ‘period in two days’ and I go ‘a-ha!’.”

“Another bad habit is being on my phone all the time. Because I run my own Instagram page, I need to learn to switch off, but I have it in my hand all the time. My mum will be talking to me and I’ll be looking at my phone, aimlessly scrolling and she’ll look so furious. I just need to stop doing that.”

And the beauty product you wouldn’t live without?

“My skin is constantly exposed to air conditioning at home and when I’m flying, so I get through loads of hydrating serums. My boyfriend Tobi sleeps with the fan and the air conditioning on every night. I have to sleep with the covers over my head! My current favourites are B-Hydra Intensive Hydration Gel by Drunk Elephant,  £82.98 and O Cosmedics O-Biotics B3 Plus  ($119.00 AUS)."

Kayla's new book T he Bikini Body Motivation & Habits Guide is published by Bluebird RRP £16.99, currently £7.99 on  . Read our  review here .