When you're challenged to the extreme, you learn so much about yourself. And when you're willing to give that ultimate sacrifice, when you're willing to tackle a job or a task or a mission head-on and give 100%, you can achieve amazing things because you're almost fearless.

I'm 5' 8,'' and my weight's a steady 82 kg. I fuel my body with the right nutrition, and vitamins like Berocca, to leave me feeling energised and focused to overcome any tough day.

No trooper, no special forces operative wants to sit behind a desk. We joined up to kick some doors down.

If I've got a message to the younger generation, it's this: don't be scared of failure. Get out there, try things, and never be afraid to ask for help.

Men are very protective, and women are nurturing.

If you mind tells your body you can't do it, you will quit. If your body is giving up, but you think you can carry on, you will naturally keep putting one foot in front of the other.

A lot of people these days are very much too wrapped up in cotton wool: people aren't pushed to their limits, and that's why we should find out where our limits lie.

Basic training was hard, but I made it - because I wanted to be the best me. Sometimes you have to learn that being the best you is being the second best you. I learned the hard way that the army doesn't want people who always come first. Otherwise, there would be only one person in the army.

Being polite, being respectful, having manners, and being a socialite - they're key life skills that people take for granted. Being able to communicate with all people on all levels is what's got me so far.

Some are happy with where their comfort zone is, but I like to be constantly tested, and I think it's good.

Dad was wiped from our lives. The day after he died, every photo of him disappeared from the house. It was as if he'd never existed. Me and my brothers weren't even allowed to go to his funeral. His death was made absolute.

Followship is just as important as leadership. It's very important that you'll know if you're a great leader because you will have awesome followship. And the people behind you will take that burden of responsibility.

The Special Forces is an aggressive and violent organisation. I wouldn't want to see a woman going through that and getting shot at.

A lot of people want to go out there, help people, and save the world. Sadly, half the time they can't even help themselves.

We have a responsibility as ex-soldiers to realise we're no longer in the military. All this 'once a soldier, always a soldier', that's all well and good, but that attitude doesn't work in society.

Never, ever command respect. Always earn it. A leader steps into the arena, and a great leader should never ask anyone to do anything that they haven't done or they haven't experienced.

On a 60-mile trek with a 200-kg. bergen on my back, I felt my ankle break. Some might have given up. I broke my other ankle to even up the pain. And carried on.

I'm more about mind over muscle. My mindset needs to be the fittest, because it drags my body through whatever needs to be done. A lot of people neglect training their mind and their self-belief, but I believe that's crucial.

Don't try to be me. No one but me can be me. But you can be you. Look inside yourself and get to know who the real you is. And then be that person. The best version of you.

One minute, you're dropping your teenage son off to a festival, and the next, you're changing a nappy, but I love the versatility and challenge of being a father.

In the SAS, if you're not good enough, you're graded out of it.

When it comes to Everest, psychologically, you have to be in the red. If you're not, it doesn't matter how fit you are. I've seen the fittest of people, who I thought would steam up the top of Everest, allow the pressure to take over their body.

If you start to pass blame or responsibility on to others, that's when I'm going to start to get really angry.

I'm used to being in uncomfortable situations. I actually thrive in uncomfortable environments.

When I first joined the army, I felt I had to be part of the alpha male culture. But I didn't.

You come on my course and enter my world - I don't care who you are or where you're from - you're a number until you prove yourself otherwise.

I hate it when people are late, and I hate being late.

I was point man, which meant I was the first through the door, hunting down Taliban commanders, knocking down forts every night.

I never looked for trouble, but when it found me, I wouldn't hesitate.

I'm very confident with who I am and how I lead, and I'm a problem solver and like to keep myself on my toes.

I don't really miss anything, I'm so focussed on what I have to do - I'm so focussed on my work - that I don't miss any creature comforts.

I want to see you use your brain. Get the job done efficiently. I want to see an intelligent operator at work. And apart from that, to stay on my good side, just do as you're told.

I wanted people to know that I'm human, and I'm only successful because I've learned the hard way. I've been in so many dark places, but I got myself out.

The one thing I've always said is I don't want them growing up without a father, and they're my inspiration to make sure I'm the best man I can be. I want them to have the father figure that I never had.

I was very selfish when I was in the military - a very selfish man.

I wanted a challenge, wanted to be self-sufficient, so I thought, 'Go and join the army,' at a young age, and I just happened to be good at what I done and went up the ladder and went up to the top.

When I'm at home, I am in full Dad mode, and I love it.

Some jobs are for women, and some jobs are for men. It has nothing to do with how capable women are.

I joined the army because I was a very self-sufficient young man. I always wanted to stand on my own two feet.

The military was appealing because I could just get away and do my own thing. I could have a roof over my head, be fed, and with the little bit of money I got, I could start to build me own life as I wanted to.

I'm an extreme do'er - I'm not an intellect; I'm not a bookworm. I do, do, do, and nine times out of ten, I fail, but I learn from that.

I trained my whole career to fight. I loved my job - I prioritised by job over my family, over my children.

I was never one to think about why I need to go running or go to the gym - it just came naturally to me.

In Afghanistan, getting shot at was a regular occurrence. I viewed survival as a numbers game. As point man, every time I entered a Taliban compound first, I played the odds in my head.

The kids have got their iPads, but they prefer to get out climbing trees and coming out with me. That's the kind of learning I want them to have: experiences.

There's nothing glorious about combat. I've been there and done that.

When I took on Everest, I'm not there for the views.

I don't like to overthink. I tackle situations and problems head-on.

I'm from a generation of Iraq and Afghanistan. Our battleground was where we learned. It's not like the old generation where they used to train and train and train, and then suddenly an operation would come up, and they'd go on it.

I love dogs, but they are a big responsibility, and with four children, having one would be too much.

What's next? Let's do it! My life is chaotic and spontaneous, which is the way I like it.

Whatever I turn my hand to, I put in the effort to be the best.

I eat healthily as much as I can - meat, protein, carbs as well. I like my pasta; I like my rice. I like to have that sort of sustenance in me, because I'm always thinking of survival.

I might wake up in the morning and go out for a six- to eight-mile run, and then in the afternoon, I might swim two or three kilometres. The next day, I'll mix it up and do a military circuit. I don't stick to a set programme.

When you're in the military, you teeter on the edge of that line of life and death. The reason you feel so alive when you come through is because you know you've cheated death - and that and the adrenaline rush is addictive, no question.

It's asking that never-ending question, 'Who am I?' which motivates me and takes me on a constant journey of self-discovery that teaches me so much. Will Everest make me more cautious? In reality, probably not.

I had a tough childhood after my father died when I was five, and I had a very difficult stepfather. I want to give my children what I didn't have - a good role model.

When I was younger, if I got into arguments, I'd become aggressive and violent, but I learnt the hard way that was only going to end negatively.

I don't stick to a routine, because I like to mix things up, which stops training becoming boring and helps shock muscles into firing up.

I joined the Marines, passed Special Forces selection, and became a young leader in the military.