Do you sometimes feel like you lack energy to do everything you want to do? That you have a huge 'to do' list or lots of ideas, but you just feel lethargic and can't get going? I meet so many people with lots of passion and drive, but they are constantly tired. They can't focus or finish anything. It can be extremely frustrating when the mind wants to do one thing but the body cannot.

Perhaps another coffee or chocolate would help... But does it? Not in the long run.

I used to be a junk eater – lots of sweets, coffee all day, fast food, no water, hardly any fruit or veg – I didn't exercise; I was highly stressed and never relaxed. I thought that maybe drinking wine would slow me down and relax me, so I drunk it regularly. But none of it worked. I was constantly tired, and come 4pm, my brain just couldn't function properly. I found it hard to make decisions or be creative, even after six coffees a day! I was sleeping for ten hours a day and still waking up tired. I had digestion problems, and the worrying thing was that I thought this feeling was normal!

A friend told me to go to a Tony Robbins seminar in London. I'd never heard of him, didn't know a thing about him, but I signed up and went along. And I'm so glad I did because it completely changed my life. It was called "Unleash the Power Within", and that's exactly what it did. I learned a lot about myself, my needs and what I really want in life. I also learned how to create the energy to have it all.

Energy does not come from coffee or food but from our cells. They can produce copious amounts of energy if you give them what they need. It's actually very simple. All your cells need is oxygen, water, nutrients and the ability to eliminate their own waste. If you give them that, you will feel amazing and have an abundant amount of energy for life.

This is what happened to me. I decided to take up Tony Robbins' 10-day challenge after the seminar. It was very simple, don't eat anything with a face, no refined flour or sugar, no processed food, no dairy, no caffeine, no alcohol.

All you need is real food. So basically, fruit, veg, nuts and legumes, three litres of lemon water and a cup of wheatgrass. It seemed like mission impossible, but the key was to go shopping straight away to make a start immediately. So, I did.

I stuck with it for the 10 days and I noticed a huge difference in my energy levels. My head felt clear and I was alert all day, and, amazingly, I didn't feel any tiredness as the day carried on – an experience that was completely alien to what I was used to! I was sleeping three hours a night less and gaining 21 extra hours in the week. This was incredible!

I felt so good that I decided to continue with this challenge. I got a lot of new recipes and started making lovely and delicious food. My taste buds started changing and I didn't crave sugar or coffee anymore. All the healthy foods I used to avoid because they didn't satisfy my urges suddenly tasted rich and full of flavour. I was enjoying cooking and didn't miss meat or dairy.

My energy levels went through the roof, so I had to find a new channel to release it – so I signed up for an IronMan triathlon.

It's the hardest of any triathlon, consisting of a 3.8km swim, a 180km bike ride and a marathon to finish. It's not something people train for in a year, especially if they hadn't come from an athletic background, but that's exactly what I felt I could do with my new energy. And, despite many people's doubts, I did do it!

Then I discovered meditation, and my head cleared even more. You might be thinking though, that these new lifestyle changes and training commitments would detract from my ability to run my business? In fact, it was completely the opposite.

Wolfestone was doing extremely well, and so I wanted a new challenge. To start another business. This is when VoiceBox was created. But even that wasn't enough. I felt so motivated for success that I acquired another business – Robertson Languages International in Reading.

Everything seemed so much easier with my high levels of energy and clear head. It was fantastic. My motivation was at an all-time high and I felt so much more productive and creative. I was able to learn Spanish to a very good level in just one year. I started studying nutrition and got obsessed with it. My ambition had no bounds.

Now I'm helping a lot of people to achieve the same. I've helped my mother to reverse osteoporosis and now she has so much more energy that she hikes, rides a bike, studies languages and travels with me, and she finally achieved her target weight.

It's incredible seeing people changing their lives because of such simple changes to their nutrition and some exercise. If you would like to give it a go I recommend watching the films What the Health and Forks Over Knives. Also reading some books: Dr Gregor's book "How Not To Die", "The Blue Zones", "The China Study", "Whole: Rethinking the Science of Nutrition", and if you like sport, "Finding Ultra" and "Eat and Run". I promise it will be worth it.

I must say that now I feel like I've been reborn and have much more appetite for life. This year I've already cycled across Morocco, Peru, Bolivia, Spain, did a half marathon, starting writing, read lots of books, worked on implementing new business services, polished my Spanish and everything on top of having four companies and training for events – and it's only half way through the year.

What would you do with some extra energy? The possibilities are endless.

- Written by Anna Bastek: multi-award winning entrepreneur, inspirational speaker, owner of Wolfestone, VoiceBox and Robertson Languages International, Welsh Government Dynamo Role Model, Ironman triathlete, traveller.