He rowed the Atlantic, cycled the Arctic and won two Olympic golds: James Cracknell's latest physical test was completing the "Duracell Wheel of Endurance", six punishing physical tests across six rotations of the EDF Energy London Eye.
Working in partnership with Duracell, experts in smart power solutions, Cracknell is on a mission to encourage others to achieve their own goals. And as a seasoned athlete and adventurer, his tips for success are bound to power-up your own challenge ...
Make a plan "Start by setting a target of how many hours you can commit – and stick to your schedule."
Pal-up with a friend "Not everyone has a personal trainer, so find a friend who's planning a similar challenge. There will be times when they're feeling motivated and you're not and vice versa: help each other through it."
Train hard "Make your training tougher than the actual event. For the marathon, I ran faster in training, so I wouldn't have to be as quick on the day."
Eat right "You need a certain amount of calories in 24 hours, but consume most of them early to burn them off throughout the day."
Listen to your body "Sometimes your body tells you what you need to eat. I ate pork scratchings in the Antarctic – but I haven't touched them since."
Sleep in the bank "You'll be nervous the night before, so make sure you get a good night's sleep the night before that."
Set realistic targets "If you haven't run for 10 years, you're not going to run a marathon instantly. But you can run a mile, and the week after that you can run two – eventually you'll get there."
Get your gadgets "Take a camera to show friends and family where you were, a powerful torch and a GPS: tough, old explorers may turn in their graves but I like knowing where I'm going and how quickly I'm getting there! And don't forget your Duracell batteries to keep you powered up."
Appreciate the opportunity "You'll have difficult moments, but you've sacrificed precious time with friends and family to do this – you owe it to them to enjoy it."
Put yourself to the test

Whether it be learning to swim, running a marathon, or setting yourself goals at home or at work, taking on any kind of challenge is a great way to learn new skills, make new friends and test your endurance.
If you're ready for a challenge, you can share your goals and get support from the Duracell community at the Duracell Facebook page, facebook.com/duracelluk, as well as explore how to power-up the gadgets that make your training more successful and fun with long-lasting Duracell batteries.
Boost your challenge
The longest lasting battery powers the longest lasting challenges. Watch James Cracknell complete the "Wheel of Endurance" challenge at youtube.com/officialduracelluk