Q. Should I change my bike tyres before a race? And how do I strike a balance between durability and ride quality? A. I advise never changing anything before a race. Anything new presents an opportunity for something unexpected to go wrong. The best

, too often, you will wind up sick, injured or overtrained. Too little intensity and you will not achieve your potential in races. If you get the intensity wrong it doesn't matter if you are doing everything else right - you will not reach your full

to maintain the right technique when you begin to tire. Conditioning is traditionally done during winter to prepare you for race season. You should include exercises such as squats, lunges and step-ups. Abdominal exercises are also vital for maintaining strong

-distance record at Challenge Roth (8:18:32), breaking her own record, and she also won Ironman South Africa. She has never lost an Ironman race. She is unlikely to lose this one.Julie Dibens (UK)The 36-year-old from Salisbury came third at Kona in 2010, a

. Trainers are designed to offer a degree of shock absorption but bike shoes are stiff, to maximise your power transfer to the cranks. Efficient racingYou have to ask if, as a newcomer, the inefficiency of wearing trainers on the bike for more than an hour

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