Dear Matt,

I use my partner's old mountain bike and, after about 20 minutes, I have neckache that spoils most rides. The problem seems to be the stretch to the handlebars once I have the seat at the required height.I want to buy a new mountain bike: would a women's bike be a better fit? I'm 5ft 10in, but I'm wondering what other body measurements are useful when trying to find the right-size bike

Charlie Stebbing

Your self-diagnosis is definitely right: too much stretch would show up as stiffness and soreness at one end of your spine or the other (lower back pain is typical, too). Women tend to have longer legs relative to torso than men, so women's bikes are designed with a shorter reach for any given size.

But everyone is different: inside leg, shoulder width, arm length etc, all have a bearing on bike fitting. Ideally, you should buy from a shop that will measure and fit you first, then tailor the bike accordingly.

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· Matt Seaton's Two Wheels is published by Guardian Books at £8.99. Call 0870 836 0749 or visit guardianbooks.co.uk