While most running gear cuts across the genders with only minor variations - shoes, shorts, tops, caps and the like - one essential running item is strictly ladies only: bras. So guys, come back next week because today I'm talking boobs, specifically bras that owe more to structural engineering than Sports Illustrated.
When it comes to bras and running, it seems the more utilitarian the better. Merely fishing something out from your knicker drawer isn't going to cut it either, although a survey of women in the UK found 73 per cent of those who exercise regularly do not wear a sports bra.
Why is a sports-specific bra important? Because the delicate connective tissue within the breast known as the Cooper's ligament can be strained and stretched by movement, which in turn can lead to irreversible breast sagging (Cooper's droopers anyone?).
Research conducted by the University of Portsmouth for sports bra maker Shock Absorber, using a "bounce-o-meter" no less, found even women with an A cup averaged 4cm of movement when running with no bra.
Perhaps unsurprisingly, by the time you got up to a G cup that measurement was 14cm.
The research only considered the sponsors product but it did show a sports bra cut movement by around 60 per cent regardless of bra size.
Claire Long, owner of Newmarket lingerie store Avokado, has given me some tips on purchasing this essential bit of kit. Her store specialises in bras for the bigger busted and stocks a range of sports bras running from a D cup up to an HH cup. Having said that, her advice on sports bras is relevant for women of any breast size.
Long is herself just getting back into running. She ran as a teen but gave up when a big bust and ill-fitting bras made for an uncomfortable mix.
Long says runners need a bra that reduces movement and stretching of the breast tissue, but most importantly of all, is comfortable.
"Some people want to look good but it's really all about functionality," she says.
While every woman will suit a different bra it is important to get fitted properly, says Long.
This means getting a professional fitting done, rather than ducking into the changing rooms with a bundle of bras before emerging 5 minutes later with a "winner".
Long says 80 to 90 per cent of women are wearing the wrong bra size, with the majority in a bra that is too big in the band and a cup that is too small. She says Avokado often have women come in saying they are a 12DD and walk out with a properly fitted bra in an 8G.
Her advice is to ensure that the band around the bottom of the bra is a snug fit. Unfortunately this may mean the dreaded "back fat" spill-over.
She says 80 per cent of the support comes from the band, so if you slip your shoulders out of the straps the bra should stay in place.
The breasts also need to be fully encased in the bra meaning no spillage out the sides and a style that gives good coverage over the entire breast.
Long also recommends getting a bra without an underwire as it is more likely to still fit even if you lose or (gulp) gain some weight.
And speaking of weight, don't be tempted to get a smaller size thinking you'll fit into it further down the track when you lose some kilos. Buy a bra that fits now because your boobs are the last place the weight comes off.
Finally, have a good jump up and down in each bra you're trying on. Make sure it's not a tentative little jiggle either - you need to make sure your boobs are moving as little as possible. If you're anything like me, you'll find your boobs are rock solid while the rest of you wobbles like a blancmange in an earthquake. Check your ego in at the door.
A good sports bra is a bit of an investment piece so expect to pay around $100. Depending on how regularly you use it and look after it between runs.
Bras are best handwashed but given that handwashing is at the bottom of most "to do" lists a gentle machine wash is the next best thing. Always do up the hooks and use a lingerie bag to wash it in. Never ever chuck it in the dryer to get it dry.
You'll know it's time to get a new one when you're doing it up on the last set of hooks and the band is creeping up your back. This means your breasts are no longer as well supported as they once were.
In other news:
* Women's marathon champion Paula Radcliffe on nine times New York Marathon winner Grete Waitz, who died of cancer this year aged 57.
* GPS training watches are not all that accurate, playing havoc with training.
* Drug cheats will be back in Olympic teams if rules are changed, says British Olympic Association head.
* Work off some of the Christmas Day excess with a dash to the top of Mount Maunganui. Categories for kids and if you're not up to a hike to the summit there is a run/walk event around the base track.