Tuesday, 30 November 2010

Anti-chafing and clothing advice for the ultra runner

This is my first advisory posting. Several people have said to me that I should impart some of the knowledge I have built up over the past 14 years. I have just emailed the following advice, based on personal experience learned the hard way, to an ultrarunning friend who is in training for a major challenge. While I was composing the email I thought it might benefit a wider audience, so here it is.


1. Never wear conventional underwear. It's not up to the job of so much movement for so long in damp conditions. (You will know that dampness comes from sweat even if the weather's dry.)

2. Never wear compression shorts or longs. They squash the cheeks together, increasing friction and guaranteeing chafing betwixt same.

3. If it's at all cold, avoid smooth base layers with high Lycra content (e.g. Skins, 2XU, etc.) because it's too cold on the skin, acts like a heatsink and sucks the heat out of you.

4. Never wear cotton (I bet you already knew that anyway).

5. Never wear a loose-fitting technical top as a first layer. The material acts like a file as it moves over the nipples, rubbing them raw.

6. Never wear double skin socks. The layers easily ruck up against each other, creating ridges, pressure points and blisters.

7. Never wear shoes that allow excessive forefoot movement or ANY heel movement, to reduce blistering.


1. Always wear running shorts with liner as your underwear. If it's warm it's all you need and very comfortable, indefinitely.

2. If it's cold enough for leg covering, wear tracksters (brushed material is warmer) over the shorts.

3. If it's raining but not too cold, lightweight windproof trousers (e.g. Montane, fist-sized when screwed up) are all you need over the shorts.

4. Always wear a tight-fitting base layer up top (I favour NikePro short-sleeved or sleeveless shirt, which is lightweight so doesn't suck too much heat out with its Lycra content). This allows you to wear whatever you want on top without any chafing worries.

5. Wear well-padded socks to help fix your feet in your shoes. (This depends on whether you are lucky enough to have 'shoe-shaped' feet, and how snug and comfortable the fit.) I find Thorlos to be the best.

6. As a final insurance against chafing, use a lubricant, but not petroleum jelly ('Vaseline'). It dissipates too easily when it gets warm and loses its effectiveness. For the feet I use Sportslick, plastered top and bottom. For the undercarriage regions I use 'Brave Soldier Friction Zone Advanced Skin Protectant'. Despite its dodgy name it really does work a treat. I have proven it up to well over 30 hours. Both are American products.


  1. Ah I once fell victim to conventional under-crackers but never again!

    This reminds me of this:

    Why do they always offer this so late in an event, it does make me wonder...

  2. Roger, you cracked me up again. I don't recall seeing that. Perhaps the good doctor was leaving it until the victims were quite desperate ;-)

  3. Might try the brave solider out!! Of late I've found it to get quite uncomfortable down there on any run over 10 miles! And this is mostly because of dodgy liners in running shorts!! Not all liners do the job and some do it far worst than conventional undewear! Keep the advice coming Nick!

  4. An excellent list of dos and don'ts, and it is always good to see the word "betwixt". I read somewhere once that a liberal application of Sudacrem on the feet is good for avoiding blisters, and it seems to works for me. That said, I suffer from other feet problems and can't remember when I last had ten toenails at the same time.

  5. Ordered the Brave Soldier from amazon! Bring on some chaff free running :-)

  6. i discovered body glide..works for me.i found brave soldier had a queer texture to it..but keep the lists coming nick..looking forward to your evangelical sell of coke..the elixir of.. ;-)

  7. Ali, the Sudacrem is all well and good but it's so pungent you must smell like Boots (not boots)as you waft down the trails; but if it works, who cares?

    UC, I've tried bodyglide but found its solid stick formula to be incompatible with plastering the feet and seeing to the needs of the undercarriage region.
    Was the use of the word 'queer' a Freudian slip when referring to 'Brave Soldier', by any chance? Regarding the texture, it can tend to separate into liquid and granular components, but it still works. The cold heat effect can take some getting used to.

  8. Sorry Stu, forgot to add, will you be separating it from the wheat? ;-)

  9. I use normal moisterizing cream for my feet - never had a blister in my 4 years of running :)
    and Bsc tights and -when new- didnt chafe, when they get older their stitching gets a bit rough and leave a -minor- mark

  10. If I don't wear a lycra liner underneath, it is guaranteed thigh chafe. Body Glide and similar products just wear off and there I am with no protection.

  11. I just completed Canada's first 200 mile trail run and my race almost ended with the worst ass chaffing of my life. It rained the first 24 hours and I had on normal running shorts with lining and over that long stretch pants. I had applied Bag Balm liberally. I think the tight stretchy longs pushed the short lining between my butt and the sticky bag balm glued it there. After first 100 miles I was a mess and switched shorts multiple times over the 12.5 mile loop but damage was done. Switched to white paste of diaper rash cream. Took a week for it to recover. I would have fit right in at the baboon enclosure! I was going to go with compression pants next time but you made a good point about it forcing the butt together, making things worse. At Fatdog 120 next month I'll probably go back to shorts with linings and just check periodically that it's not getting 'wedged'.