Andy and Dave from Team Krypton coming into a check point on the Ultra Tour of Mont Blanc (UTMB)

Clothing for Ultra Running is all about comfort levels.  If you set off knowing you are going to be out for a good part of a day/days then you need to have confidence that your clothing will keep you comfortable under any of the conditions you may come across.  The best way to do this is to focus on getting 2 main things right. 1) the clothing that is in contact with your body; namely socks, underwear and base layers. 2) The clothing that will protect you from any adverse elements you may encounter; namely waterproofs (rain) and cap/sun hat (hot).  If you can get these right then the rest will fall into place and your clothing at least won't effect your trip!  The last and most important thing to remember is to USE YOU KIT on shorter training runs to test it works before you embark on an ultra.  So, starting from the feet and working upwards here our are recommendations:

SOCKS - VIEW RANGE

Very dependant on personal preference, try as many different pairs of socks it takes until you get one that works for you.  Ultra running is incredibly demanding on your feet so getting a sock that helps prevent blisters and excessive heat is if up most importance.  Some people prefer a sock with extra cushioning to give them some more protection which may be worth considering.  There are 2 types of specialist socks that may be worth trying if you do suffer from blistering; Hilly twin skin socks are double layered with an inbuilt liner sock that stays stationary on you foot and an outer cushioned sock that can move over the liner but not directly over your foot so you can get less blisters. Injinji tetra socks have in built individual toe compartments.  These have a real following with ultra runners as they alleviate friction between the skin between your toes.

UNDERWEAR - VIEW RANGE

Again super important to get right.  The amount if people who pay a fortune for good running tights only to put cotton underwear on underneath is incredible.  You want something that is made from a fast wicking breathable material that also offers some support to stop movement and chaffing (especially in men!). Women obviously need a good comfortable supportive sports bra, as any movement/discomfort can cause real problems over the extra distance/time you are out on an ultra.  Lakes Runner recommends ODLO underwear and base layers we can't find anything that gets close to working as well.

BASE LAYERS - VIEW RANGE

As it is worn next to the skin your base layers are the most important garments for moisture management and temperature regulation, both critical in staying comfortable.  Base layers that are worn tight next to the skin can accomplish both of these things better than loose fitting items.  More skin contact means more effective wicking of moisture and controlling of temperature.  If it is hot a light coloured loose fitting wicking T may be appropriate but if you need something for warmth it is best to go with ODLO evolution Warm or Light depending on the time of year and temperature.

SHORTS, 3/4'S AND TIGHTS - VIEW RANGE

Depending on the conditions on the day you will need to wear either shorts, 3/4's or full tights.  More and more people are going for tight cycling style shorts for ultras as they will move with your body hence create less rubbing.  The other option is a high split short as worn for fell running as these don't restrict movement or rub as much as longer shorts.  The main thing here is find a range of leg wear that works for you.

T's AND MID-LAYERS - VIEW RANGE

Not as crucial as other clothing, these need to be selected with the likely temperatures in mind. Will you need something warmer if your running through the night? If its a multi day ultra do you need something that will double as a warm layer in the evening?  Again make sure your mid-layer works for you. It goes without saying always use a technical fabric rather than cotton.

WIND PROOFS - VIEW RANGE

Depending on the kit requirements you may need either full body wind proof or full body waterproof cover.  The idea here is to get as light a wind proof cover as possible as it will spend a lot of time in your pack.  Montane Featherlite product is still hard to beat after all these years.  Its worth remembering that even if you have to carry full waterproof cover many seasoned ultra runners take a wind proof as a super light alternative to a mid layer to put on over their base layers if the wind picks up, but they don't want the reduced breath ability of a waterproof.

WATERPROOFS - VIEW RANGE

The other area of clothing that needs careful attention, being able to stay comfortable for long periods in bad weather is crucial for any ultra runner (especially in this country).  Because as the distance increase the intensity of your effort is less, i.e. you are running slower, the reduced breath ability of a waterproof is less of an issue, than it would be in say fell running.  What you should look for is light weight packable STORM PROOF cover.  For example, although Montane's Slipstream H20 is the lightest hooded waterproof on the market, it does not give sufficient protection for prolonged periods of wind and rain (1hr plus).  You are much better getting a Montane Atomic DT which, although is a little bit heavier, you know can handle anything the weather can throw at it.  Having tested lots of Waterproofs in horrible lake district weather, we only recommend ones we know keep will keep you comfortable all day!

HATS AND GLOVES - VIEW RANGE

You need to remember these if its going to be hot or cold.  A light coloured cap or sun hat can be a saviour on a hot day (or even a cap with neck protection if its going to be super scorching).  If its cold, light wickable hats and gloves are the order of the day, or slightly thicker if its super cold.  People ask about waterproof gloves, but by far the best and lightest solution is wearing your normal glove with an Extremities Tuff Bag gortex mitt over the top when you need it.

The above is intended as a guide as to what to look for in clothing for Ultra Running but it still worth following the below rules for maximum comfort:

1) Always test your clothing prior to your Ultra so you know that it works
2) Even with the right clothing Always Tape and Body Glyde any moving parts and carry spare tape/body glyde for on the road 'patch ups'.
3) For a multi day Ultra how many sets of clothing you take is up to you, lots of people like starting each day with at least a fresh pair of socks!  My personal motto is carry as little as possible and don't mind smelling!