Changes

* '''[[Hypothermia]]'''. [[Hypothermia]] can occur when the temperatures are =Cold and Wet=When talking about running in the 50s if you are cold or exhausted, we have to look at how being wet changes things. See [[Hypothermia]] for details on this dangerous condition.When the temperature is above freezing, we can become wet through the rain, but regardless of the temperature we can always become wet through our own sweat. Getting wet makes the cold worse for a number of reasons:* '''The 20 degree ruleBeing wet increases heat loss through evaporation.''' A good approximation is to dress for temperatures that are 20 degrees Fahrenheit warmer * Wet clothing provides vastly less insulation than the actual temperaturedry clothing. Different materials can have different residual insulation properties when wet. So if it's 20 degrees out* Your body regulates its temperature by blood flow to the skin and by sweating. If you're wet, dress for walking in 40 degrees. [[Perceived Temperature For Runners]] will give you a more accurate estimate. * either through rain or sweat soaked clothing, your body can'''Dress in layerst control its temperature by sweating, only blood flow to the skin.''' Layers will keep you warmer than a single layer, and allow for flexibility of removing some of * Cold rain can directly reduce your body temperature by carrying the heat away as it runs over your insulationbody.* '''Shed after warm-up=Common Mistakes=[[File:RunningInTheCold.''' If practical, you can overdress for png|none|thumb|200px| A chart showing three possible temperature changes over time when running in the first mile or socold.]]The chart above shows the ideal temperature changes include, until you warm up. This requires you having somewhere to discard and the extra clothes, or a way of carrying themtwo common mistakes in blue and red.* '''If your hands are coldThe green line represents the ideal temperature changes. The runner starts off slightly cool, wear a hatand warms up during the first part of the run.''' This is an old boy scout sayingOnce the runner has warmed up, they shed clothing, but it worksor undo zippers to maintain their temperature of the right level. If you core temperature starts to drop, your body will protect your vital functions * The runner represented by sacrificing your extremitiesthe blue line warms up nicely, such as hands and feetbut does not shed sufficient clothing.As a result they sweat excessively, soaking wet clothing and become chilled.* '''If your hands are coldThe red line shows a runner that does not shed closing, wear [[Arm Warmers]]and overheats.''' If you suffer from While it is strange to think of heatstroke while running in the cold hands, then [[Arm Warmers]] may be the keyit is possible. If your arms are cold, the blood flow A reasonably well trained runner is likely to your hands is both chilled simply slow up and restrictedwill perceive the heat stress as tiredness. * '''Don't sweat throughThis is because the subconscious responds to the rising core temperature by reducing [[Muscle| muscle recruitment]].''' If you wear too many clothes and sweat too muchHowever, you will sweat through your clothes. Once your clothes are soakedan untrained individual may raise their core temperature to rapidly, you will become suddenly chilledand suffer heatstroke. This means you will probably have to dress to be slightly  =Staying Warm While Running in the cold, rather than toasty warm.=* It'''Windproof layers are a mixed blessing'''. A windproof layer s tricky to maintain the right temperature when running in the cold because your sweat will boost reduce the insulation value of the underlying layers, which your clothing. There are several approaches you can really help keep take to overcome this. * '''Stop before you warm're cold'''. Unfortunately a windproof layer also stops sweat evaporatingA common approach is to be slightly overdressed, which regulates but to stop running before your sweat soaks your temperatureclothes to the point you get cold. This makes it much more likely that works well for shorter runs, but you will sweat though and become coldcan't run long distances this way. * '''Change clothes. I use a windproof layer'''This requires some logistics, but open it up 's possible to change clothes as soon as I warm up, then try to stay slightly cooleach set becomes soaked. A windproof layer is very useful as an extra layer, as * '''Stay dry'''. Staying dry while running in the cold is harder than it can be wrapped around your waist easilysounds. I will wear You either have to avoid sweating or make sure that all the sweat evaporates before it until I warm builds up, then carry it in case I need some extra warmth later and soaks your clothing. This can work in mild conditions where you are wearing thin thermal layers that allow for good sweat evaporation, but as you put on more clothing, the harder it is for the runsweat to evaporate.* For some runners, especially smaller and slower runners, it'''Hydrates possible to run and not sweat much, but for most of us, running results in high sweat rates.If it''' Just because s raining, it's cold doesn't mean hard to stay dry as any waterproof layer you don't need to drinkwear will prevent your sweat from evaporating. Use your thirst as a guide - for more on hydration see [[Practical Hydration]] (Breathable waterproof material rarely keeps up with the high sweat rates of runners, and [[Hydration 101]]ironically the breathability drops dramatically when the outside of the material is wet.)* '''Try to stay dry.Wetsuit. ''' Rain The wet suit approach is to wear sufficient layers to be warm even when soaking wet. This can chill you very quicklywork reasonably well, so and it's often the only viable approach in cooler conditions, you need some cold rain protection. More on this This approach causes your clothing to become heavy with water, but there is a wide variation in [[Running how different clothing behaves when soaking wet. Having your skin immersed in the Rain]].* '''Your lungs are finecold water can cause problems with maceration (the prune effect), including chaffing, [[Blister Prevention| blistering]], immersion injuries and chilblains.In cold rain it can be important to have a waterproof layer; this is not to keep you dry, but to prevent the cold rain from washing over your skin and chilling you. * ''' Your lungs will Double waterproofs.''' While it's not freezepossible to keep you dry, not even at -40 degreesit is possible to keep your clothing dry. Your lungs may get irritated by the low humidity, but they will get used to This approach uses four layers of clothing. The first is a base layer thatkeeps your soaking skin somewhat comfortable. It Next there is possible to get exercised induced asthmathe first waterproof layer that prevents your insulating clothing from getting soaked from the inside by sweat. The third layer is the insulation, which may actually consist of multiple thin layers of insulating clothing. Finally there is a narrowing of second waterproof layer that keeps the airways when exercisingrain from soaking the insulation from the outside. If you suspect This is a difficult combination to get right, as you do not have this condition, seek medical advicethe ability to regulate your temperature through sweating. Therefore the risk of heatstroke is quite high, so be careful. =General Tips=* '''No cottonThe 20 degree rule.''' This A good approximation is true to dress for any conditions, but worth restating heretemperatures that are 20 degrees Fahrenheit warmer than the actual temperature. Wear clothes made from syntheticSo if it's 20 degrees out, wicking fibers, such as CoolMaxdress for walking in 40 degrees.* '''Watch for frostbite.''' Your extremities may go numb early in your run* The faster your run, the more heat you generate, but they should warm upso the less insulation you need. Anything that stays numb needs The same temperature will feel different to be checkeddifferent runners based on their height, weight and pace.* '''Watch for ice.''' Slipping * This is a simplified rule, and the details depend on ice can pull muscles or cause falls. You can get pace, height and weight; [[[Traction AidsPerceived Temperature For Runners]] to attach to your [[Shoes]] if ice is a significant problem. See [[Traction Aids]] for more detailswill give you a more accurate estimate. * '''Hat and glovesDon't sweat through.''' These are important to keep If you warmwear too many clothes and sweat too much, you will sweat through your clothes. Once your clothes are soaked, but they can also be taken off and tucked in a waist band easily. This allows you to adjust your insulation for the conditionswill become suddenly chilled. I like gloves that convert into mittens (more on these in a future blog)* * '''Stay Cool'Vaseline.''' If . To avoid excessive sweating, you are still having problems with your hands and feetshould aim to feel slightly cool, spreading Vaseline over them before putting on your socks or gloves will dramatically improve the insulationrather than comfortably warm. ItDon's a bit strange the first time t get so cold that you do itshiver, but it works very well's okay to feel chilly.* '''SunglassesHydrate.''' Keeping Even in cold weather hydration is important. Use your eyes protected can help you keep thirst as a little warmer, guide and reduce how runny your nose gets. I use Oakley sunglasses with interchangeable lenses, so I can use clear glass when it's darkfor more on hydration see [[Practical Hydration]] and [[Hydration 101]].* '''Chemical WarmersNumbness is bad.'''. Using chemical warmers can help keep Your extremities may go numb early in your hands from getting too coldrun, but they should warm up. I find these seem Anything that stays numb needs to not only keep my hands warmbe checked as this can result in frostbite or other cold injuries. Beware anything that restricts circulation, such as elastic cuffs, but also provide some extra warmth to as the rest of my body and a little phycological boost. You reduced blood flow can warm the packs with a hairdryer contribute to get them extra warm (Thanks to Megan H)*frostbite.* '''Watch for ice.''' Slipping on ice can pull muscles or cause falls. You can also save the hand warmers for another run by putting them in get traction aids to attach to your shoes if ice is a sealed bag with the air squeezed outsignificant problem. See [[Traction Aids]] for more details. (Thanks Charles/Kristine)* '''Neck Warmer.Emergency trash bag''' A fleece neck warmer . If things go badly, a trash bag can protect your face and neck from the coldhelp keep you warmer, especially if you have to stop running. I use You can fold a Turtle Fur neck warmer ([http://wwwtrash bag up quite small and tuck it in your waistband.rei ==Clothing==* '''Adjust Your Clothing.com/product/663041 http://www'''It is of most importance that you adjust the amount of insulation you get from your clothing as the conditions change.rei.com/product/663041])Trying to make sure that your clothing is as flexible as possible.* '''Warm Up InsideZippers are your friend. '''. Often And one of the first mile or so is best ways of adjusting the worst, as insulation you get from your body has not started clothing is to have zippers.''' '''Zippers on jackets and clothing allow you to produce sufficient heat quickly and adjust the amount of insulation to offset the cold. Warming up for 10 minutes insideconditions, by running up and down stairs, doing and they can provide a jump rope, or using a treadmillfine grained adjustments. (Thanks to Melanie M for this tip)* '''Start into the windDress in layers.'''. If it's windyLayers will keep you warmer than a single layer, start and allow for flexibility of removing some of your run into the wind so that on the way back, you woninsulation. * '''Tuck in or hang out'''t freeze due to sweating. (Thanks Tracking your upper body layers into the waistband of your tights can make a surprising difference to Bobby A for the effectiveness of the insulation. When they are tucked in, air circulation is reduced and insulation is improved. Conversely, you can pull the tops loose and the air circulation will reduce the insulation, and improve sweat evaporation. You can even have your top tucked in at the front and out at the back, which keeps the Windward side of you warmer and your sheltered back a little cooler.* '''Strip off after warm-up.''' If practical, you can overdress for the first mile or so, until you warm up. This requires you having somewhere to discard the extra clothes, or a way of carrying them. An alternative is to have clothing with zippers so you can reduce your insulation. * '''Windproof layers are a mixed blessing'''. A windproof layer will boost the insulation value of the underlying layers, which can really help keep you warm. Unfortunately a windproof layer also stops sweat evaporating, which regulates your temperature. This makes it much more likely that you will sweat though and become cold. I use a windproof layer, but open it up as soon as I warm up, then try to stay slightly cool. A windproof layer is very useful as an extra layer, as it can be wrapped around your waist easily. I will wear it until I warm up, then carry it in case I need some extra warmth later in the run. * '''Base layer'''. I recommend a close fitting, very thin base layer. The goal of this tipbase layer is not to provide insulation, but to spread out the sweat, and prevent chafing. I typically run in an [[UnderArmour HeatGear Top]].* '''Hat and gloves.''' These are important to keep you warm, but they can also be taken off and tucked in a waist band easily. This allows you to adjust your insulation for the conditions. * '''Windproof underwear'''. For men, wearing underwear with a windproof front can provide vital protection. * '''Protect the front'''. Wearing tights and top that are thicker and/or windproof on the front provide warmth while preventing overheating. The [http://www.golite.com/Mens-Black-Mountain-Thermal-Wind-Jacket-P46654.aspx Go Lite Black Mountain jacket] is excellent. * '''No cotton.''' This is true for any conditions, but worth restating here. Wear clothes made from synthetic, wicking fibers, such as CoolMax. * '''Wet insulation'''. Different materials can have very different characteristics when they are wet.** '''Insulation when soaked'''. Some materials are much warmer when they are completely soaked. Wool has a reputation of being one of the better materials for retaining warmth when wet. However any soaking wet material will cause you to lose heat through evaporation unless there is a windproof layer over the top.** '''Weight when soaked'''. I've found that some synthetic tops become surprisingly heavy when soaking wet. I don't know of any way of predicting this behavior other than trying it out.** '''Breathability. '''Some thermal layers will breathe well and allow sweat to evaporate before the government is soaked. This is good, as it allows your body to control its temperature through sweat affectively. Other materials do not breed so well and so the sweat will not evaporate until the government is completely soaked, at which point your temperature is likely to drop rapidly.* '''Neck Warmer.''' A fleece neck warmer can protect your face and neck from the cold. I use a Turtle Fur neck warmer ([http://www.rei.com/product/663041 http://www.rei.com/product/663041]). * '''[[Sunglasses]].''' Keeping your eyes protected can help you keep a little warmer, and reduce how runny your nose gets. I use [http://www.amazon.com/Oakley-Half-Jacket-2-0-Sunglasses/dp/B007EN0FL0 Oakley Half Jacket sunglasses] with interchangeable lenses, so I can use clear glass when it's dark, or the cheaper and more convenient [http://www.amazon.com/Tifosi-Tyrant-Sunglasses-Gunmetal-Fototec/dp/B002Q1F1AA Tifosi Tyrant sunglasses] that have photochromic lenses that go nearly clear in dark conditions.  ==Cold hands or feet==* '''If your hands are cold, wear a hat.''' This is an old boy scout saying, but it works. If you core temperature starts to drop, your body will protect your vital functions by sacrificing your extremities, such as hands and feet. However, this is a delicate balancing act, as you need to stay cool enough that you are not sweating excessively.* '''If your hands are cold, wear arm warmers.''' If you suffer from cold hands, then [[Arm Warmers]] may be the key. If your arms are cold, the blood flow to your hands is both chilled and restricted. * '''Chemical Warmers'''. Using chemical warmers can help keep your hands from getting too cold. I find these seem to not only keep my hands warm, but also provide some extra warmth to the rest of my body and a little physiological boost. You can warm the packs with a hairdryer to get them extra warm (Thanks to Megan H). You can also save the hand warmers for another run by putting them in a sealed bag with the air squeezed out. (Thanks Charles/Kristine).* '''Vaseline.''' If you are still having problems with your hands and feet, spreading Vaseline over them before putting on your socks or gloves will dramatically improve the insulation. It's a bit strange the first time you do it, but it works very well. * '''Convertible Mittens'''. I've found that the gloves that include a cover to convert them into mittens work remarkably well. My favorites are the [http://www.amazon.com/Saucony-Womens-Ulti-Mitt-Large-Vizipro/dp/B006ZW6L4Q Saucony Ulti-Mitt]. * '''Latex Gloves'''. One runner has suggested using the thin latex gloves under their usual gloves. The latex gloves act as a vapor barrier, creating a "dry suit" (see above) for your hands . ==Extreme Cold==* '''Your lungs are fine.''' Your lungs will not freeze, not even at -40f/-40c. Your lungs may get irritated by the low humidity, but they will get used to that. (It is possible to get exercised induced asthma, which is a narrowing of the airways when exercising. If you suspect you have this condition, seek medical advice.)* '''Suck then blow'''. If you have a problem with the tube on your hydration bladder freezing up, blow air back down the tube each time you have finished drinking. The drink is unlikely to freeze in the bladder itself, but the tube is very hard to keep warm. Insulation around the tube helps a bit, but not enough. (Thanks to Ron Bowman for this tip)

* '''Windproof underwearCover gaps'''. For menBelow 0f/-18c, it is critical to ensure there are no gaps or exposed skin. The phrase 'exposed skin freezes in minutes' should be taken seriously. * '''Warm Up Inside'''. Often the first mile or so is the worst, as your body has not started to produce sufficient heat to offset the cold. Warming up for 10 minutes inside, by running up and down stairs, doing a jump rope, wearing underwear with or using a windproof front can provide vital protection[[Treadmill]]. (Thanks to Melanie M for this tip.) * '''Protect Start into the wind'''. If it's windy, start your run into the frontwind so that on the way back, you won't freeze due to sweating. (Thanks to Bobby A for this tip.)  =Cold Injuries=There are four main cold injuries you need to consider as a runner.  ==Hypothermia ==''Main article: [[Hypothermia]]'' Hypothermia is the obvious and most serious problem, which is when your core body temperature drops. Wearing tights Hypothermia can kill and top that can occur in relatively mild conditions. There are several ways runners are thicker likely to get hypothermia:* Probably the most common is when a runner does not adjust their clothing and/or windproof on sweats through. Once their clothing is saturated, they rapidly become chilled. This can occur relatively quickly, especially when the sweat reaches the front provide warmth while preventing overheatingsurface.* A sudden downpour can rapidly chill a runner. The [http://wwwrain can saturate clothing which reduces its insulation, and heavy rain can wash over the skin taking heat with it.* A runner may be appropriately dressed while running, but should they be forced to stop, they can become rapidly hypothermic.golite* A sudden change in weather conditions can occur.com/Product/ProdDetailTypically this is an increase in wind speed, or the drop in temperature that occurs at sunset.aspx?p=AM1352|Go Lie Black Mountain] jacket Shivering is excellentthe first warning sign of hypothermia. If you are shivering, you should do something to remedy the situation:* If you'''Emergency trash bag'''ve stopped running, and are able to start again, then do so.* If you can put on more clothes, or zip up/tuck in the clothes you have, then do so. * If things go badlyneither of these options is available to you, then try to seek shelter as quickly as possible.Another symptom of hypothermia is the "umbles" – stumbles, grumbles, mumbles. This is because mental functioning declines with hypothermia, which also results in a trash bag decline in the ability to make good decisions. Watch out for those around you the symptoms of hypothermia.  ==Frostbite ==Frostbite is when your flesh becomes frozen and can help keep you warmerlead to permanent damage. The signs of frostbite are numbness, waxy or unusually firm skin, but often the victim of frostbite is not aware of the problem until too late. * Maintain circulation.** Reduced circulation is a key risk factor for frostbite, so avoid any constricting shoes, clothing or jewelry.** Stay warm as your body will reduce circulation to your extremities to preserve your core temperature.** Avoid dehydration, as this may reduce circulation.** Be especially careful if you are on medication or you have a medical condition that reduces circulation.* Protection from the cold.** It is important to stop runningprotect your extremities, especially under severely cold conditions. Even without wind, exposed skin can become frostbitten in 30 min. when the temperature is -15c/5f. (See the chart below for more details.)* Treatment. * '''Cover gaps'''* If you suspect frostbite, you should seek professional medical help. Below 0f/** Do not attempt to re-18cwarm a frostbitten extremity unless definitive medical care is more than two hours away.[[File:windchill.gif|none|thumb|500px|NOAA frostbite risk chart.]]For more details, it read [http://www.wildmedcenter.com/uploads/5/9/8/2/5982510/wms_frostbite.pdf Wilderness Medical Society Practice Guidelines for the Prevention and Treatment of Frostbite]. ==Immersion injury ==Immersion injury occurs when your skin has been soaked in cold water for long periods of time (hours). Immersion injury occurs in water temperatures between 59f/15c and 32f/0c. This is critical different to ensure frostbite because the skin is not actually frozen, but there is still cold damage to the cells. (Immersion injury is sometimes called trench foot.) ==Chilblains ==Chilblains are damage to the skin from rapid warming. Typically the conditions that cause chilblains are no gaps or exposed similar to immersion injury, but the damage of chilblains can be reduced by slow warming. (There is some degree of genetic predisposition to chilblains.) After a long run in cold conditions, it is best to allow your skinto come back to normal temperatures slowly, rather than jumping into a hot shower. The phrase 'exposed If you do reform your skin too rapidly, you may get a burning itching sensation over the affected skin freezes , or in minutesextreme cases blistering. I've found that turning the shower as cold as it will go can help reduce the burning and itching, but that's thoroughly unpleasant when you' should be taken seriouslyre feeling chilled after a long cold run.