OAS Health Blog
January 30, 2015
Wintertime is a beautiful time to get outside and running provides a great opportunity for exercise and enjoying the season. As with any season, running comes with the possibility of injury and greater care must be considered regarding special features of running in the winter.
There is a baseline natural stress on the body when running for exercise or race training. The cold weather and the related conditions provide additional stress factors that if considered will allow a fun and healthy running experience.
The risks of cold weather running include overuse injuries, hypothermia, frostbite, dehydration. respiratory difficulty, and winter safety issues. All of these factors can be neutralized with appropriate care and attention to specific details
Running in the cold requires care to warm up slowly. Muscles take longer to warm up in colder temperatures. Without a proper warm-up there is greater risk of injury. The muscle groups and their related tendons do not move as freely in the cold, thus subtle compensations of gait in running cannot be managed by the body. Unconscious gait changes to manage the terrain and running on uneven, snowy, slippery ground require rapid adjustments of mechanics to provide stability and support joints. Cold muscles do not react as quickly and are more difficult to adjust thus increasing the risk for muscle and tendon strains, sprains, tears, and overuse injuries. Overuse injuries are actually more common amongst runners in the winter due to the cold weather and related terrain considerations.
Safety is probably the most important initial thing to consider. Because of the snow, road conditions are changed and narrowed. There is less space for runners on sidewalks and the side of the road, forcing runners to be more exposed to traffic. Running against traffic and with care is critical to avoid unfortunate accidents. Wintertime brings with it much shorter days. In the summertime people are able to run before and after work with light. Due to the shorter days, often people run in the dark, before and after work hours. It is important to ensure that one is visible, with both reflective, bright clothing and ideally, flashlights and or a light system. With the possibility of accidents present, it is wise to have appropriate identification. An easy means of this is through the use of a RoadID (www.roadid.com). This will allow any emergency personnel to be able to identify you and contact the appropriate friends or family to assist you.
Shoe wear also is a consideration. In inclement weather and on snow and ice, traction is critical. Often a trail running shoe is advantageous due to its deeper lugs and greater treads. Another option is use of a crampon type system like Yak tracs which clip onto shoes and provide grip and traction. This is great in snow and snow/ice terrain, but less useful on mixed terrain such as urban/suburban settings where there are segments of exposed roads.
Hopothermia can be a concern when outdoors for extended periods of time exercising. Hypothemia is a decrease in ones core body temperature and normally a result of exposure. This is best addressed with appropriate gear. Ranulph Fienes, the great English adventurer and explorer famously said, “There is no such thing as inclement weather. There is just inappropriate attire.” This fits closely to runners. Clothing should be done in layers. A base layer on the skin of a polypropelene, dri-fit, coolmax type material is key. This will wick sweat away from the skin to outer layers, keeping skin dry. Dry skin stays warmer. A mid layer of synthetic like fleece or light to midweight wool product will keep the sweat from the base layer and help to transmit it to the outer layer while providing warmth. The outer layer should be a wind resistant material, ideally gore-tex that will block wind, maintain warmth and allow the mid layers to breath. Both on the body and the feet, avoid cotton. It holds moisture and provides no warmth benefits.
Overdressing is a risk as overheating will lead to increased sweating and loss of heat. A basic guideline is to dress for 15-20 degrees warmer than it is. You should be a little cold when you first start your run, and be comfortable 20 minutes into your run.
Frostbite is a risk in the cold with exposure. The body shunts blood to the midsection to the vital organs and hands and feet have decreased blood flow. Avoid this by keeping everything covered. Exposed skin under 2 degrees can freeze. Gloves or mittens, synthetic medium weight or double layered socks, and a hat or balaclava for greater coverage is useful.
Dehydration is actually a greater risk with winter running than other seasons. Runners don’t feel like they are sweating as they would in a 100 degrees July run and don’t feel they are losing water. They feel less sweating due to colder temperatures and lower humidity, but often do not appreciate the extensive losses of fluid through breathing water vapor. The body has a harder time regulating hydration when it is cold. Accordingly, one should hydrate in 15 degree january runs as they would in a mid summer run: Drinking prior to running and replenishing every half hour.
Finally, I am often asked when is it too cold to run. When the temperature, including wind chill effect, reaches zero, running outside is probably no longer healthy nor productive toward a training goal. In addition to the increased risk of injuries from the sources we have discussed, there is an additional increase risk of respiratory difficulty, even on runners with no history of asthma or other respiratory difficulties. When the difference between the temperature in your lungs and outside approaches 100 degrees your body cannot sufficiently warm and humidify the air leading to a risk of respiratory irritation and coughing which can trigger an asthmatic reaction or related respiratory difficulty. When temperature approach this level, one is better of cross training or training inside on a treadmill, eliptical, rowing machine, or swimming.
Wintertime is one of the most beautiful times to run. Crisp cold days with the beauty of fresh snow and blue skies creates a tableau for wonderful outside running. As wonderful as the winter experience can be, it is critical to pay particular attention to the variables of weather, terrain, and seasonal changes to ensure that runs are enjoyable and allow us to achieve our goal from the training session.