At this point in the year, many multi-sport athletes will take their training indoors. This can especially be seen with running. Many athletes shun the cold and will take their run training indoors to the treadmill.
Treadmills can be very valuable tools. For example, Hunter Kemper, the #1 ITU Triathlete in the World in 2005, does almost 80% of his run training on the treadmill. Not only is a treadmill more cushioned than the hard concrete or asphalt, it is also a great training tool for intervals and other workouts such as tempo runs. This is because you can set your pace for the interval and not worry about other outside factors such as Heat, Cars, and other environmental factors.
This being said, it is also very beneficial to brave the cold weather and run in the outdoors during the winter time. Not only will you get used to the cold, you will also teach your body to maintain an even pace without having to maintain an even stride length or cadence. You will also give your body the jolt of an increase in heart rate at times due to hills. Most of all, you will experience the outdoors the same as in the race.
For more information about training in the outdoors during the winter, check out this article. And for more information, feel free to email Jamie at email@example.com.