The recent Arctic conditions of consistent sub-zero temperatures and snowfall prompted me to write this piece. It’s written especially for those who must continue to exercise outdoors or in equally tough conditions in home (garage) gyms and pain caves.
How does temperature affect the body when exercising?
Any process that requires energy is affected by temperature and in the case of muscles, a drop in temperature slows down the energy to work process. Notice I’ve avoided using the word contraction as energy is required by the muscles in order to relax (for the myosin filaments to let go of the actin filaments). This relaxation after a contraction is delayed even in moderately cold environments. The problem then occurs when the next voluntary muscle contraction is imposed on a muscle that is still relaxing. This could result in impaired performance and early fatigue or in worse cases muscular injury.
There is also an increased reliance on anaerobic metabolism and glycogen stores at any given work rate as aerobic pathways are inhibited by the blood flow changes associated with the cold.
Clothing Strategies for exercising in the cold
- Cover as much skin as possible to reduce wind chill heat loss. Especially important for cyclists’ legs due to the higher speed of travel.
- Dress in layers so that you can dress up or down as needed. The base layer should be fast wicking as sweat held against the skin will cause heat to be lost more quickly from the body. A thermal mid layer may be needed and finally a wind/waterproof outer layer.
- Choose appropriate gloves, socks, booties (overshoes) or facial/head coverings. Proportionately more heat is lost through the skin of the palms, soles and cheeks due to the arrangement of blood vessels in these areas.
Warm-up / pre-heating
- A greater amount of time spent bringing body temperature up before the start of the race or training intervals may be required. This could include typical active warming up or the use of passive heating measures (such as heated clothing, air conditioning, hot baths etc…). Check out our ultimate running warm up here.
Nutritional Strategies
- Choose warm snacks or drinks when possible. All cyclists love an excuse for a café stop!
- Eat regularly; the process of digestion produces a little heat within the body.
- Ensure that you take in sufficient carbohydrates via drinks, gels and bars on colder days to prevent ‘the bonk’. This may need to be a little more than you typically take in when its warmer.
