Is It Ever Too Cold?

Environmental physiologist David Bass noted, “Man in the cold is not necessarily a cold man.” The consensus from the research is that it is never too cold to exercise – regardless of fitness level.{{more}}

Exercising in the cold safely and comfortably is dependent on heat regulation – balancing the production and loss of heat. Both too much and too little heat can lead to hypothermia. If you don’t have enough of the right clothes, then your body loses heat faster than it can produce. But, if you are too warm, then you will release heat (sweat). Wet skin and wet clothes signal the body to continue the heat loss which then becomes a vicious cycle that can also lead to hypothermia.

Where does this heat come from? For cold weather exercise, the two primary processes are basal energy expenditure (shivering) and muscular activity (movement). To have a positive outdoor experience, it is certainly more enjoyable and more efficient to move rather than to stand and shiver.

Conservatively estimate your time outside until you know your limits. Just because you can ride a bicycle for hours outside in the summer, doesn’t mean you can expect to jump into that same ride in the winter. If you are a seasoned skier and suddenly decide to ride that bike you haven’t touched in years, best not to expect an extended winter ride your first time out.

How cold is cold? Frostbite can’t occur at temperatures above freezing, 32ŗF. Prolonged exposure of extremities with a thin epidermal layer (hands, feet, ears, nose) to temperatures in the teens can lead to frostbite.

Winter air is dry. It doesn’t hold the moisture that warm air does and consequently can irritate the airways and trigger bronchospasm or asthma exacerbation. A winter face mask can warm and humidify the air reducing irritation.

Hydration is still important. Dehydration can occur if fluid intake is substantially lower than fluid lost in sweat.

Age is a factor. People over 60 may be less cold tolerant due to reduced vasoconstriction, which is the narrowing of the blood vessels to retain body heat. They also experience a decline in physical fitness, and can lose heat more quickly.

Tip #1: Dress properly. Begin with a lightweight moisture wicking baselayer and an insulating layer over that. The insulating layer traps air which gets warm from your body heat. A shell layer is the outer layer that both protects the body from wind while allowing sweat to escape. Shell layers perform best when worn during rest periods or in wet or windy conditions. Always wear a hat and cover your ears. A lightweight balaclava will both breathe, keep you warm and prevent frostbite on your ears.

Tip #2: You should feel cool before you begin exercising outside. You will easily generate that insulating layer of warm air. If you feel comfortable, you are overdressed and you will quickly sweat.

Tip #3: Take only short rest periods, just enough to catch your breath, but not long enough to cool down and begin to feel the baselayer get cold.

It’s never too cold to be outside. It just takes longer to prepare.

Information for this article was taken from:

Castellani, John W., et al. Prevention of cold injuries during exercise. No. MISC06-03. Army Research Inst Of Environmental Medicine Natick Ma Thermal And Mountain Medicine Division, 2006.

Carlson, Mark J. “Exercising in the Cold.” ACSM’s Health & Fitness Journal 16.1 (2012): 8-12.

Lesley is a health and fitness professional providing a balanced approach toward a healthy lifestyle. She can be reached at