Does exercising in the cold help you burn more calories?

Cold and calories

A 2017 study on Body fat attenuates muscle mass catabolism among physically active humans in temperate and cold high altitude environments by Cara J. Octobock found that walking in temperatures between -5 ° C and -10 ° C burns 34% more calories than at a temperature of about 10 ° C.

In the Oktobock study, 37 men and 16 women took 12-16 week outdoor courses in cold climates. Men spent about 3,822 kcal per day in spring and 4,787 kcal per day in winter. Women spent about 800 calories more in winter.

So the cold burns more calories, but does the effect extend to exercise? To understand this, you need to understand what increases energy costs in cold conditions.

Burning extra calories in the cold

In cold conditions, additional energy is spent on thermogenesis - maintaining body temperature. The human body uses two types of thermogenesis: contractile, in which the body is warmed by contraction of skeletal muscles - tremors, and non-contractile, in which the body is heated by burning brown fat and other metabolic processes.

Harvard Medical School researcher Dr. Aaron M. Cypess explains how brown adipose tissue works.

Brown fat cells contain the UCP1 protein, which converts fatty acids into heat, bypassing the phase of ATP synthesis (adenosine triphosphate - a source of energy for all processes in the body).

So, brown fat produces heat, but what does it use for fuel? In the 2016 Brown Adipose Tissue Exhibits a Glucose-Responsive Thermogenic Biorhythm in Humans study, it was found that in people with a large amount of brown fat during periods of activity of this tissue, blood sugar levels decrease, and the rest of the time it is very stable, without sharp jumps. At the same time, people with low amounts of brown fat experienced spikes in blood sugar levels.

The researchers concluded that brown fat consumes glucose and serves as a kind of buffer, helping to maintain stable blood sugar levels, which greatly reduces the risk of diabetes.

However, in most studies of brown fat, people were at rest: asleep or passively in a cold room. Even in the Oktobock study, people were walking, rather than, say, running or doing some kind of heart rate-accelerating exercise.

During exercise, thermogenesis fades into insignificance

When you warm up through intense physical activity, the body no longer needs to spend extra calories for heating and it works as usual. It turns out that the less you move in the cold, the more calories you burn due to thermogenesis, and during the most intense workout, additional calories will not be burned.

So, to burn extra calories in the winter, you can:

walk;
sleep in a cool room;
be in the cold before training.

After a workout, when you are sweating, it is undesirable to stay in the cold - this can lead to hypothermia, decreased immunity and, as a result, colds.

However, it is worth noting that training at low temperatures has many other benefits, such as increasing endurance and boosting immunity.