Rapid response: with cold you also lose fluid (by sweat under clothing and by breathing), but you are less thirsty: exposure to cold attenuates the feeling of thirst (Kenefick et al., 2004) and increases urine production (Castellani and Young, 2016). That's why you should drink with a plan: start well hydrated, drink according to your sweat rate in long sessions and weigh before and after to know how much to replenish (ACSM; Sawka et al., 2007).
Importance of hydration in cold weather
Hydration is an essential component to maintain optimal performance, regardless of room temperature. However, in cold climates, the importance of adequate fluid intake is magnified by unique conditions affecting the human body. In this section, we will explore how cold weather impacts the body, the differences in hydration from warm climates, and the benefits of maintaining adequate hydration.
Impact of cold weather on the body
The cold climate presents specific challenges for the human body. As temperatures fall, the body works more to maintain its internal temperature, which can increase energy spending. This process, known as thermogenesis, can lead to greater fluid loss through breathing and perspiration, although the latter is not as evident as in warm climates.
In addition, cold can suppress the feeling of thirst, leading to insufficient fluid intake. This is particularly problematic for outdoor athletes, as they may not realize that they are dehydrated until the effects begin to affect their performance. Dehydration in cold climates can result in decreased cognitive function, increased risk of injury, and slower recovery.
Differences in hydration from warm weather
In warm climates, sweating is the main route of fluid loss, and the need to replenish these liquids is more obvious. However, in cold climates, fluid loss often occurs more insidiously. Breathing in cold and dry air can result in significant water loss, and the use of heavy clothing for cold can increase sweating without being evident.
It is crucial to remember that, although visible sweating may be lower in cold climates, fluid loss remains significant. Therefore, the hydration strategy should be adjusted to compensate for these differences.
Benefits of adequate hydration
Maintaining adequate hydration in cold climates offers multiple benefits that are essential for performance and health. Optimum hydration helps regulate body temperature, which is crucial to prevent hypothermia and other cold-related complications. It also supports cardiovascular function, allowing the heart to pump blood efficiently to the active muscles.
Hydration is also vital for the proper functioning of the immune system, which may be compromised in extreme cold conditions. For athletes, proper fluid intake improves endurance, strength and recovery, allowing them to train more effectively and safely.
In doing so, not only is performance optimized, but long-term health is also protected.
Good practices
Maintaining adequate hydration in cold climates is crucial to optimize physical performance and prevent health problems. Below are some good practices that will help you stay hydrated properly during your cold workouts.
How to calculate the amount of water needed
Determining the amount of water you need to consume daily can be a challenge, especially in cold climates where the feeling of thirst can decrease. There is no daily figure valid for everyone: it depends on your size, training and environment. One practical way to monitor it is the color of urine and weight in the morning, and in long sessions, the difference in weight before and after (Sawka et al., 2007).
Best times to hydrate during exercise
The timing of fluid intake is as important as the amount.
- Before exercise: Drink with time: ACSM proposes about 5–7 ml per kg of weight at least 4 hours before if you are not well hydrated (Sawka et al., 2007).
- During the exercise: Drink according to your sweat rate, which you can estimate by weighing; the goal is to avoid losing more than 2% of body weight in the session (Sawka et al., 2007).
- After exercise: If you are in a hurry to recover, ACSM suggests drinking about 1.5 liters per kg of lost weight, along with some sodium (Sawka et al., 2007). Weighting before and after exercise may be helpful in calculating this loss.
Use of isotonic beverages and electrolytes
In cold climates, although sweating may be less evident, electrolyte loss remains significant. Isotonic drinks can be an excellent option to replenish these electrolytes and maintain the body's water balance. These drinks are formulated to contain similar levels of sugar and salt to those of the human body, which facilitates rapid absorption.
- When to use them: They are especially useful during prolonged or high intensity activities, where simple water is not enough to replenish sodium and potassium losses.
- How to choose them: Opts for drinks containing a balanced mixture of carbohydrates and electrolytes.
Common errors
In the context of hydration during cold weather, it is easy to fall into certain errors that can negatively affect performance and health. Below, we analyze some of the most common errors and how to avoid them to ensure proper hydration.
Underestimating water need
One of the most frequent mistakes is to underestimate the amount of water the body needs in cold climates. Often, the feeling of thirst decreases when temperatures fall, which can lead to insufficient fluid intake. However, the body continues to lose water through breathing, sweating, and urine, even in cold conditions.
To confuse thirst with hunger
Another common mistake is to confuse the feeling of thirst with that of hunger. In cold climates, it is common to look for comforting and caloric foods, which can lead to excessive calorie consumption when, in reality, the body only needs liquids. This confusion can be harmful for those seeking to maintain a healthy weight or improve their sports performance.
To avoid this mistake, it is useful to drink a glass of water before eating when you are hungry. If the feeling of hunger persists after a few minutes, you are more likely to really need food. This practice not only helps maintain adequate hydration, but can also contribute to better weight management.
Excessive use of caffeine-containing beverages
In cold climates, it is tempting to consume hot drinks such as coffee or tea to stay warm. However, excessive consumption of caffeine can have a diuretic effect, increasing urine production and hence fluid loss. This can lead to inadvertent dehydration if not compensated with enough water.
In short, avoiding these common mistakes is key to maintaining adequate hydration in cold climates. Being aware of the need for water, differentiate between thirst and hunger, and moderate caffeine consumption, you can optimize your performance and well-being during exercise in cold conditions.
Additional tips for athletes
Maintaining proper hydration in cold climates is crucial for sports performance.
Suitable clothing to minimize water loss
Choosing the right clothes is essential to control water loss through perspiration. In cold climates, it is common to underestimate the amount of sweat that occurs, as the thermal sensation can be misleading. Opt for clothes that offer good breathability and at the same time keep you warm. Layers are an excellent strategy:
- Base layer: Use moisture absorbing materials, such as polyester or merin wool, to keep your skin dry.
- Intermediate layer: A polar lining can provide additional insulation without retaining sweat.
- External layer: A windbreaker or waterproof jacket will protect you from external elements, maintaining body heat.
Foods rich in water to complement hydration
In addition to drinking liquids, eating high-water foods can be an effective strategy to keep you hydrated. These foods not only contribute to total water intake, but also provide essential nutrients that can improve your performance. Examples include:
- Fruit: Watermelon, melon, oranges and strawberries are excellent options.
- Vegetables: Cucumbers, lettuce, celery and tomatoes are rich in water and easy to incorporate in salads or as snacks.
- Soup and broth: They are ideal in cold climates, offering both hydration and calories necessary for exercise.
Monitoring of signs of dehydration
In cold climates, signs of dehydration may be less evident than in warm climates, but not less important. It is crucial to be attentive to the signs that your body sends you:
- Dark urine: A dark color and a lower urination frequency are indicative of dehydration.
- Inexplicable fatigue: Feeling more tired than usual can be a sign that you need more fluids.
- Dizziness or confusion: These are more serious signs of dehydration and require immediate attention.
Therefore, we encourage you to customize these tips according to your specific needs and the conditions of your training environment. Remember that good hydration is the basis for optimal performance, even in colder climates.
Why the cold deceives thirst
Two mechanisms explain why it is easy to dehydrate in winter:
- Less thirst: with cold, the feeling of thirst may be lower for the same degree of dehydration (Kenefick et al., 2004).
- More urine: Peripheral cold vasoconstriction increases diuresis (Castellani and Young, 2016).
If you also train very warm, you can sweat quite without noticing it. Think before and after a long session with cold and write down how much you have drunk: so you will know how much you lose in those conditions.
«In winter the athlete comes home saying that he has not drunk because he was not thirsty. That's why in cold long runs I ask you to bring warm drink and drink with plan, not just when you feel like it." — Marc Bañuls, coach with more than 15 years of experience
Frequently Asked Questions
Do you have to drink less when it's cold?
Not necessarily. You sweat less visibly, but you're still losing fluid and you're less thirsty. Drink with plan in the long sessions.
How do I know how much liquid I lose in cold training?
Get dressed before and after the session, without wet clothes, and add up whatever you've been drinking. The difference is about your loss of sweat.
How much water should I drink before training?
The amount of water you should consume before training in cold climates can vary depending on several factors, such as your body weight, the intensity of exercise, and the duration of activity. As a reference, ACSM proposes about 5–7 ml per kg weight at least 4 hours before if you are not well hydrated (Sawka et al., 2007). This allows the body to properly absorb the fluid and helps prevent dehydration during physical activity.
It is important to remember that in cold climates, the feeling of thirst may decrease, which could lead to underestimation of the need for hydration. Therefore, it is advisable to establish a hydration routine prior to exercise, regardless of the sensation of thirst.
Is it necessary to drink water if I'm not thirsty?
Yeah, it's essential to drink water even if you don't feel thirsty. In cold climates, the body may not send signs of thirst as clear as in warm climates, which can lead to inadvertent dehydration. Dehydration can negatively affect physical and cognitive performance, making it crucial to maintain regular fluid intake.
How does altitude affect hydration?
The altitude can have a significant impact on hydration. At higher altitude, the air is drier and the breathing rate increases, which can lead to faster fluid loss through breathing. In addition, altitude may increase diuresis, i.e. urine production, which also contributes to fluid loss.
For athletes who train or compete at high altitudes, it is crucial to increase fluid intake to compensate for these additional losses. Monitoring of urine is recommended: a light color indicates good hydration, while a dark color may be a sign of dehydration.
This not only optimizes performance, but also protects the overall health of the athlete.
Read also
Sources
- American College of Sports Medicine; Sawka MN, et al. Exercise and fluid replacement (position stand). Med Sci Sports Exerc. 2007;39(2):377-90.
- Kenefick RW, Hazzard MP, Mahood NV, Castellani JW. Thirst sensations and AVP responses at rest and during exercise-collect exposure. Med Sci Sports Exerc. 2004;36(9):1528-34.
- Castellani JW, Young AJ. Human physiological responses to cold exposure: acute responses and acclimatization to prolonged exposure. Auton Neurosci. 2016;196:63-74.
- Baker LB. Sweating rate and sweet sodium concentration in athletes: a review of methodology and intra/interindividual variability. Sports Med. 2017;47(Suppl. 1)111-28.
