Performance in Temperature: How Physical Operations Vary in Different Settings

Performance in Temperature: How Physical Operations Vary in Different Settings

Colder Temperatures

Metabolic Changes:

• Exposure to colder temperatures, around 10-16˚C (50-60˚F) increases metabolic rate due to shivering and thermoregulation demands as your body works to regulate its temperature in an cooler outside environment. As metabolic rate increases, more energy - from food and water - is expended/used, meaning that many athletes may require more carbohydrates and calories to sustain peak performance.
  • One solution to making sure energy is sustained is by layering clothing—such as jackets, gloves, and thermal pants—to help maintain a stable core body temperature. Layering traps body heat and prevents excessive energy loss or shivering, allowing muscles to stay warm and reducing the risk of stiffness or injury. 
  • Eating warmer foods in colder temperatures, like soup 1–2 hours before a race, can help maintain core body temperature and reduce the onset of shivering. A heated, carbohydrate-rich meal not only provides quick energy but also supports thermogenesis, making it easier for the body to focus energy on performance rather than temperature regulation. 

Hydration Risks:

• Cold weather can blunt thirst cues—making individuals feel less inclined to drink water. Because the mouth usually does not feel dry and the physical signs of dehydration are less noticeable in cooler temperatures, athletes may underestimate their hydration needs. The risk of dehydration remains significant in cooler weather due to continued fluid loss through respiration, sweat, and other metabolic processes—even if it is less noticeable.
  • Proactive hydration—drinking water consistently throughout the day rather than waiting 30 minutes before or during exercise—can significantly support an athlete’s performance in cooler temperatures by maintaining optimal blood flow, regulating internal body temperature, and preventing the hidden effects of dehydration that often go unnoticed in the cold.

Injury Risks:

• In colder environments, muscles are often found to be stiff and more prone to injury, especially as the body prioritizes maintaining core temperature, which can lead to reduced blood flow to the extremities, especially muscles. This can cause muscles to become stiff and less flexible, making them more prone to strains, tears, or pulls during physical activity. The reduced elasticity and flexibility can increase the likelihood of muscle strains or tears during explosive movements like sprints or jumps.

• As the body attempts to keep warm in cooler environments, shivering may occur, causing involuntary muscle contractions. Although shivering helps generate heat, the energy it uses can also cause muscle fatigue and reduce the efficiency of muscle contractions, making the muscles more prone to strain or injury.

  • Proper Warm-Up: Ensure a comprehensive warm-up that includes dynamic stretches, light jogging, and joint mobility exercises to prepare the body for the physical demands of exercise. Consider starting with a few minutes of light activity in a sheltered, warmer area if possible.

  • Layering Clothing: Wear appropriate clothing layers to keep muscles warm. This includes moisture-wicking materials, thermal clothing, and insulating layers like gloves, hats, and socks to prevent heat loss. Thermal gear can help maintain core body temperature and reduce the risk of stiffness or injury.

  • Gradual Intensity: Start workouts or exercises at a lower intensity to allow muscles to gradually adjust to movement. Avoid jumping into intense physical activity immediately in cold environments.

  • Stay Hydrated: While cold temperatures may not make you feel thirsty, dehydration can still occur. Maintain hydration levels by drinking water or sports drinks regularly to ensure proper circulation and muscle function.

  • Proper Footwear: Wear non-slip footwear with adequate insulation to prevent slips, falls, and cold-induced muscle injuries, especially if you're training outdoors on snow or ice.

  • Monitor Your Body: Be mindful of early signs of shivering, fatigue, or joint pain, which could indicate the body is struggling to adapt to the cold. Take regular breaks, and if conditions worsen, seek shelter and warmth. 

    
    

Hotter Temperatures

Core Temperature and Performance

• Hot environments elevate core body temperature quickly as the body works - using water, energy, etc. - to cool itself down, which can reduce endurance performance due to early fatigue, dehydration, and overheating.
  
  •  A ~1°C rise in core body temperature before exercising in the heat significantly reduced endurance performance in the morning but not in the evening. This means that even a small increase in internal body temp—like from staying out in the sun, warming up too aggressively, or wearing too many layers—can cause fatigue to set in earlier during workouts or competitions if they’re in the morning. 
  • Don’t sit in the sun, wear thick layers, or take hot showers right before morning practice or races. Consistent exposure to these condtitions increases core temperature, makes it harder to cool off before a practice/performance, and does not work your muscles in the direct way a warm-up lap or dynamic exercises would.
    
  • Use a cold towel on your neck, drink icy water, or stay in air-conditioned spaces close to the time of warm-up. Maintaining a cooler body will decrease core temperature and allow you to operate at your best.
  • A cold, carb-rich snack (like fruit, oatmeal, or toast) can support energy without warming your core further.  When you eat before a workout, your body begins digesting food—this process raises your internal body temperature, especially with large or heavy meals. Choosing to avoid adding extra heat from digestion by comsuming foods with less required digestion will help.
    
    Drink cool water or an electrolyte drink in small sips starting 1–2 hours before exercise. Hydration will allow your body to cool itself down

Hydration:

• Increased Sweat Loss
  • Study: Cheuvront & Kenefick (2014) found that in hot environments, sweat rates can exceed 1–2.5 liters/hour, even in moderate activity.
  • Athletes lose fluids faster than they can drink, especially during high-intensity or prolonged exercise, increasing risk of dehydration, especially if pre-exercise hydration is poor.
•  Delayed Thirst Response
  • Study: Sawka et al. (2007) observed that the body's thirst mechanism lags behind actual fluid loss in the heat.
  • Athletes often underestimate how much water they need and don’t feel thirsty until they’re already dehydrated by 1–2% of body weight.
• Cognitive Performance:
  • Extreme heat and cold can stress the body and distract the mind, while moderate temperatures allow for clearer thinking and better concentration during exercise or competition.
•  Performance Drops with Mild Dehydration
  • Study: Casa et al. (2010) found that just 2% dehydration can impair endurance performance, increase perceived effort, and elevate core temperature.
  • Even mild dehydration leads to early fatigue, slower running times, and increased risk of heat illness.
•  Electrolyte Imbalance Risks
  • Study: Bergeron et al. (2005) studied youth athletes and noted that excessive sweating in hot, humid environments without electrolyte replacement led to muscle cramps and performance decline.
  • Water alone may never be enough—sodium and potassium, common electrolytes, must be replenished, especially during longer sessions or repeated training days.
    • Prehydrate: Start hydrating the night before and drink 16–20 oz of fluid 1–2 hours before exercise in heat.
    • Drink during workouts: Aim for 6–8 oz every 15–20 minutes, or more if sweat rate is high.
    • Use electrolytes: Choose a sports drink or add salt to water during long/hot sessions.
      
    • Monitor urine color: Pale yellow = hydrated. Dark = drink more water.
    • Cool your fluids: Cold drinks are absorbed faster and help reduce core temperature.

Indoor Training and Dry Atmospheres

Humidity:

• Performance Optimization: Training and competing in environments with lower humidity has been proven, by multiple studies, to help maintain endurance performance, especially in hot conditions.​
• Thermoregulation: Lower humidity facilitates more effective sweat evaporation, meaning that the sweat used to cool the body down evaporated effectively, aiding the regulation of body temperature regulation during exercise.​
• A study by Cheuvront et al. (2008) found that fluid loss in low-humidity environments (20-30%) could still lead to significant dehydration, particularly in endurance events. Despite better evaporative cooling in these conditions, the performances of athletes who didn’t consistently rehydrate with fluids were impared due to early fatigue and reduced performance.
  • Hydration Strategies: Even in low-humidity environments, athletes should monitor hydration levels, as sweat evaporation can lead to significant fluid loss without the sensation of being overly sweaty.​ Consuming 16-20oz of water 2-3 hours before an exercise/training session can ensure proper hydration
  • Electrolyte Drinks: In dry environments, athletes sweat out important electrolytes (sodium, potassium, magnesium). Drinking sports drinks containing electrolytes or using electrolyte tablets can help maintain fluid balance, prevent cramping, and avoid fatigue.
  • Post-Exercise Hydration: After exercise, it's important to rehydrate with both water and electrolytes to replenish the fluids lost during the workout. Drinking water or electrolyte drinks within the first 30 minutes after exercise can enhance recovery.
  • Carbohydrate-Rich Foods: For long training sessions or races, athletes should consume carbohydrates before and during exercise to help maintain energy levels and support hydration. Foods like bananas, energy gels, or sports bars are great options.

Moderate Temperature

In moderate temperatures (typically ranging from around 18-24°C or 64-75°F), athletes face fewer challenges compared to exreme hot or cold environments; however, there are still key considerations that can affect hydration, energy expenditure, and overall performance.

Key Strategies for Athletes in Moderate Temperatures:

• Routine Hydration: Hydrate CONSISTENTLY throughout the day and drink small sips of water or electrolyte drinks during long workouts.
• Energy-Dense Foods: Eat a well-balanced pre-workout meal that includes carbohydrates and protein to fuel exercise, and consume post-workout recovery meals to restore energy.
• Layering Clothing: Dress in light, moisture-wicking fabrics to stay comfortable and help with sweat evaporation.
• Warm-Up and Cool-Down: Perform dynamic warm-ups to prepare muscles and cool-down stretches to improve recovery without overexerting.
• Listen to Your Body: In moderate conditions, athletes can perform at a high level of exertion for extended periods, but it is important to still monitor for signs of dehydration or fatigue, particularly on longer training days or events.