By Performance Nutritionist, Tamara Walker book a 1-2-1 with Tam here



As summer approaches, how can we exercise safely in the heat? 

Training in hot conditions presents both challenges and opportunities for athletes. While heat exposure can enhance endurance and performance over time, it also increases the risk of dehydration, heat exhaustion, and even heatstroke (1). Additionally, understanding thermoregulation, the body's ability to maintain a stable internal temperature, is crucial for safe and effective training in the heat (2). Here’s what athletes need to know about exercising in hot environments and optimising thermoregulation.

How the body regulates temperature...

The body regulates our core temperature through various mechanisms, including sweating, vasodilation, and respiratory heat loss. Sweating is the primary way the body cools down, as sweat evaporating from the skin helps dissipate heat. Vasodilation, or the expansion of blood vessels close to the skin's surface, promotes heat loss, especially during intense exercise. When exercising in high temperatures, these systems work harder, increasing fluid loss and the risk of overheating (3).

Hydration: The Key to Heat Adaptation

Dehydration impairs thermoregulation and athletic performance. Athletes should drink plenty of water before, during, and after exercise. Including electrolyte-rich drinks helps replenish sodium, potassium, and other essential minerals lost through sweat (4). Monitoring urine colour is a simple way to check hydration levels, pale yellow indicates proper hydration, while dark yellow suggests dehydration (5).

Gradual Acclimatisation to Heat

Sudden exposure to high temperatures can be overwhelming. Instead, athletes should gradually increase training intensity and duration over 7–14 days to allow the body to adapt when exercising in hot conditions. Training during cooler times of the day, such as early morning or late evening, can help ease the transition before moving to hotter periods. Adaptation enhances sweat efficiency and cardiovascular function, improving heat tolerance over time (6).

Choosing the Right Gear

Clothing can significantly impact heat management. Wearing light-coloured, loose-fitting, and moisture-wicking fabrics helps the body stay cool. Hats, visors, and sunglasses provide protection against the sun, while sweat-resistant sunscreen prevents sunburn, which can impair thermoregulation (7).

Recognising Warning Signs of Heat Stress

Ignoring warning signs can lead to serious health risks. Athletes should be aware of symptoms such as dizziness, nausea, excessive fatigue, muscle cramps, and excessive sweating followed by little to no sweating. Confusion or disorientation could signal heatstroke, which is a medical emergency (8). If any of these occur, athletes should stop exercising immediately, move to a cooler area, hydrate, and seek medical attention if symptoms persist.

Optimising Nutrition for Heat Performance

Proper nutrition plays a crucial role in heat adaptation and recovery. Eating water-rich foods like fruits and vegetables helps maintain hydration. If sweating excessively, slightly increasing salt intake can prevent electrolyte imbalances. Avoiding an excessive caffeine intake is also essential, as this can further contribute to dehydration (9).

Adjusting Training Strategies

Athletes can make adjustments to their training routines to maintain performance while minimising risks. Reducing intensity and duration when training in extreme heat is crucial (10). Incorporating more breaks and training in shaded areas whenever possible can also help. On especially hot days, cross-training indoors may be a safer alternative.

Effective Cooling Techniques

Cooling down properly can enhance comfort and performance. Taking cool showers or using cold towels before and after workouts can help regulate body temperature. Utilising cooling vests or ice packs on key areas like the neck and wrists provides additional relief. Running water over pulse points is another effective way to lower body temperature quickly (11).

Conclusion

Exercising in the heat requires careful planning, hydration, and body awareness. Understanding thermoregulation can help athletes optimise their performance and reduce the risk of heat-related illnesses. By following these essential tips, athletes can train effectively while maintaining a safe and balanced internal temperature. Always prioritise safety and adjust training routines based on individual tolerance and environmental conditions.

By Performance Nutritionist, Tamara Walker book a 1-2-1 with Tam here

Can Youth Sport Nutrition help?

Youth Sport Nutrition products comprise of whole food ingredients that have been carefully selected to aid young athlete’s needs, taste great and add convenience to a busy schedules. The powdered formulas enable quick solubility in water or milk, to form a delicious nutrient packed shake that your youth athlete can enjoyed pre or post exercise- helping aid recovery and increase energy.

Youth Sport Nutrition always recommend to opt for whole foods first as the rule. Food powders such as NUTRI-TEEN shakes, and Oat energy bars are a nutritious way to top-up on high-quality nutrients to support parents of youth athletes faced with tight schedules. 

If you want any help with designing a food-first meal plan, you can speak to our nutrition team today.

References

(1) Solomon, T. P. J., & Laye, M. J. (2025). The effect of post-exercise heat exposure (passive heat acclimation) on endurance exercise performance: a systematic review and meta-analysis. BMC sports science, medicine & rehabilitation, 17(1), 4. https://doi.org/10.1186/s13102-024-01038-6

(2) Damatto, R. L., Cezar, M. D. M., & Santos, P. P. D. (2019). Control of Body Temperature during Physical Exercise. Arquivos brasileiros de cardiologia, 112(5), 543–544. https://doi.org/10.5935/abc.20190081

(3) Baker L. B. (2019). Physiology of sweat gland function: The roles of sweating and sweat composition in human health. Temperature (Austin, Tex.), 6(3), 211–259. https://doi.org/10.1080/23328940.2019.1632145

(4) Maughan, R. J., & Shirreffs, S. M. (1997). Recovery from prolonged exercise: restoration of water and electrolyte balance. Journal of sports sciences, 15(3), 297–303. https://doi.org/10.1080/026404197367308

(5) Kostelnik, S. B., Davy, K. P., Hedrick, V. E., Thomas, D. T., & Davy, B. M. (2021). The Validity of Urine Color as a Hydration Biomarker within the General Adult Population and Athletes: A Systematic Review. Journal of the American College of Nutrition, 40(2), 172–179. https://doi.org/10.1080/07315724.2020.1750073

(6) Pryor, J. L., Johnson, E. C., Roberts, W. O., & Pryor, R. R. (2018). Application of evidence-based recommendations for heat acclimation: Individual and team sport perspectives. Temperature (Austin, Tex.), 6(1), 37–49. https://doi.org/10.1080/23328940.2018.1516537

(7) Périard, J. D., Eijsvogels, T. M. H., & Daanen, H. A. M. (2021). Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiological reviews, 101(4), 1873–1979. https://doi.org/10.1152/physrev.00038.2020

(8) Wendt, D., van Loon, L.J. & Marken Lichtenbelt, W.D. Thermoregulation during Exercise in the Heat. Sports Med 37, 669–682 (2007). https://doi.org/10.2165/00007256-200737080-00002

(9) Di Domenico, I., Hoffmann, S.M. & Collins, P.K. The Role of Sports Clothing in Thermoregulation, Comfort, and Performance During Exercise in the Heat: A Narrative Review. Sports Med - Open 8, 58 (2022). https://doi.org/10.1186/s40798-022-00449-4

(10) Gibson, O. R., James, C. A., Mee, J. A., Willmott, A. G. B., Turner, G., Hayes, M., & Maxwell, N. S. (2019). Heat alleviation strategies for athletic performance: A review and practitioner guidelines. Temperature (Austin, Tex.), 7(1), 3–36. https://doi.org/10.1080/23328940.2019.1666624

(11) Bongers, C. C., Hopman, M. T., & Eijsvogels, T. M. (2017). Cooling interventions for athletes: An overview of effectiveness, physiological mechanisms, and practical considerations. Temperature (Austin, Tex.), 4(1), 60–78. https://doi.org/10.1080/23328940.2016.1277003

Disclaimer: This article is intended to provide general information about nutrition for youth athletes and is not meant to replace professional dietary advice or individual nutritional counselling. Every child's nutritional needs can vary due to factors such as age, size, physical activity level, and medical conditions. We strongly recommend consulting with a registered dietitian or a healthcare provider before making changes to your child's diet, such as adding food powders. YSN and the author of this article do not take responsibility for any possible consequences from any treatment, procedure, dietary modification, action, or application of medication which results from reading or following the information contained in this article.