By Nutritionist Juliana Ksander.
 

As the summer sun comes out, temperatures rise, and young athletes find themselves on fields, courts, or in swimming pools, the focus on nutrition should also take a front-and-centre role. 

Proper fuelling around training sessions is essential, particularly during the hot summer months.

The Problem with Heat

When training in the heat, the body has to work harder to regulate its temperature, redirecting blood flow to the skin to help cool down, which puts extra strain on the heart and muscles as they try to perform [1]. This extra physiological workload burns more energy than the same session would in cooler conditions, which means summer training days often require more food, even if an athlete’s appetite may not reflect that [1,2].

Fluid losses in the summer and the importance of Hydration and Electrolyte Balance

Summer heat can lead to excessive sweating, which results in the loss of water and electrolytes, particularly sodium, along with smaller amounts of potassium and magnesium [2,3]. Young athletes are generally less efficient at regulating body temperature than adults [3], making them more vulnerable to the effects of dehydration in intense heat. Maintaining hydration is extremely important for preventing heat-related illnesses and ensuring optimal performance. Electrolytes such as sodium, potassium, and magnesium are vital for muscle function and should be replenished through both food and fluids.

Signs of under-hydration to observe:

• Dark yellow urine (pale, light yellow is the target)

• Headaches or dizziness during or after training

• Cramping, especially later in a session

• Fatigue that feels different from normal training tiredness

• Reduced performance despite feeling like effort is the same

For parents: having a drink bottle that gets refilled and finished is a simple thing to check in on during camps or tournament days when routine is less predictable.

Why Hydration and Electrolyte Balance are Extra Important in the Summer

For most day-to-day training, plain water does the job. However, for longer or particularly hot sessions, lasting more than an hour (such as tournaments with multiple games in a day, or back-to-back sessions), electrolytes become essential. Sweat composition refers to the amount of electrolytes lost in sweat [2], and water alone doesn't replace what is lost [3,4]. The more we sweat, the more electrolytes we lose and thus, need to replace. Lost electrolytes can be replaced with an electrolyte drink, higher-sodium foods, and water. If your athlete is a heavy or salty sweater, they may need more electrolytes. 

High electrolyte foods include:

• Pickles — high in sodium

• Salted nuts — High in sodium and magnesium

• Bananas — high in potassium

• Dairy or fortified plant milk — High in calcium

• Tinned tuna — High in magnesium

Recovery food matters even more when sessions are frequent

Training multiple times a day or for several days in a row leaves less time for the body to recover between sessions. Refuelling after training will aid recovery and replenish glycogen stores [5], which are where carbohydrates get stored. This will help with energy levels and prepare your athlete for their next training session. 

A good after-training meal includes a mix of carbohydrates to restock energy stores and protein to support muscle repair [1,4]. Aim for 20-40g protein + 50-60g carbs within 30-60 minutes after a session [5]. 

Good options for refuelling include:

• Pasta with a protein source like chicken, tofu, or mince (check out a high-protein carbonara recipe using tofu)

• Yoghurt with granola and fruit

• Oats mixed with protein powder and fruit

• Eggs with toast

• Rice and Beans with Chicken

Lack of appetite is common after intense training, especially in hot weather, due to increased energy demands [1]. If this becomes an issue, some quick nutrition options, such as YSN’s NUTRI-TEEN shakes, are a great option.

7. A simple summer nutrition plan 

Before training:

• Give your body the nutrition it needs. A larger, balanced meal with protein, high-quality carbohydrates, and moderate healthy fats should be consumed roughly 2-3 hours before training.

• Drink 300–500ml of an electrolyte sports drink 1-2 hours before a session to go in well hydrated.

During training (especially longer or hotter sessions):

• Regular sips of water and electrolytes for sessions over about an hour, or in particularly hot conditions

• A quick-digesting carbohydrate for a session over an hour

• A banana

• YSN’s NUTRI-TEEN Energy Snack Bars

• Dried fruit (Mango, raisins, pineapple)

• Dates

After training:

• Fluids to rehydrate; regular water consumption throughout the day, not just during training, is essential for consistent hydration, energy, and digestion. 

• A meal or snack with both carbohydrate and protein within a 1-2 hours after training

Summary

Heat increases the body's energy and fluid demands when schedules might be the least predictable, which is exactly why a few simple strategies matter more, not less. Nutrition does not need to be complicated: eat consistently, drink consistently, and don't wait until thirst or hunger show steal the show, particularly in hot conditions.

Tips for parents and athletes 

For athletes:

• Drink throughout the day, not just during training

• Check urine colour as a rough hydration guide; aim for pale yellow

• Eat something within a couple of hours after training, every session

• Pack snacks for camps and tournament days so there's always a  quick energy boost

• Don't skip meals just because the schedule is chaotic

For parents:

• Keep easy snacks and a refillable drink bottle part of the regular kit bag

• Build in a proper meal window around tournament and camp days, even if it means packing food

• Watch for signs of under-hydration or fatigue during multi-day events

• Remember, appetite diminishes in the heat, so a light routine of encouraging your athlete to eat helps more than waiting to feel hungry
  
  

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.

References

[1] Bergeron MF, Devore C, Rice SG, et al. Climatic heat stress and exercising children and adolescents. Pediatrics. 2011;128(3):e741–e747. https://doi.org/10.1542/peds.2011-1664

[2] Baker LB, Physiology of sweat gland function: The roles of sweating and sweat composition in human health Temperature: Multidisciplinary Medical Journal. 2019; 6(3), 2011-259. 10.1080/23328940.2019.1632145

[2] Rowland T. Fluid replacement requirements for young athletes. Sports Medicine. 2011;41(4):279–288. https://doi.org/10.2165/11584320-000000000-00000

[3] Nagata, J. M., Vittinghoff, E., Gabriel, K. P. et al. Moderate-to-vigorous intensity physical activity from young adulthood to middle age and metabolic disease: a 30-year population-based cohort study. British Journal of Sports Medicine. 2021 https://doi.org/10.1136/bjsports-2021-104231 

[4] Desbrow B, McCormack J, Burke LM, et al. Sports Dietitians Australia position statement: sports nutrition for the adolescent athlete. International Journal of Sport Nutrition and Exercise Metabolism. 2014;24(5):570–584. https://doi.org/10.1123/ijsnem.2014-0031

[5] Aragon AA, Schoenfeld BJ. Nutrient timing revisited: is there a post-exercise anabolic window? J Int Soc Sports Nutr. 2013 Jan 29;10(1):5. https://pmc.ncbi.nlm.nih.gov/articles/PMC3577439/