Hot Weather Racing

Summer is on the horizon, which means hot weather racing, this is less of an issue for cycling (still an issue) but a bigger issue in running due to slower speeds and less will chill.

For the purpose of this post, it will be focused around ultra running, but most of these tips can be applied to most sports!

Outlaw 2024, daft, but sensible hat on

1. Sodium Pre-Loading

Take ~1000–1500mg supplemented sodium the day before leading up to the race this additional sodium will increase plasma volume and promotes water retention, which can delay dehydration and improve thermoregulation during early stages of the race.

2. Hydration + Electrolyte Strategy

Aim for ~400–800mg sodium/hr depending on your sweat rate and weight. Replace both fluids and electrolytes—don’t rely on water alone. Overhydration without salt risks hyponatremia. Hyponatremia is diluted sodium concentration and can lead to various symptoms, ranging from mild to severe, including muscle cramps, confusion and sickness.

3. Cooling Arm Sleeves

Soak lightweight sleeves at aid stations—they retain moisture for evaporative cooling while protecting from sun exposure. Cooling the skin reduces thermal strain and perceived effort. Pass a stream in the mountains? Put your arms under the water, your arms have a large surface area with blood supply running reasonably close to the skin.

4. Wear a hat

The head accounts for a significant proportion of total body surface area, and in direct sunlight, it’s a major point of heat absorption. A light-colored, breathable hat reflects solar radiation, reducing skin temperature and delaying heat load accumulation.

5. Wear light coloured clothing

Light-coloured clothing generally absorbs less heat than dark coloured clothing, which results in lower skin temperature.

6. Adjust Your Early Effort

In the heat, blood is diverted to skin for cooling—leaving less for working muscles. Go out conservatively to prevent cardiac drift and overheating later in the race.

7. Red Flags

Dizziness, headache, chills, or confusion? Back off and cool down. Heat stroke isn’t worth the finish line.

Top tip: Heat adaptation will help massively with any heat on race day, it’s a good idea to implement this into your training

Got questions about hot weather prep? DM me—happy to help!