Exercising in hot weather is part of life in south-east Queensland from October to March. You do not need to stop training in summer, but you do need to change how you train. These are the rules we use at our Samford gym and on our outdoor sessions.
What heat does to a session
In the heat, your body sends more blood to the skin to shed warmth. That leaves less for working muscles, so the same pace feels harder and your heart rate climbs higher than usual.
That is normal. The mistake is trying to hit winter paces in January.
Rules for exercising in hot weather
- Move the session. Before 7am or after 6pm beats the middle of the day by a long way.
- Train by effort, not pace. Expect to be 15 to 45 seconds per kilometre slower on hot mornings.
- Shorten the hard work. Cut interval lengths, add recovery between reps, or move them indoors.
- Find shade. Bush tracks and tree-lined streets can be several degrees cooler than open roads.
- Dress for it. Light, loose, light-coloured clothing, a cap and sunscreen.
- Drink to a plan. Start with fluid on board and carry water for anything over 45 minutes.
Acclimatise over two weeks
Your body adapts to heat over roughly 10 to 14 days of regular exposure. Early in the season, keep sessions shorter and easier, then build. People who travel from a cooler climate need the same lead-in.
What goes in your bottle
For most sessions under an hour, plain water is enough. For long, very sweaty sessions, many people add salt and carbohydrate. Our electrolyte drinks guide covers when that is worth it.
Whatever you add, read the label first and check it is made for people to drink. That sounds obvious, but some products on the shelf are not. You may see fulvic and humic products in both health food stores and garden centres, for example, and they are very different things. This page on fulvic and humic explains how to tell a food from a soil product.
Warning signs to stop
Stop, find shade and cool down if you notice any of these:
- Dizziness, light-headedness or nausea
- Goosebumps or chills in the heat
- Confusion or clumsiness
- A heart rate that will not come down when you slow
- Stopping sweating on a hot day
Confusion or collapse is a medical emergency. Call 000.
Swap the session when it is too hot
Some days are simply not worth it outdoors. Swap a hard run for a strength session in an air-conditioned gym. Our running plan for beginners and senior strength workout both have options that work indoors.
A good running warm-up still matters in summer. You warm up faster in heat, so it can be shorter, but do not skip it.
Common questions
What temperature is too hot to exercise outside?
It depends on humidity, shade and fitness as much as the number. Once it is above the low thirties with high humidity, most people are better off moving the session indoors or to early morning.
Is it good to train in the heat?
Some heat exposure helps you cope with summer events, but it should be built gradually and kept mostly easy.
Should older adults avoid exercising in hot weather?
Not avoid, but be more careful. Train early, keep efforts lower and pay close attention to how you feel.
How much should I drink in hot weather?
More than in winter. Weighing yourself before and after a session is the best guide: each kilogram lost is about a litre of sweat.
When to get it checked
If you have a heart condition, take medicines that affect heart rate or fluid balance, or have felt unwell in the heat before, see your GP and an exercise physiologist before summer training.