Heat changes the ride
Riding in warm weather is one of the pleasures of cycling, but heat adds a load that is easy to underestimate. Your body works to keep cool by sweating, and on a bike you are also making effort, so you can lose fluid faster than you notice. The breeze from moving can make it feel cooler than it is, and the cooling effect disappears the moment you stop or slow on a climb. This article offers general habits. It is not medical advice, and people with health conditions, or who take certain medicines, should ask a doctor about exercising in the heat.
Choose your time and route
The simplest change is often to ride when it is cooler. Early morning and evening are usually more comfortable than midday and the early afternoon, and dusk and dawn riding come with their own considerations, because you need lights and visibility. Consider:
- Shaded roads, tree-lined paths or routes beside water
- Routes with regular places to refill bottles or buy a drink
- Shorter or flatter routes than usual, since hills add heat
- Loops that pass near home, shops or cafes so you can stop easily
Some route planning before you leave means you won’t be stuck in a long exposed stretch with no water. Check the forecast too, including humidity. In very humid conditions sweat evaporates less well, so the same effort can feel much harder, as described in advice about humid weather riding. Places with intense dry heat, such as the desert, bring their own challenges, and desert cycling is its own subject, usually requiring extra planning.
Water and food
Drink regularly from the start of the ride, rather than waiting until you feel very thirsty. Carry more than you think you need, and know where you can top up. Needs vary a lot between people and between days, so there is no universal quantity. Drinking some extra water is not a magic fix, and drinking far too much can also cause problems, so aim for steady sips and listen to your body.
Eat as you normally would on a longer ride. Some riders find drinks with electrolytes helpful, while others are fine with water and food. If you have a medical condition that affects what you should drink or eat, follow your doctor’s guidance. Cold drinks can be pleasant, and an insulated bottle helps keep them cool for longer.
Sun protection and clothing
Light-coloured, breathable, loose or well-ventilated clothing is generally more comfortable in the heat. Cycling kit made for warm weather is designed to move sweat away, but ordinary lightweight clothes work for short rides. Consider:
- Sunscreen on exposed skin, reapplied as the product instructions suggest
- Sunglasses to protect your eyes from glare and dust
- A helmet with good ventilation, fitted correctly
- Light long sleeves, which some riders find protect the arms from sun
Never skip your helmet to feel cooler. Gloves can feel hot but protect your hands if you fall, and many riders prefer them.
Pace yourself
Heat makes the same effort feel harder, so ride more gently than you would on a cool day. Pacing effort is especially important: slow down on climbs, take breaks in the shade, and let the pace drop without feeling guilty. A heart rate or speed that feels normal on a cool day may be too much on a hot one. Skipping a planned distance is better than pushing through.
Be careful about starting out when you are already dehydrated, tired, unwell or have had alcohol the night before. Heat tends to amplify these.
Know the warning signs
Heat illness can become serious, and it can develop quickly. Warning signs include:
- Dizziness, light-headedness or confusion
- Headache or nausea
- Unusual weakness or heavy tiredness
- Cramping
- Skin that is very hot and either dry or clammy, a racing heartbeat, or fainting
If you notice these, stop riding. Find shade, sit or lie down, sip fluids if you are alert, loosen or remove clothing, and cool the skin with water. Ask someone to stay with you. If symptoms are severe, or you are confused or lose consciousness, call emergency services. Don’t try to carry on to finish the ride. Recovering after a bad experience with heat can take time, and a doctor can advise.
Bike and road details
Hot weather affects the bike too. Tyres can get warmer and the pressure can rise, so follow the pressure range printed on the tyre sidewall and avoid overinflating. Hot tarmac can soften and feel slightly different, and brakes on long descents can heat up. Sun cream can make hands slippery on the bars, and sweat can run into your eyes, so a headband or cap under a helmet may help.
Heat can also make drivers and other riders irritable, and it makes everyone less alert, so stay visible and predictable, and keep checking the road ahead.
Be willing to change plans
On extreme days, the safest choice may be not to ride, or to ride indoors or later. Heat warnings from local authorities are worth taking seriously, and extreme weather is rarely the right time to attempt a personal best. Reduce, shorten or reschedule without feeling you’ve failed. There will be other days.