It gets hot in summer. From mid May until mid September you can expect a Friday ride to be finishing at temperatures of 38, 39, 40, 41... degrees Celsius. The Friday Rides roll out at dawn when a comparatively pleasant 33-34 degrees is compromised by oppressive humidity. A few hours later that has burned off, the wind gets up and now you are riding in a fan oven. Why do we do it? We love cycling more than we hate summer!
This table illustrates the combined effect of air temperature and humidity. The orange part is coded as "Serious danger: stop all physical activities" but that is the zone we reach at the height of summer. The table isn't cycling specific, so what might appear impossible becomes bearable with the airflow over a moving cyclist. But still, make no mistake that you are attempting something challenging. If this all sounds a little melodramatic, it is because the purpose of this page is prepare you to cope with summer safely. We've seen those who have pushed heat exhaustion far too close to heat stroke. Don't let that be you.
- Ride early or late: Our rides leave at dawn (bring lights) but others start even earlier
- Ride slower or shorter: Realise that not everyone suffers to the same extent. You may need to slow down (more on this below)
- Cooling vests are effective in dry heat but ineffective in high humidity when they act as a layer of insulation.
- Thin arm covers also aid evaporative cooling in dry heat if you soak them. Blocking the sun's radiation also helps.
- Ensure the rack is mounted on the support car at the start of the ride. It is not unusual for 2 or 3 people to need the AC
- Ride indoors. Many cannot cope and retreat to the indoor trainer for the summer
You don't need to be told to drink. Here are some hydration tips:
- Freeze bottles: They won't stay frozen long but the melt rate keeps pace with your need to drink something cold
- Use the insulated bottles that you can buy in most sports stores
- Put extra water in the support car and ensure your group appoints someone to provide a cool box and ice
- When you run out - refill. Don't make the mistake of thinking, "It's only 5km back, it's not worth stopping now"
- Fill one bottle with plain water. You don't want to tip sports drink over your head!
- Cooling your core by eating a slushy at the rest stop can be beneficial if you can handle the brain freeze!
Use of electrolytes
Drinking a lot of water can lead to salt depletion and even serious conditions such as hyponatremia. While it is outwith the scope of this article to make recommendations on the use of electrolyte supplements, there are some tips which can be given here:
- This Aspetar article gives some practical advice and recommends the use of electrolytes based on sweat rate
- Sports drinks containing electrolytes and electrolyte tablets can only be obtained via mail order. Some riders make their own using table salt or oral rehydration salts obtained from pharmacies. As these are a medical product, read the usage instructions carefully. The internet has many recipes for DIY sports drink.
Do not over exert
Summer is not the time for hard riding outdoors. At dawn there may be a temptation to push it but you'll cope with the hottest part of the ride less well if fatigued.
- Realise that heat elevates heart rate. What might feel easy produces a much higher heart rate response which more accurately reflects the physical toll.
- Use a heart rate monitor to stop you going too hard and learn your limit. If taking a turn on the front of the group and your heart rate indicates you are working too hard, it is time to switch to the back. If you don't already use HR during training it may take a few rides to learn what your HR limit should be.
- Use a heart rate monitor to diagnose when its time to quit (see below)
- Acclimatise. It takes a week of regular outdoor riding to build resistance but the gains are lost quickly, so after a holiday you may find yourself struggling again
- Drop to a slower group. Average speeds of the Friday rides won't change much in summer so those who are less heat adapted, or cope less well, often ride with a slower group
Recognise heat exhaustion
Everyone will experience some degree of heat stress. It is important to recognise when the level of stress is starting to become dangerous:
- Elevated heart rate which does not come down with reduction in effort
- A strong desire to no longer be exposed to the sun
- Physical signs may include cramps and no longer sweating
- Lapses of concentration and poor decision making
- Look for signs that your fellow riders are struggling and support them
This advice is written from personal experience plus tips from experienced summer riders but it is not that of a medical professional. As everyone copes with the summer heat differently, it is important that you devise your own strategies and do what works for you.