Cycling in the Melbourne heat

Be alert to the symptoms of heat exhaustion

The Breakaway

Being in the hot Melbournian summer means that cyclists need to be wary of heat exhaustion and stroke.

The Leadout

Eighteen months ago I had a reminder of just how easily this can happen, on the ride home from the MS Melbourne Cycle. Despite taking precautions, I was ‘cooked’ about 20 minutes from home on the return leg. It happened very quickly and ruined an otherwise very enjoyable event.

Shameless plug: you can find the MS Melbourne Cycle at: http://www.msmelbournecycle.org.au/default.asp

The Peloton

So lets start with the basics c/o St John’s First Aid -> http://www.stjohnnsw.com.au/heat-induced-conditions/w1/i1035112/

What is it?
Heat exhaustion results from a decrease in blood pressure and blood volume. This is due to the loss of fluids and electrolytes when exposed to the heat for a prolonged period of time.

How to do know you’ve got it?
As well as general fatigue, symptoms include, feeling sick, faint and heavy sweating. The skin will be flushed and hot to the touch, heart rate elevated and the rider may also complain of feeling dizzy and appear confused. I can vouch for this and general feeling of being really unwell.

What do you do about it?
Any rider displaying these symptoms should stop cycling immediately and find somewhere cool and in the shade. They should be given fluids to sip, ideally water or a sports drink, and may be cooled with a wet flannel or light spraying with cool but not cold water. They should recover within 30 minutes but, if they are still displaying symptoms after this time, contact the emergency services.

What happens if you ignore the symptoms and press on?
If the symptoms of heat exhaustion are ignored and the rider continues to push themselves, exertional heat stroke, where the body temperature rises to dangerous levels, can occur. Then some serious adverse effects may kick-in:

  • Heavy sweating will suddenly stop, the riders skin will feel cold and clammy and they may complain of feeling cold despite the heat.
  • Heart rate and breathing will be significantly increased and they may also be suffering from muscle cramps.
  • They may vomit, complain of having a headache and be confused and disorientated.
  • In severe cases, fitting and a loss of consciousness may occur.

What’s the treatment for severe heat stroke?
The priorities are to get the rider out of the sun and to contact the emergency services. While waiting for them to arrive, if conscious, the rider should be given fluids to sip and can also be cooled with a damp flannel or spraying. Avoid complete immersion in cool water and do not give any form of medication. If unconscious, place them into the recovery position.