Cooking from the inside

As temperatures soar in Melbourne the dangers of exercising in extreme conditions have been highlighted at the tennis. But what is all the fuss actually about?

When we exercise our muscles burn energy with heat the natural byproduct.  The more you exercise, the higher your body temperature gets, with up to 4 or 5 degrees added to our usual 36 degrees. 

Our bodies don’t like cooking from the inside, so we need to lose this heat.  Blood is diverted closer to the skin and we sweat.  In the majority of situations heat loss is efficient with body temperature only rising a little bit, and certainly safely.

If the outside temperature is too hot or we have too many layers of clothing on, the body will struggle, and you’ll start to cook. In this situation you will experience the signs of heat exhaustion:
  • Rapid pulse
  • Dizziness
  • Feeling unwell
  • Headache

The extra sweating, jump in breathing and demands of working muscles, uses more water, so we start to dehydrate, which exacerbates this whole heat control business, bringing heat exhaustion on faster. Not eating then exacerbates things further. Think of a night at the pub without anything to eat and no water on board.

Can I get used to it?

The natural body process of heat control needs some training and fine tuning, which is why you hear of athletes “acclimatising” to the heat. When I was in Afghanistan with the Army, I learned how effectively our body can acclimatise if you take things slowly.  Temperatures soared to 48 degrees most days, dropping to a lowly 28 degrees at night.  Yet over a course of two weeks I was able to get out and run for an hour with minimal performance effects.  But if you jump straight into it, or temperatures climb uncharacteristically like in Melbourne, our body suffers with heat exhaustion, which can push to the most dangerous condition called heat stroke.

What should you do?

In my last post I sprouted that drinking is absolutely fine as long as you drink less than your doctor.  Well, when it comes to exercise, a similar philosophy could also apply: don’t do what I do!  I’m bloody stupid in summer – the suns out, the kids occupied, it’s Saturday afternoon, and I need to burn some energy: so I smash the gym or head out for a hard and fast run on the coast.

Idiot!  Because I try and do it in the hottest part of the day when I’m not acclimatised.

  • Exercise when its cool (early in the day) or head to a cool gym.
  • Drink extra water. A good swig every 15-20 minutes is important.  In fact you can monitor your water loss by weighing yourself before and after your session, and try and replace it in the first couple hours after you train.  salt and sugar helps you absorb the water better so have something to eat or a sports drink to really get that rehydration boost.
  • If you have to exercise when it’s hot,think about shorter bursts with lower intensity.
  • Listen to your body – if you’re experiencing the early signs of heat exhaustion STOP!  Take a rest, cool down, have a drink, then either quit or push off again if you’re feeling fine..

Now get out there, but don’t be an idiot!