Science in Scouting; Feeling cold after a dip in the water?

Yeah, so you're in the forest, playing around in the river.

WHOA! SO COLD!!
Ok, so you're shivering. How to heat up yourself?

Well, actually, when you're shivering, your body is just trying to increase muscle activity. The increase of muscle activity generates heat as a byproduct. And this byproduct is what we want to keep ourselves warm. Awh... our body is so cool right?

Hmm... increase in muscle activity eh? So that means if I exercise when I'm feeling cold, I'll feel warm again? Well, it's possible. Since when you exercise, you move your muscles more, releasing more heat. And also, when you exercise, you increase your heart rate. So, the heart can pump the warm blood throughout your body faster. So, the next time you feel cold right after a swim in the Freezing Cold River of Doom *cue dramatic music and lightning*, go do some push up! Lol!

Oh oh, and here's something I saw from Discovery Channel's Man vs Wild show. Oh, that Bear Grylls is a smart guy.

You see, the jungle has no heater or whatever to erm.. heat yourself up. So, the first thing that will come to your mind about warmth in the jungle is campfire right? Well, that's one way.

So, you go start a fire. Then eat a marshmellow or two and don't worry too much about the risk of starting a forest fire (hahaha!). When the fire is big enough, dump some big rocks into the fire. Yes, rocks. You want to heat those rocks up, until they are as hot as the woman in .... ahem... ignore that.

Sooner or later, the fire will "die". Scoop up a big pile of sand and dump it over the campfire just now. Build a thick layer of sand above the campfire. This sand will insulate you.

As you see, when the thickness of the sand is just right, the heat from those rocks will conduct through the sand. But since sand is a poor conductor of heat, the temperature of the thick layer of sand will be just right for you to lie on. And the warmth should be soothing enough. So, you'll have a warm bed to sleep on and recover. And somemore, the rocks can store heat for quite a long time, depending on their mass lah.

Be careful though, you don't want the layer of sand too be too thin. You'll know what will happen right, if you didn't place enough sand. The sand is just to protect you from the extreme heat from the rocks.