At work I often spend my lunch break inside a large walk-in refrigerator at 3 or 4 degrees (celcius) - not everyone’s cup of tea, but I like it. One day I wondered how this affects my core body temperature.

If I stayed in the fridge long enough, my body temperature would eventually fall. However, the fact that I don’t even start shivering suggested little or no drop in temperature. I recorded my body temperature over several weeks, and the results surprised me:

Mid morning: 36.4
Before fridge: 36.2
After fridge: 36.9
Mid afternoon: 36.1

The slight decrease through the day was contradicted by an average 0.7 degree rise during the half hour spent in the fridge. Actual temperatures varied slightly from day to day, but warming of my body while refrigerated remained consistent.

Why? I’m active in the hours before lunch, then I sit passively in a deck chair during lunch. I thought the reduced activity would have slowed my metabolism, even if the cold didn’t.
Something is stimulating my core body temperature. Is it the cold that boosts temperature in the core parts by transferring blood away from my chilled extremities? Is it the eating of lunch that boosts my metabolism, like throwing another log on the fire? Or is it both, and if so, which has most influence?

Further measurements - with and without eating, and in and out of the fridge - are on the agenda. Having come this far I feel compelled to uncover the full truth.