The intention was to go swimming at Bozel “Beach” (1400m altitude) where the the water was 6 degrees – but unfortunately the lake was half drained due to maintenance and there was only enough water for the ducks. We had to go all the way up to Champagny Le haut at 1560m where the stream water was at 0.5 degrees – seriously cold. I’d been swimming in the lake at Tignes a few days earlier at 1 degree so it wouldn’t be impossible – but fast running mountain water is even harder than swimming in a lake. The idea is to provoke a stress response through the skin – involving adrenaline. This not only adapts the body to the cold but also to stress, pain and a whole host of other positive things including increased sensitivity to insulin. The water has gone cold early this year due to weeks of clear skies allowing all the heat to radiate away from the ground.
Getting ready! Pretending to swim in a rock pool.
Bright lobster red from the cold – doesn’t even feel cold once getting back out. Being already well adapted (down to 8 deg) there is no shivering. The idea of cold thermogenesis is that the heat begins to come from brown fat – directly through the mitochondria and not from mechanical movement (shivering).