Teacher in slimming class did explain why; it's all to do with dietary thermogenics. But for some reason I struggle to make sense of metabolic rate so I just pay attention to what I have to do not why.
Little things like walking around while making a phone call can all help to increase your metabolic rate and thus the speed at which you can use calories and I put that into practice this afternoon.
I was making brownies and had to beat the eggs and sugar together for 10 minutes so, accompanied by Tom Jones, I strutted my stuff around my mixing bowl. If you want my body and you think I'm sexy makes very good beating music. Honky Tonk Woman is pretty good too.
It's a good job the hedge outside the kitchen window has grown again.