Watty says:

Ah, that endorphin high - I'd forgotten how powerful it coud be. The class was just about right - no specific aches and pains this morning, just a feeling of having been thoroughly worked out. I'm greatly encouraged by the lack of pain, incidentally - I went to bed last night with a decidedly stiff calf (be quiet at the back) but am walking freely this morning, much to my delight. So, the consensus is - I'll definitely be doing that again; hugely enjoyable and good for me; can't say that about too many things...

Pink Grapefruit this morning - still no caffeine, still no side-effects. And the blood I donate later will be uncontaminated by poisonous chemicals (bacon rolls don't have any dangerous things in them, do they?)