Lovely ladies, you have given me some good laughs (Canadiangran - some terrible images sprang to mind ....!). Also thank you all for the suggestions.
Regarding diet, I eat very little meat, except chicken, usually with some form of salad, and very little bread, all in the cause of a less than successful attempt to lose a bit of weight. I only have soya milk in tea, though do eat quite a lot of yoghurt. I have to confess to ignorance about probiotics- are those the little bottles of some sort of milky drink sold in packs in the supermarket?
The trip is actually a motorcycle jolly we're off on. Riding up this Monday and staying overnight, for an early start the next day, for a day on the track. Then staying overnight again after the track day, as will be totally cream-crackered after that.
So unfortunately do have to wear tight trousers as the leathers are a tad tight (hence the diet). I suspect the first night is likely to be the worse, gale-wise, as I've never done this sort of training day before and mixed feelings of excitement and anxiety may fuel the storm!
My friend has a very good sense of humour so I'm just going to confess and make my excuses in advance, (and offer her ear plugs) though will also go down the chemists in a mo for charcoal/Windeze tablets. I'm not on any meds so no worries about them clashing with the charcoal. Getting it all out in the open beforehand so to speak will at least remove that particular bit of stress.
I suppose it might possibly be to my advantage in helping propel my bike round the track a bit quicker! ??