[Narsil]

I used to effectively fast for about 5-6 hours before serious apnea (either competition or hard training).

I now make sure I eat something readily digestable, such as a banana, abount an hour - 90 minutes prior. I find there's little downside. It helps keep my bloodsugar in balence, which in turn reduces the risk of packing black outs.

When I'm out spearfishing I often eat quite a lot just prior to diving, and if in a boat, I'll eat say halfway through a 4-5 hour spearfishing session.

It's all personal though - some people don't have the type of constitution or metabolism for this to work at all.

Guy