On my first hundred, I changed socks and shoes every 25 miles. I'd done a 50 mile event a month before and had a lot of trouble with blisters. I actually went to a chiropodist and she said it was probably the heat that had caused the blisters and suggested changing socks and shoes often to cool them down. Since then, I think I've just changed them twice. Putting on new socks makes the biggest difference, your feet feel really nice - although they soon get wet again, so I'm really not sure it's worth all the trouble of undoing the laces etc. If the hundred were in winter, I think it would be different.

A good question - certainly worth packing a pair in the breakfast bag. However, after a trouble free 60 miles on the Wessex 100 I foolished changed shoes into my spare pair as they were there. Unfortunately they were marginally tighter and gave me a few issues as my feet had swelled. On the HOS I wore just 1 pair. I would suggest only changing if needed (eg discomfort, wet feet), and if there is any difference in fit, keep the larger pair for latter part of the walk. However I would suggest changing your socks every 30 miles or so - not because other walkers will complain, but your feet will sweat and potentially blister, particularly so if you are wearing waterproof shoes

im doing my first 100 this year and my strategy was to wear trail trainers but to change them at the half way mark. the theory is that the new pair will be already worn in but dry and grit free. does anyone else do this ? or has anyone tried it and found little benefit?

cheers
Colin