Last year sometime there was a thread posted about rest stops in order to maximise mileage.
A couple of people suggested 5mins break every hour, with feet elevated (eg on a pack) to drain the bad stuff from feet/legs and allow them to recover fast.
I've tried this a couple of times since then on training days, of about 50km on relatively hilly terrain, 25kg packweight.
It worked better than I thought! For me, leg/muscle pain/fatigue is pretty much non-existant even working that hard (I have built up to it), but foot pain from pounding is the stinker. I found that for my 5mins, I was only really elevating my feet for about 2-3 (taking into account drinking and eating, etc), but that was perfect. A couple of times later in the day I elevated for longer-about 10, but this was a bad idea, as it drained too much blood from my feet (which had of course swelled abit over the day), allowing them movement inside my runners, which was starting to cause blisters.
If foot pain is causing you difficulties in maintaining distance, a regime like this may work well, especially if you get into the routine and force yourself to keep eating every hour, etc.
Taking 5mins everyhour was worth it in terms of overall pace (I was doing 6-7kph walking flat out on flat/downhill, and 3-5kph uphills) allowing me to do 50kms in 10hours without any hassles, and also left me feeling pretty good at the end of the day so I could continually repeat the efforts.
Im not sure how to approach this at the coming State Rogaine Championships (24hr)...we usually dont have a single break for about the first 7 or 8 hours. But the start time is 4pm this year, so we might start implementing the 5min/hr thing as soon as its dark two hours into it (navigation/performance drops at night anyway, so we may aswell conserve energy for the daylight hours the next day). Terrain will be very rugged and rough with plenty of harsh rocks and scrub, no tracks this year, but we will hopefully still do 90-100km.
Hope this helps.