I'm facing a long run, an ultra, that I'm pretty sure I can't do without walking. I can and will try to practice doing it at least once, but I don't really know how to best use walking breaks or how they work.
What strategy works?
And why does it work? Does it help control overheating? Maybe helps remove waste from the muscles? Allows time to burn more fat? I know I'm reaching here.
------After ultra run-------------------
I didnt practice any run/walk methods, and let my weekly mileage drop to 20-30 3 weeks too early. I used Galloway's 5 minute run to 30 second walk ratio and kept in mind how it changed (referring to his book) for slower paces. Previous 50k runs last year always resulted in a slow shuffle at about 12 min/mile, but in this 46 mile run I was at 11 min/mile up to 36 miles. The run/walk helped finish the ultra. I'm still no closer to understanding this really, and if asked to run another half mile at the end I might have quit. 100 miles still feels impossible.
Other runners had different methods and results. Many who ran faster ended up spending a lot of time at aid stations and fell way behind. One speedy lady ran the first 20 miles then did a run/walk of 8 min/ 2 min, or at least that was her planned before she disappeared down the trail. Inspiring to watch. The winner according to his Strava data ran much if not all of the course at an unbelievable pace. Most people seemed to shun walking as much as they shunned running fast which was anything faster than 10 min/mile in the first few miles.
Still digesting the one answer here, but maybe the answer is in there.
No way can I do 100 miles sucessfuly the first time without understanding this first, but maybe failure is worth the lessons learned...