I was thinking about the racing flat thread today during my 5 mile run. The arguments were being made that less shoe was better for anatomical reasons. I began wondering if there is a benefit from lifting less weight (shoe). I did some math when I got back and these are the numbers I came up with. My current shoe, Brooks Beast weighs 15.2 oz. I found the weight of a racing flat online that said it was 7 oz. So lets say 7 oz difference between my shoe and a flat. Take that times 70 strikes a minute (est cadence) times 270 minutes (est marathon split) = 132300 oz or 8268 lbs or 4 tons less lifting for each leg if I ran with flats. Do you think I would be less fatigued?