This is a big thanks to Dr Cucuzzella for posting what I find to be the most comprehensive 8.5 minute video on how to improve your running efficiency. His recommendation to lean slightly forward from the ankle has changed me as a runner forever. Before it would take me about 32-34 minutes to run 4.1 miles (3/10s of a mile shy of 2 full laps around the lake in my town, each lap is 2.2 miles -- you get the point, anyway), but I just easily did that distance in 27:39! I kind of pushed it the first lap (2.2 miles) and did that in 14:30, a 6:30 mile! Then I slowed my pace to what felt like a snail pace and finished the last 1.9 miles in 13:09, a 6:50ish pace! I figured I had slowed to an 8-9 minute mile that last 1.9 miles. Who'd ah thunk! Thanks so much again, Dr Cucuzzella.