This is in no way a completely fair comparison as many variables were not equal. I’ll list the factors that I think affected the times between the two runs and let you come to your own conclusions.
10k with Vibrams (46:50, 7:27 pace)
Sleep: 7 hours
Eating Day Before: Faily Healthy, Stuck with Paleo
Breakfast: Bacon and Eggs, with FSR Energy Drink
Wake Time: 8 am
Warmup: 1 lap
Weather: Sunny slightly cold
Fellow Runners: Around my level (Came in 2nd for Males)
Workouts: No workouts 2 days leading up to run
Motivation: Planned to run
10k with Sneakers (48:25, 7:51 pace)
Sleep: 6 hours
Eating Day Before: Somewhat Healthy, but had beers in the evening
Breakfast: None
Wake Time: 9 am
Warmup: None
Weather: Sunny slightly cold
Fellow Runners: Fast (Top finishers beat me by 1 mile, came in last for Males)
Workouts: Weights 2 days before, incline sprints day before
Motivation: Undecided about running
As you can see I was way more prepared mentally and physically for the first run. I’m not sure how much of that accounts for the 1:35 difference between the runs. A few seconds of that time was lost by me forgetting to use my inhaler. I had to take a small detour and stop in the middle of the first mile to grab and use it from my backpack.
I’ll briefly describe the after run comparisons. I can easily say I was tired after both runs. With the Vibrams I felt soreness in the lower calfs while with the sneakers it was more draining on the legs overall. I wore toe socks for both runs and I believe I might have a blister from running in the sneakers and no ill effects in the Vibrams. I’m assuming this is caused by the slippage between the sock and the shoe so I believe energy transfer on the Vibrams might be more efficient.
From my subjective view, I felt better during the Vibram run, but given the prep and time differences it’s hard for me to say that I was faster with one vs the other. The only conclusive thing I can say is that running in the Vibrams has not made me any slower than before. I’ll also toss in that while I was disappointed with a slower time on the 2nd 10k, I don’t believe I’ve been able to keep this pace in a while. I believe that the workout regimen I’m currently on is showing dividends. I will continue to stick with it and will plan to have a better comparison in the future.