So, in light of that sentiment, I ran a little faster on the treadmill after work today. I set it at 6.4 miles per hour, as opposed to the 6.0-6.2 mph I was running earlier. It definitely felt faster, but I'm going to continue to challenge myself. I'm so used to running at 6 mph (10 minutes per mile)...it's too comfortable. I need to push myself.