Sunday's run

I ran kind of fast today for me. 5 miles 43:14, HR 163, about an 8:40 min/mile on the track at Bally's. Looking for speed on the run still. The HR seemed high for how I felt, I figured it was a high zone 3 run but the HR was in zone 4, I wasn't even breathing hard. The next run should be an easy pace run near 6 miles then a couple of faster sessions after that.