Just ran my first two weeks ago. Training at pace in weeks prior was just under 80% of max at goal pace at up to 22 miles. Warmed up race day ( all training in single digits to low 30’s F). Local course so all my runs were on the course. Warmed up to low 60’s and sunny on race day, ran at 85% heart rate average with a couple peaks in last few miles on hills within 5 beats of max.
Didn’t bonk or hit a wall but definitely didn’t have much left at end. 46 year old, resting hr 48, max hr 190 ( from races). Negative split by about 30 seconds. My goal was to run first one at 80 pct ish. Weather didn’t help and worked whole time, never felt comfortable. Peaked at 75 miles a week and held 70+ for four weeks at end before a two week taper.
I know this is hobbyjogger but my experience. Going to keep up training and do better in fall on next attempt. My time was 3:13:30. Was happy with it, not good by standards here but felt I performed close to potential given circumstances