r/runningquestions

I ran my first full marathon in March and finished in 5:31. I definitely went out too hard at the beginning, even though my Garmin had predicted a 4:20 finish.

I ran another marathon on May 2nd, but this time I paced completely by feel and heart rate, with only HR displayed on my watch. I finished in 5:03 and, surprisingly, I wasn’t completely destroyed afterward. That felt like a huge improvement in both pacing and endurance.

After that, I signed up for a 5K because I wanted to see what kind of speed I actually had. Garmin predicted a 23:30, but I ended up running 22:48.

Since then, all of my prediction times have continued trending downward. My current Garmin marathon prediction is now 3:59, so I’m starting to feel like sub-4 is becoming a realistic long-term goal. Right now, I’m mainly trying to figure out fueling and hydration.

I used Honey Stinger gels during my marathons, but they upset my stomach. I recently switched to , so I’m hoping that works better. Around mile 20 is when my legs really start to fall apart, and I suspect part of that is from underfueling. I also get really thirsty late in the race, but at the same time I stop wanting to drink anything, which is something else I need to work on during training.