Garmin vs Strava: My Marathon Prediction Was Off By ONE Second

I’ve been chasing a sub-three-hour marathon for years. After failures in Berlin due to heat and training errors, I finally took my shot at redemption in Dresden. But this video isn't just about the run; it's about the data behind it. I tracked my training using both Garmin and Strava to see which algorithm could actually predict my race day performance. The approach is totally different: Garmin looks at your "Engine" (Biology, VO2 Max, Heart Rate). Strava looks at the "Crowd" (Big Data, Training Logs). Going into the race, their predictions disagreed. One was conservative. The other was optimistic. But when I crossed the finish line, one of them was accurate to within literally one second. In this video, I break down why they disagreed, how the technology works, and which one you should actually trust for your next race. Drop a comment: Are you a "Garmin Optimist" or a "Strava Realist"? Follow me on socials: 🏃🏻 Strava:   / strava   📸 Instagram:   / racetosubthree   📹 Tiktok:   / racetosubthree   #MarathonTraining #Sub3Marathon #GarminVsStrava #RunningTech #RacePredictor #Garmin #Strava #runningdata 0:00 Intro 0:39 How do they both work? 2:29 What information do they both have? 3:36 The Predictions 4:35 What does this mean for you?