Meredith Dietz Meredith Dietz Senior Staff Writer Experience Meredith is a marathon runner and stand-up comedian. As Lifehacker’s Senior Staff Writer, she covers personal fitness tech, home gym equipment, and more. Read Full Bio May 19, 2026 Add as a preferred source on Google Add as a preferred source on Google We may earn a commission from links on this page. Credit: Meredith Dietz Table of Contents As the average running watch gets increasingly high-tech, there’s a new normal for pre-race rituals: Staring at your watch the week before a big event, hoping the algorithm has good news for you. Both Garmin and Strava offer race time predictions, but how accurate are they, really? I put each platform to the test during the Brooklyn Half Marathon on May 16, 2026. Here’s what I experienced, and what I think every runner needs to know about what these tools actually measure.…