Distance running performances are insane! What’s the biggest change in training recently? Blended workouts instead of straight repeats. You used to see more 8x1k or 5x 1 mile. Focused on one stimulus or zone at a time. No or limited mixing. Now you see more blended: Where we are mixing the stimulus/zone. Consider Yared Nuguse's workout before his world record mile: 2k threshold- 6:00 2k- hard: 4:59 5x1k at 3:00-3:05 (threshold) 4x 200s in 26-27 He's bouncing back and forth between threshold work and very specific/speed endurance. You see way more of these types of workouts now than during the 2000-2010s. Back then, largely influenced by the Daniels/Vigil model, workouts were aimed at one purpose. Want to improve threshold? Go do 5 mile tempo. Vo2max? 6x800 at 3k pace. But in the 2010s, something changed. Renato Canova became popular and introduced more blended , alternations, and mixed workouts. You 'played' up and down the intensity ladder. Workouts like: -5 sets of (1200 @ 5k, 500 @ mile pace) -4x1k threshold, 8x400 @ mile, 4x1k @ threshold And so on become more accepted. We realized that we don't need to target one specific energy system, zone, or whatever. And that 'mixing' signals doesn't take away from the workout. This isn't new. Igloi was doing this in the 1940s. Even Bowerman and crew did a lot of mixed/blended work back in the day. But with the rise of physiological markers and zones we became convinced that we need to target one specific zone at a time. Modern training has recognized that's not true. Now, we still do straight repeats and workouts where we target one system. Those aren't going away! But what we realized is that we don't have to be stuck doing that. We can be more creative. We can target (and thus maintain) different adaptations in the same workout.