It’s easy to get caught up in all the details of strength training : how exactly to fit it into your run schedule, the ideal number of reps and sets to do to see results, and the perfect moves to support your miles. And sure, those particulars do matter when it comes to optimization, but the baseline for experiencing the benefits of weightlifting —including improving running economy , power, and longevity—is much more straightforward. As a certified personal trainer who’s worked in fitness for more than 15 years, I would say most runners overcomplicate strength training and how to fit it into a training plan. And a new paper from the American College of Sports Medicine (ACSM), the largest exercise science organization in the world, explains why simpler is better. Crafted based on 137 systematic reviews involving more than 30,000 participants, the ACSM Position Stand lays out the basic guidelines for gaining strength, power, and performance improvements.…