Time to dial in that engine. 🏃‍♂️🔥 This 8-round interval session moves you through Zone 3 → Zone 4 → Zone 5 with just enough rest to keep the effort high. Use your heart rate zones to guide intensity and build aerobic power with precision. •Zone 3: 70–80% of max heart rate – moderate, aerobic effort •Zone 4: 80–90% of max heart rate – hard, threshold effort •Zone 5: 90–100% of max heart rate – very hard, anaerobic effort Pace smart, finish strong. Save it & tag a friend who loves a grind like this 👇 #ZoneTraining #RunStrong #KStoneConditioning