Interval training is different, it's supposed to spike your heart rate for short(er) periods, so that makes sense. When people are talking about running easy or

Interval training is different, it's supposed to spike your heart rate for short(er) periods, so that makes sense. When people are talking about running easy or being able to have a conversation, they usually are talking about low to moderate intensity aerobic zone or "zone 2", which goes to 75-80% HRmax depending on who you're asking. Some would even explicitly recommend 120-130 bpm range.