Originally Posted by
JPradun
It takes an extraordinary amount of concentration to hold 85%HR for 1.5hrs.
Since there is great variation in people's lactate threshold heart rate relative to max heart rate (depending for example on stroke volume and fitness), there is no way to generalize whether a certain percentage of max is easy or hard to maintain. My LTHR is about 90% of max, and I can easily maintain 85% for more than a couple of hours. There is absolutely no significance to that.