I think so. Here are some stats from my last ride. It's what I consider a Base ride, Base being the basic core road ride I do (I do Intervals, Base and AR). On this ride I spent 57% of my time at Level 4 and above.

Level HR Time Percent

1 AR RHR-129 0:12:05 12%

2 Endur 130-140 0:14:10 14%

3 Tempo 141-148 0:15:56 16%

4 SS 149-160 0:41:15 42%

5 Thresh 161-165 0:09:07 9%

6 ST 166-MHR 0:05:15 5%


Total Time: 1:37:48

LI Time: 0:42:11

HI Time: 0:55:37

HIR: 57%

Avg HR: 145