I just finished a 18.22km cycling that lasted about 0hh:45mm:46ss !
Third session of bicycle roller. We continue with the same cadence and the same pulsation target (60-65%) as in the other activities. In this session the difference is that we have increased the activity time by just over 5 minutes.
As you can see in the graph, the heart begins to respond quite well to this demand since the increase in pulsations is minimal or does not exist.