Hi,
I have noticed during long trail running races in the mountains that after 8-10 hours of running/power-hiking that my breathing rate goes up significantly while everything else seems to slow down. I would like to understand what is going on so that I can adjust my training to go past what feels like a performance bottleneck.
So this is how a race (>100km with a lot of height gain) typically looks like for me:
1. 8-10 hours where HR slowly but surely goes down (from high Z2 to a low Z1), high-to-moderate power output, “normal” breathing rate (i.e. breathing is proportional to HR)
2. 10 hours (or more…) with relatively steady HR (low Z1), moderate-to-low power output, high breathing rate (feels similar to a Z3 workout, but HR is definitely in Z1 or below and pace is rather slow).
I have some issues with alimentation, typically finding it harder and harder to regularly ingest carbs during long races (a rather common issue I suppose) and I was wondering if that could be linked to this high breathing rate or there is another cause. Some kind of respiratory fatigue or inefficiency kicking in, perhaps?
So my questions are:
– is it typical to experience high breathing rate together with low heart rate in the second half of a 20h run?
– can that be improved with some sort of training?
