Scientific experiment

I’ve been on a journey for the last 10 years.  It all started with a charity white collar boxing match and the rest is history.  But as I’ve taken on new challenges, each with it’s own unique difficulty, my body has adapted and got stronger.  I’m treating it almost like a scientific experiment.  During the journey I have monitored my heart rate during every training session except when swimming and core workouts.  It’s a good indicator, amongst others, as to how I’m feeling at any particular time and many of my sessions have a target heart rate range.  But when I’m pushing it hard it just a case of let’s see where it goes.
I mention this because as I’ve been getting faster recently, I’m able to hold a higher heart rate for longer and maintain the fast pace.  While that might be an obvious sign of improving fitness it’s fascinating to watch and also requires me to mentally adjust.  2 years ago while running with my coach my heart rate was all over the place - no consistency.  We noticed that when it reached 163 my performance fell and I either had to slow down or even walk to get it back under control.  Yesterday my heart rate was 165 for 10 mins, 163 for 20 mins and 160 for 60mins and during those periods my performance didn’t fall - but I was working bloody hard.  Today on the mountains I topped out at 179 bpm for 5 seconds.  Sure I was tired but I kept going and finished strong.
This “experiment” will continue and my coach keeps a very close eye on every training sessions results so I’m not taking unnecessary risks.  At the same time I am enjoying my training and what lies ahead. I don’t want to limit my potential but at the same time realise I am doing this for fun.  But I also believe “we are all capable of so much more” so hopefully my story may persuade you to push the boundaries.  Have fun.