Hi all,



Is it a normal symptom that after some time of training with low heart rates
(aerobic zone, below 70% of Max HR or even less) the body, so to speak,
switches to lower heart rates? I.e. it gets harder to ride on higher heart
rates.



For roughly a month I've been training below 70% of HRmax and recently I
observed, that my heart rate during relaxed pedaling is significantly lower
than it used to be a month ago. I wonder if it's just a normal, let's say,
adaptation, and my aerobic capacity has increased, or could it mean
something else (overstraining maybe?).



My rides before I noticed the above were 2,5 h long on the avg, around 13
hrs a week, below 70% hrmax, half of the time even below 65% hrmax. I'd like
to add that low HR is typical for me (45 resting, 24h avg 55), yet at
present it's like when I accelerate to above 70% of HRmax I start to fell my
legs getting heavy. I don't remember anything like that happening last
season. I hope that when I introduce some "faster", anaerobic rides, this
will change back to "normal".



Thanks in advance for any ideas,

Lechu