Heartrate lower than ever?

Physiology
1

Hi, I am seeing that my heartrate (per effort) is lower than ever.
History- 58 year old male, former cat 1 amateur, have ridden and trained steady for a good 30 years. Still train with intensity and do a couple gravel events per year.

I have notice a very low heartrate. A couple days ago I did 4x7 fairly hard (103% above FTP). Ave HR 130-133. max HR 140-143. Yesterday I did 3x15 min ~88% FTP. HR never got over 125.
I would say these values are 5-8 beats less than I would expect. This has been a trend, not a one-off.

Should I just adjust my HR expectations by that 5-8 beats? Or should I perform a ramp test to try to pinpoint HR?

2

Sometimes a lower than expected HR is indicative of fatigue, not improved fitness.

1 Like
3

has your resting heart rate changed? How did your muscular system respond to the workouts?

4

Heartrate is normal. Legs feel about average.

5

Assuming no dehydration, no heat stress, good nutrition/sleep, ect, the fact that your legs dont feel fresher at the same intensity with the lower heart rates noted raises a yellow flag. Your age is a consideration, not very old but no longer 36.

Maybe/likely no big deal. The cautious clinician would suggest, just to be on the safe side, an echocardiogram, and blood work including Troponin T, BNP, D-Dimer, and the other usual suspects.

One other thing: nutritional clinicians back in the ol’ days would look at mineral deficiencies as well with lowered HR

6
  • echocardigram over an EKG because your issue, if you have one, may be more subtle. The echo will tell you a lot. Your cardiologist would obviously have more insight.
7

boots2000,
If your MaxHR is accurate at 143, the intervals at 103% FTP are within the range I believe. Meaning those supra thresholds can illicit VO2 stress on HR and 90% of max would be 128 so this makes 130-133 abobe 90% which is anaerobic and inline with effort. I also would say that the 125bpm at 88% FTO is inline with mx hr calculations. Are you establishing this based on threshold HR or Max HR? If it has been a while since you raced or did a max HR assessment I would do a 1min all out like your life depended on it effort, into a hill is best or do a standard 3-5M effort on the flats all out and see what your 1 sec max HR is.

8

Fpike, what you are saying makes sense. I really don’t know. His concern was that his hr numbers had dropped, but his legs do not feel any stronger, so the change does not appear to be due to increased fitness, although how he feels is subjective.

Approaching 60, consideration of heart issues, everything else being equal, approaches the horizon.