Training “zones” different after rest/blood who knows!

Ok, random question but it’s got me a little stumped/questioning the answer. I guess the long and short of it is that I’ve lost threshold power

I have a local hill, 25mins up (8% average). Two runs:-

Run 1- 304w average 152bpm average 24min44sec. Not peak fitness last year, but pretty good. 152bpm for me is 10b under threshold, so basically sweetspot

Run 2- 303w average 170bpm average, 24mins 43sec. Good fitness (better than last year) but I’ve had 4days bed rest and about 200ml blood for tests. 170bpm is normally my target to collect minute for Vo2 work. In a zwift race if I get to 175 I’ve only got seconds left. My ramp tests usually end 180bpm (my absolute max)

For reference, my threshold heartrate is low 160’s. Was the 2nd run (yesterday) effectively working the vo2 zone? I felt fine, it’s just my heartrate for the last couple of days has been 15bpm above where it “normally” would be for training zones!

Bit of an odd one, I didn’t know if the muddling the numbers changed the outcome!

If you were on bedrest, it sounds like you were sick. If this is the case and you also gave blood, then it is pretty normal to lose power and have a higher heart rate. You may need to take it easy for a couple of days to recover. start out slow and stay away from intervals.

This does seem odd. He didn’t lose power though. Held the same for 20+ minutes at what should be - given his history - VO2 max hr level.

How did you feel after this effort? Should, by the numbers, be a higher RPE than previous.

Personally, if I did a 20+ minute effort at well over LTHR and into VO2 max, I’d be questioning my hr monitor

Ahh sorry, I’ve not been ill- just part of a medical trial. It was a rest day before, then 3 “inpatient” days with bloods drawn etc.

I normally train 6-8hrs, upto 12 if I can get a long ride. I saw this as a partial forced recovery week! Well, and money

Hi. I didn’t log the rpe last time, this time was a solid 9/10, started off a bit strong then paid for it on the second half which made it feel a little harder.

I presume my HR monitor is fine, I only say that as the indoor session yesterday (haku) was also reading higher than normal on a different monitor. Subjectively, the power feels appropriate but the HR is elevated

Blood plasma volume decreases with longer rest plus you actually took some out! So your heart is making up for it by pumping faster.

Try again next week after a bit of training and fully hydrated.


Good shout. I don’t feel so bad for the mid-long term now!

On the trainer now (low stress sprintervals) and it’s already more appropriate, defcon reduced already

Cheers all