I just took two weeks off to nurse a lower back strain (still recovering) and decided to do a moderate one hour Z2 ride on trainer to make a very slow gradual progression back to riding. My HR on a Z2 ride is 125-135. My HR this morning was 160-170 which seems absurd. For reference that would be my HR on a high threshold 45 min climbing PR Ride.
History.
Ride 200-250 miles a week. RHR 36-39 MHR 192. 42 Male.
Last two weeks RHR has risen to 40-44.
Have done almost no activity in that time.
There’s probably other explanations but a lower RHR and AHR may suggest that you were fitter two weeks ago or conversely you were worn out two weeks ago and they were suppressed then. Another possibility is that you are coming down with something which your body is fighting causing both the RHR and AHR to be higher.
I’ve seen that type of fitness loss / zone creep after a month off. What I do, and supported by my coach, is when there is that big of a fitness loss, is to ride by HR until power comes back.
General rule of thumb from the past two years, where I’ve consistently been putting down about 8 hours/week on average, is that:
1 week off will require about 3 days (Mon/Tue/Wed) to bring things back to where I left off. But I’m talking about creeping from 135-140bpm up to 140-145bpm in this scenario.
4 weeks off will require about 4 weeks, and I ride endurance by HR for the first 2 weeks and start to sprinkle in short intervals on week 2, and go longer on intervals in week 3, and by week 4 I’m nearly back to where I left off. Completely back after 8 weeks.
So the rule of thumb I’d use for a 2+ week layoff is to multiple by 2. Two weeks off = 4 week block to return assuming consistently training for a long time before then (and having been doing classic training with a lot of endurance). And 4 weeks off = 8 week or 2 blocks to return again given the same assumptions.
Jeff from NorCal Cycling YouTube channel uses that same rule of thumb.
Same for me. I think at least part of it is reduction in blood plasma volume, which is one of the first training adaptations to both come and go. Also simply being fresh and carrying no training fatigue. FWIW I take a different approach to @WindWarrior and just ignore HR for the first week or 2 back and go by RPE instead. HR always comes back down to normal within those couple of weeks.
My HR zones for steady efforts haven’t change in 6 years, so they are pretty reliable for long-ish efforts at or below threshold. With an understanding that HR ramps up during the beginning of the interval.
@AussieRider if you measure your HR 1 minute after you stop riding how much does it drop?
I agree 45 BPM is huge. I was thinking HR monitor error like when you ride under high tension power lines. I’m sure you crossed checked values with a stop watch but, if not I’d verify monitor accuracy.
I did another Z2 ride yesterday and my HR average was down 11 bpm. Still about 10-15 higher than average but it’s coming down. What’s also odd is my resting Hr keeps going up. Two weeks ago it was 35-39. This morning it was 45. I haven’t seen it that high since pre cycling days.
Another thing is my Garmin body battery (hrv) hasn’t recovered once in two weeks. Since I got the watch a year ago. 99% of days it would hit 97-100% by the morning. In the last two weeks I don’t think I’ve seen it above 80%. Even though I’m not riding and getting plenty of sleep.
Changes have been. Lower back strain. No riding for two weeks. Covid and flu shot 13 days ago.
Ah I missed that. Healing bodies take a lot of energy. Give it a month and prob back to normal.
Reminds me of a crsh years ago…8 ribs, clavicle and punctured lung. The lung stans are getting so good they can pick up all kinds of “abnormalities” that can get you worried about cancer etc…point is tech is good but, it can lead us down a wrong path.