Effect of heat on pace: down to which distance ?

[HornetMaX]

Hi all,

I was 2 weeks on vacation (at 1900m altitude) and I did some light training (alternating 1 day light weights, 1 day 1h rowing at a calm 2:12 pace, on a model C with a PM3, in suspect maintenance status). My HR in the steady state session was in the ballpark of what I did at home just before the vacation.

Back at home I did an HM today and went for my usual 2:12 pace but my HR was much higher than usual: today 2:14 pace for 155 avg HR, 3 weeks ago 2:12 pace for 146 avg HR. That's a lot of difference.

Then I realized that today I had 31C (and 76% humidity) while in the previous HM I had "only" 26C (didn't check humidity but was for sure lower).
So yeah, probably not the right time of the year for a long TT

Question: down to what distance is the impact of heat on your PB not so important ?

[Dangerscouse]

Ime heat and humidity are an issue for more or less every distance, but it's probably a tipping point from 2k upwards.

[Carl Watts]

Heat and humidity make a big difference.

I'm surprised really that the PM5 monitor never incorporated sensors for both so they could get automatically recorded with your results and possibly then allowed you to do some correction.

I have a HTC-1 very cheap clock and temp with humidly sitting beside the rower, this could have been built into the PM5 for like $3.

[HornetMaX]

I'm surprised really that the PM5 monitor never incorporated sensors for both so they could get automatically recorded with your results and possibly then allowed you to do some correction.

I have a HTC-1 very cheap clock and temp with humidly sitting beside the rower, this could have been built into the PM5 for like $3.

That's a very good idea indeed: feature request for a PM6 ?

I have one cheap temp/hum sensor too, I'll start writing down the temps/humidity manually (at least for long sessions).

[Carl Watts]

Yes I'm still manually recording mine in the notes for the logbook.

Same with Zwift, it has a notes area. I record the temp and humidity as well as how long my Heartrate takes to drop to 116, which is another function the PM5 should have had, they could have even graphed it as a heart rate decay and ran a timer so I don't need to hit a stopwatch and watch it.

[jcross485]

I agree with the sentiment that a simple temperature and humidity gauge on the monitor would be a nice addition and something that would be worth the extra $$ for those of us not rowing in a pretty controlled gym or home. Personally, my garage fluctuates heavily throughout the year and even the time of day based on the way the sun is hitting the garage door.

As far as how much of an impact it has, I would say for sprinting (500m or under), next to nothing unless you are doing interval repeats. As the distance goes up, it has an increasing effect - the longer the session, the more of an impact.

[jcross485]

To add on, there are a lot of online running calculators where you can plug in some data (temp, humidity, dew point) and it will spit out adjusted paces.

They are specific to running but I don't see why they wouldn't work for rowing if you put in the data and distances adjusted to miles or km as well as paces adjusted to min per mi or min per km.

With running, you will get a slight cooling effect by moving through space as opposed to being in a relatively fixed space but using a fan would likely offset that slight cooling effect.

[Carl Watts]

A fan makes a big difference on the rower but the PM5 is also in the airstream so if the temp dropped a degree or two the monitor would record it.

Just to note that moving air has like a FIVE fold increase in cooling over static airflow, so even without a significant temp drop of the air the fan makes a huge difference.

[JaapvanE]

Yes I'm still manually recording mine in the notes for the logbook.

Started to the same as well. It is a shame that that kind of data can't be recorded in its own dedicated field so it could be analysed later. Even dedicated training tools like intervals.icu and RowsAndAll.com don't record this data.

Same with Zwift, it has a notes area. I record the temp and humidity as well as how long my Heartrate takes to drop to 116, which is another function the PM5 should have had, they could have even graphed it as a heart rate decay and ran a timer so I don't need to hit a stopwatch and watch it.

Interesting. Why the drop to a specific HR and why 116?

There is quite a lot of evidence that links health to Recovery Heart Rate, where the Recovery Heart Rate is the difference between the last recorded HR during intense excercise and the HR after 1, 2 or 3 minutes. To me, it was the reason to add this as a function of OpenRowingMonitor. Intervals.icu can actually record it HRR1 (HR after 1 minute recovery), although it does not seem to be used in any way.

[Carl Watts]

Heartrate recovery is a really interesting stat.

I choose 116 as I still have a high max its in the 180's. Typically people choose like 100 as a nice round number. Typically depending on the intensity and duration mine takes from 1:30 to 2:30 to recover.

100 is not great for me my HR starts to plateau pretty badly below 115 and revery time drifts into 3 or 4 minutes.

The faster the recovery the better the fitness.

[JaapvanE]

100 is not great for me my HR starts to plateau pretty badly below 115 and revery time drifts into 3 or 4 minutes.

The faster the recovery the better the fitness.

Yeah,

I seem to be stuck around 108, so your approach makes a lot more sense than that nice round number.

[aegis]

Heart rate recovery is an interesting metric, I know that my average heart rate for the same intervals have gone lower even though the splits have gotten faster. It's probably a simpler statistic to track compared to time to recovery and the two are highly correlated.

For a more unbiased analysis, you probably need to do the same splits so that only one variable is changing at a time. I am pretty sure if you have been training consistently, the later one will be at a lower HR provided there are no big external factors.

[jcross485]

A fan makes a big difference on the rower but the PM5 is also in the airstream so if the temp dropped a degree or two the monitor would record it.

Just to note that moving air has like a FIVE fold increase in cooling over static airflow, so even without a significant temp drop of the air the fan makes a huge difference.

The more you know! I appreciate the insight, it really helps a ton.

[Carl Watts]

A fan makes a big difference on the rower but the PM5 is also in the airstream so if the temp dropped a degree or two the monitor would record it.

Just to note that moving air has like a FIVE fold increase in cooling over static airflow, so even without a significant temp drop of the air the fan makes a huge difference.

The more you know! I appreciate the insight, it really helps a ton.

Yeah I waited 10 years too late to get a decent fan and thrashed away in a small room in literally a pool of sweat. Takes about 30 minutes now with the fan on before I even need to reach for a towel.

[aegis]

I sweat a ton and a headband definitely helps!