HR Question

[dblinden]

There was a time when I cycled a lot. Once I was well trained, I could tell my heart rate within a couple beats without having to rely on using a monitor. I could also ride at a beat or two under AT for almost an indefinite time period (hours) without any increase in HR as long as I maintained constant effort. After the bike came running and I noticed that at times my HR would gradually increase over a session even though the effort (read pace) was constant.

Since starting up with the erg recently, I have seen this same tendency, but even more pronounced. This makes it difficult to train at a set HR band since I will move into a red zone and can't maintain pace. (obviously, I could slow the pace to stay in that "band") It also makes it difficult to maintain a set pace for a longer piece, say one hour. For example, constant HR for 30 minutes, but as I approach 45 minutes, my HR will steadily ramp up and I have to let something go in order to finish the hour.

I would like to know what causes this to occur. My only thought is that it is just due to lack of fitness. Wondering if there are other factors?

Thanks - Dennis L

[jackarabit]

Excellent explanation of cardiac drift here: http://www.twentysixtwo.org/images/Slow ... Part_2.pdf

Jack

[hjs]

There was a time when I cycled a lot. Once I was well trained, I could tell my heart rate within a couple beats without having to rely on using a monitor. I could also ride at a beat or two under AT for almost an indefinite time period (hours) without any increase in HR as long as I maintained constant effort. After the bike came running and I noticed that at times my HR would gradually increase over a session even though the effort (read pace) was constant.

Since starting up with the erg recently, I have seen this same tendency, but even more pronounced. This makes it difficult to train at a set HR band since I will move into a red zone and can't maintain pace. (obviously, I could slow the pace to stay in that "band") It also makes it difficult to maintain a set pace for a longer piece, say one hour. For example, constant HR for 30 minutes, but as I approach 45 minutes, my HR will steadily ramp up and I have to let something go in order to finish the hour.

I would like to know what causes this to occur. My only thought is that it is just due to lack of fitness. Wondering if there are other factors?

Thanks - Dennis L

Slowly heating up and loosing fluids make the hf drift up at constant pace.
So yes slow down, and don,t start to fast. If you reach you max zone early, you can,t keep pace. So start out slower, this way your hf has room to drift.

[jamesg]

I would like to know what causes this to occur. My only thought is that it is just due to lack of fitness. Wondering if there are other factors?

I think rowing uses most muscle, cycling least, and this could have it's effect somehow, maybe by having to get rid of waste products of differing chemistry and having to deliver more oxygen. There must be something that drives up HR; so what can it be if not accumulated rubbish sending us an alarm signal?

Cyclists and runners are usually careful to replace sweat by drinking, not so easy while rowing with our arms and hands. It's often said here that a ½ Marathon (around 90 minutes) doesn't need water; runners and cyclists probably drink a lot more often.

So if you do basic CV rowing training (90 minutes UT2), but stop to drink every 20-30 minutes or so, you shouldn't see much drift. If you do, probably you were going too fast, which is typical of amateur ergers - go fast and hope for the best. Certainly trying to go too fast doesn't make my HR drop.

[steveroedde]

I am not certain, but I believe there may be several issues at play. One is hydration (as pointed out by others), another is core temperature which has an impact on hydration, but also has an independent impact on cardiac drift. I too cycle. When on the bike, the cooling effect of the wind mitigates the second variable (as well as the first). I am certain you can recall the difference trying to maintain steady effort on a 9% grade going 10-3kph for an hour in the heat as opposed to doing the same at 35kph. You will get more drift on the hill climb because your core temp will be higher (independent of how much you drink). Ditto running! Erging, in a gym, especially with no fan and temps too warm...is brutal!

My erg is in an unheated garage, presently around zero C and I also have an industrial fan going. No shirt. Only a couple of beats of drift at Z1-2 over 2h with no fluids. My skin temp is very cool! I believe glucose infusions also mitigate drift but can't recall the study. Then again, I happily cycle for 3h without bringing water-bottles.

Beyond the inability to maintain pace, I am not sure i would be concerned with drift. If you can't maintain pace, slow a bit. If you are trying to get fit/fast on the erg I think the same principles of polarized training apply to rowing and cycling and Z1-2 should be the bulk (possibly as most believe, at low rate) and intervals above LT...with next to nothing in the dead zones between. In Z1-2 I doubt the drift would be limiting.

[dblinden]

Well, I am definitely an amateur with the erg. I am also a novice when it comes to using HR as a structured part of training. On the bike, I had enough experience to know the line between high aerobic intensity and going into red zone and could stay just under for long periods. Living in the south, I was pretty well heat trained, but I always consumed a fair amount of fluids (typically one large and two small bottles worth over a 3-4 hour ride). Most of these rides were with a group of other very fit cyclists so it was essentially doing variable intervals except when I rode alone or just with one friend.

On the erg, I also set up a fan, but the ambient temp is probably 68 degrees. Within four minutes, I am already warm and by ten minutes I am thinking I want a drink. I have been waiting until 30 minutes to drink and then at 45 I really want something again. You can drink at 25-30 mph on the bike and not miss a beat, but your pace dives if you stop on the erg. I can't pull one-handed.

So anyway, I see upward drift after 30 minutes and it continues to increase until I either get too uncomfortable to maintain pace or I am just pulling while in a higher HR band. But I definitely cannot go at a set pace (perceived intensity) indefinitely like on the bike.It's not a big concern one way or the other, but it makes it difficult for me to select a pace to complete a piece within a targeted HR range.

Thanks - Dennis L

[Cyclingman1]

Beyond ability and fitness, the biggest factor in endurance athletic performance is the ability and/or possibility of dissipating heat. That depends on a persons surface area, outside temperature, humidity, wind, hydration - I'm sure there are other factors. In as much as those factors are in the wrong direction and or changing in the wrong direction, a person's core temp will rise and impact internal blood flows, heart rate, and performance. I agree that the lack of wind for most indoor rowers has to hurt. As a long time runner and cyclist, I notice that one can get really hot on a rower very quickly. I look forward to winter for indoor rowing because my basement cools considerably. I always row shirtless with an industrial fan and even that helps only partially when it is warm. A rule of thumb among runners is that temperatures above 50F will affect performance, more so as the temp rises. And that is probably high for rowers.

[Carl Watts]

Ambient temperature and fluids have the biggest effect on the HR drift for me.

Same pace and duration can see my HR at 10bpm higher at the finish and a much steeper curve. A good practice is to measure your resting HR before you row, it gives you a good insight into what to expect. Also as the week progresses you tend to get more tired and after 5 days straight your resting HR can be elevated.

The Erg suffers from exercise without airflow so setup a fan and also don't try and row in a small room with the windows closed ! oxygen deprevation sets in none of these problems exist in road cycling.

Fitness and intensity change the slope angle significantly. Using RowPro you can see your HR as a graph from the start to the finish of the row. Good fitness and low intensity it is possible to see the HR a near flat line. A Cooldown row will actually see a negative slope if the pace is slow enough.