Breathing Rate in Computer Calculations?

[boulderjohn]

Just to point out a problem with using heart rate, my resting heart rate is in the low 40s. I do a lot of exercise on a stationary bicycle with built-in heart rate monitors. When I am chuggling along, it will get all the way into the low 70s. That is where most people start, before they begin to exercise. I have to work pretty hard to get my pulse rate up to 100. Other people get it there with little effort at all.

 

[ATJ]

Just to point out a problem with using heart rate, my resting heart rate is in the low 40s. I do a lot of exercise on a stationary bicycle with built-in heart rate monitors. When I am chuggling along, it will get all the way into the low 70s. That is where most people start, before they begin to exercise. I have to work pretty hard to get my pulse rate up to 100. Other people get it there with little effort at all.

To add to this...

I am fairly fit (according to my Garmin Descent Mk1 my VO2 Max is 47 giving me a fitness age of 20 when I'm actually 60). My resting heart rate is low 50s but if I go for a run I can easily get my heart rate over 170 and my average for the run is often around 160. The few times I measured my heart rate while I was diving it barely got over 80 and that was only a couple of times. Most of the time I was barely over resting rate.

How would a dive computer account for John's and my heart rates?

 

[scubadada]

The Scubapro Buhlmann ZH-L 8 or 16 ADT MB algorithm has been discussed many times before. For HR or skin temperature to apply, you must wear the chest strap and and enable the function. For breathing rate, it can be set from -12 to +12, the negative number having the least effect. Scubapro "Human Factor" diving is a secret. However, clearly, all these factors make the baseline algorithm more conservative. My impression, from ScubaLab hyperbaric unit testing, is that the Scubapro deco algorithm is moderate to conservative at baseline.

 

[Centrals]

Light Exercise During Deco Stops | Office of Marine and Aviation Operations

Came across a paper many yrs ago but could not locate it with similar finding.

 

[Blackcrusader]

Just to point out a problem with using heart rate, my resting heart rate is in the low 40s. I do a lot of exercise on a stationary bicycle with built-in heart rate monitors. When I am chuggling along, it will get all the way into the low 70s. That is where most people start, before they begin to exercise. I have to work pretty hard to get my pulse rate up to 100. Other people get it there with little effort at all.

Wow that's pretty much Zombie land for your heart rate. I have a slow heart rate... this is from me cantering up 8 flights of stairs to see a heart lung specialist this year. He had me do that as he wanted to see it at a non resting rate. So when I am diving my heart rate is low 50's as I dive like a corpse, in other words I don't move a lot if I can avoid it.

In my office I workout several times a day on a rowing machine Viking 2 Plus. Lets me give myself a workout 10 minutes every hour or so. As I hit 60 years old I wanted to make sure I'm still good for diving lol.

 

[Blackcrusader]

OK I do not know if this helps. I do not use AI on my Perdix. However I do use a Cressi Digital Console. From any point of the dive it let's me know time to 50 bar. So if say diving into a strong current at 30m depth I would know time left to 50 bar at current consumption. I've found it to be quite accurate. I've been on a days diving where the dive shop planned the last dive of the day into a current so it's my third dive and they give me a workout but it's also generally 20m MOD.

Another thing over the last 200 dives I've done my average depth is around 15.5m. I do deep dives to 45m but I'm basically recreational diving. Where it says RANGE is the time to 50 bar at any point of the dive.

 

[Centrals]

In my office I workout several times a day on a rowing machine Viking 2 Plus. Lets me give myself a workout 10 minutes every hour or so. As I hit 60 years old I wanted to make sure I'm still good for diving lol.

View attachment 627783

Good on you.
118 over 75
I have no problem either at slightly advanced age!

 

[GJC]

Clearly as you go deeper, your gas consumption rate increases with gas pressure, which accelerates the accumulation of N2 in your body. I get that basic physics and physiology. Does anyone know if computer algorithms account for actual breathing rate? And true air consumption rate?

As an example, let's say you're diving at 10m and then you go to 30m and you're breathing rate and effort are identical at each depth. One can expect the air consumption rate to be double at 30m that it is at 10m.

But what if you're working at 30m or excited, and your breathing rate is 50% faster at 30m? That would put your actual air consumption at around triple what it would be at 10m. And accumulation of N2 would be proportionally higher as well.

So do computers, and I guess more accurately air integrated computers, use the actual air consumption rate in it's NDL calculations, or does it just keep track of how long the diver is at any depth?

Thanks in advance,
Rob

Your air integrated computer only knows how fast the pressure in your tank is dropping over time. You can get it to calculate your SAC if you tell it (or the app on your home computer or phone) what the capacity of the tank is that you used.

Breathing rate by itself is not helpful in determining SAC or RMV without knowing how much air is moved with each breath.

 

[Blackcrusader]

Good on you. 118 over 75 I have no problem either at slightly advanced age!

One day perhaps we can do some recreational dives together as we are close wise on flight times to good dive spots in Asia.

 

[Hatul]

To add to this...

I am fairly fit (according to my Garmin Descent Mk1 my VO2 Max is 47 giving me a fitness age of 20 when I'm actually 60). My resting heart rate is low 50s but if I go for a run I can easily get my heart rate over 170 and my average for the run is often around 160. The few times I measured my heart rate while I was diving it barely got over 80 and that was only a couple of times. Most of the time I was barely over resting rate.

How would a dive computer account for John's and my heart rates?

In the Galileos and the G2 you tell it your base HR so it compares the current HR to a base value.