Óverweight guys,Diving and Nitrogen

[juggernutt]

Not sure where to place this.

But a LDS guy told me that there's recent study that if you're an overweight guy, you run the risk of not being allowed to dive anymore.Some organisations have banned guys who are above a certain weight/height/fat combo.

High fat percentage retains more nitrogen than normal divers.
I was adviced by the guy to always add 1 step on the Padi diveplanner for safetysake if I dive at a certain depth for a longtime. So if I dive a long time at 14 m...and that's the max depth. I should use one step further. So 16 meter when I plan the next dive.

But if I reach 14 m for just a short time ,but dive mostly at 10 m. I could safely follow the diveplanner.

Anyway seems reasonable. Anyone know about this new reaserch and it's findings?

 

[The Iceni]

To my mind there are two factors to look at with regard to obesity and diving.

1. The first is the general level of cardivascular fitness
2. It would also appear that many believe excess adipose tissue increases the risks of DCI. Is this true?
   [/list=1]

1. 
   
   Not too long ago there was some debate on Scubaboard about the usefulness of the body mass index (BMI) as an indicator of general cardivascular fitness. While it is true that the obese have an increased risk of cardivascular events this risk is multifactorial and the BMI is far less important than general "fitness" and smoking, for example.
   
   The UK's Health and Safety Executive requires the assessing doctor to grade cardiovascular fitness in professional divers by means of some form of exercise test - such as a simple step-up exercise with the heart's response to exercise and the speed of recovery being assessed.
   
   I am not sure that the risk of DCI is directly related to the amount of adipose tissue . True it will dissolve more inert gas but it is a slow tissue with a very poor blood supply and more importantly the body fat (unlike the "fat" in the CNS) is not vulnerable to pathological injury caused by DCI.
   
   My assessment is that the infarction of body fat will hardly be life threatening! I may be wrong but I assume any added quantiities of nitrogen offgassing from such excess adipose tissue will not be the limiting factor. Generalised cardiovascular fitness and efficient tissue perfusion will be.
   
   Not knowing your vital statistics, I would suggest that as long as you are not "obese" juggernutt, standard deco schedules will provide a good safety margin.

 

[juggernutt]

What's obese?
I am fat that's for sure.
I can play basketball and such. No limits in sports.
Even though I get injured in sports quicker than usual.

You think being just a recreational diver, it's ok to be fat? With OK I mean no outright dangers?

I have never seen a fat instructor,DM etc yet...
But I am not looking to be a pro in scuba...just fundiving.


But thanks for your quick reply Doc'

 

[GreatInca]

I am very overweight. 5'6", 265. I have large leg muscles and a huge lung capacity, however My weight is often under-guessed by about 10-15% (My age 20-25%). But I can't run a mile without stopping though, but can ride an excercise bike at level 20 at 55-60prm and Level 30 (most only go to level 20) at 40-45 rpm and sustain it because of my lung capicty. HR runs about 170-175, at the level though, which is too high to sustain beyound carb to fat burning switchover wich i read is gradual betwen 20-40 min; 20-30 for me. Have to keep HR at 155-160 to easily go beyond 20-30 min, which is level 13-15 @ 55-60rpm on a bike. Bike is my best aerobic exercise (elipitical 2nd) because my excerise outside the gym (which I go very intermittantly despite a 3yr pre-paid membership at a incredible rate for a big-brand gym - 24hr fitness -- $678 for 3yrs w/ 5 PTs, nationwide, no restrictions, and $50/yr after that) is almost entirly riding my bike to/from work with occasional soccer and swimming/scuba. Treadmill is my worst aerobic excercise.

But anyway, I dive without problems despite being 100lbs over the recommended weight for 5'6" (Heavy frame too). Main disadvantage is the weight that you have to carry. 18lbs at weight test (with a shorty -- probably 15 for fat -- 45 lbs with a 7mil) + 2 for alluminmum tank + 5 for lung capcity. My lung capcity is probably bigger safty hazard than anything else becuase of the dynamic bouyancy changes if you get too comfortable and not pay attention (uncontrolled acsent or decscent from snowball effect from wetsuit and BC air). But I do use air as efficiently as the divemasters despite being a newbie (11 post-cert dives)

 

[Conchchowder]

Not sure where to place this.

But a LDS guy told me that there's recent study that if you're an overweight guy, you run the risk of not being allowed to dive anymore.Some organisations have banned guys who are above a certain weight/height/fat combo.

High fat percentage retains more nitrogen than normal divers.
I was adviced by the guy to always add 1 step on the Padi diveplanner for safetysake if I dive at a certain depth for a longtime. So if I dive a long time at 14 m...and that's the max depth. I should use one step further. So 16 meter when I plan the next dive.

But if I reach 14 m for just a short time ,but dive mostly at 10 m. I could safely follow the diveplanner.

Anyway seems reasonable. Anyone know about this new reaserch and it's findings?

OrganiSations? 16 METER? Without a location in your profile, divers in the United States and other countries may be concerned...but I assume you are a UK diver and the rules there are different. I'm 10 stone 8 (around 300 pounds) and nobody has ever questioned my ability to dive or susceptability to DCI. I add two personal factors to my Suunto D-9 and get wet! I also carry 18 pounds weight and add 12 pounds for my 3mm Instadry suit. I currently am .45 for my SAC rate..not too bad.