Freediving & Diabetes Info Request

[Cliff Etzel]

I have a friend who is looking to learn to freedive. The challenge is that this person is Type 1 Diabetic (Insulin Dependent) and has been so for over 30 years.

I have done a fair amount of research as it pertains to Diabetic Protocols with the scuba agencies plus the research that DAN has done on this topic. The concensus is that as long as the diabetic diver has not had any major episodes or complications such as hospitalization, severe hypoglycemic episodes, is in good physical condition, that being certified should not be an issue with the understanding that strict adherence to Diabetic protocols be made. SSI and the BSAC both have documents and medical advisers as it pertains to scuba and diabetes.

Now the challenge of freediving with diabetes. Since there are several things associated with diabetes - high blood pressure, possible problems with the eyes, and Kidney failure, all seem to indicate that diving would be a no-no. Yet with these said protocols in place, there have been numerous "closet" scuba divers out there - some of whom are Instructors whom have been diving for years without any mishaps.

I am looking for specific information regarding how blood shift (due to concerns of blood circulation with diabetes), effects on blood pressure (specifically on the kidneys and eyes), and any other freediving physiology information as it pertains to freediving with diabetes.

I would especially like to hear from any forum member who is an MD or exercise physiologist who can elaborate in detail about this.

If needed, you can PM me and we can discuss via email.

TIA,

[efattah]

Although I don't have the qualifications, from my experience I would see no serious problems for a diabetic freediver. If the blood sugar is very low, a BO might occur very slightly earlier.

Perhaps MD Frank Pernett could offer his opinion.

[Cliff Etzel]

Hi Eric - the one concern my friend has is in regards to blood pressure changes and how it would affect the kidneys. My friend is VERY strict about blood sugar levels and tests throughout the day. From what I have gathered so far, I do not see any issues from what I have learned so far but I could be wrong. I do hope Frank chimes in and can give some medical insights on this topic.

[Fitz-Clarke]

Your friend could possibly free dive, but he must be aware of two major risks: (1) Hypoglycemia (black out from low sugar). His sugars must be reasonably stable, including with exercise, and without recent dramatic swings. He should check his sugar prior to beginning diving each day, and check periodically if diving for a prolonged period, and take extra food if low. Dive buddies should be vigilant for black out, and know how to respond if an episode of hypoglycemia occurs (protect airway, administer glucose or glucagon). Hypoglycemia might be difficult to distinguish from hypoxia on surfacing, but hypoglycemic symptoms generally do not resolve without sugar adminstration, whereas hypoxia usually corrects itself rapidly on the surface with a few breaths. (2) Coronary artery disease. This is the only secondary complication of diabetes that can impact significantly on diving. He should be free of known CAD, or be able to pass an exercise stress test if there is any history of CAD. Retinopathy and kidney complications are not likely to be problematic for diving unless advanced. If he has peripheral vascular disease, he probably has some CAD, and should not dive due to risk of heart attack or leg cramps (claudication). Normal blood shifts of free diving are not an issue unless there is significant vascular disease. Blood pressure tends to go up to varying degrees in free diving due to combined effects of immersion, hypoxia, and peripheral vasoconstriction, but this should not be a problem unless his hypertension is poorly controlled. Medications might be an issue. Check with his physician. Whether or not your friend should free dive depends on stability of diabetes (sugar control), degree of secondary complications, maturity of attitude, exercise tolerance, and willingness to accept a potentially small increased risk of black out if sugar inadvertently falls low.

John Fitz-Clarke, MD, PhD
Halifax, Canada

[Skywalker]

Not a doc here but confronted with Diabetes Patients again and again in my Ambulance Services. I totaly agree with Fitz Clark and just would add some details he propably thought off them but just did not form then in letters.

Out of my point of view there should be at least one dive buddy with him who is able to test your Friends blood sugar (this can be learned in like 5 mins)

I also would not see a problem with the kidneys or eyes regarding freediving and possible hight blood preasure during freediving. The Eye and Kidney Problems or complications are mainly effects which are related to chronical wrong blood sugar (high or low) or lots of Hypoglycemia or Hyperglycemia events over a longer period of time.

I also recommend a blood sugar test withen short time before the training is supposed to start and maybe in between if the training is supposed to be longer (but maybe it would be a good idea to set a limit for training times just to prevent the blood sugar from dropping to low)
As a normal freediver may just get exhausted and tired after long trainig your friend propably already suffers from dangerously low blood sugar.

One thing is for sure Diabetes is nothing to play with as it affects almost all of your body if you are handling it wrong even directly your braincells and the neural network in general.

Robert

[Cliff Etzel]

I have discussed this information with my friend (in reality - my partner.. )

She and I have discussed the pro's and cons and she feels that she needs to set up an analysis of her sugars during gym training first - that way she can better understand what will set her into low blood sugar. Once she has a baseline, begin pool training. She will probably invest in a fingertip pulse oxymeter to see how vasoconstriction and elevated blood pressure affects her while in the pool doing statics (One hand out of the water using the oxymeter). If we determine she is good at that point, begin shallow water training and eventually set her max depth to 10 meters as a starter. In reality, that is probably all she would really want to go to anyways. I'm the one who want's to dive to 10-30 meters while shooting video so it will be a summer of testing.

I wonder if there are any medical professionals that freedive who would be interested in this very modest experiment for freediving and diabetes...

[feign]

Hi Cliff,

Something else you should consider. What is your friends hypoglycemia awareness? A complication with longstanding Type 1 diabetes (particularly poor control) is the loss of early awareness of signs of hypoglycemia. Because freediving can be a a significant energy burn, this could be a hazard. A dive float with simple sugars on board could be a useful safety measure.

Also, essentially as it has been discussed, hyperglycemia (high blood sugars) is bad news for the vascular system. It can be classified into microvascular and macrovascular damage. The microvascular stuff like the retinopathy in the eyes and macro like the large vessels in the heart (coronary arteries). I see that their is a likely small, but a possible risk with the transient hypertension seen in freediving and I believe Fitz-Clarke was referring to this as well.
If your friend has poor macrovascular health eg. coronary artery disease or other large vessel disease, then hypertension will increase the risk of a clot resulting in something such as a heart attack, stroke, or limb ischemia. We see this in any one who has vascular disease - hypertension is a risk factor for clot formation. I agree that the kidneys and eyes will likely not be a major concern, unless they are in poor health now as these problems are really a chronic process of longstanding hyperglycemia.

lee

[Cliff Etzel]

Actually her awareness is quite high - she has lived with this condition for 30+ years. If anything, she is, almost too aware - she constantly monitors her levels all day long. Hence the reason for asking in the first place. It is a complicated issue it seems and only she can make the decision as to which way she want's to go with this.

I do appreciate the excellent advice regarding this issue - I have shared with her the responses so far and she is glad to see some of her fears are not as big as she made them out to be - while others she is very aware of and seeing that reconfirmed has helped her find a place of acceptence as to whether to move forward on this...

[feign]

It sounds like everything is going forward ok, but just to clarify my post. By awareness I was referring to the physical symptoms that can creep up on someone, between sugar level testing, particularly in physical exertion scenarios. Does she know without checking if her sugar is low by such things as lightheadedness, tremor, sweating, weakness etc.

lee

[Cliff Etzel]

Yes - she is VERY aware of the signs - but I think for her she has some fear regarding the fact that freediving - although graceful and minimalistic, does require a higher level of physical fitness and her fear is she would find herself in a situation she would rather not be in...