A recent article in X-Ray Magazine had a look at different ways to prepare for a dive and how they affect decompression sickness.

In other sports it is good practice to ‘warm up’ before the game. It reduces the risk of injuries. Divers don’t do any stretching exercises before the dive but there are some common practices that divers follow to reduce the chance on decompression sickness.  As part of a three year project called PHYPODE researchers had a look at some of these ‘preconditioning strategies’ and the effect on bubble forming in your body.

Drinking water

It’s probably not surprising that the researchers found that hydration before the dive reduced the chance on DCS. Drinking lots of water in a short time doesn’t help. It’s best to drink small amounts over a longer period. They also found that the amount of fluid loss during a dive is related to the bubble forming in your body after a dive. Sounds to me like you get bent from peeing in your wetsuit! Another reason not to do that! Off course the serious conclusion is that hydration AFTER the dive is just as important as before.



We have always learned – and taught our students – that heavy exercise before and after a dive would increase the risk of getting decompression sickness. Actually it turns out that doing some exercise before the dive reduces the chance of DCS. In hyperbaric chamber studies divers produced less bubbles after a test dive when they had done some exercise 24 hours before the dive. Another study tested the effects of cycling for 45 minutes, two hours before a dive in the ocean. In this study divers that did some ‘warming-up’ also produced less bubbles, both with moderate and strenuous exercise. The researchers don’t really know why this is. How much exercise should you do? How long before the dive? We don’t know that yet.


Recently some Belgian scientist (who else?) studied the effects of eating dark chocolate before the dive. They found that it has a positive effect on the vascular endothelium and that may reduce the chance on decompression sickness. Now, I don’t really understand what a ‘vascular endothelium’ is but if you use difficult words like that I’m sure you’re very smart. And if you tell me I should eat lots of chocolate before the dive I’m more than happy to believe that! Timing is critical however! You should eat your chocolate two hours before the dive.

You can read the full article in X-Ray Magazine #85

Asia Scuba Instructors Blog is written by Course Director Marcel Jansen. Asia Scuba Instructors runs PADI Instructor Courses in multiple locations around Asia.

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