This question should be the first thing any diver asks themselves as they prepare for any dive, regardless of depth, duration or environment. Every diver understands that the underwater environment is a hazardous place to be, but we equally know that these risks can be reduced through good training, preparation and the use of well-maintained equipment. The one piece of equipment that is often overlooked is the body we take underwater.

Scuba diving is one of the fastest growing sports in the UK and through training agencies such as PADI and BSAC the underwater world is becoming accessible to people from all backgrounds, ages and fitness levels. Although we all sign medical declaration forms stating we are fit to dive, how many of us actually understand what that means? Ticking a box to say you are dive fit doesn't automatically turn the odds in your favor.

There are lots of different reasons to maintain a good level of physical fitness as a diver and in some cases it is even a prerequisite for the level of your diving certification. However beyond the obvious benefits of being agile enough to maneuver in the heavy and cumbersome equipment required to dive safely there are significant health risks involved with diving whilst unfit.

Being fit can significantly decrease your air consumption rate whilst diving. There is nothing worse than diving with a buddy who has extremely poor lung capacity and for whom moderate exercise forces them in to a breathing marathon. When underwater every diver wants to conserve their air to maximize the length of time they can stay down. Increasing your fitness level will have a massive positive impact on the rate at which you consume your air supply.

Furthermore fat is extremely buoyant, and although it seems counter intuitive, the fatter a diver is, the more lead weight they need to strap to themselves to allow them to descend. Carrying an excessive amount of lead shot around on a dive is uncomfortable and can reduce the divers' underwater range of movement. I have seen some extremely unfit and overweight divers requiring nearly 20Kg of lead just to allow themselves to get the under the water.

The one thing that no diver really wants to talk about is the chance of a coronary incident happening underwater. Heart attacks are bad at any point in time, but underwater the likelihood of a positive outcome is far less. The Divers Alert Network (DAN) reports that heat attack and cardiovascular disease are a rising cause of fatalities in dive circumstances, especially in divers over 40.

Lots of people naturally assume we breathe oxygen underwater, which is in the main not the case. Recreational divers simply breathe compressed air; the same stuff we breathe whilst on dry land, it's just compressed in to a cylinder so we can take a fair bit with us. It comprises roughly of 21% oxygen and 78% nitrogen. When we dive to depth our body tissues absorb nitrogen. Fatty tissues absorb nitrogen quicker than lean tissues; they are also far slower to release the nitrogen when we surface. Nitrogen released from fatty tissues in to the blood stream is a major contributing factor to Decompression Illness or the bends as most people know it. Although I am simplifying things significantly the long and the short of it is, that the more fat you carry the more you increase the risk of subjecting yourself to a bend.

Not only will being fit significantly reduce your chance of a diving related injury, or worse fatality, it will hugely increase your enjoyment of the sport. Diving isn’t an elite sport for elite athletes, it is an easily accessed sport that should and is enjoyed by the masses. However it is very important to understand that the very latest regulators, BCD, dive computers and dry suits, whilst looking great and being technically advanced won’t do anything to prevent a serious injury from occurring if you are not fit to dive.

Regular exercise, a balanced diet, good hydration and regular sleep are the essential tools every diver should ensure are the first things they put in to their dive bag. Without these you could be putting yourself at unnecessary risk.

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