The Art of Buoyancy.By Gary Ward
Neutral buoyancy: A condition in which a physical body’s density is equal to the density of the fluid in which it is immersed. This offsets the force of gravity that would otherwise cause the object to sink. An object that has neutral buoyancy will neither sink nor rise.
We all know the importance of attaining neutral buoyancy when we’re diving, as it allows us to attain that complete weightless feeling, easily control our direction and attitude in the water, move more efficiently and of course conserve our air. However, attaining a neutrally buoyant position in the water is only half of the art.
In this review I will discuss with you those remaining elements which I consider integral to mastering….
‘The Art of Buoyancy’.
1) Visualization: Take a few moments to think about your dive before you get into the water. Use visualization techniques to relax and calm your breathing. Think about how you want to dive and focus on graceful movements. See yourself in your mind’s eye effortlessly gliding through the water. Think about being slow and smooth, graceful and efficient with your movements. This step is more important than many people give it credit for and can take anything from a few seconds to a couple of minutes. Visualization allows you to step back from the frantic hubbub of activity which can cause stress and tension before a dive and allow you to enter the water in the right frame of mind, relaxed and ready to enjoy the dive. A relaxed and smooth diver will be more efficient in the water, which means they will use less air.
2) Effective movement: I’ve never seen anyone win a medal or any plaudits for how fast they can dive a site or how quickly they can breathe through their air. Diving is a fun experience based activity and we want each experience to last as long as we can, to allow us to see and encounter as much as we can. To help us in this we have to think and act slow. We want to expend as little energy moving forward as possible. Use every element to our advantage, drift down current as opposed to swimming back to a fixed boat. Use light kicks to hold you in a back surge before using a bigger stroke to propel you with a forward surge, but more importantly take the maximum advantage of each kick stroke. A simple exercise to practice for this is to try to glide between each fin kick and think ‘Kick, kick, gliiiiiiiiiiiide’ if you’re using a flutter type kick.
3) Efficient fin kicks: Most divers start their life in the water using a form of flutter kick. This type of kick is signified by an up and down movement of the fins. This form of kick is the most natural to perform for most people, but the easiest to perform inefficiently. If we want to have forward propulsion in the water we need to try to use the largest and strongest muscle groups in our bodies. The muscles in our thighs are amazing in that they’re strong, effective and usually have good endurance too – after all, they’re the ones that allow us to stand up and walk! To make your fin kick efficient you should strive to use the power from your thighs to move forward.
Many experienced divers and dive professionals abandon the flutter kick and move to a wide frog kick. To complete the frog kick you’re using the big muscles in the back of your thighs (hamstrings) to create a single, double legged power pulse, and then you’re gliding forward as you prepare for the next pulse. It’s effective from a movement perspective and efficient from an energy angle too. It takes some practice to get used to, as you’ll initially feel as though you’re going nowhere. It’s worth persevering though.
4) Correct weighting: Using the incorrect weight is the number one reason why divers burn air. Most new divers tend to use too much weight. I have also seen many divers with hundreds of dives still using too much weight. Over-weighting has the advantage of allowing a lazy diver to descend really quickly and easily. But they then need to add a fair bit of air to their BCD from their tank to slow or stop the descent. Whilst they are diving, they’re lugging around a whole load of lead which is serving no purpose, but they’re making themselves more bulky/less streamlined by having to inflate the BCD to compensate. However, the most heinous element is still to come. Most divers wear their lead close to or around their waist. Carrying too much weight here has the effect of making your hips heavy in the water and giving you the appearance of heavy feet. At best this makes you very un-hydrodynamic meaning you will expend energy going upwards as well as forwards. At worst, you’re likely to have low feet and constantly be kicking the coral or marine environment. To address this issue, perform a buoyancy/weight check whenever you’re diving with new equipment, in a new environment or if it’s been a while since you were last out. To perform a weight check properly, you should use a tank which has already been used, as this will ensure you’re carrying enough weight at the end of your dive. You can complete the weight check at the start though. Get into the water with all of your scuba gear donned. With you regulator in your mouth hold a full breath (the only time you’ll be told to hold your breath). Let all of the air out of your BCD whilst holding your breath. If you have the right weight on you should drop below the water level and rise back up and float with the water at eye level. Do not kick or skull, but try to remain motionless. As you exhale fully you should start to slowly descend. If you’re carrying too much weight, you’ll sink whilst still holding your breath. If you don’t float at eye level, you should add a couple of pounds.
5) Trim: OK, so you’ve done the weight check and you know you’re now carrying the right weight, but look, you’re still ‘hips down’ in the water. This is because you’re probably still carrying all of the weight around your hips. The hip bone is the heaviest in the body, and so by sticking additional weight in the area will undoubtedly make your hips sink. You need to start to think about weight distribution to try to make you as flat in the water as possible. What this will probably entail is trying to move some weight higher up your body. This sounds reasonable, in order to stop our hips from sinking take some of the weight from there and put it higher up. It’s not that easy to complete though. I mean, can you just wear a weight belt under your armpits? Maybe, but it sure won’t be comfortable. Many modern BCD’s have trim weight pockets on the back, up near the tank cam-band. If you have them, use them to more evenly distribute your weight. If you don’t, it might be an idea to look at investing in a couple of small pockets that will fit onto the cam-band. Start by going for a 40/60 split of weight in your trim pockets and weight belt and seeing if you’re head down or hips down when you’re diving. Adjust as necessary until you attain that perfect, comfortable, horizontal position.
Practicing and mastering these techniques will start to yield immediate results. You’ll expend less energy fighting the water, you’ll burn less air thus enabling you to dive for longer and enjoy your dives more by being less tired. Consider focusing on your buoyancy by taking part in a PADI Peak Performance Buoyancy specialty course and improving your diving today.
If you want to find out more about PADI cources in Carriacou, you can visit our website at www.deeferdiving.com
Or if you are interested in becoming a dive guide and instructor yourself, you can find more information at www.deeferdiving.com/padipro.html