Friday, March 29, 2013
Follow Your Head :: An Easy Tip for Maintaining Good Buoyancy and Swimming Position
Thanks to Natalie Gibb
When I was learning to drive a motorcycle, I had the tendency to jerk the bike's handlebars to the left or the right when maneuvering around a turn. I had trouble turning because I tried to separate the motion of the handlebars from the rest of my body. I didn't understand that a proper turn involves the driver's whole body. Not only should the driver turn the handlebars, he should lean into the turn and look where he is going. It sounds simplistic, but once I learned this rule the bike would effortlessly go wherever I looked. Now that I teach diving, I see many divers making the same mistake that I made learning to drive a motorcycle - they forget to follow their heads.
The basic idea is simple - if a diver looks up and kicks, he is going to go up. This makes sense because by looking up, a diver orients his body into a feet-down, head-up position. Even a slight fin motion will propel him towards the surface.
The most common situation in which a diver make this sort of error is when clearing his mask. During the open water course, a student diver is taught to look up while breathing out through his nose to empty his mask of water. When this skill is practiced in the pool, the diver is usually kneeling and unable to kick. However, when floating mid-water, it is not uncommon for a diver to unconsciously kick while clearing his mask, propelling himself upwards. An easy trick to avoid this mistake is to have the diver cross his legs at his ankles or knees before looking up, preventing inadvertent kicking.
Divers also tend to orient themselves vertically when observing turtles, sailfish, and other creatures that swim towards or along the surface. On many occasions, I have watched a diver discover a turtle near the ocean floor, kick along with it for a minute, and then tilt his head (and therefore his body) upwards to enjoy the view of the turtle surfacing. More often than not, this results in the diver slowly rising towards the surface with the turtle until I call his attention to the fact that he is beginning to ascend. Once a diver knows that looking up to watch a creature above him has the tendency to make him lose his position in the water, he can take actions to avoid the problem such as deflating his buoyancy compensator or crossing his ankles.
When ascending at the end of a dive, divers are trained to swim towards the surface in a head-up position. In this case, this is a positive habit because it helps a diver to move efficiently through the water and allows him to make small adjustments in his buoyancy using his fins. Once a diver reaches the safety stop depth, however, a vertical position can make maintaining a constant depth more difficult if the diver habitually makes small fin movements. Again, awareness of the fact that a diver in a head-up position will move upwards with almost any fin movement will help a diver in this situation to keep his level in the water. Carefully monitoring a reference (such as a depth gauge, dive computer, or ascent line) is usually the best way for a diver to train himself to maintain a constant depth during a safety stop, despite a vertical position.
Once a diver understands that his body will follow his head, he can use the fact to his advantage. Although most buoyancy adjustments should be made with a diver's buoyancy compensator and lungs, small adjustments can be easily made by swimming. If a diver finds himself moving slightly up every time he starts to kick, looking down while swimming will help him maintain his level in the water.
Look up, swim up. Look down, swim down. It is a simple concept, but one that is commonly over-looked by beginning divers!