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Pushing the easy button on ascents

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I often ask divers if they feel any rise in tension as the bottom portion of the dive comes to an end and the prospect of the ascent enters their mind. It may reassure you that I have coached divers with thousands of dives who have answered "yes" to that question.

In fact, it's easy to see if your ascents are more stressful than they should be. If you hit the surface with any kind of elevated breathing rate, then there is something amiss. I"ll explain why shortly.

The ascent is just another part of the dive. It's not full of anticipation like the descent, nor the wonders of seeing the wreck or reef at the bottom, it's just the journey home, and yet people worry about it. To me, that says something is missing from their skillset. So here are three techniques to push the easy button when ascending from a recreational dive, and take the fear and stress out of ascents.

Step 1. Break the ascent into chunks

Climbers scaling the Eiger north face don't think about the whole climb. It's too much. Too daunting. They think about the first pitch. Sometimes, they think about the next move. It's an old psychological trick to overcome fear and the feeling of being overwhelmed. You see it everywhere in life. A runner focuses on the first mile, not the marathon. So instead of thinking about that 30 metre ascent, just think about ascending 3 metres to 27 metres. That's easy. You can probably see up 3 metres. So just go to 27 metres and pause. Then go to 24 metres and pause. And so on. With a bit of practice, you can travel up 3 metres in about 15 seconds, adjust your buoyancy and pause for 5 seconds. Then do the next 3 metres, pause, repeat. Hey presto, you are ascending at 9 metres per minute, which is around the rate that most computers base their calculations on, as well as most planning tools. 

This technqiue has a couple of benefits. Firstly, the psychological one. You are only moving 3 metres, then another 3, then another 3. Pausing each time. That's a lot less daunting that trying to ascending at the same rate all the way up. It also means you can use your computer to guide you. It's just 3 metres every 15 seconds, and then a pause. Finally, and this is an important one, it means that your ascent is very unlikely to get out of control. Remember that runaway ascents start slowly and then get faster and faster. If you pause the the ascent every 3 metres you are still keeping your computer happy, but also ensuring that your buoyancy never gets out of control. Think about it. If your last pause is at three metres, then you'll find it quite difficult to have a rapid ascent. All of a sudden, ascents are the gentle ride to the surface they should always have been.

Step 2. Use what you have.

It's challenging to control an ascent on a gauage or computer. You adjust your buoyancy, or rate of ascent, based on what your computer is telling you. Unfortunately, by the time the computer reports the change, and you are seeing it, it is way too late to adjust your buoyancy. There is a delay between you starting to move, or changing ascent rate, and the technology telling you about it. there is another delay in you adjust your buoyancy and anything happenning. The deeper you are, the more pronounced this delay is. So forget about those rate indicators, because what they are telling you is in the past. If you are going to use the technology to manage your ascent rate, use the numbers. Using the technique in step 1 you can simply move 3 metres as fast as you like, then wait until the seconds tick past 20. Then move as fast as you like 3 metres, and wait until the second hand goes past 40. This way you are moving at 9 metres per minute and using your technology effectively to manage your ascent rate.

Even better, however, is to use visual references, which have no lag and mean you can maintain far more effective control over your ascent. Watching a shot line go past is a great technique for maintaining a steady ascent rate. Watching a wall is even better. An SMB works well too, but avoid the tempation to "hang" negatively buoyant off it. Even if you are in open water with no SMB, there is likely to be a visual reference. Allow your eyes to defocus slightly. Except in the very clearest of waters, you will notice particulate matter in the water. These particles drift around in currents, so tend not to suddenly decide to ascend or descend rapidly. For all intents and purposes this makes them a stable reference in the water. If you see them relatively static in front of you, you are holding a nice safety stop. If they start going down, you are ascending. If they are rushing up past your head, you are ascending. You can see this far more quickly and easily than following your technology, so I tend to settle into a safety stop, then watch whats going on around me, just checking the gauge every ten seconds or so to confirm. 

Tip 3. Stop using your lungs

Your body has evolved over billions of years to be an extremely effective mechanism for distilling Oxygen from the air we breathe and, critically, expelling the Carbon Dioxide we create as a byproduct of, well, being alive. At normal levels, all Carbon Dioxide does is make you anxious enough to breathe. In fact, it's the level of CO2 that triggers the breathing response, not any lack of Oxygen. At elevated levels, and under pressure, CO2 is a stressor that causes your breathing rate to skyrocket, your heart to race, and your anxiety levels to go through the roof. Ever hit the surface out of breath? That's CO2. Ever become dizzy underwater? CO2. Ever found yourself puffing and panting underwater even through you are not working? CO2.  A splitting headache during the ascent or at the surface? CO2. The very best thing you can do to avoid a build up of CO2 is to just breathe normally. That's why divers tend to be more stressed on the descent and ascent, and relaxed on the bottom - because it is only on the bottom that divers tend to breathe normally. So here's the big secret. Use your buoyancy device. Don't try to accelerate or deccelerate an ascent with your lungs. Don't try and maintain a safety stop with your lungs. All that will happen is that the CO2 levels in your body will rise, your body will become stressed, and your breathing will become erratic. Once you are in that cycle it can be difficult to stop it. That's why you hit the surface out of breath.

So, let's avoid all that unpleasantness. Use your buoyancy device and resist the temptation to use your lungs to control your ascent or any safety stops. Mentally check in now and again and make a note of your breathing. If it's elevated, then focus on breathing normally. You will have been consciously or unconsciously compensating for a buoyancy issue. Once you breathe normally the issue will reveal itself and you can address it with your BCD.

So that's my three step program for making ascents easy. Break the ascent into managable chunks, create a visual reference if you can, and stay calm and relaxed by avoiding the use of your lungs for buoyancy control. As a final note, it's probably worth me pointing out that the single best thing you can do to feel better after a dive is slow the ascent down in the shallows. Once you have completed your safety stop, don't rush to the surface. This is where the pressure gradient is greatest so you want to take your time. Ascend slowly - I go from six metres to the surface at one metre per minute - and the difference in how you feel, and how tired you are, will be noticable and dramatic. It's also a fantastic drill for improving your buoyancy control.

Have fun, and dive safe.

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Gareth Burrows is a GUE Instructor trainer, and a personal diving coach for recreational and technical divers of all levels, specialising in improving buoyancy control, trim and stability, in-water confidence, and ascent management. He has trained with PADI, TDI, IANTD and GUE as well as serving as a DO in a BSAC branch. He has been diving cold water wrecks in Europe and around the UK for over a decade, and can usually be found diving out of Brighton, Portland or Plymouth. He is qualifying later this year as a cave diver and looking to become a GUE tech1 instructor in the 18 months. He has trained or coached hundreds of divers from newly qualified open water divers, to course directors and technical instructors.