How much weight should a diver use? How much is too much or too little to maintain proper posture, balance and air consumption? How do you adjust for a new wetsuit? Simon Pridmore discusses weight issues and offers tips and advice.
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Helga was on the eighth day of a long liveaboard trip across Indonesia. The diving had been superb, and she was having fun and feeling relaxed.
She backrolled into the water, dropped down to the seabed at 24m and swam over to a coral head to see what she could photograph. The first thing she spotted was a tiny, beautiful, bright-red frogfish pretending to be a sponge. “Got you,” she thought. “What a great start to the dive!” She spent a couple of minutes taking pictures from various angles until she was satisfied that she had the right shot, then turned to find her husband, who would normally be hovering close by. There he was. She flashed him an OK sign but, instead of responding in kind, he pointed at her waist. She looked down, wondering what the problem was and, at first, she could not see anything wrong. Then she saw what he had noticed.
She was not wearing her weight belt.
Her initial thought was that she should go back up to the tender boat and retrieve her belt, but then it occurred to her that she was already at 24m. What would be the point of ascending to get a piece of equipment to help her descend if she was already on the bottom and doing just fine?
She had been wearing 3kgs of weight on her belt. This was 1kg more than she would usually wear, because she had begun the trip with a brand new 3mm wetsuit and was aware that, being new, this suit would have more positive buoyancy than her old suit, which had been compressed and recompressed during a couple of hundred dives over the years and had consequently become thinner, less able to keep her warm and less positively buoyant too.
Helga’s husband slipped a 1kg weight off his weight belt and passed it to her with a shrug as if to say that was the best he could do. He raised a thumb, asking her if she wanted to abort, but Helga shook her head. She popped the weight he had given her into a zippered pouch on her harness and indicated that they should just continue the dive.
This they did. They had a great time, ascended after the prescribed 60 minutes and Helga managed the safety stop without any difficulty at all. She was a slim, petite lady, she always used less air on a dive than the others in her group and usually surfaced with at least 70 bar in her cylinder.
The weight debate
Back on the tender boat, Helga told the group what had happened. “Well, you have obviously been wearing too much weight!” said one person. “Maybe you don’t actually need any weight at all?” said another, indicating that Helga had not even noticed she had left her weight belt behind until her husband pointed it out.
A third diver decided that this was an apt occasion to deliver a short speech on how: 1) it was always best to wear as little weight as possible because carrying too much on your belt affected your posture in the water and pushed your legs down; 2) adding air to your BCD to compensate for the excess negative buoyancy lifted your head up and made you look like a seahorse; and 3) extra air sloshing around in your BCD made it hard to keep your balance and all that rocking and rolling increased your air consumption.
A few heads nodded in sage agreement. That seemed to sum it up.
However, a fourth diver begged to differ. “Not so fast,” the diver said. “While all that might technically be true in general, it certainly did not apply in Helga’s case.” The diver mentioned how they had all been diving together for a week and they could all agree that even when Helga had been wearing her belt with the extra weight, her posture and stability in the water were pretty much perfect. And she always had more air left at the end of a dive than any of them.
There was more nodding. These, everyone acknowledged, were all good points too. The conversation moved on.
Observations
Helga had noticed three things during her almost-weightless dive. The first was that she had not added any air to her BCD at all, the second was that her lower back had started to hurt during the second part of the dive, which was unusual, and the third thing was that she had found it more difficult to stay completely still while she was taking photographs.
She concluded that, after 20 dives in her new suit, she evidently no longer needed to wear more weight to compensate for its newness. She had managed to do the dive with just the 1kg her husband had lent her, yet she had missed the sensation of being rock-solid and “centred” in the water that she usually felt. She also guessed that her lower back pain might be associated with her subconsciously arching her spine towards the end of the dive, as her cylinder gradually emptied and became increasingly positively buoyant.
Conclusions
Her conclusion was that, while she had shown that she could accomplish a normal dive using only 1kg of weight and was even able to descend wearing no weight at all when her cylinder was full, this was not sufficient justification for changing the way she dived. Yes, the advice that divers should carry less weight on a dive to improve their posture, balance and air consumption was entirely valid, but this did not mean that a diver should therefore carry less weight than they needed.
Less was not always best. As far as Helga was concerned, her previous experience had told her that 2kgs was what she needed to be completely comfortable and relaxed on a dive, and this latest dive had just confirmed that this was the case, rather than the contrary.
She continued to dive with 2kgs with her 3mm suit and tried to remember never to forget her weight belt again.
