[Note: I was in New Zealand for a few days for work-related business, and at the moment I am wrestling with a particular blog post that requires more attention and editing and fancy pictures than I can generally churn out on short notice, so here is something I prepared earlier. -KN]
Before getting my dive ticket, I agonised over whether I was “diving fit”. I spent most of my childhood and adolescence being more-or-less sedentary, and had this notion in my head that people had to be extremely buff gymsters in order to be able to SCUBA dive.
This is… not the case. Of course, the more fit you are, the better: diving will be easier. Walking down the pier wearing weights and tank will be easier. You will be more efficient with air. You may be asked to carry other people’s tanks, and thus earn their eternal gratitude and numerous blackmailing opportunities. Your tendency to get fatigued and dehydrated and develop some form of DCI (decompression illness) will be reduced.
Fitness isn’t, as a concept, well defined. It is better to apply fitness to a particular goal.
Take yours truly. I am not spectacularly fit. I go to gym a few times a week, I do my weight training, I spend a lot of time on flexibility, and at the moment I am trying to get through the Zombies! Run! 5k training app. I am probably stronger than most of my cohort (age/sex/etc.) and have an advantage in terms of muscle mass. But if you watch me running, you will be appalled. I am slow. I am ungainly. I have bad feet. I have hypermobile joints. I am, basically, horrifying to watch. My podiatrist referred to me, in slightly awed tones, as “the most flaily runner I have ever seen.”
In short, I am not running fit.
Fortunately, I am diving fit.
To be basically diving fit means that you can accomplish the following things:
- You can swim 200 metres (any stroke; I like backstroke) without stopping. You can take as long as you like to do this.
- You can tread water for ten minutes (this can be quite soothing).
- You can lift and carry your own tank (it’s okay to need help getting it on. That shit is heavy and awkward right there. Park benches, fence posts, retaining walls and dive buddies are popular aids for this process).
- You can walk around wearing the unit and the weights that you need to descend (more on that in a moment).
- You can climb ladders onto boats and piers wearing the unit and the weights.
A standard sized 12L steel tank weighs slightly under 14 kgs, although this varies depending on the manufacturer and how much air is actually in it at the time. For most people this is a bit uncomfortable, but not a major obstacle.
The real problem comes down to weighting.
If you are diving in warm, tropical waters, you may not need thermal protection. It’s warm and pleasant, so you might dive in a lycra suit or, if you’re not concerned about jellyfish and fire corals, a bikini. Bikinis and lycra suits are not particularly buoyant, so you won’t need much weight.
If you are diving in cold waters (Melbourne. Sigh), you need thermal protection. I dive with at least a 7mm neoprene semi-dry wetsuit. These are, to use a technical term, very floaty. In cold months, I wear a drysuit. These are even more buoyant, since they don’t take on water. You don’t sink in this gear; you just bob around on the surface of the water. That’s not diving. That’s just very expensive snorkelling.
Because of this flotatious thermal protection, I need to wear more weight. The amount of weight you need to use is reduced as you get more experience in diving: you relax, you breathe more slowly, you learn to control your buoyancy. I am down to about 7 kgs in my 7mm suit, which suits me just fine (I used to wear about 10 kgs). That means that, including the tank, I’ll be wearing over 20 kgs strapped to my person, not counting the wetsuit itself and other accoutrements; and let’s remember that it is not strapped on in a particularly ergonomic fashion. I can walk in that without getting exhausted, but it is a workout not to be sneezed at.
In my dry suit I wear about 11 kgs of lead – so over 24 kgs in total. That makes a difference. Again, I can walk in that, but I do so very slowly, and have a breather before I descend (note: descending while out of breath or with an above-resting heart rate is not a great idea. You’ll guzzle air on the way down).
This is me. I am of a very average build. You might think that if you put on weight, you’ll have to carry less lead – because, naturally, you’ll be heavier.
Unfortunately (and believe me that I curse this), fat is positively buoyant in water. So even if you are very heavy on land, if that heaviness is fat rather than muscle, you will need more weight. I’ve known people who wear upwards of 20 kgs of lead alone, not counting their tank. This doesn’t mean they can’t dive; on the contrary, people of all sizes and shapes can master our not-so-ancient art, since people of all sizes and shapes can be diving fit.
But it does mean they have to be very strong if they are going to do cold water diving, because they are going to be walking around wearing that gear. You don’t usually park on the pier. Generally, you walk at least a hundred metres from the carpark to the water entry, and frequently it’s further than that. Not only are you walking, though; you’re bending down to pick up things if you drop them, or put your fins on if you are doing a jump entry; you’re helping your dive buddy get their own gear on; you are still bending and moving and doing heavy work, it’s just that now you’re wearing a metric fuckton of weight. You need to be able to do these things and help your buddy do these things if they get stuck.
This is not meant to be discouraging. I found it embarrassingly difficult to do anything in full kit at first. You get stronger, and it gets easier, and then it feels fantastic. It’s better to go in with your eyes open, though.
This is the main reason why diving requires fitness – for the most part, it’s not the actual diving and swimming. You wear fins when diving, and most of the time people swim quite slowly so they can look at things. In fact, you are encouraged to be relaxed and breathe slowly; diving is exercise, but it’s not supposed to be work when you’re under water (unless you are actually diving as part of your employment, which may involve diving in crappy conditions). The biggest risk is before and after you get in the water.
My recommendation for “stay dive ready” exercise is weight training focusing on back, legs and core work. Those are the muscles you use to handle your gear, get it on, walk around in it, and swim against current if necessary. Cardio is obviously a net benefit, but that is always true, and it’s not everything. I’ve seen numerous divers with excellent cardio fitness struggle to get onto the boat at the end of the dive because, when gravity reasserts itself, their glutes and hamstrings start to give out.
That’s right. You need a strong arse. You can climb a ladder wearing weights, but you need to take it slowly and use the big muscles.
I nearly met my match on a particularly awful ladder in Albany, Western Australia. It was an old, slightly rusted ladder hanging from the town jetty, and only the bottom rung was in the water; this meant I had to hook my knee over it to even get leverage. There was a moment where my supervisor looked at me and offered to take my weight belt so I could get up the ladder. I am nothing if not bloody-minded and managed to get my feet under me and straighten my legs (not without some cost and limping and very sore muscles for the following couple of days), but it was touch and go for a moment. This was also back when I was wearing a lot more weight, and, not coincidentally, I had less muscle strength than I have now.
Essentially, if I can do it – even at the cost of some wincing and whimpering for a day or so afterwards – it is pretty much achievable for most people, barring some particular circumstances.
There are a few conditions and situations that make SCUBA diving a spectacularly bad idea, and some that merely make it slightly more tricky, including but not limited to asthma and diabetes, as well as some temporary advice. I am not a doyenne of diving health or general SCUBA safety, but I plan to do some research and post some more general and basic information on the above conditions and general Thing You Should Not Do but which some people do anyway (much of this would be covered in an Open Water course, but refreshers are always good). If you want a heads up in the mean time, I suggest contacting someone listed among the South Pacific Underwater Medical Society (www.spums.org.au).