In this video we are focusing on trim and in the end I’m going to be giving you my one single biggest piece of advice for getting your trim down absolutely pat. But first, I want to answer the 6 most common questions that students have for me about trim.
What do we even mean by trim?
In the simplest terms trim is your body position in the water. You can think about it as scuba diving with good posture and when we’re underwater we want to be in as hydrodynamic of a profile as possible and the reason for this is because that means every kick we make is going to be the most efficient. Trim also covers things like streamlining your equipment configurations to make sure you don’t have a huge amount of drag being created which obviously makes kicks less efficient. There’s a reason they don’t make submarines in the shape of a world decorated Christmas tree. Why? It is trim important.
As we said in other videos in the ‘Dive like a Pro‘ series, trim is one of the four core fundamental skills of scuba diving together with breathing propulsion or finning and buoyancy control. So the thing with those four skills is they are all interconnected. If your trim is off, how does that affect your buoyancy your breathing and your propulsion? Well as I already mentioned bad trim means that you’re gonna have to kick harder to overcome drag. If you have to kick harder that means you’re going to have to increase your breathing rate which means you’re going to consume your gas faster. How does trim affect buoyancy? Well, trim covers things like the correct positioning of weighting so that you can use the minimum amount of weight you need which means you’re passing the less gas through your buoyancy and so on and so forth. All of these four skills are completely knitted together and if one of them is out of whack chances are the other three will be as well.
So what position should I be in?
Well, the best position for a scuba diver underwater is to have a torso as horizontal or parallel to the surface as possible. You want a slight curve in your back so you can angle your hips forward but keep your chest and the rest of your torso in a nice flat position and then if you’re using the frog kick style you’re also going to want to have your thighs in the same plane as your torso with a 90 degree bend at the knee and a 90 degree bend at the ankle so when you frog kick you’re getting the maximum amount of efficiency and the rest of your body is nicely aligned. If you’re using the flutter kick style, that’s perfectly acceptable, but you want to make sure that that midpoint where your legs are crossing each other is where your both your legs are horizontal and again in line with the torso.
Where should your arms be placed?
Well I see a lot of divers who just tuck their arms in and fold them across the chest there. It’s not the best practice but at least you’re streamlining and not creating excess drag. I prefer to have my arms out in front of me like this for a couple of reasons. Number one there’s no air in my arms and there’s no area in my legs so that means I’m counter balancing my lungs nicely and the second reason is that I’ve got all my instruments here. I’ve got my compass, I’ve got my computer so I can reference everything at a glance. Plus, I mean if we’re being honest, you just look bad-ass.
Your head should be in a neutral position but tilt it up slightly so you can see where you’re going obviously but there shouldn’t be a need to crane your neck. The slight bend in your back should lift your chest enough that you can hold your head in a nice comfortable position.
One of the common mistakes divers make when considering their trim is not thinking about it as a skill that actually needs to be worked on and refined and also not testing their trim.
How do you test your trim?
Well it’s very simple, all you do is get nice and shallow and close to the bottom but without touching it obviously and hold a hover. Just hold a hover in one exact position and if you’re not pitching or rolling then your trim is probably okay and it means that the weight is evenly distributed around your body. Once you’ve got that hover under control give a couple of kicks. Did you go straight forward, remain at the same depth and in line with the way that your body is facing or did you veer off to one way or the other or go up or go down in which case your trim is off somewhere. Go back make adjustments to the placement of your way. Maybe shift some accessories around if you’re carrying a lot of gear with you and try and get as balanced as possible in that hover position. But the challenge people have when judging their own trim is it’s not really a measurable thing. You can get the feeling you can run that test and so on but it’s not like breathing where you can look at your gauge and see how much you’re actually consuming.
How you can actually manage your trim a little better?
I think another mistake people make when trying to refine their trim is not considering their equipment as part of it. They focus on getting their body in the right position but don’t actually consider that their equipment choices play into how their trim comes out. For example, a back plate and wing is always going to serve you better than a big bulky jacket style BCD and then you’ve got things like your accessory mounting such as where is your octopus hose being routed, where is your knife being mounted, your real and your SMB. If you’re down there looking like a one-man band, your trim is never gonna get to where it needs to be regardless of how good your body position is so consider making all of your equipment choices with streamlining in mind.
Even your choice of fins plays into your trim. I have several different sets of fins that I use for different types of diving such as negatively buoyant fins, positively buoyant fins, neutrally buoyant fins, just to make sure that my legs stay in the right position. Obviously if I’m in a dry suit I want a nice heavy pair of fins to keep my legs down so I don’t go inverted. If I’m travelling and I’m just diving barefoot then I want the lightest possible fins I can so I’m not two-tailed.
When it comes to trim that’s a real pro level tip. One pair of fins does not cover all styles of diving so yeah you’re gonna have to make some different gear choices.
What can I do to perfect my trim?
I think I’ve packed this video with quite a few hints and tips already for you but the honest answer is just practice, practice, practice, practice. There is no easy answer, there is no shortcut, there is no magic wand. I’m sorry to have to tell you that but the only way you’re gonna get better at trim is doing a dive refining your setup, refining your waiting, refining your body position and then doing another dive and keep going and keep going and it’s a constant work in progress. I don’t know if there is such a thing as perfect trim. I know people who have better trim than me and it’s something I’m always working on even as a dive professional.
This kind of brings me to my single biggest piece of advice on the subject: it is to use an action camera. It is an absolutely essential tool to help you improve your trim and your body position in the water. It’s very hard to have that out-of-body awareness to see what you look like and it’s just a great tool for that purpose. I use one all the time with my tech students as I want to make sure that they know what they look like in the water and you should do the same for yourself. Get yourself an action camera, give it to your buddy and have them swim around you in 360 degrees in all planes and that way you get a really good sense of how you are looking underwater. Then just hold a hover and have them swim around you and then you can review the footage and make changes based on what’s actually happening.