Sheena McNally is currently Canada's deepest woman, holding national records in 3 disciplines. Besides being a great athlete who, we are sure that, is on her way to achieving even greater things, Sheena is a passionate but cautious freediver, who develops herself at a constant pace, with no rush, being safe every step of the way. She is a prime example of how a healthy freediver should act, in order to progress in the sport, without hurting herself - or others - along the way.
In a recent interview with Tokushikai Canada, besides talking about her introduction to freediving and getting into depth competitions, she spoke about a few things that are worth noting. How did she go about depth progression? Are dive logs essential to keep? How important is breath hold in freediving? How much air can one store in one's body and how quickly does it get used? How has anaerobic exercising helped her bifins technique? Read on.
Getting Into Freediving
I’m originally from Alberta, Canada, which is the prairie, there's no ocean there, it's completely landlocked as you know. So, it all started with scuba diving, which was like the gateway drug into freediving, if you want to call it that. Initially, my parents forced myself, my brother and my sister to take swimming lessons because one of them can't really swim and we spent summers camping. We were around lakes and water and they were like “you guys have to know how to swim in case something happens”. I actually hated it at first but eventually i ended up really liking swimming. I would do the swimming lessons and did all the way up to lifeguarding.
I thought i would never try scuba because i didn't like the idea of being, i guess, stuck at depth, not able to just surface any time - to me that was quite intimidating. I thought i would feel claustrophobic but an ex-boyfriend's mother convinced me - she was a scuba diver - and she said to me “oh it's about breath control, it's about breathing long, deep and relaxed and controlling your buoyancy with breathing - it’s like an underwater meditation”. So, when she said this i was like “okay i hear you”, so i took a course which started in the swimming pool in Alberta.
In 2015 i decided to take a career break. The idea was to travel for six months and then make my way back to Canada and find another job. So it was just a chance to go do some scuba diving and see places that i hadn't seen.
I started the trip in an island called Utila in Honduras, it’s one of the bay islands. I was doing my dive master course and at the end of the three months i took - kind of almost on a whim - a freediving course, because i was walking past this like sandwich board sign on the street every day and the sign said “20 meters on a single breath”. It was for this freediving school and i remember just thinking over and over like “that's not for me, that's crazy, i like breathing, i don't like holding my breath”.
Eventually, someone who was doing this scuba dive training with me did the course and he was not like a very athletic guy, a bit of of a smart aleck as well. He did the 20 meters and he came back to the scuba shop and he was like “oh i did 20 meters, it was so easy, you know what we're doing here with tanks and scuba diving is for chumps and you guys are all chumps”! I remember thinking like “hmmm, so if this guy can do it, surely i can do this as well”. So i took this course, i got completely addicted the first morning in the water, even though i was nervous the day before doing the theory session.
How Were You Training Initially?
Before i got into competing i actually i stayed in Honduras for quite a few years and i became an instructor. I discovered that i really liked teaching people and i really liked watching them have this the same moment, that i had when i learned to freedive, which was just to discover that you're okay underwater on a breath hold. This was amazing and so i loved sharing this with people. The timing worked out really well, there was actually like a job opportunity right as i was finishing my instructor course, i took it, i was teaching and my own development as a diver was taking a back seat to that. But it was something that i was working on little by little. Like, any time we had a day off, the other instructors generally chose to spend that on land and maybe do some some partying, some catching up with friends, but i went out just diving for fun, for myself.
I just got really curious you know. I never thought i'd do 30 meters and then, once you do 30, it's like “okay could i do 40”. I never thought i'd do 40 and then you're like “okay once i hit 50 like for sure i'm done”. So it just went like that and i kept working on it just like little by little and not at all quickly.
The Event Which Led To The First Competition
One day we hired a boat to go to the north side of the island which is where you find more depth and myself and three other ladies, who i still call like my very good freediving friends, we pushed our buoy out into this deep patch and we had a handheld depth sounder. We were checking the depth and my personal best at the time was 70 meters which i had done in Mexico. I thought "i'm gonna try do like a one meter increase to 71". We set the line to what we thought would be about 71, it wasn't marked yet, which was our fault i guess. So, off i went, i was diving and i could kind of tell “this is getting to be a long dive”, so eventually i turned and came up.
When i came up and did my recovery breathing, i looked at my dive watch and it said 75. That number was significant for me just because in that form of freediving, i knew that the current Canadian record was 74 and it was set by a woman a long time ago, something like 12 years ago at that time, and it had been a world record.
So it was just this realization of looking at my gauge in disbelief like “i just did that”. It was certainly not easy, but it was doable and then was thinking “well, could i repeat that in front of judges”? That's what led me to sign up for the first competition, just one interesting experience.
I would say it just takes an awful lot of time with slow and careful progression and highly trained and competent buddies. Basically, once you start diving deep, it's just increasing the depth like a little bit. Let's say you did 70 - how was it like, how did you feel at the surface, what did your buddies observe, did they see you do anything funny, do you remember everything, how was the color of your lips, how was the effort? All these factors which you kind of have to try and get a good picture of after. And maybe if 70 was easy and if it was super easy, then maybe you increased to let's say 72, like just a small bit.
But let's say you did 70 and you kind of don't really remember like the last bit of your dive, where you don't remember your recovery, or your buddy says you had a little shake. Then it doesn't make sense to go deeper at all, it makes sense to pull back and repeat until everything is perfect. So, slowly and carefully.
Keeping A Detailed Dive Log
I have my own dive log where i write notes and keep various metrics. How i'm feeling during the descent, was i having urges to breathe or contractions earlier than normal, were they different than normal or were they pretty normal or were they later than normal? How did the effort feel on the ascent, were my legs or my arms burning, did i feel a lot of lactic, do i remember everything?
How you are at the surface is, i would say like, a really big metric, because actually most of the problems that are going to happen on a breath hold, they do happen at the surface and not under water. So, how was your recovery, did you feel gassed, do you remember your recovery, were you breathing properly or were you having some uncontrolled movement? So, yeah, tons and tons of metrics. I’m sure there's more, there's got to be dozens more things, but those are some of the things that i'm thinking about and looking at and writing about in my own dive log.
How Important Is Breath Hold In Freediving?
Most people think it's just about holding your breath. When people get into freediving, they're obsessed about whether they can hold their breath long enough or not, for a certain dive. As far as i’m concerned, right now, i'm not really even thinking about “oh is my breath hold gonna be good enough for this dive”, because your body will do absolutely everything that it can, to hold your breath when you're under water.
It isn't about holding my breath enough to do this dive, it's more about, i would say, your relaxation level before the dive ,but also during. Your ability to be comfortable being a bit uncomfortable, because some of the sensations you're gonna feel, especially as you get deeper, especially sensations related to high levels of co2, they're not comfortable, nobody likes them.
Your technique is also very important. The easier that you can move through the water, obviously, the less oxygen you're going to use and the less co2 you're going to generate as well. And I would say your streamlining as well plays a huge role. So, the better you can move through the water, the more efficiently, then the less oxygen you're using, the less co2 you're generating.
How Much Air Can You Store In Your Body And How Quickly Is It Used?
It’s very different from person to person. The way i think of it, i only have a guess of how much air can fit in my lungs, because i've only ever blown into a spirometer once for fun and even then, it doesn't know exactly how big your lungs are, it can just give you a guess.
But i also know that there's oxygen stored in our blood and i believe also in like the muscles and other parts of the body, so i don't know exactly. I know, if i put a fingertip pulse oximeter on, i know it can have a look and it can stay here at 99 or 98 or whatever, which is about as good as you're going to get. it means you're fully oxygenated. But in terms of how much do i use and how much do i need to use to do a certain type of dive, i don’t know. I guess you have to get to know yourself really well and it's really down to the experience you’ve got.
At the moment i do mostly high intensity interval style training, because it's got an anaerobic component and there's possibilities to get a lot of lactic acid going. Let's say for example i'm doing a lot of diving with my bifins, which is where you would kick with a certain style. As you get deeper, you need your legs to be kind of used to that feeling of burning, and being heavy and working anaerobically on the way up. And doing the interval training on land is one way that you can prepare for that.
I don't do at the moment really any breath hold training on land. There's been times when i have and that would be times when i'm away from the water for a couple of weeks or months. They call them co2 exercises or co2 trainings but at the moment i'm focusing mostly on fitness.