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Freediving Training Blog / Journal

The following details my regular training and experiences with freediving.

[03/03/05]: Lung Volume Spirometry test

Before training in the pool, I had an opportunity to perform a lung volume spirometry test (with a handheld computer device). Basically, one breathes out completely, places the device on your mouth, and then breathes in as fast and full as one can. Then, after a pause, one breathes out as fast and as fully as one can.

Why Lung Volumes are Important to Freedivers

A key ratio for freedivers is the ratio of total lung capacity to residual volume. At the surface, a diver will increase one's lungs to the total lung capacity (or more, through packing). The minimum volume of air that is contained in the lungs after a complete exhale is the residual volume. One will generally have a hard time breathing out this much air, and the empty sensation can be quite unpleasant.

During a dive to depth, the surrounding ambient water pressure acts on any airspaces within the body and causes the overal lung volume to decrease. At a depth of 30 metres (100 ft), the lung volume has been reduced to a quarter of what it was on the surface. For most people, the ratio of total lung capacity to residual volume is 4:1. For the average person, reaching 100 ft in depth will cause the lungs to have compressed to the "theoretical" minimum volume, the residual volume. For years, it was believed that one could not withstand pressure (or compression) below this amount, otherwise the lungs would collapse. This has been proven untrue, as the body has a number of other mechanisms (see the Mammalian Dive Reflex, blood shunt, thoracic filling, etc.) which help prevent this from happening.

The depth in which one reaches their residual volume (ie. through compression of the total lung volume) is a theoretical limit, and it is also the point where one typically gets pressure contractions (like on my first dive below 130ft).

For freediving, one would typically want the ratio of total lung capacity to residual volume to be as high as possible, thereby increasing the theoretical depth at which the lung volume has reached residual volume.

The Lung Volume Spirometry Values

Basically, the device attempts to measure a number of important pulmonary functions as shown in the table below:

VCVital CapacityLitres The volume change of the lung between a full inspiration and a maximal expiration
FVCForced Vital CapacityLitres The volume change of the lung between a full inspiration to total lung capacity and a maximal expiration to residual volume
FEV1 Forced Expiratory Volume Litres Volume of air that is forcibly exhaled in the first second
FEV1% Forced Expiratory Volume % Volume of air that is forcibly exhaled in the first second expressed as a percentage of the total forced exhale volume
PEF Expiratory Peak Flow Litres/sec The maximum flow generated during expiration performed with maximal force and started after a full inspiration
MEF25 Maximal Expiratory Flow @ 25% Litres/sec Maximum expiratory flow when 25% of the FVC remain to be exhaled
MEF50 Maximal Expiratory Flow @ 50% Litres/sec Maximum expiratory flow when 50% of the FVC remain to be exhaled
MEF75 Maximal Expiratory Flow @ 75% Litres/sec Maximum expiratory flow when 75% of the FVC remain to be exhaled
MMEF Maximum Midexpiratory Flow Litres/sec The average expiratory flow over the middle half of the FVC
PIF Peak Inspiratory Flow Litres/sec The maximum flow generated during inspiration performed iwth maximal force and started at residual volume

My Lung Volume Results

Getting my results, I was quite surprised. My [forced] vital capacity was 6.56 litres. This seems a little large for a person of my height, possibly as much as 20% larger than normal. My total lung capacity could quite possibly be close to 10 litres, once the residual volume is added in.

VCVital Capacity6.36 litres
FVCForced Vital Capacity6.56 litres
PEFPeak Expiratory Flow11.30 litres/sec
PIFPeak Insiratory Flow12.23 litres/sec
RV Residual Volume ~ 3 litres?
TLC Total Lung Capacity ~ 10 litres?

Is this good? Is this potentially bad?

While this might seem great for freediving, there is a concern that my freediving training has possibly caused an increase in my lung volume. I am going to get a full pulmonary function test to see what my residual volume is. If I have managed to increase my lung volume (ie. stretched), then it is possible that I have also increased my residual volume as well. This can certainly be a concern, as one is not sure of the lung term effects of doing such a thing. I will certaily be anxious to see the results.

The full residual volume test is done in an enclosed airtight chamber. While sitting in the chamber, a mixture of inert helium gas is injected into the chamber, and the mixing of gases allows one to measure one's total lung capacity through examing the gaseous composition.


[02/27/05]: Western Regional Competition: Dynamic Apnea without Fins

I was intending to forfeit my dynamic apnea without fins performance and instead try for another dynamic apnea with fins performance. This way I could adjust my warmup routine slightly and see if I could get a clean dynamic. I wasn't as worried about forfeiting the points in my dynamic no fins event because I had already messed up the static and original dynamic with fins.

Unfortunately, Tom Lightfoot derailed my plans by telling me that I have to get some points today! (Apparently it doesn't look good to come away with zero points, except on your first competition!) So, I reluctantly reconsidered my strategy. Instead, it looked like I'd have to do a dynamic apnea without fins, and then I'd have a "personal record attempt" slot to retry my dynamic apnea with fins later.

Considering I have NEVER done a dynamic apnea without fins before, I didn't like the sound of this. So, I spent the next ten minutes trying to get ideas from Tom and Kirk Krack on how the arm pull and kick is supposed to work. This also meant that I wouldn't really have a good chance to re-evaluate and tune my dynamic apnea with fins target. I would have less than 40 minutes between my two performances.

  • Warmups - Again, all of my warmups were done dry, without facial immersion. It looked like things were feeling good today — I finally had enough time to get relaxed, not worrying last-minute about whether or not I should use 2 or 4 lbs like yesterday.... or so I thought!
    • Ventilation - 2:00
    • Hold - 2:30
      No contractions.
    • Ventilation - 3:30
    • Hold - 3:00
      No contractions.
    • Ventilation - 5:00
    • Hold - 4:00
      One small purge just before the hold. One contraction at 3:45. Deliberately tried holding them off a bit, felt heart rate dropping during this time.
    • Gear up at poolside - 2:00
      This time I allocated two minutes to move from my relaxed static area to the competition lane and put on my weight belt and mask.
  • Final breathe-up - For most of the breathe-up I tried sitting on the poolside, feet dangling in the water, being as motionless as possible. This would eliminate some of the big movements I had to do previously when getting up from a lying-down position. Unfortunately, I suddenly realized that my weight might be wrong (as I wasn't wearing my monofin this time). In the last ten seconds before going, I made the decision to drop my weight belt. I had visions of being too negative and scraping my legs along the bottom of the pool, so I elected to ditch the belt. Thinking back, this was probably a mistake, but I didn't have much time to decide what to do.

    After yesterday's mistake with too much breathe-up, I thought I'd try to reduce the purging from one minute (about 14 purges) to only six purges, at about one minute out. This was followed by thirty seconds of relaxed breathing. At my start time, I took a full breath and then packed ten times.
  • Dynamic - 61 m Dynamic no Fins - Personal Best! (in 1 minute 23 seconds)
    Never having done dynamic with fins before, I found it somewhat awkward. It was hard to resist the urge to cut short the glide phase of the stroke. It seems like three seconds of glide might be best for the pull phase. I had completely forgotten the technique demonstrated to me for the kicking, so I ended up doing more of a dolphin kick than a breast-stroke kick. I was also much too bouyant and swum in a downward-angled profile. Next time I will need to wear 2 lbs at least.

    Looking at the underwater video afterwards, I could see a number of things that would need to be improved besides the kick and bouyancy. My hands were too open during the pull, not getting as much thrust as closed fingers would have given. Similarly, when I went to bring my hands back up overhead, I was not slicing them against my body in a streamlined fashion, which would have helped.

    My contractions had started somewhere around the 30-40 meter mark, and I decided to simply come up safe than try to push it and risk another DQ. Coming up at 61m, I felt fine and realized that I could have probably made the 75m mark. But, knowing that I was going to try another dynamic apnea with fins after this attempt, I didn't want to exhaust myself much.

The silver lining in all this was that I came away with a third-place ribbon for the dynamic no-fins :)

Mandy-Rae with her
well-deserved ribbons!

New National Records broken

The competition saw some impressive new records being made. Peter Scott made an incredible 104 meters for a new Canadian national record. Mandy-Rae Cruickshank also put in an amazing swim with her 100 meter performance, setting a new Canadian womens national record. Congratulations to both of you!

Redo of Dynamic With Fins for Personal Record Attempt

Realizing that I only had another 30 minutes or so before my next dynamic (a competition slot for personal record attempts), I had to quickly rework my warmup routine, and decided to throw it all out except for a 4:00 breathe-up, 3:00 hold and then the same 7:00 breathe-up as I did for the dynamic apnea without fins.

My heart still racing in my chest, I tried to relax for my warmup hold, and the 3:00 ended up being really uncomfortable. Contractions were starting close to 2:00, which is the earliest they have ever come for me. I knew immediately that this last dynamic attempt would probably be poor today. It's obvious that I need more time to recuperate from my last performance or mindset.

Nearly ready to announce that I was going to bail on my record attempt, I decided to go for it anyways.

  • Final breathe-up - Again, I spent seven minutes on the edge of the pool and dropped in at the 1:30-to-go mark. Did 6 purge breaths at one minute to go and resumed my relaxed breathing. At ten seconds to go, I started getting bad cramps in the arches of my foot within the monofin, and I wiggled my feet around trying to relieve them. Uh oh! Fortunately, the cramping abated just in time for my zero-second count. A big breath and ten purges later, I pushed off.
  • Dynamic - 113 m Dynamic with Fins (in 2 minutes 13 seconds, but Airway and LOMC violation)
    I should have made a conscious effort to remind myself that all I wanted to get was just over 100m, but instead I obviously decided to push on, making nearly the same distance as yesterday. And again, the same mistake! When I was surfacing, I gave a couple quick kicks with the monofin, which sent me right out of the water, only to fall back under briefly. Peter Scott pointed out the problem with my surfacing technique and gave me some great hints at how to avoid this easy disqualifying error. I am going to have to focus on returning to the surface with a single arm-pull instead of the kicks. But, of course, with all of the breathe-up and previous dynamic attempt, I was probably not in good enough shape to do the 113m clean. I should have bailed out earlier, but didn't.

Given a similar experience, it still looks like I should reduce my breathe-up even more. Going from 14 purges to 6 purges is still not enough to keep me within the range of a clean performance. It's obvious that unless I consciously remind myself to exit at a pre-specified distance / time, I tend to push on with will-power until I am at my limit. I need to allow my blood CO2 to increase to my breaking point earlier, so that I have a clear exit point. Right now it's too easy to get to my limit.

What this means is that I might try dropping the six purges down to a single purge breath. I am pretty confident that this single change might allow me to not only get a clean performance in, but also increase my distance / time.

[02/26/05]: Western Regional Competition: Dynamic Apnea with Fins

Today, I did my dynamic apnea with fins. As I have been performing my dynamics without a wetsuit, I am experimenting with dry static apnea for preparation, instead of wet. I was hoping that this would work out for me (unlike last night's static apnea!). I had announced a minimum of 50 meters, but was aiming for 100 meters.

Well, now that I've done my attempt today, I come away with mixed emotions...

  • 114 meters (in 2 minutes 8 seconds)!!! A new personal best in dynamic apnea! My previous best was 102 meters. This would have placed 42nd in the AIDA 2004 world ranking, so I guess I should be reasonably pleased. Maybe with a little more work on the breathing, I might have a chance at going for my goal of last year's Canada national record (Peter Scott's 125.1m, before Eric Fattah pushed it to 136.6m)! At least it gives me something to shoot for. Somehow I don't think Eric or Peter have anything to worry about!
  • But unfortunately (when am I going to get this right?! ), I got a technical disqualification for allowing my mouth to come in contact with the water while I was in my 30 second judged recovery interval. This was my first time competing with a monofin, so I completely forgot about making sure that my airways were well above the surface during the recovery period. I am still new to the monofin, and so I forgot how much more work it would be to tread water high enough. With each kick of the monofin I would bob up and down, and unfortunately one of these caused the disqualification (known as a "submerged airways" violation). It also looks like I was on the verge of getting hypoxic LOMC, so I'll have to reduce my breathe-up.

Even though I'm going to come away from this competition with a zero score (ie. last), I did learn a fair bit from today's attempt.

  • Weighting - I decided to use 2 lbs of weight to get me neutral. In my previous dynamic apnea attempts in training with the monofin, I found that I have been somewhere between neutral and positive while wearing no weight belt. Mandy-Rae Cruickshank previously indicated that my swimming angle indicated that I was under-weighted, and trying to counteract with an awkward profile. This was my first try with weight, and I think 2lbs was perfect. No chance in getting a surfacing violation this time!
  • Calvin doing the
    dry static warmups
    Warmups - All of my warmups were done dry. The dry statics felt fine and I think this will work well for me going forward. No facial immersion.
    • Ventilation - 2:00
    • Hold - 2:30
      No contractions.
    • Ventilation - 3:30
    • Hold - 3:00
      One contraction at 2:50, but I could have held it off.
    • Ventilation - 5:00
    • Hold - 4:00
      Contractions started at 3:30 and the hold was pretty easy.
  • Final breathe-up - Spent seven minutes trying to breathe-up calmly while lying down on the edge of the pool deck. At 1:30 left, I hopped in, and started 60 seconds of purging. For the last thirty seconds, I continued with relaxed breathing until my final breath. On my final breath, with 8 packs, I felt my blood pressure drop temporarily (due to the pressure in my lungs acting on the blood supply) and I was ready to go.
  • Swim - Contractions started somewhere near the 75m mark, I think. I resisted the temptation to sprint even up to 100m. Once I made the 100m mark, I started feeling the signs of my limit coming up, and so I surfaced some distance after making the turn. Coming up, I felt near the end of my limit, and I'd have to make some changes in my routine before I'd consider doing the same distance with the certainly of making it clean.

Perhaps the most important aspect of my experience from both the static apnea and the dynamic apnea has been that I am doing too much breathe-up! The fact that I can hold through to samba is indication enough that I'm starting off too hypocapnic. Talking to Eric Fattah afterwards, he made the very interesting statement (to paraphrase):

If you can hold through to samba, then you've done too much breathe-up.

If you reach your breaking point first, then you've not done enough breathe-up.

The best breathe-up is one where you have found a balance on the curve between these two scenarios (ie. you were just about to give up and this was just before you would have had a samba).

Given everything I've now experienced, I think it's time to reduce my breathe-up, drop the number of purges, and instead make the apnea more unpleasant, with the trade-off in increased duration. In addition, I will try to focus on making an absolute minimum of movements in my final breathe-up, and not try the in-quick, out-slow breathing I've been doing until now (for reducing the heart rate). If I feel up for it tomorrow, I might try to re-do my dynamic apnea attempt and use only a bare minimum of purging.

[02/25/05]: Western Regional Competition: Static Apnea

Feeling a bit nervous about my lack of preparation for the static (due to me being sick during training and not getting a chance to experiment with my routine), I realized that I was not going to put in a good performance (compared with where I was at at the end of last season). A big part of the problem is that I've been trying to find what time I'd be able to get a clean performance. So, I figured that I'd be cautious and come up at 5:00, giving me about 15-20 seconds of time from my last attempt's LOMC.

Doing my warmups, things were feeling good, although the pool's water was very cold this time (probably due to an upcoming swim meet). Although I lost my diving slate with my routine just before the competition (oops!), here is what I did:

Sharon about to start her
static apnea target
  • Facial Immersion - 5:00
  • Ventilation - 2:00
  • Warmup hold - 2:30
    No contractions, but they would have started just after 2:30
  • Ventilation - 3:30
  • Warmup hold - 3:00
    First contraction, around 2:50.
  • Ventilation - 5:00
    One purge breath, to make the hold a little easier.
  • Warmup hold - 4:00
    Felt reasonably fine, contractions started around 3:30.
  • Ventilation - 7:00 - The mistake...
    Here's where I knew I was going to have a problem. During my breathe-up, I started feeling a little hypocapnia (low carbon dioxide), as there was a slight tingling in my arms. My slow breathe-up must have been either too deep, or too fast. Probably ended up being more like purging. This tingling started even before I started my real purge breathes. Knowing this, I realized that I would probably have a poor performance because the Bohr Effect would mean a stronger binding of Oxygen to the Haemoglobin, reducing gas exchange.
  • Target hold - 4:48 with "subtle" LOMC
    The hold was feeling good, although I did have a slight warm, flushed feeling and I could feel the tingling signs of hypocapnia. My diaphragmatic contractions started around four minutes but I still felt fairly relaxed. But after around 4:30, my contractions were getting pretty heavy and they seemed to be fast enough to indicate that it was time to come up.

    Coming up before the five minute signal, I took my mask off (way too quickly, an obvious sign of guilt, says Kirk Krack!), did six recovery breaths and gave the OK. But, feeling a little on the edge (and remembering the hypocapnia at the beginning), I was not overly shocked when I saw Tom Lightfoot give me the red card (disqualification). Chalk this one up as a learning experience. It looks like I'm going to have to revisit my breathe-up to ensure that I don't end up dropping my carbon dioxide too low. This is only going to hurt my performance like it did.

Getting myself ready for the dynamic competition on Saturday, I feel that I might have a chance to put in a reasonable performance. Unlike my static apnea routine, which obviously needs fixing, I think my dynamic apnea is hopefully going to be more reasonable.

[02/24/05]: Last minute warmup routine decisions

During the day, I was still struggling to decide whether or not to use my old warmup routine, or continue with the new one (that I used the last couple sessions). There were two main differences that I was experimenting with:

  • Two warmup holds vs three?
    Most of last year, I had been working with three warmup holds, and on each hold I'd see that my body was getting more ready for the main hold. I could tell this by the fact that the contractions were starting later and later after each warmup, without any additional purging. Ideally, one would continue to do this until one saw little additional benefit, and then start the main target. I had been trying to use two warmups instead to just get on with it, so that I wouldn't be as tired physically (ie. cold) or mentally.
  • When to start purging and how much?
    After talking to a few people, I realized that this recent trial of doing one minute of purges a minute and a half before my start time is probably not working for me. This is probably too much purging and because of the Bohr effect, my blood is probably hanging on to the oxygen too tightly to give it up efficiently. The only positive with this additional purging was that my contractions were starting very late (ie. four minutes).

    Previously, I had been starting 30 seconds of purges (7 total) at the 30 second mark, followed by one or two normal breaths before my final breath. With this other style (one minute of purging 90 seconds out) that Kirk Krack seemed to favor, an idea is to give some time to reduce your heart rate after the purging. Unfortunately, I don't think I can get efficient gas exchange after 60 seconds of purging. Luc Gosselin suggested to me that the need for the recovery period to reduce the heart rate doesn't seem to be that useful as your heart rate will drop quickly anyways.

Talking to Luc Gosselin about an hour before the competition, I eventually decided to revert back to the three warmup routine, provided I didn't find myself getting cold. I also decided to go back to the 30 seconds of purging just before my final hold.

[02/22/05]: First static target... too many changes too late

Finally had a chance to try a target static before the competition starting this Friday (Western Regional Competition ). Started with a 5:00 facial immersion, 2:00 ventilation, 2:30 hold, 3:30 ventilation, 3:00 hold, 5:00 ventilation (2-3 purges at end), 4:00 hold, 7:00 ventilation (started purging at 5:30, ended purges and started relaxed breathing at 6:30), then target.

Well, I reached 5:19, but I was a little shaky at the end, so I'm not going to count it. I was really hoping that I'd be able to push around 5:30 this time, but with all of the changes in my warmup routine and the fact that I've had a bad cold for the past week, I guess I shouldn't be surprised. One thing that did surprise me, however, was the contractions. For my 2:30 hold, the first one came at around 2:30. For the 3:00 hold, the first contraction was around 2:45 and that was it. The 4 minute hold felt good, and in fact I was thinking that perhaps I should have just gone for it instead of trying for yet another warmup. I have a feeling that my body was ready during the 4:00 warmup hold. The contractions didn't start until somewhere after 3 minutes.

On my target breath-hold, my first contraction started at just before four minutes! I have never had my contractions start this late, and I am attributing it to the fact that my final breathe-up has one minute of purging followed by 30 seconds of relaxed breathing. I used to start purging at 30 seconds and would stop at about time minus five seconds, but I am no longer doing this. The main reason for the change is that I think the purging is increasing my heart rate substantially just before the hold, and the 30 seconds of relaxed breathing should help bring the heart rate back down a little before the final breath.

Another change I've made recently is the incorporation of 3 warm-up holds before my final target breath hold. Previously, I was only doing 2. I only went back to 3 because I figured that my body might need the extra time to help trigger the mammalian dive reflex. But, I am starting to think that I might not need this (I think I might be getting more tired physically and psychologically otherwise) and should revert back to a quicker warmup.

So, thinking towards the competition in three days time, I don't feel prepared from a warmup routine perspective. Thanks to having a cold for the last week, I haven't had a chance to do any other static targets, or experiment with my routine. As a result, I only have this hold to go on. So, I am probably going to play it really safe and just go for a five minute hold, and not let myself go past this point. It's no longer difficult to push past this point, but obviously I hit a point of no return where I can no longer judge a safe exit time. My cue to come up seems to be when my contractions involve more of my body and I end up making more of a noise in response to my diaphragm's contractions.

Hopefully, I'll make my five minute breath hold target nice and clean to start off the season. It's a little depressing that it isn't as high as my last competition's time (5:16), but obviously I have too many variables to change and there is no longer any time left. After talking to Kirk Krack and Mandy-Rae Cruickshank tonight, I think I'll probably end up ditching my last warmup and extending the second one. In other words, do a 2:30 hold, 3:30 hold then the target. I hope this works!

[02/17/05]: Bad time for a cold!

Unfortunately, with my late nites and lack of sleep, I eventually fell prey to a cold from a coworker. I never get sick (almost ever), but when I'm run down and don't get my rest, that is the time that it can hit me. Couldn't come at a worse time as I am trying to get my practice targets in for the upcoming competition. So, I will be taking the week off, which will leave me with only one practice target (static only) before the competition. Oh well.... Better to do that than to stay sick until the competition.

I can only imagine the thought of what it would be like to do a static apnea target in competition for over five minutes with a nonstop running nose! Running noses and diving masks don't go well together! Pair that with the fact that you're not allowed to splash your face once you're finished your hold (otherwise you'll be disqualified), and I can see an awkward situation waiting to happen!

[02/15/05]: First dynamic in ages... tried dry statics for prep - a new PB!

Tonight I was intending to do our usual cardio session with Mandy-Rae again, but it seemed that everyone was more into doing dynamic apnea targets. So, not having my wetsuit with me, I decided to do some short statics to get warmed up, but do them dry. I knew that if I were to do wet statics without a wetsuit, I'd be cold by the time I got to start my dynamic. It's really easy to get cold doing statics without a wetsuit!

This was the first time that I had tried a dry static in preparation for my dynamic apnea (usually I do them wet, or in the water for full effect). I started without any breathe-up and ended after having two or three contractions. This was around 3:15 for me. Had a clear mind, feeling pretty good this time. My first contraction must have started just before 3:00, which is good considering I usually get them around the 2:30 mark for my first wet static.

A 3 minute breathe-up and I start my second practice hold. Holding through about a minute of contractions and I cut it off at 4:15. I reason that it's not worth depleting my body tissues of oxygen too much prior to my main breath-hold, so I don't like doing more than around 4 minutes in my warmups. By now I was feeling a little cold (because I wasn't wearing a shirt or towel during the statics), and I decided to jump in the water early to hopefully warm up. What a mistake! Two minutes before my announced start time and I'm shivering like crazy! I can't stop shivering during my breathe-up! This can't be helping me!

I end my breathe-up with forty-five seconds of purging, and then fifteen of relaxed breathing. A full breath and about 8 packs and I'm off. No wetsuit, no weight, and it seems that I'm pretty close to neutral buoyancy. I'd like to wear a couple pounds next time to ensure that I don't break the surface near the end of my dynamic. Swum four and a half lengths underwater, giving me about 112 yards, which is 102 meters! A new personal best! During the swim, I had forgotten that this was a 25 yard pool, not a 25 meter pool, and so I stopped after what I thought was a good distance. If I had known that it was only yards, I would have pushed through to the end of the length. Oh well! I think contractions started sometime near the end of the fourth length, but it's hard to say (as I don't consciously think about them during dynamics).

Next time, without the shivering, I imagine that I should be able to push on for a new record!

[02/13/05]: First target training for upcoming Competition

Western Region Competition is coming up in two weeks, and I have been nervous... mainly because I have done no targets in 8 months!

Tried to do my first static apnea hold in 8 months. Just wanted to start off easy (to get my confidence back) with a 4:00, starting with 2:30 (my normal start for contractions), then 3:00 and finally 4:00. I told myself if it felt fine then I'd continue on. Unfortunately, I didn't do a proper target breathe-up as I was treating the 4:00 as another warmup (only 5 purges). So, I got 4:54 quite easily (although I didn't have much left), without a lot of the negative thoughts that I used to get. With a proper breathe-up and more purging, I fully expect that I should have no problem reaching my previous times fairly soon. Mandy had told me that her first statics back were always the easiest, partly due to the lack of expectation... I think she must be right.

As an aside, Sharon has also registered for the Western Regional competition, and will only be doing statics. I think she should be fine for a 4:30 hold, assuming that she gets some wet statics out of the way beforehand.

[02/04/05]: Improvements...

With regular training, I am starting to see some improvements. With the open water simulation exercise, I am now getting one length (25m) underwater, 30 second underwater hold, then swimming two and a bit lengths, which is another 60 metres or so. My breathe-up for this is now experimenting with 60 seconds of purging ended with 2 slow breaths. After doing this my heart rate is quite high, so I am going to have to try purging earlier and following it with 30 seconds of relaxed breathing. I also wonder if I am purging too much, as I am not getting contractions at all during my swim, when normally I would expect them. This certainly feels nicer, but it removes one of the indicators I get to gauge my progress. Instead, I have to rely on other sensations to tell me when I'm done.

[01/17/05]: Regular Training again. Monofin great!

I have had the luxury of being able to train with Kirk Krack and Mandy-Rae Cruickshank a couple times a week now for the past month or so. As it is still cold outside, it's all been pool training, but I can see the benefits already. In particular, the cardiovascular workouts and the negative pressure dives have been working for me.

I am now very comfortable with my carbon fibre SpecialFins monofin, and am very glad that I bought the heavy (hard) stiffness version. The feelings I had earlier of floundering around are definitely fading away... I think my monofin technique has certainly improved, although it looks like I still have to work on putting equal power into my upward stroke.

Trying to assess how things feel differently, it looks like my dynamic apnea attempts with this fin should be better than what I could accomplish with my plastic bifins. One of the exercises that we have been doing was to simulate an open water dive. This involves taking a breath, swimming 25m, holding 30 seconds under water, and then seeing how many lengths one can swim after that. This mimics pretty well what one would experience in an ocean dive, with the swimming down to neutral bouyancy, freefall while negative, and then the swim up to neutral again. I have been seeing progress, and last time I managed 25m, 30 second hold, and then just over 50m. This was with 14 purges. However, I noticed that I was still not getting contractions at the end of this, so I will probably reduce the purges down to 10-11 next time. I would like to get contractions to help ensure that I can have some physical signals to judge where my limit might be.

The negative pressure diving in the pool has already made big improvements for me. Whereas before I used to feel very uncomfortable with an empty-lung dive at the bottom of the pool, I am now seeing that discomfort start when I am doing a full exhale with 2-3 reverse packs and then the dive. What I've noticed is that now, after the full exhale with 2-3 reverse packs, my body all of a sudden relaxes and allows the negative pressure to act on my chest cavity without discomfort. When I then go on to 4-6 reverse packs, I feel no crushing sensation whatsoever. Kirk suggests that this is the blood shunt in action. More blood is pooling in the chest cavity, allowing the cavity to withstand greater pressure. Similarly, my diaphragm is probably getting more relaxed, and is simply moving up inside the chest cavity.

With the negative pressure diving (in the pool's deep end, only about 15 feet), on a full exhale with 6 reverse packs, one is simulating significant depth, and the fact that I don't feel the crushing sensation (what Tom Lightfoot calls "squishy") is a good sign that my real open-water diving is probably going to see some benefit soon. I have also reached the limit of what I can do with reverse packing with my throat. I am now experimenting with what Kirk Krack has been showing me: big reverse packs with the throat, followed by lots of little reverse packing using the tongue against the soft palate to create a vacuum.

[12/11/04]: Getting back into it after wedding

Following the packing injury, I took a lot of time off around my wedding. In fact, my wedding coincided with the World Freediving Championships here in Vancouver, Canada. What bad timing!

Now starting regular pool training across the winter time. Training in the ocean is too cold, not because of the water temperature, but in getting ready / getting out in the cold air.

I am now feeling much better with the monofin (I now have my own Specialfins Carbon Mono! in heavy stiffness), and I think I've finally started to get the hang of moving around with it. Dynamics feel stronger with the monofin. Negative pressure dives (pool simulation) don't feel good yet, but it's been a while since I've been doing anything like this.

Worried about how my first statics are going to be. It's been a long time, and they've always been tough mentally for me. Right now, I wonder how long it will take me to get back up to the 5+ minute breath-holds again. Done a couple 3-minute breath-holds, and they felt OK, but I haven't been holding through the contractions for long (lack of motivation right now).


[06/14/04]: First Time Monofin

Tonight was the first chance I've had to swim with a monofin, and Kirk Krack lent me his Specialfins "Peter" Medium. Unfamiliar with them, I had an embarassing first few attempts to tread water, but soon it started to feel more comfortable. Next, I tried some simple dynamics to test out the stroke. First few 25m lengths, it was taking me 11 kick-cycles. It seemed that I was neglecting the back-stroke, so I worked on a continuous motion involving the back-stroke as well. This brought me to 9 kick-cycles to make 25m, which felt more reasonable. Just to gauge how things felt, I swum 75m with the monofin, and it felt surprisingly good.

On my bifin 100.6m dynamic, I was getting contractions somewhere just before 50m, and then swimming the next 50m in contractions. With the monofin, I wasn't getting contractions until after 50m, making me think that I could already feel some increased efficiency in the different stroke.

I think I could like them!


[06/13/04]: An Omen for Monofins?

In an attempt to see how my recovery was going, I went out for a day dive at Ansel with the usual group. Having spent no time in the last month practicing any techniques or stretching, I knew that I would have to stay shallow. I did several dives around 30m, and felt OK. Although I could get full breaths in on land without discomfort, the wetsuit causes me to expend more lung-muscle effort to get the same expansion, so I did feel a small amount of discomfort which prevented full breaths. It seems to be getting far better. I'm guessing that my chest is back to 90% now.

Getting a chance to experiment in a non-competition environment let me try two things:

  1. PowerFin efficiency: I discovered that with my new bifins (WaterWay Power Blades), it takes my 10 kick-cycles to get to 17m, whereas it took me 12 to get to 15m with my CressiSub Gara 2000 LD's. So, there is probably more efficiency at play here. I really love(d) my new PowerBlades (short-lived, as you read below).
  2. Mouthfill technique: I also wanted to experiment with trying the mouthfill technique at 15m. Previously, I had been stuck around the 40-43m mark due to a complete vacuum in my mouth (no air left for equalization). Even though I had enough air for the dive, my equalization was stopping me. This time I tried a gentle blow at 15m to fill my cheeks, and suddenly I realized that that's all it was going to take. At 30m, I felt like I had so much air left for equalization, I knew that this was going to allow me to get past my 43m barrier. Unfortunately, I will have to wait until everything heals up first.

Feeling pretty good about things, I was taking off my new PowerBlades at the back of the boat when one bounched off the back into the water. Oh no! With the fin within arms reach, I was just about to jump in to grab it when the captain yelled for me to stop (the prop was in gear). While waiting for him to shut off the prop, I had to sit and watch the yellow shape slowly descend into the deep. I jump in, trying to find it, and so does Brent, trying a valiant no-fins recovery for me. Unfortunately, my new PowerBlade is sitting in several hundred feet of water now

Mandy jokes around that, "You just wanted to have to buy a monofin!" Hah... Not really, but I guess maybe now!

I have actually been considering monofins ever since people started indicating that going 40m+ with bifins tends to get scary with the lack of propulsion at the bottom turn. There seem to be two popular choices for me: WaterWay Monofin or Specialfins Monofin.


[06/01/04]: No Nationals this time

A really tough decision for me, but I realized that this injury is not going to fully recover before the Canadian Nationals. So, I decided to pull my registration. I suppose the only positives I get from this are:

  1. Lots of time to improve before next year's Nationals.
  2. Won't get in as much trouble for freediving when I'm supposed to be wedding planning!

Instead, I will be safetying for the Nationals in June 25-27th, which will still allow me to play a small part, even though I know it will be emotionally painful for me to watch!

[05/25/04]: A Second Visit to the Hospital

Took 5 minutes to get out of bed without feeling like I was going to tear something. My injury had started to feel better over the previous few days, and then all of a sudden it got far worse. Worse enough that I was concerned that perhaps my injury was worse than I had thought. I visited the hospital again, and saw another doctor who insisted on me getting an exhalation XRay, primarily to check for pneumothorax or pneumomediastinum. They asked me to breathe-out fully for the XRay, and so I did. Ten minutes later, the doctor comes back concerned -- he says that he is concerned about possible fluid in my lungs as he saw a large amount of "crowding" in the XRay. So, he then asked for an inspiration XRay. As painful as this one way, I tried my best, and the doctor came back to tell me that everything was OK. The "crowding" he say in the expiration XRay was simply because I exhaled much more than most people would, giving the unusual appearance.

In summary, again I confirmed that I had no pneumothorax or pneumomediastinum. It was likely an injury to the costal cartilige and a strained ligament in the chest. Time would be the only means to heal this one.

One somewhat embarassing part of my stay within the hospital was being hooked up to the pulse-oxymeter. Waiting for hours in the hospital leads one to some pretty relaxed breathing. In fact, I was curious how low I would bring my heart rate through relaxed breathing. Mistake! Next thing I know, the machine I was hooked up to started sounding off alarms, and flashed a large red banner across the screen saying "* APNEA *", one that stayed on the screen for the nurses to see. Didn't take long before a nurse ran over to see if I had stopped breathing! Oops!

[05/17/04]: Packing Injury

Injured my chest from packing. This injury has been the most frustrating injury I have ever caused myself. Basically, it happened like this:

I was trying the ATRC blackout-tolerance test (published on, and it involved quickly standing up while packing to max. I normally pack 15 times after a full breath. This time, without any warm-up packs I packed 18 times, trying to feel the full effect of the test. Even though I passed the test and didn't BO, I had no idea what I just did to my body.

The morning of the 19th (two days later), I was in searing pain. I could not move at all without a sharp pain in my chest. Scared that I had perhaps ruptured some alveoli and damaged the delicate tissue of the lung, I was very worried. So, I went to the emergency ward at the hospital where I was XRay'd for pneumothorax and pneumomediastinum. Fortunately, both tests were negative, indicating that this was just perhaps a muscular or connective tissue injury.

[05/07/04]: Western Regional Competition - First competition!

My first competition, and I learnt a lot from the experience! The best part about it was the comraderie amongst all of the competitors.

My results:

  • Static Apnea - 5:16 clean
  • Constant Ballast - 40.5m in 1 minute 18 seconds
  • Dynamic Apnea - 100.6m in 2 minutes 00 seconds

My goals were:

  • Static Apnea - 5:15, announced minimum of 4:15
  • Constant Ballast - 40m, announced minimum of 40m
  • Dynamic Apnea - 80m, announced minimum of 50m

In the last training wet statics, I was getting 5:45, but with LOMC. So, for the competition, I elected to get a clean run by reducing my target time substantially. I hope to improve my breath-up so that I can get 5:45 clean (wet).

The constant went well, although I need to work on a mouthfill technique. Currently, I am only retaining my mouthfill from the surface which seems to last me enough equalizations to ~ 45 m. I intend to work on a mouthfill at around 20 metres to give me more range, and attempt to still keep the soft palate neutral.

In the dynamic, I ended up being too bouyant (with 4lbs, no wetsuit) and incurred a 10 point penalty by having my heels break the surface at around 90 m. Next time I plan on using 6lbs, which should also allow me to improve my kick style to be more forward-directed (instead of part-downward). Due to the need to counteract positive bouyancy throughout the length, my kick cycles end their motion much too vertical (and induce drag).


Previous experiences

I only started this log after my injury, as it immediately eliminated all of the progress that I had been making. Until this point, I had been making regular and continuous progress, and was excited to compete in the Nationals and hopefully the World's if things still held together.... Unfortunately, I would ruin any hopes of that!

So, to keep myself from getting depressed over this, I thought I'd share my warnings of how this injury affected me, and give myself a platform to chart my progress in trying to get back to where I used to be.


Reader's Comments:

Please leave your comments or suggestions below!

I am a freediver based in Flic en Flac, Mauritius. Maybe we could get together?

You can contact me through my website
 I'm 15 years old and i've gotten really interested in freediving. I've been practicing static (dry) and my record is 5 min. In dynamic apnea i can swim about 50m. what should be my next step?
 Thanks for sharing the video! That wreck is really nice (I believe it is called the "SATIL", and is at 80ft)
2010-09-23six months training
 Nice piece of reading..
I really like and appreciate your blog article.Really thank you! Really Cool.
 Dear calvin,
I wrote Iphone application for Apnea traing (static tables),
I'lll think it will be great if I can add line from the Iphone App
to your blog , please contact me if you like this idea.

You can get information on the following like

 Thanks Netanel -- I'm sure some readers will find this very useful!
2008-10-01chris holmes
 Is this web site still current? I have been reading it for some time now and find the information a great help in my training. I started freediving 11mths ago and really want to compete in 2009 (static / dynamic) If you could give me a reply on e mail that would be great!!

Thanks for putting all this info out there for people like me to read....I'm on the deeperblue forums.

Look forward to a response..Chris
 Hi Chris -- Since I'm no longer doing competitive freediving, I am not likely to continue updating my journal. I wish I had the time to keep all my hobbies active :) You're more than welcome to post your progress or issues to share with others, of course!
2006-11-17Walter Johnson
 I just came upon this site a few days ago and tried to do a couple of dry static holds. Today I did 3:30 a few hours ago. Later this afternoon I also tried your training table A for the first time all the way through with the default 2:00 hold and starting at 2:00 recovery times just to see if I could do it. I felt ok all the way through it and had no trouble at all. On the last hold I felt really good and decided to hold past the programmed 2 minutes. I went a full 4 minutes on the last hold and fell that I could have gone longer if necessary but I want to travel this road slowly to get accustomed to the feelings at each step. Even after the last extended hold I felt good. The table really helped my confidence if nothing else. I would have never believed that I could hold for 4 minutes. Thanks for all the information on the site. It has been very informative. What are the comparative advantages and disadvantages of both training tables? Unfortunately, I have been unable to find anyone here who is into free diving. I live in Phuket, Thailand. Thanks again.
 Congratulations, Walter!! That's great progress!

These tables work very well, and are perhaps one of the best ways to increase your times from a mental perspective (most people reach their breaking point well before their physiological limits). While it's good to do the tables regularly, don't overdo them (otherwise you'll feel burnt out). The thing that I like about the progression is that you will probably find that each hold gets easier and easier as your body begins to sense that you in dive mode.

As for the tables themselves, the tables with decreasing gaps between each hold are for building up CO2 tolerance. The tables with increasing holds with the same recovery period are for building up hypoxia (O2) training. Most people will release their hold (breaking point) because the build-up of CO2 reaches some limit. The CO2 tables really help extend that limit for you. Keep at it and feel free to post your progress that you eventually reach!
 Its really by chance that I came on this GREAT site. In fact, I was looking for a monofin on the net that I landed here. I am living in Mauritius island and already scubadiving divemaster, however, I find it much more pleasant to practice free diving. If anyone, could help, I would like to know how do I start from scratch to become a good freediver. Thanks.
 Great web site. I'm just getting started with apnea practice and I found your detailed logs very helpful and your progress inspiring. Lacking a local training group (I live in Munich, Germany) for the moment, I've opted for dry static apnea for now for safety reasons. While maybe less exciting than open water free diving, working on relaxation techniques and one's willpower is still quite interesting. In this context, I have a few questions that I have not yet found answers to on your site:

(a) Your times show that your static times are actually longer "dry" than "wet". Nevertheless you (and most others) seem to do an initial 5-minute immersion in cold water to trigger the mammalian diving reflex before competitive breath-holds. Why is this? Does this really add to your time, or is the MDR effect at the surface not significant compared to the "repeat breath hold" effect in reducing your energy consumption?

(b) Are there any known risks or have there been incidents in performing dry static apnea (while lying down) with no-one else present (without lung packing)? Before reading much about training techniques I've worked my way up to 4:19 over two weeks or so by relaxing and performing 4-5 repeated attempts per session with some (so far random-length) relaxation/ventilation inbetween, but now that I've read more about the risks I'm curious if doing this unsupervised really is a safe practice. Any thoughts on this?

Thanks for any advice.
 While some people insist on doing all of their training wet, I think that you can still accomplish a lot of the psychological and relaxation training while on land. Obviously, without a buddy to watch over you, this is the only safe option.

When comparing my dry and wet apnea times, you have to consider that all of my wet training was done in a competition environment in a public swimming pool with distractions, while some of the dry could be done in a more relaxed setting. One certainly doesn't get the benefit of the cold-water immersion kick to the MDR, but repeated increasing holds seems to be pretty effective nonetheless. Most people train with the cold water immersion (mask off, breathing through snorkel) to trigger the body into dive mode faster. It is hard to say quantitatively whether or not it makes a big difference for me, but every preparation counts when it comes time to your final hold. It is also possible that the cold water immersion counteracts the difficulty in finding relaxation in a competition environment.

As for risks in dry apnea, I have asked before and been told by others that it is quite safe. But I wouldn't want to say that it is totally safe as anything is possible. At some point you also get better at recognizing your own body signals so you'll hopefully avoid problems (such as black out) where there could be additional complications.

That being said, I have not read any discussions so far that have indicated dangers of dry static apnea training especially if the trainee is lying down and doesn't use nose clips/mask. But, to be safe, it's probably always best to have someone around if you are going for a max attempt. Read some discussions on the topic.
 I live in a small town. where and how can I learn to hold my breath for 2:00 min. I need to swim underwater for 25 to 50 yards to pass a test for a job. this is required.
thanks for a reply.
 Living in a small town, you might find it difficult to get proper instruction and supervision in trying to increase your breath-holds. So, your best bet is really to book a 1-day class in a larger town if you happen to venture out to one in the near future. That being said, getting to 2:00 should be fairly easy to reach if you're doing it on dry land (i.e. not underwater). At that level, much of the stopping point you'll find is purely psychological. Spending some time with breathing exercises (you can find a number on the net for yoga or pranayama breathing) and focus on slowing your heart rate (relaxing). From there, you will want to work on filling the lungs completely, starting with the diaphragm, chest and upper chest (in order). At that point, you should find yourself easily relaxed and be able to hold for quite a while before the negative thoughts of giving up enter your mind. Focus on relaxation, not stressing out over time or looking at your watch. The discomfort you'll eventually feel is a natural reaction, and you'll typically be able to go long past this initial point of discomfort -- will power. This practice (as it isn't supervised) absolutely must only be done lying down on the floor or on a bed, not in the water! Let me know if you manage to make some progress.
 Me gusto su pagina, soy aficionado a la apnea y mi mayor apnea en seca ha sido de 4:20. y en el agua de 3:20. que tan significativo pueden ser estos tiempos?
 Thanks! Your times are great -- 4:20 is very good! If you are trying to increase your static apnea, the most important part (assuming that you are doing this with proper safety help) is to determine what it is that is stopping you. Are you at your physiological limit (ie. any longer and the effects of hypoxia begin), or are you stopping because of the unpleasant sensations (ie. your mind is stopping you)? Knowing which is limiting you will dictate what you can do to get past this point. Buena suerte!
2005-05-05Dean Valente

Hi Calvin,

I'm glad you posted this training injury. I did not realize there were so many ways to get hurt freediving (lung overexpansions, squeeze etc). I have only heard brief mentions of these kinds of injuries. However, after reading this account and Peter Scotts squeeze story, it made me realize there is a lot I need to understand about proper training.

Dean Valente


With all of the highly competitive training that many of us have followed, limits are certainly being pushed. One has to be aware that investigations into these limits may not have seen as much research as in other sports. The lung squeezes that divers have been facing are definitely worth keeping in mind.

Fortunately, I haven't encountered a lung squeeze yet, partly because I immediately backed off pushing depth when Giovanni got his one (we were both doing 40+m at the time). It seems that lung squeezes may be a very difficult injury to recover from (if at all?), although I have heard that some have recovered OK.

As for my injury (over-packing), it had not been stressed to me enough how dangerous packing was. Everyone does it. While I had heard that some people had injured themselves from it, it was not obvious how close this threshold was to normal every-day training:

  • I was regularly (several times a week) packing to a certain limit, and so it was a shock to see that only adding a couple extra packs (albeit with no warmup) caused injury.
  • I had wrongly assumed that because I was "in-shape", packing regularly, that: a) it wouldn't hurt to skip the warm-up packs and b) that extending my range slightly should be fine.

So, if nothing else, I hope that others would learn from my experience, as it was an extremely frustrating experience. Not only did it rule me out from competing in the Nationals, but it put me out for easily 6 months. You can bet that in this time it is easy to feel that one will never recover! I am obviously extremely happy that I feel 98% recovered, but I look at packing with far more care than I ever did before.

What I think was lacking in the local training community is the education about how dangerous it is and how easy it is for this to happen.


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