How much harder is it to freedive in cold water?

[Stavros]

Originally Posted by m2b

Since I've never taken a freediving course I can't speak from experience but I can ask this question:

Who says the instructor has to be the safety diver as well? Quite frankly a setup like that should not be allowed. The instructor is there to teach not to act as a safety diver. The "job" titles should be completely separated with no carry over permitted.

Originally Posted by m2b

The instructor should ALWAYS be on the surface/out of the water.

Just my opinion,
Ryan

1. The instructor is the organiser and person responsible for any course and he must be able to ensure the safety of the students if something goes wrong. The instructor can choose to have extra safety divers but I 've rarely or never heard of that happening (maybe more than one instructor in a class but never specifically designated safety divers)

2. How is the instructor supposed to observe the technic of the student if they stay on the surface?
(Think of a 25m dive with 5m visibility in the UK)

3. Who demonstrates during the course if the instructor stays on the surface / cannot dive.

You would be happy with a course were your instructor stayed at the surface?
My students would definately not be - one of the things that students really benefit from is seeing an experienced freediver move in the water...

Cheers Stavros

[samdive]

Ryan - it's not about whether he is allowed to join us, if you read the post you'll see it's about how much less depth he/she can expect to achieve in colder water, thicker suit.

Research on learning - done a fair bit of that as a scuba and freedive instructor trainer and having worked for several years as a Training Consultant for PADI but thanks for the advice anyway....

We have a saying in PADI - RTFQ!

It stands for READ THE F*** QUESTION!

[samdive]

Good points Stavros - of course the instructor should be in the water - how else can you teach? We usually have two instructors in the water and dive with every student - or at least whenever they go out of sight (in 5m vis).

Sounds like about a 5-10m drop might be normal - which is what I thought so I'll stick with that advice in future. I'd never put the plate at someone's Dahab PB the first time they came to the lake, just not safe- but I'd consider 5m less as a start point.

Thanks for the constructive info

S

[apneaboy]

If we are taking the scenario of a diver coming from Dahab for their first UK dive and taking off 5-10 metres off their pb are we then recommending a diver who dives in colder fresh water go to Dahab for their first sea dive, with a bit of chop, different density water so having weighting issues and put on 5-10 metres on their pb then??

That wouldn't be prudent either.

I think an instructor going for the performance requirements to get their instructor ticket can wear a thinner suit for a single dive and then train students in a thicker one if they are going to be in the water for a couple/few hours if they thought they would have a problem.

[Stavros]

Originally Posted by samdive

Good points Stavros - of course the instructor should be in the water - how else can you teach? We usually have two instructors in the water and dive with every student - or at least whenever they go out of sight (in 5m vis).

Sounds like about a 5-10m drop might be normal - which is what I thought so I'll stick with that advice in future. I'd never put the plate at someone's Dahab PB the first time they came to the lake, just not safe- but I'd consider 5m less as a start point.

Thanks for the constructive info

S

All this talk about diving in the UK is making me sooo curious...its a shame I have no trips planned to the UK in the foreseeable future...

Maybe next year.

Cheers Stavros

PS. I would have to say that if I went for a max dive (my current pb is in the high 70s in warm water) in a cold dark lake I would reduce my max depth (I'd probably do a first dive to 60 and then the next session I 'd try 70 depending on the feeling) but I think that’s because I know that the high 70s in good conditions with divetimes of 2:20-2:40 is getting me quite close to my apnea limits. For a person with limited experience who is mainly being stopped by equalisation or fear of depth etc I would not say that the reduction would have to be so big. (on the other hand if I just wanted to have fun I would say to set the line at 80 and go by the feeling which is why I suggested the 0 reduction in depth )

[harbour seal]

interesting dicussion everyone.

Originally Posted by efattah

Also note that the penalties for various wetsuits differ, based on if the diver is packing, or not packing, or FRC diving. An FRC diver generally suffers less of a penalty for a thick wetsuit, especially for middle depth dives.

eric,

could you explain the bit about frc divers having less of a penalty? is this due to less overall lung compression and thus less buoyancy change?

in general, i am still a little confused about buoyancy change and its effect on a dive. does less buoyancy change means less effort overall? but doesn't buoyancy change essentially cancel itself out in that you sink easier as lungs/suit compress (descent) and ascend easier/faster as they re-expands.

cheers,
sean
vancouver, canada

[BennyB]

Come on Stavros, get your finger out and come on over! I'll buy the first pint

[samdive]

Yup Stavros - and you can tell me your PB before you come out and see what you can do in the lake

come to think of it - any more warm water divers out there want to make this into a real experiment rather than a web discussion???

saltfree meet tomorrow - and again 27/28 October...

S

[m2b]

A little off topic but still on topic at the same time.

In the beginning of the thread some of the possible things mentioned as causing problems/needing to be "weighed" was water temp, bad vis, and current. When you guys speak of current causing trouble what are you referring to? What is the source/s of the current and how does it effect you, including at what kind of depth? I had a rather unique experience today that I'm questioning if it was current problem or what the heck was going on. It really caught me off guard, on two completely separate bodies of water.

Ryan

[Fondueset]

Harbour Seal,

I think you're basically right about what Eric said. For example - with a 3 mil suit vs 5 mil there is dramatically less change due to suit compression - because the suit has less air volume. Same with lungs. consequently less effort going down and coming up - also less effort swimming along the bottom. FRC divers can also dive with less weight.

[amihov]

I want to add something about cold and warm water. I know i am not a big expert but i have been diving for about 2 years now. In Vancouver i am diving whit a 7 mm suite and i have about 10 kg lead on my belt. Going down is hard and going up is worse i live the sea live in Canada it is one of the best places but i have to say it is so much easier if the water is warm. This summer i was diving back in Bulgaria water temperature was around 26 c all the time. I was spending more then 1 hour in the water on wet suite no weight belt. Going down to 15 meters for me was just like a child play . Swimming up the surface only took about 2 kicks it was soooo much easier . I was doing thining that i have never done before in vancouver i was going down 15 meters and spending time taking pictures swimming around for atleast 25- 30 m on a 15 meters dept searching for fish. And when the time to breath comes up all i did is just kick 2 times and i was on the surface . Warm water no suite is the best diving and the difference is huge comparing whit a cold water diving. Again cold water is fun to but the it is much harder because of the suite and the weights.

[harbour seal]

fondueset,

of course, less air volume in the suit, thanks for the reply. for some reason buoyancy change is hard for me to wrap my noodle around. using my 6mm/5mm elios wetsuit, i dive frc with more weight than inhale; it is the only way to be able to sink from the surface after one or two kicks. it would be great to dive frc in warmer waters using less weight.



amihov,

thanks for the excellent trip report comparing vangroover and those sweet sounding tropical waters of bulgaria. i would love to dive in 26 degree water. no wetsuit and no weights sounds like heaven. i still love our emerald green waters, even as frigid as they may be.

cheers,
sean
vancouver, canada

[amihov]

I really like diving in Vancouver . I have seen many interesting things in our local waters. One thing i need to say is i have the feeling that you are using to much weight. Be careful you should be able to start sinking around 7 to 8 meters when you have a wetsuite. If you are sinking from the first 3 meters you may have some problems if you go under 12 meters. Check the weight . I had some bad experience in Vancouver where i was using way to much weight . You may have some hard time getting back to the surface .

[harbour seal]

Originally Posted by amihov

I really like diving in Vancouver . I have seen many interesting things in our local waters. One thing i need to say is i have the feeling that you are using to much weight. Be careful you should be able to start sinking around 7 to 8 meters when you have a wetsuite. If you are sinking from the first 3 meters you may have some problems if you go under 12 meters. Check the weight . I had some bad experience in Vancouver where i was using way to much weight . You may have some hard time getting back to the surface .

amihov,

i appreciate your consideration regarding the weight and potential problems.

regarding my extra weight, i am diving the frc (functional reserve capacity) style where you passively exhale before descending (also known as exhale diving). to use this technique effectively you need to sink from the surface (or thereabouts) and passively descend; the entire descent should essentially be a static. in order to be able to sink like this, while wearing a wetsuit, you thus need to be weighted heavier than when diving on full inhale.

i am far from being an expert, as i only switched over completely to exale at the outset of the summer. i am diving frc in the 10-20m range, which is as deep as i have been on inhale as well. as far as the amount of weight, this required a little trial and error with different amounts before i found what felt right. as of yet, i haven't experienced any problems with the added amount of weight. others feel free to chime in here if i am off base.

sorry to sidetrack this thread from the cold water discussions. if anyone is interested, there are a bunch of excellent threads here on db detailing this style of diving. search for "exhale" or "frc" and especially look for posts by sebastian murat and (of course) eric fattah.

cheers,
sean

[Fondueset]

That's interesting Harbour Seal. I know about the weighting in FRC But since I dive alone alot I like to be positive at the surface. Makes for easy breath-ups and easy ascents. Now that I'm back in my 5 mil the compression diff is really noticeable. When I'm swimming with my monofin I have to swim much faster to stay off the bottom at 10-15 meters. I'm thinking about going with even less weight! I'm not doing FRC except in 3-5 meter depths as a way of adjusting buoyancy but I wonder about the energy trade off - easy descent vs easy ascent and easier bottom swimming.