How much harder is it to freedive in cold water?

[laminar]

Sean,

It doesn't make sense to be that you would need more weight for FRC than you would for inhale diving because of the great amount of buoyancy that a few extra litres of air represents. But I trust that you've tried everything out. One question, are you neutral, negative or slightly buoyant at the surface? While it is wonderful to sink from the surface, you also need to factor in the energy cost of staying off the bottom once you get down there and the cost of staying on the surface if you sink beneath it during a breathe up.

I find that when I wear a 6.5/5mm combo it's a little more tricky to get the right weighting for dives of variable depth. These days I spend most of my time in the 10-20m range for video and photography) with the occasional fun dive to 30m+. So I try to find a weighting that allows for the odd deeper dive. I really hate to be negative on the surface because it's hard to relax. The compromise I usually make with my weight belt is to need to breathe higher than FRC during my breathe up, so that means never exhaling fully, or if I do, it needs to be done quickly, because I'll start to sink slightly, enough to make an inhalation somewhat more difficult. This isn't perfect, but it seems to be the best weighting for when I'm starting the dive and when I'm down underwater. It all depends on the underwater topology as well. If you are slightly more weighted and you are crawling down a steep wall, keeping yourself away from it with a finger on a rock now and then, it's going to be fine. However, if you're trying to stay off a flat bottom, it's going to be a pain and you'd want to dive with a little less weight.

This weighting also means that when you reach the surface at the end of a dive and take a deep breath, I'll be buoyant. If you want a higher margin of safety, then it would be best to be slightly buoyant on the surface, even with no air in your lungs. Lots of tradeoffs. Waste energy during the dive and have a problem at the surface or conserve energy during the dive and dive more conservatively so that you can manage yourself on the surface.

Diving with no suit is a dream with FRC. A 3mm is no bad, but I find myself buoyant in weird places (like the head), which makes things a little awkward.

Amihov,

7 mm seems like too much for Vancouver and 10 kg is a lot of weight. You may need to learn to embrace the cold a little more and enjoy being able to swim more easily. But everyone has their own preferences, of course.

I'm diving without fins these days. The weight of a monofin does make a difference and of course gives you more range given a certain weighting. I'd say the range is much less with bi fins.

Pete

[Fondueset]

I use a 6 mil smoothskin out for winters around here - thats with 3c water. Though I've done a winter in a 5 mil with no problem - just somewhat shorter dives. I have to say the smoothskin makes a HUGE difference in warmth. Heat loss during breathups in cold weather is a major factor and the smoothskin suits wick much less heat away.
30meters with no fins!
What about fish stalking? With some species here I have to minimize movement in order to get close that includes the trip down.

With the 6 mil compressibility is such a factor that I can be neutral at 7 or 8 meters, float like a cork at the surface and still be sluggin along at 20 meters. 3 mil seems like about the nicest suit thickness.

[harbour seal]

pete,

it is great to hear from someone with so much diving experience, particularly with the frc style in cold waters using a wetsuit. i very much appreciate your input.

buoyancy issues have been bit a bit confusing to wrap my head around, thus i really don't know whether the weight i am using for frc makes sense or not. let me explain the process i went through and perhaps it will help clear the waters, so to speak.

most of the summer i dove with only a 2mm vest/hood/2mm shorts using 4lbs on my waist and 2lbs on my neck. using this amount, i was positive on the surface during breathup (more weight made me negative), although higher waves were somewhat problematic. after exhaling, i would do 3-4 kicks and then sink. i spent most of the summer diving in this fashion for 90 min sessions in the 8-15m range; however, i would be fairly hypothermic by the end of a session, requiring 3-4 hours to warm up.

at the end of august, i started using my 6mm/5mm nylon-out, new black coating in, elios suit. initially, i found i was way too hot and had to cool off by frequently flushing or diving with the hood down. it seemed to help markedly if i swam for awhile to cool down before suiting up. using the suit allowed me to stay in the water for much longer (approx 3 hours) and not be cold when i came out, which can be laborious after awhile.

regarding the weight, i built a 16lb custom weight harness (see http://forums.deeperblue.net/freediv...tml#post664882), which is equivalent to the weight i previously used on my belt for inhale. using 16lbs on inhale i am neutral at approx 8-12m, an estimate made during my first few freediving sessions the previous winter.

wearing the harness for frc (with my wetsuit), i found i was too buoyant (after passive exhale) and didn't really start sinking until approx 5m. i tried experimenting with different amounts of weight and eventually found that adding 4lbs on a waist belt and 2lbs of ankle weights seemed about right (total 22lb). using this amount, i am positive on the surface during breathup and after exhaling i do two or three kicks and start sinking. using more weight i found i was negative after exhaling during breathup, which is a pain in the butt and led to many flooded snorkels, not to mention it was nearly impossible to relax face-down in waves.

another benefit of this setup is the weight harness (the majority of my ballast) shifts my centre of gravity farther down towards my head, thus making head-down sinking easier. additionally, the ankle weights have the added benefit of helping to keep my legs down when i lay on the bottom.

regarding the added energy required to stay off the bottom you mentioned, i hadn't yet considered this as an issue. i expect it is because my dive times are quite short thus i don't have too much time for exploration along the bottom (usually in the 40-60 sec range using frc---more on inhale). i generally use an aspetto approach even though most of my sessions have been strictly freediving (not hunting). lying motionless on the bottom (or holding onto a wall), i can watch the shrimp dance in the sand and the resident fish will come over and check me out. also i often enjoy slowly crawling along the bottom pushing myself along using my hands. using a smooth skin open-cell wetsuit i would expect you need be careful to stay off the bottom, especially compared to my approach using a nylon covered suit.

the only other factor i can think of regarding my buoyancy and associated weighting between exhale and inhale is the size of my lungs. i think i may have smaller lungs than most, thus the difference between a full inhalation and a passive exhale might not be as much for me as with others.??? although this ratio may be constant regardless of lung size???

over the winter i am planning to order a 3mm elios suit for use during the summers, as my current wetsuit was too hot. from all reports this should be much nicer for diving than my current suit, which i already find pretty darned sweet (if i don't get too hot). i can't wait!

finally, you are diving without fins? how do you find swimming with neoprene socks? a while back, i read that tyler z was doing this after his fins were stolen. perhaps you guys are starting the next trend to sweep through colder water diving (frc being the last).

cheers,
sean
vancouver, canada

ps. i welcome insight/comments/opinions from everyone

[Fondueset]

I was just out in my 5 mil. I have 10lbs on my belt at 2 in my vest (just enough to help keep the upper body down. Its shallow quite far out in my fav spot right now so I am mostly swimming along the bottom out along some old pipes - I'll swim out about 500 meters or so, then over to the breakwall to visit with the fish. Max depth is only about 10 -12 meters and I'm allready too negative starting at about 9 (neutral at 5 or 6)- I am not diving frc! Now, I may have less body fat, or smaller lungs or whatever, but it seems to me you might be a bit overweighted for frc. For my 6 mil I might add 2 - 4 lbs - for a max of 16lbs - but probably only 2 as I tend to dive in a deeper area - still only 15-20 meters - when the water gets really cold and clears up.

How is your entry? It may be you don't even need those first few kicks!

Everybody's different - but I like to be able to glide along the bottom and enjoy the ride up

[harbour seal]

Originally Posted by Fondueset

...Now, I may have less body fat, or smaller lungs or whatever, but it seems to me you might be a bit overweighted for frc. For my 6 mil I might add 2 - 4 lbs - for a max of 16lbs - but probably only 2 as I tend to dive in a deeper area - still only 15-20 meters - when the water gets really cold and clears up.

How is your entry? It may be you don't even need those first few kicks!

Everybody's different - but I like to be able to glide along the bottom and enjoy the ride up

fondueset,

i always pay close attention to advice from wise forum members such as you and peter. i am but a mere novice diver out exploring my love affair with the water, and open to any means of deepening my immersion.

i have only been freediving for less than a year thus i know i have much to learn. things like my entry and bottom time need improvement, although i do conciously try to minimize any unecessary thrashing. unless i were to do something as silly as losing my mask, then i thrash profusely . from what i read here, it is more than likely i will need to lighten my set-up as i improve, especially if diving deeper than my present range of 8-20m. my current weight configruation does afford me the ability to sink without much effort, which is a most sublime feeling.

in the near future, i hope my frc bottom time improves so i can spend more time gliding along the bottom as you describe.

cheers and thanks,
sean

[Fondueset]

I've only been back in this game with intensity for 3 years or so - and I can only mumble inarticulately and twitch in awe of the likes of Pete and Eric - you actually live near them!
I also am not yet an FRC mutant - though it seems to happen with many of my shallower dives. You and I are diving about the same depths - but I cheat by bringing more air with me.
I hope to get out there again sometime soon - I believe BC is my favorite place on the planet.

PS - I lost my fav snorkel the other day - I can only qualify my humiliation by saying I lost it either on the way in or out. (possibly I should dive No-Snorkel for a few months?) Of course I have two more - but they are not impulse IIs - with which I have a spiritual affinity. If some cursed retch found and made off with this sacred power object I can only wish it brings them everything they need..

[harbour seal]

i remembered i was asking about weight for frc diving earlier in the summer:

http://forums.deeperblue.net/freediv...ch-weight.html

sorry about your snorkel, i feel for your loss fondueset. british columbia is by far my favourite place in the world as well (too many beautiful spots to mention).

sean

[efattah]

My experience with FRC, with a thick suit down to no suit, is that I need the same amount of weight with or without the suit, for FRC or for extreme packing dives.

Diving FRC with a 6.5/5mm config, I need to kick 2-3 times to start sinking. Without the suit, with a small neckweight, I don't need to do any kicks to start sinking. In the same configs, with full packing, I need to kick hard down to 30m to start sinking.

Attempts to add more weight while using the suit, in an attempt to sink from the surface, always resulted in worse dives.

[Atlantis Fire]

I have no professional training whatsoever, unless you count lifeguarding and scuba. But I have found the biggest difference temperature makes, is with how easy it is to relax. Up here in the north Pacific, it's considered warm at 12 C. Usually even wearing a full 7 mm suit and hood, you start shivering within minutes. Having my teeth clacking together really makes slow deep breathing and relaxation difficult. PB with fins for here is about 12 m, PB in Florida was more like 18 m. I'm not quite sure exactly how deep my max was.