hi there,

following is a discussion on this subject. It happened here few months ago.

It's funny to know that the cause is NOT the circulation of blood, & everything you tried is really off course 8-)

read & enjoy,

Erez

Re: loss of feet blood circulation - why ?

Posted By: Paul Lund

Date: Tuesday, 9 May 2000, at 7:43 a.m.

In Response To: loss of feet blood circulation - why ? (Erez)

: does anyody know WHY it happens ?

: Is it because of the interaction between my body & the seat ?

: or is there some other reason ?

Last year I was doing neuroscience research for an Anatomy & Physiology professor and I asked her the same question. She said it wasn't due to lack of blood flow to the feet, but rather a lack of blood flow to the nerves (sciatic nerves) that terminate in the feet. She said it was due to my body weight not being evenly suported over the whole of my butt, instead, it was concentrated on two small areas, one on each cheek. Unfortunaly, the sciatic nerves are beneath these areas, and so, have too much pressure applied to them, and your feet go numb as a result.

: should I blame the seat ? or should I blame something else ?

It is the seat. Perhaps you can adjust the position of the seat slightly, so that it supports the backs of your thighs a little more? I found that this relieved the problem for me, though I'm using a different seat than you.

: how can I tell if the same problem occur with a different seat before I
: install it ?

Not sure that you can, maybe someone else has found a good seat and can recommend one.

Hope this helps.

Paul.

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Re: loss of feet blood circulation - why ?

Posted By: Nick Schade - Guillemot Kayaks

Date: Tuesday, 9 May 2000, at 8:55 a.m.

In Response To: loss of feet blood circulation - why ? (Erez)

In addition to a well contoured seat you need footbraces. The footbraces help support your legs so your thighs don't have to do all the work.

: I use the "therm-a-rest" supplied by pygmy as a seat for my coho.
: It's comfortable, the butt don't ache, but I loose feeling in my feet
: after a while.

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Re: loss of feet blood circulation - why ?

Posted By: Rehd

Date: Tuesday, 9 May 2000, at 10:46 a.m.

In Response To: loss of feet blood circulation - why ? (Erez)

: I use the "therm-a-rest" supplied by pygmy as a seat for my coho.
: It's comfortable, the butt don't ache, but I loose feeling in my feet
: after a while.

: does anyody know WHY it happens ?

: Is it because of the interaction between my body & the seat ?

: or is there some other reason ?

: should I blame the seat ? or should I blame something else ?

: how can I tell if the same problem occur with a different seat before I
: install it ?

: any help appreciated,

: Erez

Rehzzz, try cutting some thin wedges of foam a few inches long and put the thicker end at the front of the seat and tape it down to experiment. Paddle a while and see if it cures the problem. No sense buying a new seat and going through the installation of same, until you know what works for your particular "hiney". Every butt out there is different, so, you have to see what works for you. I don't know the seat, but maybe rounding up the front edge will help with a little inside and outside support. Do a little experimenting with some foam, cardboard, balsa wood or whatever and some duct tape. It'll give you a good reason to get in some paddle time. Hope that helps.

Might give you the incentive to start on that new boat or at least a custom " seat of the pants " seat for the old one. I know how annoying that feeling can be. Good luck with the testing.

Rehd

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Re: loss of feet blood circulation - why ?

Posted By: pete czerpak

Date: Tuesday, 9 May 2000, at 11:50 a.m.

In Response To: Re: loss of feet blood circulation - why ? (Rehd)

Don't forget to perhaps put some minicell or neoprene under where your heels may hit the bottom of the hull. It will make them more comfortable and also aid in the keeping them awake.

Pete czerpak albany, NY

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Re: loss of feet blood circulation - why ?

Posted By: Andy Gere

Date: Tuesday, 9 May 2000, at 3:04 p.m.

In Response To: loss of feet blood circulation - why ? (Erez)

I have suffered from the same problem, despite using a nicely sculpted foam seat (Happy Bottom Pad). Although I haven't completely solved the problem, here are some things that have helped: Try adjusting the seatback and footbrace settings. These changes can dramatically alter the way your butt is supported by the seat. Also, loosening the straps on your Tevas or booties seems to help. Finally, periodically shift in your seat and stretch your legs while paddling. Do this before the sleepy feet set in. I still get this from time to time, but it's not nearly as bad as it used to be.

: I use the "therm-a-rest" supplied by pygmy as a seat for my coho.
: It's comfortable, the butt don't ache, but I loose feeling in my feet
: after a while.

: does anyody know WHY it happens ?

: Is it because of the interaction between my body & the seat ?

: or is there some other reason ?

: should I blame the seat ? or should I blame something else ?

: how can I tell if the same problem occur with a different seat before I
: install it ?

: any help appreciated,

: Erez

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Re: loss of feet blood circulation - why ?

Posted By: Ross Leidy

Date: Tuesday, 9 May 2000, at 3:21 p.m.

In Response To: Re: loss of feet blood circulation - why ? (Andy Gere)

Andy, I bought a Happy Bottom seat once, but ended-up giving it away. You're right that it's sculpted, but it's not deep and it doesn't have any thigh support. Try rolling-up a towel and placing it in front of your seat to see if some additional support under your thighs helps.

Ross

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Re: loss of feet blood circulation - why ?

Posted By: lee

Date: Tuesday, 9 May 2000, at 6:46 p.m.

In Response To: loss of feet blood circulation - why ? (Erez)

Hi Erez, blame anything you like but for goodness sakes take care of the problem at least so that you don't crumple to the ground when you get out of the Kayak. Yes, sciatic nerve pressure, yes follow Rehd's suggestion to experiment with increasing under thigh support. I'm with you on this one because my legs will fall asleep in 20 minutes in most minimal kayak seats. Here's the solution:

1. Make your seat deep and sculpted so that the MUSCLES AND FAT

of your posterior support your sit bones (ischial tuberosities)

UP off the bottom of the kayak. No amount of squishiness

right under that sciatic nerve will make up for the lack of support to all of your weight. When you're a standing homo sapiens your skeleton is doing the job it was designed for. When you're a kayaking homosapiens your gluts,butt bones,etc. weren't designed for extended sitting. So it is necessary to make a supportive seat,especially around the sides,back,and under the thighs.

2. I've tried carving minicell, adding thermarests everywhere,adding thermarests on carved minicell, and making a glass seat formed on a mold of my butt. The thermarests work great but only if they are also on some kind of tractor shaped seat. The glass seat I made for my self has no cushion and is more comfortable than any of them. One combination that works pretty good is a thermarest seat pad inside a creature comfort seat. Carved minicell is the cheapest and best alternative although the grey fluff that comes from all that carving is a mess.

3. Condition your sitting muscles,in other words sitting upright. Stretch often.

4. I've heard a lot of people benefit by having a brace at the heel like Nicks footrests because the calf muscles don't have to be held in tension as much as when one is pressing on the balls of the feet.

5. A wonderful side benefit to all that comfort is reduced knee pressure when rolling or bracing hard since the heaviest thing in the kayak (you) isn't sliding around. I found it was a lot easier to lean my kayak when the support in the seat became better. lee-numbnomore

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Re: loss of feet blood circulation - why ?

Posted By: David Blodgett

Date: Tuesday, 9 May 2000, at 9:24 p.m.

In Response To: Re: loss of feet blood circulation - why ? (lee)

well lets see if I remember today at woprik I was talking to my boss... carl boujahn who has been in kayaks for longer then I'd like to think and I asked him about seats.... he has done some VERY long term sitting in kayaks and this is his solution...

Take a chunk of 3 inch thick mini cell foam... and sit on it... and sit on it... and sit on it... untill your but leaves an imprint... mark with lines like on a map the depest points... more lines for the deeper it is. then carve... nd care and carve... until it is in the shpe it was when you first got off it. then take a 2 inch hole say and cut a hole right where your but bones are right in the middle of each half of the seat. then carve a groove in the middle of the bottom to allow water to pass up and down the keel... then glue it in placce... you may want to leave it loose for a while just so you can get it in the right place... but that should work great.

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Kayak Building Bulletin Board

Re: Velcro it in place

Posted By: Mike Hanks

Date: Tuesday, 9 May 2000, at 10:37 p.m.

In Response To: Re: loss of feet blood circulation - why ? (David Blodgett)

David,

I velcroed mine in place. With enough velcro it will hold it firmly, yet still be repositionable. Use Dap Wellwood contact cement to hold the velcro.

Mike

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Re: loss of feet blood circulation - why ?

Posted By: Mike Hanks

Date: Tuesday, 9 May 2000, at 8:17 p.m.

In Response To: loss of feet blood circulation - why ? (Erez)

Erez,

I had the same problem with my Pygmy Arctic Tern, but I would loose feeling from my thighs down after 20-30 minutes. I removed the Thermarest and put in a piece of 3" thick, 18" long, 16" wide piece of minicell foam in. I sculpted it down to 3/4" thick at the bottom center but left it 3" the front, back, and sides. I sculped it, and sat down, sculpted more, and so on, until I felt no high spots and it was plenty deep. It is as sculpted as any seat I have seen with plenty of thigh support. Before I put it in, I cut the bottom to the shape of the hull. The whole process took about two hours and was ready that same day. Everyone who has tried the seat loves it. It is extremely comfortable and I don't have problems with my feet and legs going to sleep anymore.

Mike

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Re: loss of feet blood circulation - why ?

Posted By: Ian Johnston

Date: Tuesday, 9 May 2000, at 11:08 p.m.

In Response To: loss of feet blood circulation - why ? (Erez)

Hi Erez,

The numb feet problem is not caused by a circulation problem. The major arteries and veins run on the inside and outside of the legs so sitting down doesn't restrict blood flow.

The cause is pressure on nerves. The nerves in your butt specifically. So a seat made to distribute the weight and keep pressure points away from these nerves is the answer.

Ian

P.S.- everytime your feet go numb it is an indication of nerve DAMAGE so get the problem rectified as soon as possible.

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