Skills And Drills [48]

By David Winkworth

Dead Legs

You’ve just bought a brand new kayak and have taken it for its first paddle off a crowded summer beach. After an hour or so you return to the beach and stylishly ride that big wave right to the sand. Off with the sprayskirt, paddle down, you exit the cockpit and try to stand next to your pride and joy. Your legs refuse to cooperate and they buckle embarrassingly beneath you. You fall over! You’ve just become a victim of Dead Legs Syndrome!

Dead Legs – you hop out of your kayak and they just won’t work! Not cool!

Dead Legs Syndrome was discussed in several groups at the recent Rock ‘n’ Roll weekend so I thought it was worth raising the subject here.

So what is it? Dead Legs Syndrome is a temporary paralysis of your major leg muscles. Whether it is caused by interference with circulation or nerve impulses to the legs I don’t know but it results in a temporary inability to stand up without holding onto someone or something. Maybe someone in the Club with medical knowledge could help here. I sometimes wonder if sea kayakers who spend many hours in their boats are at risk of Deep Vein Thrombosis in their legs. Maybe we should change “Economy Class Syndrome” to “Sea Kayaker’s Syndrome!”

Anyway, it is potentially dangerous, not just because your circulation/nerve impulses are impaired but also because of this: Imagine landing through a vicious shore dump surf onto a steep beach. You have to be up and out of your kayak quickly to stop both you and your boat sliding back down the beach into that surf again. If your legs won’t work, how are you going to do this? You are going to get creamed!

The first general signs of Dead Legs is a creeping numbness and pins-and-needles in the legs and feet. I’ve found that particular seat styles in particular boats can cause Dead Legs for me and I now know what to look for when paddling other’s boats. I usually limit my paddles in these boats to a few minutes.

Dead Legs seems to affect paddlers of all shapes and sizes. There doesn’t seem to be any pattern to it although I suspect that larger heavier paddlers would be well represented in any sample simply because there is more weight bearing on nerves and muscle groups in their bottoms!

What sort of seat styles cause Dead Legs? I’ve found two seat measurements to be critical in avoiding Dead Legs: I modified the seat in a boat I owned and solved the Dead Legs problem instantly.

The first measurement is the fore-aft length of the seat (See Dead Legs Pic 1). I found that if this length was too short, Dead Legs would result. I make my seats with this measurement around 350 mm and I get good support under the backs of my thighs.

The second measurement is the difference in height between the highest and lowest points of the seat. Here’s where we come to the fun part! Stand up, bend over and massage your bum. You’ll feel a bony projection low down on each cheek of your bottom. These are called the ischial tuberosities and they should rest on the lowest portion of your seat. When you are seated, they will be well to the back of the seat.

Now, have a look at the seats in your car and maybe your favourite armchair. Notice how the base of the seat tilts back? Car seats and armchairs are comfortable aren’t they? They have to be because we sometimes spend many hours in them… and it’s the same with sea kayak seats. We may be sitting in our kayaks for 12 or more hours at sea. Any discomfort is going to impinge on your paddling performance and it is only your paddling performance that is going to get you home!

So, I reckon sea kayak seats need some fore-aft tilt to be comfortable. Not so much that it will restrict us transferring our weight forward and back to get the best performance out of our boats but enough for long day comfort AND for support under our thighs. I think it is the support under the thighs that is the second critical measurement in stopping Dead Legs. Remember that when we are properly seated in our kayaks, our thighs are braced up under the coaming and foredeck. That is, there is an upward rake in our legs from our bottoms to our knees. The backs of our thighs need support. I make the difference in height between the two points shown in Dead Legs Pic 2 around 40 mm. In boats with a relatively high coaming height, this could possibly be 50 mm.

Dead Legas Pic 1 - the fore-aft length of your seat is important

Dead Legs Pic 1 – the fore-aft length of your seat is important

If you suffer from Dead Legs in your kayak, you may want to modify the seat. By far the easiest way is to use closed cell foam. It is warm, easily worked with cutter and sandpaper… and if you make a mistake you can rip it out and start again. A word of caution: If you use contact adhesive to modify your seat, you may find it coming unstuck when wet. A stronger but messier adhesive is Sikaflex. You can get it at marine stores.

Dead Legs Pic 2 – a substantial difference in the height between the indicated points is important

While we’re on the subject of seat modification, at the Rock ‘n’ Roll weekend each year we always seem to instruct some paddlers who are just not firmly fitted into their kayaks. A firm fit in the seat is vital to the performance of your kayak. It must be able to respond to inputs from you! Let’s look at where you need to be in contact with your boat: The seat: a good snug fitting non slip seat is essential. Firm hip support a fair way up is also needed (See Dead Legs Pic 1). A backrest of some design is needed too so that you can push hard against the footrests and really lock in when you need to. The backrest should not be so high that it will restrict you leaning back when you need to.

Rolling requires a firm lateral fit in your seat. When you come around the boat should too!

Footrests should be solid. They are going to carry nearly all of the force you exert on the boat. If yours are the slide-to-steer variety, you might consider talking to senior Club paddlers about solid options.

Lastly, the thigh braces. These are important for hip flicks in rolls and for edging and steering the kayak. Thigh braces should be just that: a brace for your thigh muscles just above and inside your kneecaps. These are big strong muscles. Some paddlers at the Rock ‘n’ Roll weekend had their kneecaps in contact with the underside of the deck. Kneecaps are bone covered in skin only and are not suited for constant hard pressure. If your kneecaps are touching the deck, consider making up some foam pads to let your kneecaps float free. After a long day in a good sea they will love you for it!

Australia’s Greatest River – The Murray River Paddle

In mid March 2002, some of us are paddling along the Murray River from Echuca to Swan Hill over a week. Start date is Sunday 17 March. This is a Grade 2 paddle (see Club Trips Calendar). There will be no surf breakouts, whirlpools, tide rips etc. but you will have to do about 50-60 km per day. Total distance is 312 km. For those members with moderate fitness this will not be difficult as there will be some current assistance and your fitness will increase each day. This paddle is also good opportunity to wash your kayak!! It ain’t the ocean but it is different and the Australian inland river scenery is all around you!

This is a paddle-at-your-own-pace paddle. During the trip we will detail the next camping area on the maps each morning and you can take all day to get there if you like. In 2000 we did a higher section of the Murray like this and paddlers formed small groups and it all worked well. We will have a tail-end charlie paddler to deal with any problems you may have along the way. There are plenty of camping spots so we won’t all be crowded into the one area (or state!). We will pass through Torrumbarry Lock and a couple of small towns where you can re-supply as needed. Camping will be on the redgum forest banks of the river.

If interested, phone me for an information sheet on (02) 6494 1366 or email me at storm@acr.net.au

Navigation Skills Weekend

I originally had this weekend scheduled for Twofold Bay in late winter in 2001 but postponed it because of too few numbers to cover costs. It mysteriously reappeared in the Trips Calendar for late December but that was not my doing! I plan to reschedule the weekend for about May 2002 at Jervis Bay or Batemans Bay. A lot of people have expressed interest so it will be ON. Keep an eye on the Calendar.

Stowing Your Stuff

Another subject that came up in discussions at the Rock ‘n’ Roll weekend was carrying camping gear in your sea kayak. For those members new to sea paddling, there are a couple of principles that you would do well to keep in mind when packing for your next multi-day trip: KEEP IT CENTRAL

This just means that when packing your boat, the heavier denser items should be placed as close to you in the cockpit as possible. Items such as full water containers, stove and tent should be packed against the forward and aft bulkheads. If possible some heavier items such as water containers that don’t need waterproofing may fit in the cockpit. The important point with packing items in the cockpit is that they must be secure. Never underestimate the power of the surf to clean out your cockpit! Lighter items can be pushed up the ends of the boat UNTIL the heavier items are stowed. These lighter items should then be pulled back down the hatch to pack the heavier items in tightly.

Why are we trying to keep the ends light? Simply to make it easier for us to control the kayak. Lighter ends mean easier turns and less plunging and pearling in waves.

Keep it Light

We are lucky in sea kayaking – we can take that extra bottle of wine that bushwalkers would leave behind, and not notice the extra weight too much. It’s great to be able to take along a few luxuries and we all do it. It’s great. The extra weight can become a problem however when we overdo it with gear and we’re caught in tricky sea conditions.

Extra weight can dampen the response of your kayak to waves. This can be good if it settles a “tender” boat down in marginal conditions. It can however make your boat slower to respond when you need a reflexive brace and also make your kayak harder to turn.

Where we lose out with extra weight is, I think, in acceleration. In following sea situations, extra weight may mean not being able to get that last bit of speed to catch the waves. Similarly, in a head sea, each wave that your boat breaks through is slowing you down. You then have to accelerate your kayak back to your cruising speed until the next wave hits you… and so on. Acceleration is intimately linked to mass. Heavier boats are slower to accelerate and require more energy to do so.

So, next time you pack for a trip, consider the seas and conditions you are likely to encounter. Never ever leave any of your safety gear behind but do get out the kitchen scales and check the weight of a few of your items. You may be surprised!

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