What to do with the Knees? Alternative Sea Kayak Cockpit Designs

Ah, the perpetual debate.  Every sea kayaker will have an opinion and a preference about this, and that preference may change over time.  I was happy with an “ocean” cockpit for many years, moved from looser-fitting boats to tighter fitting ones, then back again.  My thoughts on four general categories of cockpit design below.

1. Knees under in the Middle (Ocean, Greenland)
2. Knees under out to the Side (Standard Keyhole)
3. Open or Exposed (Epic, West Coast)
4. Knees under but High (Keyhole Compromise)

1. Knees under in the Middle (Greenland or Ocean Cockpit)

Pros: boat control in rough water; potential for improved forward paddling form 
Cons: increased effort during entry/exit

Traditional Greenland sea kayaks intended for open water use typically had small, round cockpits to keep the water out and to facilitate the attachment of a seal skin spray skirt or Tuilik.  The first British fiberglass kayaks copied this traditional or “ocean cockpit” design.  It’s a cockpit style that has fallen out of fashion in recent years. The ocean cockpit allows placement of the knees anywhere along the underside of the deck and is often paired with a knee tube or centrally-placed foam block glued under the deck to allow contact points for your knees for boat control.  I used a fairly roomy ocean cockpit on a VCP Pintail kayak exclusively for many years and preferred it over keyhole cockpits for these reasons – more comfort, better forward paddling ergonomics, and excellent boat control with the knees gripping the central foam block.  The downside is the extra struggle to get in and out of an ocean cockpit, which requires shimmying in from the back deck while bracing with the paddle at the shoreline. Not an insignificant annoyance but one that's acceptable to many.

Even smaller ocean cockpits with even lower decks are common on today's Greenland-inspired kayaks, whether skin-on-frame, wood, or fiberglass. These  allow for an even lower knee position which can reduce the up-down movement of the legs and so can limit torso rotation during forward paddling.  But as anyone who paddles a Greenland boat will tell you, their low decks provide superior contact points for boat control.  One school of thought is that the Inuit did not employ much torso rotation during forward paddling, but instead relied on low strokes and “breaking the box” arm movements, meaning bending the elbows more (i.e. the paddle shaft does not remain in-line with the shoulders as much during the forward stroke as compared to the European-style forward stroke). When paired with a Greenland paddle, this less dynamic way of paddling is easier on the body over the long haul and makes sense when one considers that native peoples needed to maintain a life’s time of paddling to survive.

2. Knees under out to the Side (Standard Keyhole)

Pros: boat control in rough water; speed/safety when existing during rough water landings
Cons: may restrict forward paddling form and forces

Sea kayaks began borrowing the keyhole cockpit designs first introduced in whitewater boats, which provide firm and typically low grip areas for the thighs. Edging the kayak and C-to-C rolling with such a setup is fantastic due to the leverage provided by having the knees out to the side “Indian-style”.  Another advantage to the keyhole design is the ability to get the legs out of the boat quickly at the shoreline, providing an added measure of safety during exposed landings.

The problem with the standard keyhole cockpit comes in the forward paddling department. Kayak manufacturers play around with the height of the cockpit coaming’s thigh braces or “thigh hooks”.  Setting them low provides a tight fit and immediate response, while setting them higher allows room to pump the legs a little bit when forward paddling. Either way, with the standard keyhole cockpit’s Indian-style knee position the “line of force” from your hips down the legs to the feet is not a straight line. As compared to surf skis or open cockpit boats (discussed below) which are designed mainly for forward paddling, the angled leg position necessitated by the keyhole cockpit design reduces the effectiveness of torso rotation and the transfer of force from your body to the footpegs/footplate during the forward stroke.  But for most rough-water sea kayakers, the keyhole cockpit is a reasonable trade-off that creates a boat that is just as maneuverable (controllable) as an ocean cockpit-equipped boat with the added benefit that one can easily get in and out of it without a lot of gymnastics.

3. Open or Exposed (Epic, West Coast)

Pros: improved forward paddling, freedom of movement
Cons: boat control in rough water

American-style (i.e. West Coast) kayaks were initially made with bigger cockpits for use in protected waters. Sitting in such a kayak, the knees can be kept together in the center and up above the cockpit rim while paddling but, when necessary, the knees can be tucked under the sides of the cockpit to edge and control the boat.  This cockpit style does not provide substantial thigh hooks so lacks the positive leg-to-deck contact points found in  the keyhole cockpit shape.  But these boats do gain one key advantage - with the wider cockpit opening they can be paddled in a knees-up position similar to surf skis or to K1 racing boats. Some even come with a central foot plate so that the feet can be kept together rather than out to the sides on footpegs.  These elements are of great benefit when forwarding padding. Epic's sea kayaks (inspired by surf skis) fall into this category as do older designs such as the Necky Arluk/Tesla, the Current Designs Solstice, and others – there were many kayaks with open cockpits in the early ‘90’s when I started sea kayaking.  However, boat control in rough water is a little tricky with this cockpit design, relying more on shifting weight and support strokes with the paddle since the knee-to-deck contacts are not immediately available for lateral adjustments (roll trim).

If you don’t paddle frequently in sea state 4 or above the open cockpit design has many advantages.

4. Knees under but High (Keyhole Compromise)

Pros: knees up for improved forward paddling; boat control in rough water
Cons: ?windage?

With the goal of improving upon the keyhole cockpit, designers at Rockpool and Tiderace (and possibly other companies) have added a 3-dimensional quality to the coaming with thigh hooks that dip down into the cockpit opening to allow for a higher, more centered knee position while retaining the keyhole’s other advantages.  I’ve paddled a bunch of kayaks with this design and I can say without reservation that this design is an improvement for most people.  The key features are the more vertical (up/down) surface provided by the thigh hooks, the placement of the thigh hooks closer together to reduce the angle of the paddler's legs, and the greater height at the front of the coaming. This design puts the legs more in-line with the feet (the knees are less splayed out) which allows some additional up-down leg movement and torso rotation. Not as good for forward paddling as a surf ski or open cockpit, but better than the old-style "locked in" keyhole shape. So in a sense, this cockpit design is a "compromise" between the standard keyhole and the more centered-knee position allowed by the ocean cockpit.  Another advantage I’ve noted in these designs is that the thigh hooks are just an extension of the coaming, the kayak’s deck is not part of it.  This allows the cockpit opening to have a continuously round, elliptical shape so that the spray skirt rand fits snug and as a consequence the cockpit can be more water tight than with Standard Keyhole shapes.

As far as “cons” to this cockpit design, if the front deck height is taken to extremes (as in the Rockpool Alaw kayak), this design may add windage and get in the way of low sweep strokes. Also, the front part of the cockpit is a bit narrower with this cockpit type which may hamper a wet exit slightly.  Neither problem a big deal in practice as far as I'm concerned.