Leg Drive in an OC1

Sunday, June 01, 2008 / Posted by Rambo / comments (1)

Leg drive is really not what actually happens in an OC1. Yes legs do appear to pump, as in the Paradise video, but that is to allow the hips to rotate to gain further reach. Unlike the Surf Ski/ Kayak stroke which sweeps out to the side and tilts the ski/kayak from side to side, the Oc stroke is straight down the center-line of the hull. The legs are just a part of the connection that starts from heel, continues to circle the body and ends at the blade anchored in the water. The legs pump in response to the twisting of the hips.

Some OC paddlers appear not to pump at all, this i believe is fine as mostly they are larger body types and the torque transfer is primarily through their butt on the seat connection.

Lot’s of top paddlers paddle with their butt very close too their feet, which gives them the high knee look, so obviously there is not a lot of leg drive going on there, just a different style of torque transfer and it works for them. Personally, i cannot paddle this way as I’m too unstable and my learnt style requires that i have hip rotation.

No matter what style you adapt, the most important thing is still getting efficient transfer of power from the paddle to the hull resulting in maximum FORWARD movement.

Chuck in a few bumps, side current and wind and you have a whole new ball game.

A Case Study - Danny Ching on OC1 compared to a Kayaker


In this video of Danny Ching, his leg drive appears to be restricted in an OC1 compared to a kayak. As you can see from this short video of him … there is slight leg movement but no leg drive that i can see, that is not to say that he could be pushing on the heel to lock the knee

Also i have split the screen with a cut a way kayak showing what leg drive is, you can clearly see the difference in foot to butt level, which then allows more rotation.




Cheers Rambo



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Long or Short .. you decide

Monday, July 24, 2006 / Posted by Rambo / comments (1)

A very Detailed Analysis of Long Vs Short paddles ... by Leo Young MD Bsc.

Part 1
From a biomechanical point of view, I believe it's a major, but unfortunately deeply entrenched misconception, to assume that a taller paddler should automatically use a longer and/or bigger outrigger paddle.

Generally speaking, tall and short people have relatively similar torso heights. Overall height differences occur primarily in limb lengths. Accordingly the average height person has a wing span that closely approximates their height, whilst shorter people generally have wing spans less than their height and taller people normally have wing spans longer than their height.

A taller paddler's shoulder height above the canoe seat is usually going to be very similar to that of a short person, but because of their longer arms, their hands will be much lower relative to the waterline. Accordingly, a taller person actually needs a shorter paddle to reach the water effectively.

Furthermore, the effective gearing you are working with when you paddle, at any given blade size, is determined by the distance from the medial center of your scapula (the middle of your shoulder blades) to the tip of your paddle, when your arm is stretched out straight at the catch. The longer this distance, the longer the work lever is and higher/harder the ge you are working with, that is the more work you are doing for any given angular range of motion.

The length of that lever is primarily determined by the size of your wing span and how far up the shaft you grip. So any paddler can increase their working lever, by simply moving their hand up the shaft. But obviously, at any given grip position, taller paddlers are working with a harder gear (longer lever) and doing more work for any given angular range of motion. A taller person using the same size paddle as a shorter person and gripping the paddle in the same position, will feel more load on the end of their paddle.

So a taller paddler can not only get away with using a shorter paddle to get to an effective catch position, but can actually use a shorter paddle to achieve a given amount of work. I believe a lot of taller paddlers unknowingly put themselves at a significant disadvantage by using longer blades that effectively have them way over geared.

I'm 196cm tall, with a 208.5cm wingspan and normally use a 51" paddle, but even feel quite comfortable with a 50" paddle, gripping closer to the blade than shorter paddlers.

Remember, just because using longer paddles for taller paddlers is what everyone normally does, doesn'tt make it correct.

Now before everyone starts enthusiastically challenging these heresies by quoting established kayaking paddle length norms, be aware that whilst exactly the same principles apply, taller paddlers potentially will need longer kayak paddles to give them the appropriate and comfortable spacing they will need between their hands. However, some of this extra grip spacing required by taller paddlers should be achieved by them gripping the shaft slightly closer to the blade, to compensate for the longer lever gear created by their greater wingspan.

Part 2

I need to clarify a point with regards to my earlier post on paddle lengths and gearing. All my previous comments really only considered how heavily the bottom arm is being geared for the primarily important pulling action of the stoke.

For a given paddle length, moving your bottom hand further up the shaft, increases the gearing on both the bottom hand (where creating a longer lever below your hand gears things up), as well as on the top hand (where a shorter lever above your hand increases the gearing effect).

A longer paddle only gears you up more heavily if you move your bottom hand further up the shaft. If you use a longer paddle and keep your bottom hand in the same position, nothing changes directly with regards to the gearing of the pulling action of the stroke, however, you effectively lower the gearing effect for your top hand and consequently the pushing component of the stroke.

Conversely, using a shorter paddle and keeping your bottom hand the same height up the paddle, still gives you the same bottom arm gearing, but automatically increases the gear your top hand is working with.

So Al, before you change paddle lengths, first play around with your hand placement on your existing paddle and differentiate between how heavily geared your bottom and top hands feel. First, find a hand position up the shaft that feels correctly geared for your bottom hand, which is the most critical of the two. At that position, only then decide how appropriately geared and positioned your top hand feels. If things feel to light for your top hand and your hand position is relatively high with reference to your shoulder, you need a shorter paddle. Alternatively, if your top hand is too heavily geared and your top hand is well below shoulder height then you will need a longer paddle. I'd suggest that if in doubt, err towards a shorter rather than a longer paddle.

Of course, the surface area of the blade itself is also critical in determining how heavily geared you are. Once again, I'd suggest using the smallest blade size that you can effectively paddle with, without cavitating through water, even when sprinting. The better your technique, and consequently your catch, the smaller the blade you'll be capable of using and still be effectively catching plenty of water to work against.

If you're producing big puddles that pop out behind the back of your stroke, it means you're missing a lot of water and dragging down a lot of air on the catch. A good catch should be creating either no splash, or a tiny splash in front of the paddle away from you, rather than a back splash towards you.

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