Sunday, June 29, 2008

Shoulder Safety

Imagine a basketball balanced on a golf tee. The basketball is the end of your humerus bone. The indented part of the tee the basketball is balancing on is your shoulder joint. It’s not very deep, and it’s not very big, considering the large ball that’s resting on it. And therein lies the problem. The shoulder socket is very small, while the humerus bone resting on that socket isn’t. The shoulder socket is designed for range of motion, and not designed to be a weight bearing joint (like how paddlers use it for bracing, turning, or rolling). In contrast, the hip socket is a weight bearing joint – the bone is set deep in the socket for stability and to prevent a large range of motion. (This explains why dislocating a hip is horribly painful)

The ratio of a basketball to a golf tee is actually pretty accurate when describing the shoulder joint. Now imagine how easy it is to knock that basketball off the tee and you can see why shoulder dislocations are fairly common. If not for the skin, muscles, tendons, and ligaments that surround the shoulder, humans would perpetually walk around in slings. As it stands though, it’s only kayakers that perpetually walk around in slings. Usually, the paddle is the culprit when a kayaker dislocates his shoulder. Archimedes once said, “Give me a lever long enough and a fulcrum to place it on and I’ll move the world”. Your paddle is that lever, and although it’s only 197 centimeters long, it’s plenty long enough to apply the minimum pressure required to knock that basketball off the tee. Keeping your shoulder in a strong position while paddling is therefore of utmost importance. A strong position is one in which the elbows stay below the hands and the hands stay in front of the torso. The easiest way to achieve this strong position is by rotating your torso with all your strokes – especially strokes done at the back of the boat.

Below are two pictures of a sweep stroke. In the first, the paddler has rotated his upper body with the stroke. His elbows are bent and below his hands, while his hands are in front of his torso. This is a strong position. In the second picture a paddler has not rotated his torso when doing the sweep stroke. You can see that the elbow is above the hand, and the hand is not in front of the torso. This is a weak position.

Strong and weak shoulder positions can also be applied to rolling. In the first picture below the paddler is executing a sweep roll. Notice how he has twisted his torso as he rolls to ensure that his hands stay in front of his body as his rights himself. (One of the easiest ways to achieve this is by following the lead paddle blade with your eyes). His left hand and elbow stay tucked close to the body to maintain a strong position. In the second picture the paddler is not rotating with the sweep. This puts a lot of pressure on the shoulder and is a weak position. The shoulder has become a weight-bearing joint – something it was never intended to be.

This concept also works with bracing. It is often said that a low brace is safer than a high brace. In actuality, a poor low brace and a poor high brace can dislocate your shoulder equally well. Both braces should be executed with the bracing blade planted in the water in front of the paddler. Bracing perpendicular to the paddler, or behind the paddler (even worse) places the shoulder at risk. The farther back you brace the more you load the blade with weight, and the more you’re depending on the shoulder alone, and not the other muscle groups, like abs, obliques, and pecs to stay upright. A high brace is perfectly acceptable so long as the hands aren’t rising above the head.

A low brace is acceptable as long as the elbows aren’t rising above the hands or head. Below are four pictures. The first and third pictures demonstrate a shoulder-safe high and low brace, respectively. The second and fourth pictures demonstrate an unsafe high and low brace, respectively.

Thursday, June 19, 2008

Turn less, not more

In our advanced level instruction we spend a lot of time “re-teaching” people to paddle. Most of these guests are great paddlers who learned to kayak in Dancers, RPMs, etc and have now transitioned to the planning hull boats or shorter playboats. This transition is not always smooth for the simple reason that these smaller boats do not paddle the same way as the longer ones.

The longer boats are more difficult to turn and thus a paddler may need a combination of strokes to turn the boat. For example, to catch an eddy in a longer boat the paddler might utilize a forward sweep into a stern draw into a bow draw. Using that stroke combination in the smaller boats is unnecessary – it will in all likelihood spin you in a 720 degree circle down the eddy line. If this doesn’t make sense think of it this way – in the longer boats you focus your energy on turning the boat aggressively whereas in the smaller boats you focus your energy on preventing the boat from turning too aggressively.

In the 1990’s, we taught peel-outs with the “speed-angle-lean” concept. You have probably heard this at some point in your paddling career. Accelerate towards the top of the eddy, set a thirty degree angle, and then lean downstream as your boat peels out. This worked well because the longer boats carried the speed you built up in the eddy across the eddy line and into the current. This does not work as well in the shorter planning hull boats because they’re not very fast. If you try and use “speed, angle, lean” in a short boat you’ll find that often you don’t have the speed to bust through the eddy line into the current and you simply spin on the eddy line which is not very stable.

Instead of focusing on speed, focus on preventing the boat from turning too soon. As you hit the eddy line, that planning hull boat wants to spin. Don’t let it. Use a forward stroke on the downstream side to accelerate the boat onto the eddy line, and then link it to a slow stern draw on the same side, to prevent the boat from turning downstream. (Or if the current is slow, just a stern draw) You’re not so-much peeling out of the eddy as ferrying across the eddy line with a two-stroke combo. You are now in control of the boat – you can continue the ferry, do a peel out, or return to the eddy you came from. With “speed, angle, lean” you’re not really in control of the boat – the water is. It dictates when and how quickly you turn.

The same applies for catching an eddy. Of course you will need a little speed to cross the eddy line, but you will also need a stroke or two (now on the upstream side) to keep the boat from spinning too quickly and preventing you from driving deep into the eddy. As you cross the eddy line plant a forward stroke in the eddy water to pull you across the eddy line, and then use a stern draw on the same side to keep the bow of the boat from turning upstream too quickly.





For precision boat control in the newer boats you need to use stroke combinations to limit the boat’s turning ability, not stroke combinations to turn it more.

Friday, June 6, 2008

Go Green!

This year, for some odd reason, the instructors have spent an incredible amount of time paddling upstream. Three to five times a week we hop in a river-runner, put in at the Outfitter’s store and attain up to Nantahala Falls. It’s a heck of a workout – at least until the Green Boat arrived two days ago. Now it’s not so hard, and has become significantly more fun.

Let’s get the obvious out of the way first – it’s fast, real fast. It accelerates quickly and as you accelerate the bow of the boat rises slightly to maintain speed. The other nice thing about the Green Boat is it doesn’t slough its speed off like a typical river-runner. It starts fast and it stays fast. We also noticed that a well-timed stroke will lift the bow onto waves or holes before you get to them which further prevents the boat from losing speed.

The Green Boat derives part of its speed from its narrow width, so it feels more tippy than your typical creekboat. The advanced paddler (like the one racing the Green) won’t have any problems with the secondary stability, but there may be a bit of a learning curve for us mere mortals.

Additionally, this boat isn’t going to turn like other river-runners/creekers, but it wasn’t designed to turn. This boat was designed to lock in the line the paddler sets, and then drive through that line. This boat won’t be pushed around very easily.

Lastly, this boat is really fun to boof. I’d be giggling before I even got to the boof rock in anticipation of the air I was about to get. Even if you don’t ever plan on racing, do yourself a favor and demo this boat if you get a chance. It’s really fun – which is the reason we kayak in the first place.