Saturday 17 January 2015

More Thoughts on SUP Technique

If you’ve read any of my previous blog posts on technique or been to one of my clinics you’ll know that I have some fairly strong ideas on technique.  I’ve always felt that there are certain, fundamental technique principles that apply to all types of paddling that you need to take into account if you are going to paddle well.  Beyond that I’ve always believed that there are many ways to interpret these principles and incorporate them into your own technique.  We don’t all have to look identical when we paddle.  The trick for each of us is to find out how to incorporate the basic principles of paddling into our technique in the way that works best for each of us.

Since I started working with the Canadian Canoe/Kayak Team last June I’ve had access to some pretty cool technology that allows coaches and sport scientists to better understand a paddler’s technique and provide paddlers with feedback far beyond that which you can provide by simply videoing them.  Some of this technology is pretty developed and ready to use daily. Some of the technology is still developmental, but we hope to have it ready to use daily with the team this coming season.  As you can imagine I’ve been eager to use this technology to look at the SUP stroke as well.  What it has shown me so far has been both interesting and useful.

The cool thing is that this technology, while reaffirming the basic principles of paddling, has also shown that some things related to technique that people might consider really important are in fact not really that important at all.  Other things related to technique, while actually correct, can easily be misinterpreted in their application and hurt your technique.  Finally, using this technology has confirmed what I have contended all along – that there are many interpretations of basic paddling principles that can be used to move a SUP board effectively.  It isn’t really a matter of one technique being better than another.  It is instead of question of each individual finding not only the right technique for them, but also finding the right “gear” to paddle in (see my blog post “Stroke Rate in SUP Paddling”).

Without any further introduction let’s get down to looking at things in detail:

Pulling the paddle through too far (past your feet)

There are a couple of SUP forums on the Internet and if you ever check them out you’ll inevitably find a thread discussing whether or not it is okay to pull your paddle past your feet.  And there is usually a “senior member” of the forum, with thousands of posts, who will tell you in no uncertain terms that pulling the blade past your feet is bad.  He’ll insist that pulling with a negative blade angle causes the back of the board to be pulled down, ruining the boards trim and depriving it of forward speed, thus slowing you down.  In theory, he is absolutely correct.  The problem is, in practice he is very likely wrong.  Depending on what you are doing with the rest of your body you may still be accelerating your board, you may be maintaining it’s speed, or you may be causing it to slow down less than it would be if your blade was already out of the water.  I’ve confirmed this with acceleration data from the GPS/accelerometer I have been using.

The basic theory is that you move your board forward most effectively when your blade is at a positive angle, and in particular when your blade is vertical.  As soon as you pass through vertical, theory has it that there is little contribution to forward movement and, because at a negative blade angle a component of the force exerted by the blade is directed up, that you are actually pulling the back of your board down into the water.  This is turn is thought to slow the board down because it does not ride efficiently in the water and is essentially going uphill.  When you pull your paddle blade past your feet it is at a considerable negative angle.  Therefore the theory maintains that pulling your blade past your feet is bad.

While I totally understand this notion and agree with it in theory, I’ve always felt that reality and theory don’t necessarily align in all aspects of a paddling stroke.  In practice I’ve found that whether you are in a sprint C1 canoe or on a SUP board it is extremely difficult to paddle without ever having a negative blade angle.  More to the point, it is nearly impossible to prevent your blade from passing your hips in canoe or your feet on a SUP board.  The way we are positioned on the boat/board, the way our joints articulate and the length of the paddle all make it totally unrealistic.  The only way to attempt to prevent your blade from passing your hips/feet is to make huge sacrifices in body weight and force loaded onto the paddle in the catch and pulling phases of the stroke.  In canoe such a sacrifice is never considered and you won’t ever see anyone good paddling that way.  It’s simply so much slower and less effective that it just isn’t done.  On a SUP board you see some people trying it with varying degrees of success, but to say it represents better technique than pulling past your feet to some degree is entirely wrong.

I’ve always felt that paddling is a game of trade-offs.  You often find that by emphasizing one thing it is at the expense of another.  What we’re talking about here is a perfect example.  The more weight you load on your blade and the more force you generate in the pulling phase of your stroke, the more likely you are to pull past your feet and have to deal with whatever negatives that brings.  Similarly the more you try to not pull past your feet, the less you can load your paddle during the pull.  You’ll have to deal with the consequences of a far weaker pull.  The reality is that each of us has to find the right balance between these two extremes that works best for us.  What I choose as optimal for me may be totally different than what you choose.  To say that one approach is better than another is both foolish and wrong.  It is right if it works for you with the fitness strengths and weaknesses you bring to the board.  However as we’re always trying to find ways to improve and go faster we should always be experimenting with that balance, trying either slightly more or less load and exiting slightly sooner or later to see if we can find a new, better, optimal balance based on our ever changing strength and fitness capabilities.

Let’s take a look at some of the data generated by the GPS/accelerometer I’ve been working with.  The graphs included here are what we are calling “Stroke Profiles” and basically represent the acceleration of the boat/board through the entire stroke.  The Y-axis represents acceleration in g’s.  I’m not sure why the guys who designed the software chose g’s instead of m/s2, but you can always multiply the g value by 9.81 to get the value in m/s2.   Anything positive on the Y-axis represents forward acceleration.  Everything negative on the Y-axis represents deceleration.  If the value is zero then the boat/board is neither speeding up or slowing down, it is simply maintaining speed.  The X-axis represents time and the curve itself represents one stroke cycle so you can easily see the relative time in acceleration compared to deceleration.   Finally each colored curve represents a single stroke.  The black curve represents the average of all the strokes.

The first stroke profile is for one of the National Team canoe paddlers.  From syncing the GPS data to video we know that the point on the far left of the graph represents the catch where acceleration begins.  Not surprisingly, acceleration increases rapidly to a peak with is pretty much the point in the stroke where the blade is vertical.   Everything past the peak on the curve is done with the paddle at an increasingly negative angle.  You can see that the boat is still accelerating forward, though at a decreasing rate than it was when it the blade was vertical.  What is interesting is that when the paddler is steering (canoe paddlers use their paddle to steer every stroke in a very modified J-stroke), the boat is maintaining speed and still not decelerating.  At this point the blade is well past the paddler's hips.  This is represented by the flat line along the X-axis.  Clearly, if you paddle well you can still generate enough pressure on the blade while steering to prevent the boat from slowing down, and you're doing it with a negative blade angle well past your hips.   Finally, where the curve falls below the X-axis the boat is decelerating.  This is the recovery phase of the stroke where the blade is out of the water.

The theory about pulling your blade past your hips/feet applies to canoe just as much as SUP.  In fact racing canoes have considerably less volume at the stern than there is at the tail of a SUP board so, in theory, it should be even more important to exit early as a racing canoe should be much more sensitive to the effects of a negative blade angle.  If you watch video of a canoe race you can clearly see the boat’s pitch change during the stroke.  The tail drops and the nose rises.  In theory this slows the boat down.   A good paddler attempts to minimize this motion but knows that the vast advantage gained by a fully loaded stroke (which means the blade passing his hips) makes this loss of speed associated with change in boat pitch negligible in comparison. 

In canoe, trial and error over the years has shown that a good rule of thumb is to exit the water before your bottom hand passes your hip.  Passing this point is going to cause too much pitch change, is going to create paddle drag (causing deceleration) and most importantly is going to delay getting to the next catch and the most effective part of the next stroke.  You’ll see some paddlers exiting with their hands right at their hips and some exiting very early with their hands by their front knee.   Wherever you exit, the blade will be further back than your bottom hand, and very likely past your hips.  Most paddlers will exit somewhere in the middle between these two  extremes.  Again, this is an example of the trade-off between loading and exit, and each paddler is trying to find their own optimal balance between the two.

I’ve contended since I first stepped on a SUP board that it is like C1 standing up.  In fact, of all the paddle disciplines I’ve tried, SUP is the most like C1.  The difference between high kneeling and standing is small enough to make the paddling position and application of forces very similar.  As such, the stroke profile for a SUP paddler should look similar to that of a C1, although we can expect the acceleration to be much lower due to the shape of the board.

Below is a stroke profile I got from putting the GPS/accelerometer unit on my own board.  The first thing you notice is how much less acceleration you get on a board compared to a C1.  The difference is dramatic.  I’ve even changed the scale on the Y-axis in the graph and it is still a shallower curve.  The canoe acceleration peaks around 0.8 g’s and the board acceleration just over 0.3 g’s.  The other thing you notice is that the board accelerates for a longer period of time.  This is understandable as my stroke rate on the board was slower than the canoe paddler's and the blade was in the water for a longer period of time.

The really important thing that the stroke profile for SUP shows us is that the board continues to accelerate while the blade is in the water.  When synced to video you see that the initial acceleration begins at the catch with the blade contacting the water.  The acceleration increases as force is exerted against the water by the blade through to peak acceleration when the blade is basically vertical.  Then acceleration decreases as the blade angle becomes increasingly negative towards the exit.  The transition from acceleration to deceleration occurs when the blade exits the water.

Again, as seen in the canoe stroke profile, the notion that the board decelerates once the blade has passed vertical is wrong.  While the amount of acceleration is decreasing, it is still accelerating in the forward direction until the blade exits the water.
  If you're comfortable pulling through that far you are not slowing your board down.  You may feel it's worth trying to get a bit more from this part of the stroke rather than rushing to the next one

Just as the bottom hand at the hip has been accepted as the maximum distance to pull the paddle through in canoe, on a stand up board I would suggest that the maximum distance should be your bottom hand at your hip or feet.  I know I exit 12 to 18 inches in front of that and still have the blade go a considerable distance past my feet.  I tend to paddle with a slightly longer paddle than most and hold my bottom hand a little higher than most, which increases that distance.  Someone with a shorter paddle and lower bottom hand might be able to pull their hand closer to their feet than me without having their blade actually travel any further past their feet than mine, but all the same it will still pass their feet.  For now, the point I want to make is it is absolutely incorrect to say that you shouldn’t pull the blade past your feet.  What is the optimal place to exit?  We’ll look at that shortly.

Setting the blade in the water before pulling

I’ve been guilty of telling people in clinics to set the blade in the water before pulling.  The idea, of course, is to make sure that you gather water behind your blade before pulling to maximize connection and, if you are someone with a splashy catch, to clean that up by eliminating  “air catching”.  The problem is that if you take too long to set the blade you actually slow yourself down. 

A good catch is aggressive and attacks the water, both gathering water behind the blade and creating pressure against that water (which begins to accelerate the board forward) almost simultaneously.  It’s really difficult to do this effectively, and as a consequence most paddlers either splash a little at the catch (meaning they have maybe lost a little connection at the catch) or they set the blade so deliberately they have a slight pause before pulling (meaning they are actually slowing the board down).  Again, it is a trade-off between the two extremes and finding the optimal catch for you takes some time and experimentation.
Let’s take a look at a stroke profile that shows this.  This is from the same canoe paddler as the stroke profile above.  The difference is that this represents paddling at 38 to 40 strokes/minute while the one above represents paddling at 65 to 70 strokes/minute. There is a big difference in how aggressively you catch the water between 40 and 65 strokes/minute, and as a result the acceleration curves look quite a bit different.

I’m not sure why the curve appears the way it does on the graph, but this curve was synced to video so there is no doubt about what we are seeing.  If you look at the far right of the graph you see a little blip of positive acceleration before negative acceleration.  The little positive blip is the result of body positioning movements and the tip of the blade contacting the water at the start of the catch.  The little negative blip is the boat slowing down again as the blade is setting in the water.  Then we move to the left side of the curve and see the expected acceleration as the paddler pulls against the set blade. 

Bear in mind that the paddler in this instance is very good and I’ve had to work very hard to be able to catch him slowing the boat down while setting his blade because he is only doing it a tiny bit.  Many paddlers, though they may pause only briefly to set the blade, are going to slow their boat/board down more.  Furthermore, I believe this effect will be more apparent on a board than a racing canoe because it is much more difficult to accelerate a board in the first place.  Gathering water behind the blade to establish connection is one of the most important things a paddler can do, however being too deliberate in setting the blade in the water before pulling is clearly something that is going to end up actually slowing you down.  It is really interesting to watch some of the world's fastest sprint canoe and kayak athletes.  Some of them have very splashy catches.  Clearly what they gain from an aggressive catch that accelerates their boat immediately makes up for whatever connection they may momentarily lose at the catch.

Determining the right technique for you

As I mentioned earlier, there are certain fundamental principles to consider in good paddling.  How each individual incorporates those principles into their own technique is really up to them.  There are some ways that I think are better than others, but at the end of the day, there are different approaches that can all yield success.  Often paddling becomes a question of trade-offs.  Do you have a heavier, more loaded stroke and maybe pull a little further past your feet, or do you have a less loaded stroke and exit earlier?  Do you attack the water really hard at the catch and perhaps splash a little or do you tend to be more deliberate at the catch and emphasize the pulling phase more?  The optimal approach is the one that works best for you and should always be developed taking your fitness capabilities into consideration.

To give you an example of different paddlers taking different approaches to paddling take a look at stroke profiles for both Jimmy Terrell and me.  Most people would think that our strokes would be very similar as we both come from a sprint canoe background and share pretty much the same philosophy when it comes to technique.  Yet when you look at our stroke profiles they are quite different.

We’ve already seen my stroke profile so let’s take a look at Jimmy’s.  He has greater magnitude acceleration than I do, but accelerates his board for a shorter period of time.  While he has a greater peak deceleration, I have larger deceleration for a longer period of time.  However my total time in deceleration in relation to time accelerating is much less than Jimmy’s.  I should point out that we used the same board for this test so the board is not a factor.   If you look at video of the two of us with the stroke profiles in hand, you can see where the difference is coming from.  Jimmy uses a shorter paddle relative to his height than me and has his hand further down the shaft closer to the blade.  This allows him to accelerate his board quickly.  However his stroke is a little shallower and less loaded throughout the pull and he exits the water earlier, losing some of the continued acceleration that the exit can provide.  If I got the sport scientists working with the National Team to run a more advanced report, that could tell us the area under the acceleration and deceleration curves and provide a relative percentage of each for each of our strokes.  That would allow us to compare our strokes more quantitatively.  

We do have some quantitative data to compare:
Ave. stroke rate
Ave. stroke distance (m)
Ave. velocity (m/s)
Peak velocity (m/s)
Peak acceleration (g)

Jimmy                                                                                                   Larry
What we can conclude from this comparison is something that Jimmy and me already knew.  He paddles in a slightly lighter gear than l do, using a slightly faster and lighter stroke.  We can also conclude from his superior acceleration that his technique is better suited to sprinting than mine, while I am probably more suited for longer distance races of 1000m and over.  It is interesting that our approach to paddling has not changed since the days of our C1 racing.  These were our relative strengths when we used to race all the way back in the 1980s.

The important thing coming from this comparison is that it illustrates that there are different approaches to moving a board fast and that each paddler needs to find the optimal approach to moving their board for them.  While there are fundamental principles you need to address to paddle effectively, there is no right or wrong technique once you’ve incorporated them.  Over time both Jimmy and I have found what works optimally for us.  What works for him isn’t ideal for me and vice versa.  We could use the GPS/accelerometer to look at Dave Kalama, Jamie Mitchell, Danny Ching or anyone else you'd care to mention.  The stroke profile of each is going to be different.  Some might be similar but they won’t be the same.  A stroke profile is almost like a fingerprint for a paddle sport athlete.   Everyone has his or her own preferred technique and load on the paddle.

Because we’ve found our optimal stroke does that mean that we don’t need to experiment with it?  Absolutely not.  I am constantly experimenting at the margins of my stroke.  Because I know I use a heavily loaded stroke, I always play with making it slightly lighter without losing the character of the stroke that seems to be optimal for me.  The important thing, if you’ve been paddling long enough to have a strong sense of what works for you, is to not attempt radical changes.  You are better off making slow, subtle changes to your technique.  Over time it will evolve and change in the way you want it to and you will be able to perhaps develop a new optimal stroke.

If you are relatively new or inexperienced and unsure of where your optimal stroke may lie I strongly suggest following the approach I’ve outlined in the “Stoke Rate in SUPPaddling” post.  It does a pretty good job of explaining the concept of gears in paddling and gives you an idea of how to determine the best gear for you.    It is really important to find a “gear” that allows you to load the paddle and pull a powerful stroke.  However it is even more important that you choose a load that is sustainable for the distance you are racing.  You absolutely do not want to develop a technique that is not sustainable for an entire race because each stroke takes too much effort.

I look at paddling like a puzzle.  There are lots of different pieces to fit together in order to paddle well and no two people are trying to solve the exact same puzzle because, since we are all different, we are all working with unique pieces.   Figuring out what all the different pieces are and exactly how they fit together is the challenge but it can be really fun.  Hopefully some of the things I’ve talked about here will help you put your own puzzle together.