Some Physiology: Preload, Mitochondria and Endurance

Gorge-Paddle-Challenge-2013-3Like most of you I don’t have time this week (or many weeks) to put in the miles of training that could definitely build my endurance. I understand the correlation between heart rate (and the underlying volume and force of blood flow) and endurance training. During the next 8 weeks before the Colombia Gorge Paddle Challenge (8 miles down wind and a 5 mile course race) training I hope to enhance additional variables – the preload and mitochondria.

For example, when your muscles contract, they propel the flow of blood traveling through your veins and back to heart, which increases the amount of blood filling your heart (this is called a preload). This preload actually enhances the heart’s stroke volume during exercise, making adequate contraction and strength of your skeletal muscle a major determinant of your endurance performance . I’m gonna need that for both the down wind and the course race.

gorge-downwindThat’s not all. Tiny powerhouses in your cells called mitochondria use oxygen to manufacture high levels of ATP energy via the breakdown of carbohydrates or fat. So if you increase your mitochondrial density, more energy becomes available to your working muscles, which allows you to produce higher amounts of force for longer periods of time. In addition, your actual VO2max (the maximum amount of oxygen you can deliver to your muscles in a given amount of time) is a result of two variables:

1) how much blood your heart can send to your muscles (a combination of the heart rate, stroke volume and heart contractility you already learned about)

2) how much of the oxygen sent to your muscles is actually extracted from the blood and used by the muscles before the blood heads back to your heart.

Whole body (panaerobic) strength-endurance - 1987

Whole body (panaerobic) strength-endurance – 1987

In the 1980’s I was the national education director for a program called Heavyhands. It was a method of using light handweights in a variety of movement patterns that engaged about 80% of trunk, arm and leg muscles in an aerobic level. When such a large percentage of muscles were engaged and moving blood and oxygen in the body the perceived exertion at high intensity levels was less than the same intensity with fewer muscles involved (like running or cycling).

In one study (1) 4 repetitions of 4-minute runs at 90%–95% of heart rate maximum, followed by 3 minutes of active recovery, performed 3 days per week for 8 weeks resulted in a 10% greater improvement in stroke volume compared to long, slow distance training 3 days per week for 8 weeks. This is good for me because that series takes about 40-45 minutes including a cool down. It’s an easy lunch hour session 3 days a week.

Another study (2) showed that that high-intensity intervals performed at 90%–95% of VO2 max increased left-ventricle heart mass by 12% and cardiac contractility by 13% – and these are two other significant determinants of cardiovascular capacity and oxygen delivery during exercise.

Good paddling technique requires the engagement of trunk and legs in addition to arms, so it is an ideal exercise to build the fitness described above – and it is my sport! On non-paddle days I will use TRX system and a variety of Heavyhands workouts (link to come) and 3-4 days of yoga.

Engaged core and controlled movement protects back

Engaged core and controlled movement protects back

My plan for 3 times this week: (Building and mixing it up throughout the next 7 weeks until my event

-Start @ 4 x 30 seconds maximum sprints, with two to four minutes easy paddling after each sprint working on a good reach and catch,

Next I will do @4 X 90 second paddles at 85-90% HR max with 60 seconds of easy paddling after each sprint


  1. Helgerud, J., et al. 2007. Aerobic high-intensity intervals improve VO2max more than moderate training. Medicine and Science in Sports and Exercise, 39 (4), 665-71.
  2. Slørdahl, S.A., et al. 2004. Atrioventricular plane displacement in untrained and trained females. Medicine & Science in Sports & Exercise, 36 (11), 1871-75.

Shoulders, Quads, Reps: SUP Training Fun

My favorite paddle last week came on a windy day – with wind in the face while going upstream.  As I dropped my board into the Deschutes River crowded with traditional summer-time tube-floaters and all types of paddle craft I was thinking about getting a nice interval training session.  I was using my KIALOA Tiare Adjustable paddle extended almost 3 inches longer than when I used it last week for surfing.

The wind was cranking downstream while I paddled upstream

The wind was cranking downstream while I paddled upstream-

In order to monitor a bit about my training paddles I use Nike+ on my iPhone to get feedback on minutes per mile. I wear a Polar heart rate monitor because sometimes I tend to go too hard for too long and start to erase the fun factor.

The upstream/wind-in-face leg: Imagine my surprise when I heard the robo-voice from the Nike+ app say, ” One mile. Average pace 18 minutes per mile.” Okay,” I thought to myself, “When the breeze is in my face and I am going up current in this section of the river I usually average 20 minutes a mile.” Weird, I wasn’t trying so hard, my rate of perceived exertion (RPE) was medium, maybe a 6 out of 10.  Heart rate was in a manageable range. What was making a difference?

I believe I was cranking out the miles in a quick but seemingly easy manner because of two things.

First of all, I did feel powerful. My board seemed to be gaining power from my legs with each paddle – and the only thing I was doing differently was maintaining a more complete rotation of my upper body. Core engaged and tail tucked. I have been training on non-paddle days with the TRX system. A neutral spine is a prerequisite to doing the TRX program. Perhaps a regular routine of that practice at that had provided me with a better “engine.” I have had a habit of bending at the waist, particularly when skiing. Muscle and body memory around creating that more upright, neutral spine might be a valuable transfer to more than just my SUP technique.

Technique makes all the difference. I get a great deal of insight by reading Dave Kalama’s blog. He recently wrote, “Paddling most of the time needs to be a very flowing and rhythmic action, not a tense muscle flexed series of positions, but rather a constant continually moving movie. Don’t get me wrong, there is a time and a place to exert yourself, but if your base stroke comes from a place of rhythm and flow, when you exert yourself you will be much more effective and efficient. The best fix for it is to greatly reduce your power level and learn how to use your technique as your driving force, not your power output. Decrease your power to the level that you don’t feel like you’re doing any work at all, and just concentrate on technique. You’ll be surprised at how fast you go.”

Tiare Paddle In the Quiver: The team at KIALOA Paddles has lately been offering much more. On my “favorites” is the amazing Tiare paddle blade. I particularly like the adjustable shaft with a paddle blade made for especially for women. Even though the Tiare is smaller in square inches, the bottom third (where the catch takes place) is wider. This allows me to really feel and accentuate the catch of my paddle stroke – thus gaining more effective power as the stroke plays out.  In addition, Dave Chun explained that the flex of the blade allows me to “feel” the water more effectively throughout the stroke.


Kialoa Paddles Tiare is a “must have” for a woman’s quiver – demo one as soon as you can

Dave shared this in more detail, “I feel a good paddle needs to flex. The flex gives feedback to the paddler, which makes for a more efficient catch and pull. What the blade is doing in the water is important if a paddler wants to continue to develop their technique. I believe stroke technique is a lifelong journey. Many paddlers only think in terms of fitness when training. But, consider how most athletes are trained for their sport. Components of the sport are broken down in to small segments and drilled over and over again. Practicing an inefficient paddling stroke will get you fit, but it will limit the threshold of one’s overall speed.

The stiffness or flexibility of the paddle must be scaled to the strength of the athlete. Generally speaking, men are larger, and thus stronger. The typical woman, cannot “load” a blade or a shaft designed for a man. It is not simply a matter of building a blade with less surface area. The blade, as well as the shaft, must load under a woman’s energy output. 

Designed and scaled for women every step of the process: The Tiare was designed during the tooling/molding phase as a women’s paddle. The rib is narrower and lower in height than the Insanity. It was scaled to a women. On our part it was a commitment to our women’s program. The Tiare mold or “Shorty” as we nicknamed it, will never be used for an all-around or man’s paddle.

During the design phase we decided that a women’s shaft should be less than 28mm. 28mm is the standard diameter of a men’s Olympic weight lifting bar. 25mm is the standard for women. 25mm is pretty small for a paddle shaft. We settled on the 27mm-27.5mm range. Round shafts flex more than oval shaft, dimensions  and material lay-up being equal. Like designing a pair of gender specific blue jeans, we started with a clean slate when we designed the Tiare – for women.”

Simply, I am STOKED!!!! Off to about 8 weeks of training before I use my Tiare paddle in the Colombia Gorge Paddle Challenge – will we see you there? I will be testing the Tiare that is being developed for women who race by the innovative team at KIALOA Paddles. Look for us in the KIALOA Paddles tent for some “talk story” fun.