Friday, August 27, 2010

The Tao of Triathlon

I recently read a few articles by Shane Eversfield I found through an email from USA Triathlon. I often write about about the physical, spiritual, and mental aspects of endurance training. I asked him for a guest post, as I feel he has a lot of insight to offer.

Movement patterns profoundly affect the brain's function. Case in point: I practice T'ai Chi daily. Using a book briefly in the beginning to "estimate the basics", I have continued to practice and refine the movements on my own for over 30 years now. Primary guidance comes from a diligent quest for perfect balance and orientation - a deep challenge as I move very slowly through the form, often with my eyes closed. After 8 years of self-guidance, I read a book about Taoism, an ancient Chinese way of life inextricably linked to T'ai Chi. The yin-yang symbol? Taoist. It expresses the cosmic dance of polar opposites - essentially, the animation of our universe. Not really a religion, or a philosophy, "Tao" translates as "the Way". Engaging an inquisitive "beginner's mind", the Taoist disciple embarks on a lifelong quest to investigate functional principles of our universe and to diligently train their application. Taoism is a way of perceiving, responding to and moving through the world around us. So is Triathlon.
As I read this book on Taoism, I realized that I was... well, Taoist. This didn't happen from reading ancient texts or from living in a remote Chinese village with Taoist sages. (Heck, I was a young hippy-artist living in the northeast US.) My Tao transformation occurred through the movements of T'ai Chi. Taoism is now intrinsic to the way I think, perceive and respond - to the way I live. So is Triathlon.
As triathletes, we're on a path to enjoy and master three basic activities from childhood. Each of these involves a repetitive movement pattern, coordinating opposite arm and leg movements through pelvic core stabilization. (Yes, even cycling.) Equally important, each of these childhood activities requires a unique and complex orientation with gravity. This is profound, given that up to ninety percent of your neurological energy is invested in balance - orienting your body to gravity. (Contemplate balance and orientation deeply while you train.) Like T'ai Chi, each of these basic childhood activities affects the way we perceive and interact with ourselves and the world. Put ‘em together, and you've got a powerful kinetic trinity. Tao of Triathlon.
Just like juggling, triathlon is a feat of timing, dexterity and balance, dynamically orchestrating three elements. Training effectively towards ambitious performance goals requires vigilance and honesty in the ongoing assessment of one's strengths and weaknesses. It demands a continuous response that is equally evidence-based science and creative intuition. Humility, self-honesty, curiosity and knowledge are essential.
Human nature provides us with nesting instincts; we gravitate towards our strengths, stay within the comfort zone, and avoid the dark forests of uncertainty. Well, there's no "nesting" in multisport. We're all familiar with that humbling "day-of-reckoning" feeling on race morning, as we toe the line with pale, tender feet. I wonder, is that what makes us so friendly and cooperative in the transition area before the big showdown?
Tao says embrace vulnerability and imbalance as opportunities for improvement well ahead of race day. Triathletes who are weak cyclists often elect to participate in group rides with experienced road cyclists. Criticism, embarrassment and humility be damned, the rewards of experience gained outweigh the rookie's discomfort. Drop the fear; embrace uncertainty as the ultimate opportunity.
In the real world, versatility ultimately triumphs specialization: Change is inevitable.
Beyond the relentless quest for swimming, biking and running mastery, experienced triathletes know there is a fourth element in triathlon: the art of transition. More than a quick gear and clothing change; it's an instant transition from sleek efficient swimmer, to strong efficient cyclist, to swift efficient runner. In under a minute, it's possible to transform from one movement pattern, from one orientation with gravity, from one integration with equipment to another one entirely.
Athletic excellence in a single sport trains mastery of a single identity. The swift transitions of multisport challenge the athlete to fully engage, and then completely detach from each identity. Ego is the collection of identities one assumes in the roles of every day life. A well-balanced individual chooses his/her identities functionally - as tools in a constructive, brilliant life. Dis-functionality is a strong attachment to a specific identity, an unwillingness to let go of one role when it no longer serves in the moment.
A ludicrous example of such an attachment: Tommy Triathlete rolls into T2, fastest bike split of the day, and transitions to run. However, Tommy just can't let go of his prowess as a cyclist and insists on wearing bike shoes and carrying his bike for the entire run. Even with the fastest bike split, that finish line is a long way off lugging a bike. Multisport transition develops a functional relationship with ego through the capacity and the will to engage and detach.
Function and brilliance - Tao of Triathlon: Swim, bike, run. Balance, orient, transition.
This article originally appeared in Hammer Nutrition Endurance News, Issue #69. Copyright 2010 Shane Eversfield

Check out Shane's book, Zendurance. Shane also writes regularly for Total Immersion, a popular system for teaching swimming.

Sunday, August 1, 2010

Infared -vs- Thermal Junction Temperature Sensing Part 2

Thermal Junction/Thermocouple Sensing

                Typical semiconductor based temperature sensing is based of current flowing through some sort of thermal junction. This junction is ideally two dissimilar metals, where the voltage will be proportional to the temperature of the environment, after taking into account time lag of heat absorption.

Voltage/Temperature Relationship

                Typically there is a nonlinear relationship, and the main limitation is accuracy. “System errors of less than one degree Celisius can be difficult to achieve.” The relationship between the temperature difference and output voltage of a thermocouple is derived from a comples summation of coeffeicients based on metal type, and results in a typically non-linear relationship.

K Type Thermocouples

Type K Thermocouples are the most common general purpose TCs used. They are made of a chromel-alumel junction with a sensitivity of approx. 41uV/ C. According to the Omega NIST reference, K type thermocouples have a maximum error of 2.2C with 0.5C being more typical.

Cold Junction Compensation (CJC)

Usually, to calibrate a thermocouple, a method similar to sound noise cancellation is used. An independent junction is maintained at a fixed temperature. More commonly a thermistor, or diode (like a PN where the current varied minutely with temperature) is used. Frequently as well, temperature sensors and a look up table can be used to extract the CJC temperature indirectly.
Some examples, and a thorough treatment of circuits for this purpose are included in the Maxim Application Note cited below “Implementing cold-Junction Compensation in Thermocouple Applications.”


                Thermocouples have a very non-linear relationship to temperature. they are versatile, and usable for measurements which will frequently cover a large range. They are more commonly used in industrial applications where such temperature variation is more common.
                 For more accurate measurements, it is common to use a resistance thermometer, which are commonly referred to as RTDs, and made of platinum. For applications under 600 degrees C they are slowly eroding the use of thermocouples due to dramatically improved accuracy and repeatability.