The Physics Of Alpine Skiing

There are few things in life more enjoyable than the adrenaline rush of flying down a mountain strapped to nothing more than a pair of boards. Cold snow runs through my veins and I cannot remember a winter when I did not ski, sled, or toboggan. My guess is that snowboards provide similar thills for their riders, but I can only provide perspective as a lifelong two planker.

Two Parts Of A Turn

People who have slid around a mountain with me know that one of favorite pop quizes is to ask my athletes: can you name the two parts of a turn? Just like anything, there are an infinite number of ways to describe an activity. My approach has always been to start with a birds eye view and to stick with the KISS principle (keep it simple, stupid). With that in mind, there are exactly two parts to any turn made with skis on a snow covered mountain:  (1) the "risk your life" part of the turn and (2) the "save your life" part of the turn. This may seem like an oversimplification to the sport, but it feeds directly into a much broader discussion about dynamic balance with investing implications. 

The "risk your life" part of the turn is the first half - where we are starting to point our skis down the hill. They accelerate (with our heartbeat) and our face may exhibit wider eyes or pursed lips. We are living life on the edge. The "save your life" part of the turn is the second half - where we are hoping to point our skis across the hill. They (eventually) slow down - along with our heartbeat as we break into a small satisfied smile. Here is another pop quiz for you: what were the computer programmers last words? Lather. Rinse. Repeat. We humans are gluttons for punishment and if we live past that first turn, we naturally want to do another...and another...and another.

The Downward Spiral

Skiing is commonly referred to as a "risk-based" sport. Many of us are very mindful of the fact that one small slip can end in serious injury. Because of this, fear can either be a great motivator - or a paralyzing roadblock. My last post mentioned fear as a four letter word in the sense that it can do more damage to a person than someone calling us all sorts of nasty names. One might think that side-to-side (or lateral) balance is the biggest risk confronting a skier as they try to keep from falling down and embarrassing themselves. The hardest part, however, is front-to-back (or longitudinal) balance. Our ankle muscles are wrapped in stiff, plastic boots that make it very difficult to flex and balance as the skis do what they were designed to do - arc a turn down a mountain. This balance becomes even more tenuous when we start to move faster down the hill or try a steeper trail. The fear-o-meter swings higher on the scale and our body mimics the proverbial deer in the headlights as our muscles tense like oak trees.

One of my favorite skiing memories was the Mount Ellen portion of Sugarbush Resort way back when it was still called Sugarbush North. We were skiing a double black named FIS off the summit chair and I noticed a small group of skiers who were tackling the volkswagen-sized moguls like they were no bigger than a pitcher's mound on a baseball field. After a few laps of being humbled by this famous trail, we tucked into the Glen House for a lunch of Vermont cheddar burgers. It just so happened that this small group of mogul masters was sitting at a nearby table just finishing up their lunch. I could not help myself from asking them what was the secret to their success on such a challenging slope. The (seemingly) leader of the posse responded: "Oh, well before skiing a trail like that, you definitely have to have one of these" - pointing to his pint of beer. It may not be true that alcohol improves our athletic skill, but there is a reason why it is sometimes referred to in skiing circles as "liquid courage." One more pop quiz (I promise this will be my last!) Q: What are every skiers last words? A: Here. Hold my beer!

A Dynamic Balance

There is (almost) no substitute for the muscle memory that comes from experience. It is easy to see the athlete who has taken countless laps perfecting their technique in the most challenging conditions. They make it look like child's play with their simple efficiency of turning around obstacles while adjusting to minute changes in the running surface. There is - in fact - a skills hierarchy that can be viewed as a pyramid. The upper levels build upon the lower levels and blending them all together is the artful part to the physics problem. Once we are proficient enough to scale the pyramid in its natural state, we take the leap of faith to turn it upside down by using our skills to manage what may be thought of as dynamic balance.

One of the beautiful things about outdoor sports is that the conditions are constantly changing. One day could be completely different from the last and the exact same trail could ski differently on the next hot lap. These changes are due to weather conditions, slider traffic, and our own specific path down the trail. Living life "on the edge" means different things for different people. The financial markets and our own portfolios are all constantly changing - requiring us to assess and adapt in order to remain in balance.