How Being “Soft” and Teeth Chattering Have Real Effects on Running Performance

The abrasive cold and wet conditions during last Monday’s Boston Marathon got me thinking and trying to find any actual science behind How Being “Soft” and Teeth Chattering Have Real Effects on Running Performance”Maybe becoming “soft” as an athlete as Bill Bowerman puts it, in regards to performance isn’t just as simple as maintaining a ‘tough as nails’ mentality.  Perhaps, there is some actual science that we can apply and re-assure ourselves with here.  Perhaps too, with scientific knowledge pertaining to ‘Shivering Thermogenesis’ and ‘Cold Exposure on Fuel Utilization in Humans’, we as runners can be a little more forgiving of ourselves when we bonk during a race that has us exposed for three to four hours.

I did a quick Google search on the effects of cold weather on athletic performance and this what I came up with for reputable and science-based theory.

Theory 1 on Shivering – Why Do We Shiver?  

My Google search first took me to – The National Center for Biotechnology Information.  I found two articles pertaining to why our bodies shiver in the first place and how that correlates to an overall loss in core body temperature.

The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.

In a nutshell, which you already know, our bodies shiver when we’re cold.  To be more specific though, it is an anatomical survival response to keep us alive and maintain body temperature for vital organs and systems to keep functioning.  Thus, our skeletal muscles start to rapidly contract and burn calories, which in this instance is the bodies form or unit of heat energy.  Read more on Shivering thermogenesis in humans: Origin, contribution and metabolic requirement.

Theory 2 – How Does Cold Weather Deplete our Bodies Fuel Sources?

Once our muscles start to engage in these bursts of rapid-fire mini contractions, the muscles begin to produce heat energy.  And as with any burning of ‘calories’, our body must resource fuel stored from somewhere within our bodies.  The chosen form of fuel for shivering seems to be plasma glucose (sugar or carbohydrates stored within the blood), muscle glycogen (carbohydrates stored within muscle tissue) and lipids (fat-like substances found within the bloodstream).

So, let’s pause here and consider the runners in this year’s Boston Marathon with weather conditions including rain, cold temperatures and gusty winds.  Some of you have first hand experience with the finesse it takes to balance running for long durations of time and having to consume calories in some form during the effort to offset the calories your burning while you’re running.  Take additional consideration into, what we’re talking about here with shivering and how this becomes a quickly understood equation for the dreaded “bonk” or as we runners know it…”hitting the wall”.

To bring the ‘elites’ down on a more human playing field with the rest of us, there were a few that admitted that the weather that day did not play into their favor and quote “depleted glycogen stores”.  Plain and simple, there was nothing left in the tank.

If you’re more of a visual learner, here is a Wind Chill Chart and some data to consider from The National Weather Service .

The NWS Wind Chill Temperature (WCT) index uses advances in science, technology, and computer modeling to provide an accurate, understandable, and useful formula for calculating the dangers from winter winds and freezing temperatures. The index does the following:

  • Calculates wind speed at an average height of 5 feet, the typical height of an adult human face, based on readings from the national standard height of 33 feet, typical height of an anemometer
  • Is based on a human face model
  • Incorporates heat transfer theory based on heat loss from the body to its surroundings, during cold and breezy/windy days
  • Lowers the calm wind threshold to 3 mph
  • Uses a consistent standard for skin tissue resistance
  • Assumes no impact from the sun, i.e., clear night sky.

Theory 3 – If Your Teeth Are Chattering  It Doesn’t Mean You’re “Soft”.  (The Real Effects of Cold on Our Running Performance)

There were several other websites that I took the time to read thru and have attached them down below for your reference too (if you choose to geek out like me).  I am now thoroughly convinced that shivering and teeth chattering is not just my bodies way of trying to tell me it’s cold and that it is going to be tapping into some calories to stay warm, but there is scientific research to back up why we sometimes feel “soft” when confronted with bad weather.

Muscular endurance, defined as the ability to sustain continuous contractions at submaximal intensity, may be altered by cold-air exposure.  -Human

Thermoregulation – On exposure to cold air the first response action is peripheral vasoconstriction, followed by shivering and hormonal release (Patton., 1988) – DNA Sports

So, let’s be constructive with this knowledge and set ourselves up for success the next time Mother Nature decides to be a party pooper.  Windbreaker (check), Dri-Fit or moisture wicking layers (check), and an extra pack of sport beans (check).  HA!  Us runners aren’t going down that easy!

Happy Fri-Yay everyone!  And hopefully wherever you’re at geographically, the weather will allow you non “soft” or teeth chattering long run conditions this weekend.


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