Think of your hypothalamus as the Goldilocks of your brain. This hormonal control center responds when the body’s core temperature, like the Three Bears’ storied porridge, is too hot, cold or “just right.” Good thing, too, because most people can only function within ± 1 degree Celsius (cyclists, runners, hikers, paddlers and, yes, even climbers included).
THERMAL STRESS occurs in either direction as the core is protected by increasing blood flow nearly 2.5 times in the cold and pushing 15X the volume to the skin in the heat. The challenge for the outdoor athlete is to manage this delicate balance and stave off even early-stage hypothermia or hyperthermia.
Enter the vest. A living relic of the Middle Ages once popular with clergy and the titled, the vest’s primary mission is to guard the core against the perils of cold, wind and wet. Lighter than its embroidered and bejeweled ancestors, today’s vest serves at least three vital purposes with or without a shell.
1) STABLIZE CORE TEMPERATURE AT THE BEGINNING AND END OF ACTIVITY. Before the outdoor athlete’s engine heats up, the vest protects the core to ensure hands and feet remain nimble. As strenuous activity comes to a close and exhaustion approaches, the same benefit is delivered.
2) MANAGE TEMPERATURE AS CONDITIONS FLUCTUATE DURING ACTIVITY. A thousand foot elevation change, light rain or piercing sunlight change the game. With little weight and minimal space required, the vest is an at-the-ready equalizer as hypothermia can pounce at any core temperature under 98.6o.
3) GIVE A BOOST TO OTHERS ON THE WATER, ROAD OR TRAIL. Mostly free of the tighter sizing requirements of shells, the vest is a way to keep fellow travelers safe, comfortable and having a great time. Easily shared and hard to lose, the vest can literally save the day.
A wide range of choices makes vest selection challenging. Answer three questions and you’ll quickly shed the less-suitable options.
a. Is this vest about insulation, wind protection, water repellency or a combination of factors?
Patagonia’s Micro Puff Vest (MSRP $129) delivers windproof insulation and a water-resistant shell at 10 ounces. Pearl Izumi’s Barrier Vest collection (starting at MSRP $70) lets cyclists stand up to both wind and water.
b. Do I need pockets and extra features or is simple better?
Columbia’s Silver Ridge™ Vest (MSRP $65) is a canvas and fleece piece covered in well-organized pockets and flaps suited for photo missions or lodge-launched excursions. Basic fleece vests eliminate extras and preserve cash starting at under $50 (New Balance and others).
c. Will weight and storage space be at a premium?
GoLite’s Dakota Wind Vest for women tips at 2 ounces (MSRP $70), and Marmot’s DriClime® Vest (MRSP $80) is a versatile travel companion at 6 ounces. Here, specialization contributes to reduced weight and space.
Help your hypothalamus keep away the Umbles that signal hypothermia; Stumbles, Mumbles, Fumbles and Grumbles. Adding one or more well-chosen vests keeps the legs pumping, arms pulling and grins coming even as conditions change by the hour.
The intrepid explorer Goldilocks would be proud.
Sources: United States Search and Rescue Task Force, Iowa State University and University of Texas Athletic Department