Vasoconstriction
The narrowing of blood vessels, reducing blood flow to specific areas. A response to cold (conserving heat), stress (directing blood to essential organs), or injury (limiting bleeding).
Used in the Books
This term appears in 3 chapters:
"...sized region in your brain that acts as your body's thermostat. The hypothalamus triggers shivering (generating heat through muscle contractions) and vasoconstriction (reducing blood flow to your skin to conserve heat). Your temperature rises. The thermoreceptors detect this."
"... beneficial, 14+ sessions/week (overtraining) harmful Cold exposure (thermal stress): - Core temperature drops during cold immersion (shivering, vasoconstriction) - Adaptation: Brown fat activation (nonshivering thermogenesis), improved insulin sensitivity - Dose-response: 10-15 minutes at 50°F beneficial, 60+..."
"...The control system**: - Too hot: Vasodilation (vessels open, maximum flow, maximum cooling) - Optimal: Partial flow (maintenance cooling) - Too cold: Vasoconstriction (vessels close, minimal flow, heat retained) The Toucan can modulate heat loss from 5% to 60% of metabolic heat production just by controlling bill ..."
Biological Context
In cold conditions, vasoconstriction in extremities reduces heat loss through the skin, conserving core temperature at the cost of cold fingers and toes. The opposite response, vasodilation, increases blood flow for cooling or healing.
Business Application
Organizational vasoconstriction: reducing resource flow to peripheral activities during stress, concentrating resources on core functions. Companies in crisis constrict—cutting marketing, R&D, and expansion to preserve cash for essential operations.