Insulin Sensitivity
topic
Exercise improves insulin sensitivity through multiple mechanisms — GLUT4 translocation (the insulin-independent glucose transport that muscle contraction activates, enabling glucose uptake without insulin signaling), AMPK activation (the energy sensor that improves insulin receptor signaling), increased muscle mass (more glucose disposal capacity), and reduced visceral adipose tissue (the primary source of free fatty acids and adipokines that drive insulin resistance). Aerobic exercise produces acute insulin sensitivity improvements lasting 24–72 hours; resistance training produces more durable structural improvements through muscle mass accretion.
Role
Exercise-induced insulin sensitivity improvement is the most powerful available intervention for type 2 diabetes prevention and reversal — yet it is the intervention most insufficiently prescribed in diabetes management, with 150 minutes of weekly moderate exercise recommended as an adjunct to dietary management and pharmacological treatment, rather than as the primary intervention whose metabolic effects are most directly addressing the physiological defect. The person with prediabetes who combines aerobic and resistance exercise with dietary modification has access to an intervention with documented efficacy for reversal that pharmaceutical interventions merely manage.