Interleukin-6

Interleukin-6 (IL-6) is a pleiotropic cytokine and the prototypical exercise myokine, released in large amounts from contracting skeletal muscle to mobilise glucose and fatty acids and to orchestrate the subsequent anti-inflammatory cytokine response. Salivary IL-6 reflects acute muscular workload and the inflammatory-metabolic signal of exercise, scaling with exercise intensity and duration. Wenzel et al. (2026) and Lindsey et al. measured salivary IL-6 within multi-omics monitoring of training strain and acute fatigue.