Strength and hypertrophy are related but physiologically separable adaptations, not two points on one line. Strength = physiology (neuromuscular force production) + mechanics (technique/biomechanics) — the Two-Component Model of Strength. Evidence cited: powerlifters are on average stronger than bodybuilders despite carrying less muscle mass.
Muscle protein synthesis requires autophagy (breakdown of damaged/unneeded protein) as a prerequisite step — recovery is a full breakdown-and-rebuild cycle, not only a building phase.
Myonuclei act as distributed growth-control centers. Satellite cells (dormant, on the fiber periphery) activate and donate additional nuclei in response to training stimulus (myonuclei accretion), expanding a fiber's nuclear domain and enabling continued size increases over years. After detraining, muscle regrows faster on a second cycle — this "muscle memory" is attributed to epigenetic changes retained in myonuclei (the nuclei "remember" the growth sequence), not simple preservation of nuclei count. Emerging evidence suggests myonuclei show functional specialization (shape/position tied to jobs like mitochondrial regulation vs. injury repair) — a possible but not yet actionable explanation for individual recovery variation.
Endurance training activates AMPK, which inhibits mTOR via TSC2 — a molecular explanation for the crossover interference effect. See Hypertrophy Programming for the practical framing (primarily an energy-availability/recovery-debt issue, not a fundamental incompatibility).
Related: Strength & Power Training Protocol, Progressive Overload, Nine Adaptations Framework, Andy Galpin — Training & Metabolism System
Source: Dr. Andy Galpin, Huberman Lab Guest Series — Optimal Protocols to Build Strength & Grow Muscles.