In the world of resistance training, countless variables can be manipulated to stimulate muscle growth. From load and volume to exercise selection and rest periods, each element plays a crucial role. However, one variable often misunderstood and underutilized is time under tension (TUT).

While many lifters focus on the weight they lift or the number of repetitions they perform, the duration for which a muscle is actively contracting under load is a powerful, science-backed determinant of hypertrophy.

Mastering the art of TUT is not about simply moving slower; it’s about a strategic, intentional approach to maximizing the stimulus for muscle growth. This article will provide a comprehensive, evidence-based guide to understanding and applying TUT for optimal hypertrophy.

The Science of Hy

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