Periodisation is the deliberate organisation of training across time. Rather than training the same way every week indefinitely, periodisation arranges training variables — volume, intensity, and the specific qualities being developed — in a structured sequence designed to maximise adaptation while managing fatigue.

The underlying logic is that the body doesn't adapt equally to all stimuli at the same time. Different training qualities — strength, hypertrophy, power, endurance — require different training conditions to develop, and those conditions can interfere with each other if all are pursued simultaneously at high intensity. Periodisation is the attempt to organise those priorities across time rather than competing for them within each session.

Three models are most commonly discussed. They differ primarily in the timescale over which variation occurs.

Linear periodisation

Linear periodisation increases intensity progressively over time while reducing volume. A classic structure starts with high-volume, moderate-intensity work in the early weeks — developing work capacity and muscle size — and transitions toward lower-volume, high-intensity work that builds strength and neural efficiency.

The logic is sequential: build the base first, then express it. A bodybuilder or powerlifter might spend 8–12 weeks in a hypertrophy phase (higher volume, moderate loads), then transition to a strength phase (lower volume, heavier loads) as a competition or peak approaches.

Linear periodisation is simple to understand and implement. Its limitation is that qualities developed in earlier phases begin to decline by the time later phases begin, which is more of a concern for advanced athletes than for most recreational trainees.

Undulating periodisation

Undulating periodisation — also called non-linear periodisation — varies volume and intensity more frequently, either within a week (daily undulating periodisation, or DUP) or between weeks (weekly undulating periodisation).

Rather than progressing through distinct phases, each training week might include sessions targeting different qualities: one session focused on heavy loads and low repetitions for strength, another at moderate loads and higher repetitions for hypertrophy. The variation prevents any single quality from declining while another is being emphasised.

Research comparing linear and undulating models finds comparable results for most outcomes in recreational trainees. Undulating periodisation may provide a practical advantage in sustaining motivation through variety. Some evidence suggests it benefits more experienced trainees who have adapted to the predictability of linear progressions.

Block periodisation

Block periodisation organises training into concentrated phases — called blocks — each targeting a specific quality. A typical structure might include three blocks of 3–4 weeks each:

  • A hypertrophy block with high volume and moderate intensity
  • An accumulation/strength block with lower volume and higher intensity
  • A realisation/peak block with very low volume and very high intensity

The key feature of block periodisation is that each block develops a residual quality that the next block builds on — hypertrophy provides the structural base for strength, which provides the base for peak power expression. It was developed primarily for competitive athletes and tends to be most relevant for people training with specific performance goals.

Which model to use

The honest answer, supported by research: for most recreational trainees, the differences between models are smaller than they appear in the literature. Any periodised approach — one where volume and intensity change in a structured way across time — outperforms training that stays completely consistent. The specific model matters less than the principle of deliberate variation.

The most useful question is not "which model is better" but "which model fits my goals, schedule, and training history." For a recreational lifter training twice a week with general health goals, simple linear progression with occasional deload weeks is entirely sufficient. For someone training four or more times per week with specific performance goals, more structured periodisation becomes increasingly relevant.