Schedule random practice for retention goals, blocked practice only for initial acquisition

Use blocked repetition to learn a new movement or concept, then immediately shift to random practice once the basics are present.

Why it works

The research does not say blocked practice is useless — it is often the appropriate introduction to a completely new skill, where enough blocked exposure builds the initial representation that random practice requires. The mistake is staying in blocked mode too long. Once the basic schema exists, blocked practice stops building the long-term representation and starts maintaining a temporary one, while random practice continues to strengthen long-term retention.

How to do it

1. For a brand-new skill, use blocked practice (3–5 focused repetitions) to establish basic competence.
2. As soon as errors become occasional rather than frequent, switch to random/varied practice.
3. Treat the shift to random practice as a sign of progress, not a sign of inadequate blocking.
4. Return to blocked practice only when a genuinely new element is introduced.

Evidence

Multiple contextual interference studies have identified the transition point: once novices have acquired a basic representation, random practice accelerates long-term retention; for complete novices with no schema, some initial blocking helps. Hall, Domingues & Cavazos (1994) showed this transition in a baseball batting study with expert-novice comparisons. (rct)

The exact point at which blocking should give way to random practice is not precisely defined and varies by skill and individual; the heuristic of "once errors are occasional" is an approximation.

Sources

• Hall, Domingues & Cavazos (1994), Contextual interference effects with skilled baseball players, Perceptual and Motor Skills

Common mistake

Staying in blocked practice indefinitely because it feels productive (fewer errors, more flow), when the real retention gain requires the discomfort of random practice.