Is practice more effective if spaced over time? Example: Say Alice and Bob want to learn to pride a bike. Alice practices for an hour every day. Bob practices for 7 hours each saturday. They are both getting the same amount of practice. Which of them learns faster?

This question is about spaced vs mass learning with respect, specifically, to procedural memory. I have been able to find some research on spaced repetition of flash card memorisation, but that is declarative memory, which might be different.

Have any studies been done on this, to determine the optimal duration/spacing of practice sessions for procedural learning?
There are probably too many different possible variables here to make any broad declarations of which specific interval is most effective.

There are "between session" improvements in procedural memory, which may result from consolidation of memory especially during sleep. There can also be between session decays as learned skills deteriorate over time. Optimizing the between session change is the key factor in optimizing time spent training vs improvement.

Hauptmann et al. 2005 found that in the specific context they tested, "between session" improvements were optimized when subjects stopped training at the point of saturation of learning. That is, they practiced in one session until they stopped seeing improvement during that session to optimize the total learning per time practiced. The specific amount of time spent training before saturation was not the same for all subjects.

It isn't clear how broadly applicable this finding would be, and in the context of physically demanding tasks like sport there could easily be non-mental factors that dominate: for example, if your training saturates because you are injuring yourself, you may be physically limited in training rather than mentally limited.



Brashers-Krug, T., Shadmehr, R., &amp; Bizzi, E. (1996). Consolidation in human motor memory. Nature, 382(6588), 252.

Diekelmann, S., &amp; Born, J. (2010). The memory function of sleep. Nature Reviews Neuroscience, 11(2), 114.

Hauptmann, B., Reinhart, E., Brandt, S. A., &amp; Karni, A. (2005). The predictive value of the leveling off of within session performance for procedural memory consolidation. Cognitive Brain Research, 24(2), 181-189.

Karni, A., Tanne, D., Rubenstein, B. S., Askenasy, J. J., &amp; Sagi, D. (1994). Dependence on REM sleep of overnight improvement of a perceptual skill. Science, 265(5172), 679-682.