Tying a costly activity to a pleasurable one improves consistency.
You only let yourself watch the next episode of your favorite show while exercising. Temptation bundling combines an activity that's costly to do (going to the gym) with one that gives immediate pleasure (watching something entertaining), available only while doing the first one.
A field experiment at a university gym gave a group of students audio players loaded only with highly entertaining audiobooks (like "The Hunger Games"), which they could only listen to while physically at the gym. This group attended the gym significantly more often during the weeks of the study than a control group that had access to the same audiobooks at any time, and also more than a group that was simply paid to attend.
Self-control fails us for lack of motivation in the moment, even though we know we should exercise. Bundling the temptation turns the immediate pleasure into the very reward for doing what's costly, instead of leaving the real benefit for a distant, abstract future.
Source: Milkman, K. L., Minson, J. A. & Volpp, K. G. M. (2014). Holding the Hunger Games Hostage at the Gym: An Evaluation of Temptation Bundling. Management Science, 60(2), 1500-1515.
Restricting access to a pleasurable piece of content or service (a podcast, an entertainment app) to only while doing the habit that's harder to sustain is a cheap and underused product design lever outside academia.
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