Milkman, Minson & Volpp (2014): Temptation Bundling
Milkman, Minson and Volpp coined temptation bundling: pairing a should behaviour, like exercising, with a want behaviour, like a gripping audiobook, and allowing the want only during the should. In a field experiment at a university gym, participants whose audiobooks were locked to the gym attended more often than controls early in the study, and afterwards 61 percent of participants said they would pay for gym-restricted audiobook access. The effect decayed over the semester, which is itself an honest and useful finding.
| Citation | 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), 283–299. |
|---|---|
| Study type | Randomised field experiment over roughly ten weeks |
| Key finding | Full bundling (gym-only iPod with tempting audiobooks) raised gym visits versus control early on; effects declined over time |
| Willingness to pay | 61% of participants said they would pay for gym-restricted access to tempting audiobooks |
| Sample | 226 students and staff at a university fitness facility |
What the study found
Participants were randomised into three groups: a full treatment whose loaded iPods with tempting novels were physically available only at the gym, an intermediate group encouraged to self-restrict their own audiobooks to workouts, and a control given a gift card. The full treatment initially attended the gym substantially more than control, with the self-restriction group in between. The advantage eroded across the semester, dropping sharply after a Thanksgiving break, but the closing survey showed real demand for the mechanism: a majority would pay to have the restriction imposed.
Why it matters
Temptation bundling attacks the procrastination equation from the value side: it imports immediate pleasure into a task whose rewards are otherwise distant, so the aversive activity can win the in-the-moment contest. It is cheap, self-administered and honest about human nature, using a temptation rather than fighting it. The decay result carries its own lesson: bundles need refreshing, a new series, a new pairing, and breaks in routine are when they die.
Caveats
This is one field experiment at a single university gym with 226 mostly young, gym-registered participants, so generalisation to other behaviours and populations is assumed rather than shown. The headline effect faded over weeks and did not survive the holiday break, and a larger 2021 follow-up by Milkman's group found only modest average effects of a lighter-touch bundling intervention. Bundling is well grounded in theory and worth trying, but it is a boost, not a cure.
Peer-reviewed randomised field experiment in Management Science.
Related
Temptation Bundling (how to use it)Present bias
Frequently asked questions
Does temptation bundling actually work?
In the original experiment, yes at first: gym-locked audiobooks raised attendance versus control, and most participants valued the restriction enough to say they would pay for it. The effect faded over the semester, so treat bundling as a starter motor you occasionally refresh rather than a permanent fix.