Holding the Hunger Games Hostage at the Gym: An Evaluation of Temptation Bundling

This field experiment by Milkman, Minson, and Volpp introduces "temptation bundling," a commitment device that pairs a tempting "want" activity (listening to captivating audiobooks) with a beneficial but under-engaged "should" behavior (exercising), by restricting gym-goers' access to the audiobooks to only the gym. Participants were randomly assigned to full treatment (gym-only iPod access to tempting audiobooks), intermediate treatment (encouraged self-restriction), or control. Full and intermediate treatment participants initially visited the gym 51% and 29% more often than controls, though the effect faded over time, notably after a Thanksgiving break interrupted gym access. After the study, 61% of participants chose to pay for continued gym-only access to the audiobooks, indicating real demand for this type of self-control device. The authors conclude temptation bundling is a low-cost way to simultaneously address overindulgence in "wants" and underengagement in "shoulds," though its effects diminish following periods of forced abstinence.