Do novel, moderately challenging activities together
New and slightly difficult shared experiences restore the self-expansion that keeps closeness alive.
Why it works
When two people do something novel and moderately challenging together, they both expand — acquiring new capabilities and perspectives. The brain associates this expansion experience with the partner who was present, restoring the early-relationship "glow" that came from rapid natural expansion. The key variables are novelty and mild challenge: familiar, easy activities do not produce the same effect even if enjoyable.
How to do it
- Identify activities that are new to both partners (or new to one and taught by the other).
- Choose something with mild challenge — not terrifying, but requiring some effort and focus.
- Schedule a specific date and time; "we should do something new" rarely happens without scheduling.
- After the activity, spend a few minutes discussing what was new or surprising about the experience.
Evidence
A key series of experiments found that couples who engaged in novel, arousing activities together reported greater relationship satisfaction compared to couples who engaged in pleasant but familiar activities, with the effect attributed to the self-expansion mechanism. (rct)
Studies have primarily used short-term experiments with couples; the long-term sustainability and mechanisms across different relationship types are less studied.
Sources
- Aron, Norman, Aron, McKenna & Heyman (2000), "Couples’s shared participation in novel and arousing activities and experienced relationship quality", Journal of Personality and Social Psychology
Common mistake
Choosing activities that are novel to only one partner (a favourite hobby one person shares), which produces expansion for the learner but not for the teacher, and can create an asymmetry.
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More practices for Self-Expansion Model: How Relationships Grow (and Stagnate) Us
- Practise including the other person in your self-concept
Close relationships develop when you genuinely incorporate the other’s perspectives and resources into how you think — not just spend time with them.
- Pursue personal growth that you share — not parallel but joint
Growing alongside a partner or friend, rather than separately, leverages the self-expansion mechanism for both people simultaneously.
- Audit current relationships for expansion rate
Relationships that stopped expanding tend to feel stagnant — a periodic audit reveals where the growth has stopped.
- Use structured escalating self-disclosure to accelerate closeness
Closeness can be deliberately generated through mutual, gradually deepening disclosure — not just through time.
- Protect expansion by resisting the slide into pure comfort
Long relationships naturally slide toward comfort and predictability — expansion requires deliberate re-injection of novelty.
- Apply the self-expansion framework to individual growth, not only relationships
The same motivation that drives relational closeness also drives individual meaning — seeking growth for its own sake.