Shared Participation in Activities 343 reported substantially stronger correlations with relationship quality for activities that are intensely interactive between partners versus those that are passive, parallel, or merely in the company of others. Hill (1988), in finding a strong overall link between shared activities and marital stability, reported the strongest effects for shared “recreational activities," all of which were somewhat active and challenging (such as" outdoor activities, active sports, card games, and travel"[p. 447]). Focusing specifically on shared participation in “exciting" activities, and using both newspaper and door-to-door surveys, Aron and colleagues (2000, Studies 1 and 2) reported strong correlations with relationship quality.

Several experiments have examined the causal direction of the association of novel and challenging activities and relationship quality. Reissman, Aron, and Bergen (1993) presented members of married couples with a long list of activities and instructed them to indicate for each how “exciting" and how" pleasant" it would be to do with the partner. Activities typically rated as potentially highly exciting, but not also rated as highly pleasant, included skiing, hiking, and attending concerts and plays—activities that for most couples are novel and challenging but may be experienced as less than optimally" pleasant" perhaps just because of their novelty and challenge, which may create some tension, or just concentration. Activities typically rated as potentially highly pleasant, but not also rated as highly exciting, included seeing friends, going to movies, and eating out-activities that for most couples are enjoyable but mundane. After they had completed the activity listings, couples were randomly assigned to one of three conditions: an exciting activity condition, a pleasant activity condition, or a waiting list control condition. Couples assigned to the exciting or pleasant condition were instructed to engage in an activity from an individually constructed list appropriate to their condition for at least 1.5 hours each week for 10 weeks.(For example, the exciting activity condition list consisted of activities each of which both members of the couple had independently rated as highly exciting but only moderately pleasant.) Compliance was monitored weekly. Nearly all couples carried out the tasks as instructed. Prior to the activity listing and again at the end of 10 weeks all couples completed a standard measure of relationship quality. The results revealed that couples in the exciting activities condition had significantly greater increases in relationship quality when compared to couples in the pleasant activity or no activity control conditions.(The pleasant activity and control condition couples were not significantly different.) To test these encouraging results in a more controlled setting, Aron and colleagues (2000, Studies 3-5) conducted three laboratory experiments with couples recruited from the community. In these experiments, couples were tested on standard measures of experienced relationship quality before and after participating in structured activities designed to be either novel and challenging or enjoyable but mundane (ie, less novel and challenging). In the