RESUMO
Objective: The Köhler effect is a social-psychological group motivation gain phenomenon that has been successfully adapted to video-based exercise games (exergames) using human partners. This research then shifted to using software-generated partners (SGPs), providing greater flexibility and adaptability to manipulate the game environment to be most motivating for the user. However, recent SGP-based experiments have demonstrated a diminished motivation gain effect. Extending previous work with human-human partners, this experiment varied the perceived exercise ability of the SGP as a potential motivation gain effect moderator on the participant's exercise persistence. Materials and Methods: Male and female college students (n = 176; mean age, 21.5 years) completed two series of abdominal plank exercises using an exergame developed specifically for a previous Köhler study. Participants completed the exercises individually and, after a rest, were randomly assigned to complete the same exercises again alone or with one of three SGPs: low ability discrepancy partner (LP), moderate ability discrepancy partner (MP), and high ability discrepancy partner (HP). Results: A 2 (sex) × 4 (condition) analysis of covariance main effect for Condition was not significant after controlling for Block 1 times (P = 0.093). However, contrast estimates of plank persistence times between the MP condition and individual no-partner control were significant, P = 0.014, 95% confidence interval [4.34-37.68]. There were no other significant condition persistence differences. Conclusions: A moderate discrepancy between the participant and the superior nonhuman partner is more motivating in a conjunctive task paradigm than exercising alone or with an SGP that is low or high in ability discrepancy.