Among elderly, the use of serious games steadily increases. Research shows that anthropomorphising digital agents (i.e., ascribing human characteristics to them) has positive short-term consequences on interactions with digital agents. However, whether these effects can also be observed over a long-term period and in a real-life setting is unknown. In two studies, we investigated the important long-term consequences of anthropomorphism among older adults (age > 50) to increase involvement in serious games. Participants read either a story that highly anthropomorphized the digital agent of a training game, or a low anthropomorphism story about that agent. To investigate long-term effect, they played the training game for three weeks, and gaming data was assessed (number of games played, time of playing, points gained). While on the short-term, the anthropomorphic story increased the humanness of the agent (Study 1), no long-term effects where found (Study 2). Furthermore, an anthropomorphic story had no influence on the gaming outcome. Our results inform app developers about which techniques are useful to humanise digital agents.