ABSTRACT
The other day, a friend told us about her partner and the difficulty he has to do more physical exercise. Our friend was surprised. Her partner greatly enjoyed playing tennis, and he felt good afterwards. Moreover, he was a good tennis player, knowing how to win a game even when playing against competent opponents. But then, when there was time to play tennis, he was doing everything else but arrange for a tennis match. Even when she reminded him how much he likes to play tennis and how good he would feel afterwards, and about the disappointment he experiences when staying physically inactive, this did not have much of an effect. So she felt at a loss, and so did her partner. In this chapter, we will argue that even when people are highly motivated to change their behavior, they need self-regulation tools to translate motivation into action. We will discuss two of these tools (i.e., mental contrasting and forming implementation intentions), how effective they are in achieving behavior change, and the psychological mechanisms on which these effects are based.
