Willpower training paradigms have shown limited and variable success in improving self-control.

“Willpower training paradigms have shown to shown very limited success. So for example, if again imagine you're doing the Stroop task and you're doing hundreds and hundreds and hundreds if not thousands of these trials. Another training exercise is you literally go home and you practice doing everything with your non-dominant hand as opposed to using your dominant hand. So these willpower exercises, you do them for a week and you come back. Some experiments have suggested that they do in fact improve self-control. Others say that they don't. And on average, reviews of this literature have suggested that the effect is much smaller than you might hope despite all the work that you put in. And it's very variable. So some people will see some gains, but they'll be small and but many people will see no gains.”