While willpower and ded­i­ca­tion mat­ter con­sid­er­ably in sus­tain­ing a res­o­lu­tion and reach­ing a desired goal, the per­ceived com­plex­ity of the process can have a big influ­ence on whether we are likely to achieve that goal or not.

This con­clu­sion comes from a study show­ing how the sub­jec­tive “cog­ni­tive com­plex­ity” of a diet was a major fac­tor in whether peo­ple suc­cess­fully man­aged to stick to a diet.

“For peo­ple on a more com­plex diet […] their sub­jec­tive impres­sion of the dif­fi­culty of the diet can lead them to give up on it,” reported Peter Todd, pro­fes­sor in IU’s Depart­ment of Psy­cho­log­i­cal and Brain Sciences.

[…] This effect holds even after con­trol­ling for the influ­ence of impor­tant social-cognitive fac­tors includ­ing self-efficacy, the belief that one is capa­ble of achiev­ing a goal like stick­ing to a diet reg­i­men to con­trol one’s weight.

“Even if you believe you can suc­ceed, think­ing that the diet is cog­ni­tively com­plex can under­mine your efforts.”

This agrees with the con­clu­sions drawn from sep­a­rate research show­ing how some sim­ple tricks to mak­ing suc­cess­ful res­o­lu­tions include reduc­ing our “cog­ni­tive load” and accept­ing the lim­i­ta­tions of willpower.

Willpower, like a bicep, can only exert itself so long before it gives out; it’s an extremely lim­ited men­tal resource.

Given its lim­i­ta­tions, New Year’s res­o­lu­tions are exactly the wrong way to change our behav­ior. […] Instead, we should respect the fee­ble­ness of self-control, and spread our res­o­lu­tions out over the entire year. […] A tired brain, pre­oc­cu­pied with its prob­lems, is going to strug­gle to resist what it wants, even when what it wants isn’t what we need.