The most useful study on New Year resolutions randomized 1,066 people into three groups and followed them for a full year. Published in PLOS ONE in December 2020 by Martin Oscarsson and colleagues at Stockholm University, it found that 55 percent of responders considered themselves successful at the one year mark.
That is dramatically higher than the figure you usually see quoted. The familiar claim that 92 percent of resolutions fail traces back to no identifiable study. It circulates because it is satisfying, and because January cynicism performs well.
The more interesting result in that paper is the split by goal type. Participants with approach-oriented goals succeeded 58.9 percent of the time. Participants with avoidance-oriented goals succeeded 47.1 percent of the time. Same people, same calendar, roughly twelve percentage points of difference from how the goal was phrased.
what approach and avoidance actually mean
An avoidance goal is defined by what you stop: quit sugar, stop skipping the gym, cut out alcohol, no more late night snacking. An approach goal is defined by what you start: eat fruit with breakfast, lift three times a week, cook dinner on Sundays.
Often the same underlying intention can be written either way, which is what makes this finding practically useful rather than just descriptive. “Stop eating junk in the afternoon” and “keep fruit and nuts at my desk for the 3pm slump” point at the same behavior. Only one of them tells you what to do when 3pm arrives.
The mechanism most likely at work is that avoidance goals give you no replacement behavior and no way to register success. You cannot do “not snacking.” You can only fail to do snacking, which means every day is at best a tie. Approach goals generate completions, and completions are trackable.
the support finding, which complicates the story
The Oscarsson study had three arms: active control, some support, and extended support. The group that got some support was significantly more successful than the other two. Note the direction of that: more support was not better. Extended support did not beat minimal support.
The authors are careful about interpreting this and so should anyone else, but it fits a pattern you can see in the behavior change literature more broadly. Heavy tracking and monitoring systems have a dropout problem. The apparatus becomes the work. People who log every meal in an app for eleven days and then stop have accomplished less than someone with one rule they actually keep.
Which argues against most January advice. The recommendation to build an elaborate system, buy the planner, set up the habit tracker and schedule the weekly review is more likely to produce three weeks of enthusiastic administration than a year of changed behavior.
boxing, focus and the attention argument
There is a claim worth examining in the fitness world: that combat sports train attention in a way that lifting does not, because you have to respond to an unpredictable opponent under time pressure.
The claim has some plausibility and thin evidence. Studies on open skill sports, where the environment is unpredictable, versus closed skill sports like running or weightlifting, have found some differences in executive function measures favoring open skill athletes. But these are mostly cross sectional comparisons, which means they cannot separate whether the sport built the attention or whether people with better attention gravitate to the sport. The training studies that do exist are small.
What is more solidly established is that exercise in general is associated with better cognitive outcomes, and that the specificity of the sport matters less than the dose. Boxing is genuinely engaging, and engagement drives adherence, which is the variable that actually determines whether any of this happens in March. If shadowboxing keeps you training and squatting bores you into quitting, boxing is the better program for you regardless of what either one does to your Stroop test scores.
the mantra question
Personal mantras are widespread in fitness culture and the evidence around self talk is more nuanced than either the believers or the skeptics suggest.
Motivational self talk has been shown in meta analysis to produce small to moderate improvements in endurance and precision task performance. Blanchfield and colleagues published a study in 2014 in Medicine and Science in Sports and Exercise where two weeks of motivational self talk training improved time to exhaustion on a cycling test and lowered perceived exertion. So the effect exists and it is not large.
Where it goes wrong is when the mantra becomes a substitute for a plan. “Do or do not, there is no try” is a good line and it does not tell you how many sets to do on Wednesday. The people who succeed in January are usually not the ones with the best phrase. They are the ones who decided which three days they train and then kept the appointment.
what the data suggests you should actually do
Write the goal as something you start, not something you stop. Pick a number that is smaller than you want: two training sessions a week, not five, because two is achievable in a bad week and five collapses the first time you get a cold. Attach it to a specific time and place rather than a quantity of willpower.
Accept minimal support rather than maximal. One method of tracking, not four. A note in your phone beats an app you will abandon.
And expect the trajectory to be ugly. The 55 percent who succeeded at one year were almost certainly not consistent for 52 weeks. Failing three weeks in February and resuming is the normal shape of a successful year, and it is nothing like the way resolutions get talked about in January, where any lapse is treated as the end of the attempt.