Jeremy Allen
Behavior change is something I think about a lot. I am not a novice to fitness endeavors. I have been a runner for 25 years and a martial artist for 8 years practicing Brazilian Jiu-Jitsu. I am dealing with a herniation of of my S1, which happened about 2.5 years ago. It is mostly recovered, but my fitness habits were completely disrupted and proven to be fragile. I wanted to explore the best science based strategies to reimplement some previous habits.
Mountains of literature have been written about changing habits, exercise, and fitness. Most of it is misinterpreted, not useful, and unproductive advice. I decided to look at the actual data and science of habits and productivity. After reviewing the studies and available literature a few strategies and studies stood out.
One of the enemies of new habits is requiring executive function and decision making to accomplish the goal. If every new habit or action you want to take requires executive function it is much harder to establish and maintain habits. There are two short phrases that essentially summarize all of this very neatly:
Don't make me think is a really nice phrase that can be generalized in the context as anything you can do to remove executive function from the process of performing an activity you want to start or keep performing. The studies and data back this up: environmental stability, cues, and removing decision making from an activity make it dramatically more likely to happen and be consistent. Example: If your gym clothes are laid out, the time and activity is set, and all you have to do is robotically put clothes on and go do the thing it is way easier to get started. Contrast with: Waking up, digging through an unsorted mess of clean clothes, wondering where you left your running shoes, having no planned activity for the workout, and having to make all of those decisions and do all of that work right there in the moment. The odds you derail at some point over the course of weeks increases dramatically.
Discipline equals freedom is the same theme. It may seem counterintuitive initially. It isn't just another meaningless "grind harder" mentality, though. It is about doing all of those little things consistently. Everything in your environment is rigorously maintained to support your main goals and habits, like consistently working out. If you have to drive to the gym, make sure it is always fueled up. Eliminate every decision you can that gets you to the point of starting and then finishing the workout. It is okay to have to course correct, no plan will be perfect, but if you are, on average, doing the same thing at the same time in the same place and eliminating decisions so that it can all happen nearly automatically you have a far higher chance of succeeding at the long term goals. Let's dig into why these two ideas, as presented, are so powerful and supported by evidence.
Most fitness and habit change advice is garbage pop culture. So, I dug into research and tried to find the most validated and referenced strategies with scientific backing. Before we get to those, understand this: context stability is not a strategy -- it's a strong foundation to build on. Context stability means doing the same thing, in the same place, at the same time. It isn't a hard requirement, but if you are trying to ingrain a long term habit this is such a powerful tool I felt it deserved its own section ahead of the strategies. You can, of course, still build habits without context stability but the research is convincing that this lowers the friction consierably. Lally's research showed this is how habits actually form in the brain, environmental cues become triggers. So pick your time and place first, then layer these strategies on top:
The first three are pretty strongly validated. The A-Tier are useful and a little more situational.
The definitive study on habit formation was conducted by Lally et al. (2010) in their paper "How are habits formed: Modelling habit formation in the real world." [1]
Minimum habit formation time was 18 days for the most simple behaviors, such as consistently drinking water. Maximum time measured was 254 days for complex behaviors, such as exercise, which requires long-term discipline. The median time was 66 days for most moderate behaviors. This suggests that short term challenges are inadequate for establishing fitness behavior. This is not to say they are not valuable, but the mindset should aim towards the 100+ day range, since fitness and exercise is a long term complex behavior. Another interesting finding was that exercise habits took 1.5x longer to form than dietary habits. This suggests that if weight loss is a primary goal starting with dietary habits will be more effective in the short term.
One of the more encouraging findings is around consistency. Lally's data showed that missing a single opportunity did not affect the habit formation. The slope of automation increase resumed immediately after a single lapse. However, the data did point out a cumulative effect regarding inconsistency. One missed day is negligible, but it does add up.
Key Principle #1: Consistency is incredibly important, but it is not a rigid all or nothing property. Be flexible, but be aware of the cost of misses. Key Principle #2: Environment is one of the strongest predictors of behavior.
This section details the strategies for implementing new habits that have the most validation and study.
Implementation intentions is a concept developed by psychologist Peter Gollwitzer. The key concept is creating a specific plan in the format of: If situation X arises, then I will perform Y response. This strategy expands simple goal setting ("I want to exercise") by linking a specific situational cue to a specific response. The key power is that it offloads control from your internal motivation to the external environment. When 6:00 PM hits, you drive to the gym, no decision required. This mimics the neurological loop of a habit before the habit is fully formed.
The validation is absurdly strong. The seminal study published in the British Journal of Health Psychology compared three groups: a control group, a "motivation" group (who got educational material about exercise benefits), and an "implementation intention" group. The results were not subtle:
That's a 2.5x improvement over motivation alone. Meta-analyses show effect sizes around d=0.65 across populations, and the effect gets even stronger when you add mental imagery (visualizing yourself doing the action). [2]
How to use it: The "if" needs to be a stable, unambiguous cue, time or location work best. "If I have time" is too vague and will fail. "When I leave work at 5:30 PM, I will drive directly to the gym" is specific enough to trigger automatically. For me, with ADHD, this has been the single most effective tool. No decision fatigue, no activation energy problem, the cue triggers the action.
Self-monitoring means systematically tracking your behavior. It provides the feedback loop necessary for self-regulation, you can see if you're actually doing what you think you're doing. Systematic reviews identify self-monitoring as the behavioral change technique that explains the most variance in physical activity interventions. [3]
There's a critical distinction between active and passive monitoring:
The SMARTER trial found that higher adherence to self-monitoring was significantly associated with greater weight loss and activity maintenance. [4] Meta-analyses of mHealth interventions show apps increase physical activity by about 476 steps per day compared to controls. [5]
Key finding: Consistent monitoring beats detailed monitoring. Track something every day, even if it's just "did I work out: yes/no." Intermittent detailed tracking is far less effective than consistent simple tracking. The wearable on your wrist wins because it requires zero effort.
These strategies are effective and well-supported, but they work best for initiation or in specific contexts. They should augment the S-Tier strategies, not replace them.
WOOP is a cognitive strategy developed by Gabriele Oettingen that combines mental contrasting with implementation intentions. Here's the counterintuitive part: purely fantasizing about a positive future (imagine how great you'll look after losing weight!) can actually be demotivating. Oettingen's research found that positive fantasizing induces a physiological relaxation response, lower blood pressure, reduced arousal, that mimics having already achieved the goal. Your brain thinks the work is done, so it stops pushing you to act. [6]
WOOP fixes this by forcing you to contrast the positive future with the negative reality of present obstacles:
Interventions using WOOP have shown participants doubling their physical activity compared to controls. [7] It's rated slightly lower than pure implementation intentions only because it requires higher cognitive load, you have to do the mental work regularly. But for overcoming specific barriers, it's superior to simple planning.
Coined by behavioral economist Katherine Milkman, temptation bundling pairs an indulgence (a "want") with a virtuous behavior (a "should"). Classic example: only allowing yourself to listen to an addictive audiobook or podcast while at the gym. You leverage present bias, our tendency to overvalue immediate rewards, by attaching instant gratification to a delayed-reward activity. [8]
Milkman's RCTs showed temptation bundling can boost gym attendance by 10-51% in the short term. The problem? The effect decays post-intervention. If the audiobook loses its appeal, or if you break the rule and listen outside the gym, adherence to exercise often collapses. This makes it an excellent initiation tool to overcome initial inertia, but you need to transition to more intrinsic motivation for long-term maintenance.
Not all "groups" are created equal. The research distinguishes between "True Groups" (team building, shared goals, distinct identity) and "Standard Classes" (individuals exercising in the same room without interaction, just co-action). [9]
The active ingredient is social cohesion and the sense of belonging. In digital health, the concept of "supportive accountability" is critical, having a coach or dedicated workout partner creates a sense of liability to a trustworthy other, which significantly increases adherence. [10] The key word is "trustworthy": the relationship must be built on trust and benevolence, not judgment. A coach who checks in, encourages without shaming, and genuinely cares about your progress creates psychological accountability that automated reminders simply cannot replicate. You're less likely to skip when you know someone will notice and will be disappointed, not in you, but for you.
While "fake it 'til you make it" sounds cliche, there is robust academic backing for the role of self-identity in behavior maintenance. A meta-analysis by Rise et al. found that self-identity significantly predicts behavior even after accounting for intention and past behavior. [13] The core mechanism is cognitive consistency: we are psychologically driven to act in ways that align with how we perceive ourselves.
If you view yourself as "a runner," missing a run creates cognitive dissonance—a psychological discomfort that motivates you to get back on track to restore your self-image. Conversely, if you view yourself as "someone trying to run," missing a run just confirms your suspicion that you aren't one. The goal is to move from behavioral goals ("I want to run") to identity goals ("I am a runner"). This is often achieved by "small wins", proving the identity to yourself through small, undeniable repeated actions.
Willpower is a finite resource; environment is constant. "Choice Architecture," a concept popularized by Thaler and Sunstein, involves structuring your physical environment to make the desired behavior the path of least resistance. Research confirms that altering micro-environments can significantly change health behaviors without conscious deliberation. [14]
Examples of Cue Optimization:
By designing the environment, you remove the need for executive function. You aren't deciding to work out; you are simply following the cues you laid out for yourself.
Behavior change is not a "set it and forget it" linear process; it is a dynamic system requiring regulation. Control Theory, applied to psychology by Carver and Scheier, posits that self-regulation relies on a negative feedback loop: comparing a current state to a reference value (goal) and acting to reduce the discrepancy. [15]
Without a feedback loop, you are flying blind. If the loop is too slow (e.g., weighing yourself once a year), the error signal comes too late to correct the course effectively.
A number of other areas have been researched but they didn't have enough substance for me to go into detail on them. The S-Tier and A-Tier strategies are the only ones I found find in scientific literature that were properly built studies. Other strategies and ideas may work great for a particular person or group of people. They may work great in some specific context or for some specific principle. However, I wanted things that had general observability and broad understandable impact that "made sense" in terms of human behavior. I figured these would be the "gold standard" of habit and behavior change.
I tried to highlight the things that worked. However, this one stood out as an active strategy to avoid. I think the other strategies and behaviors are more than enough, so if the goal is long term habit formation, this just seems like an all around avoid.
Paying people to exercise is a staple of corporate wellness programs, and the data shows it works, temporarily. Systematic reviews confirm that financial incentives effectively increase gym attendance in the short term, up to about 6 months. [11] The problem is what happens when the money stops.
The reality is, once the incentive is removed, adherence typically drops back to baseline or lower. This is called the "crowding out" effect, explained by Self-Determination Theory (SDT). [12] Extrinsic rewards can actually destroy intrinsic motivation. When you learn to exercise for the money, you fail to internalize the value of the activity itself. The behavior becomes transactional, "I'll do this unpleasant thing for that reward", rather than part of your identity or something you find inherently valuable.
Once the transaction ends, so does the behavior. Worse, because the extrinsic reward trained you to view exercise as something worth doing only when compensated, you may now view it as even more aversive than before. The money confirmed that it's unpleasant work that requires payment.
Verdict: Financial incentives are validated for initiation, getting a completely sedentary person to take the first step. But they're a terrible long-term habit formation strategy unless they serve as a temporary bridge while you build more sustainable, internal motivation. Don't rely on them as your primary tool.
[1] Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998-1009. PMC Article
[2] Implementation Intentions and Physical Activity: A meta-analysis of effect sizes. James Clear
[3] Effective behavior change techniques to promote physical activity in adults with overweight or obesity. PMC Article
[4] Adherence to self‐monitoring and behavioral goals is associated with improved weight loss in an mHealth randomized‐controlled trial. ResearchGate
[5] Romeo, A., et al. (2019). Can Smartphone Apps Increase Physical Activity? Systematic Review and Meta-Analysis. JMIR Article
[6] Oettingen, G. WOOP Goal Setting: The Secrets Behind the Method and How to Apply It. Deel Blog
[7] WOOP: The Science-Backed Strategy for Turning Goals into Reality. Thriva
[8] Milkman, K. L., Minson, J. A., & Volpp, K. G. M. (2014). Teaching temptation bundling to boost exercise: A field experiment. PDF
[9] Burke, S. M., et al. (2006). Group versus Individual Approach? A Meta-Analysis of the Effectiveness of Interventions to Promote Physical Activity. ResearchGate
[10] Mohr, D. C., Cuijpers, P., & Lehman, K. (2011). Supportive Accountability: A Model for Providing Human Support to Enhance Adherence to eHealth Interventions. JMIR Article
[11] Barte, J. C. M., & Wendel-Vos, G. C. W. (2017). A Systematic Review of Financial Incentives for Physical Activity: The Effects on Physical Activity and Related Outcomes. Behavioral Medicine
[12] Financial incentives and the "crowding out" of intrinsic motivation in Self-Determination Theory. Radboud Repository
[13] Rise, J., Sheeran, P., & Hukkelberg, S. (2010). The Role of Self-Identity in the Theory of Planned Behavior: A Meta-Analysis. Journal of Applied Social Psychology, 40(5), 1085-1105. Wiley Online Library
[14] Marteau, T. M., Ogilvie, D., Roland, M., Suhrcke, M., & Kelly, M. P. (2011). Judging nudging: can nudging improve population health? BMJ, 342, d228. BMJ Article
[15] Carver, C. S., & Scheier, M. F. (1982). Control theory: A useful conceptual framework for personality–social, clinical, and health psychology. Psychological Bulletin, 92(1), 111–135. APA PsycNet