Forget starting over every Monday. Here's what research tells us about building healthy habits that can actually fit into your life.
Can we talk about how exhausting it is to constantly feel like you're starting over?
You decide you're finally going to get in shape. You buy the workout clothes, save a bunch of healthy recipes, and promise yourself that this time will be different.
And for the first week? You're doing amazing.
Then the kids get sick. Work gets crazy. You miss a workout. Your water bottle disappears somewhere in the car.
And suddenly you're telling yourself you'll start again next Monday.
But what if the problem isn't that you aren't motivated enough?
What if the problem is that you've been trying to change too much, too quickly, without creating a routine that makes those changes easier to maintain?
That's what we're exploring in our Fittest for Fall 90-day challenge.
Instead of giving you another list of things to do to lose weight, we're looking at something that could be much more useful: the science of how habits form.
Because getting healthier shouldn't require waking up every morning and convincing yourself to become a completely different person.
Let's talk about five research-backed strategies that can help you make exercise, hydration, and healthier decisions a more natural part of your everyday life.
1. Your Brain Likes Repetition More Than Motivation
Here's something fascinating.
Researchers at University College London studied how people developed everyday habits over 12 weeks.
Participants chose a simple behavior, like drinking water or going for a walk, and repeated it in the same situation each day.
The researchers found that the time it took for a behavior to approach automaticity varied dramatically, ranging from 18 to 254 days among the participants whose data could be modeled.
That means the popular idea that it takes exactly 21 days to form a habit? It's not supported by this research.
Some habits become easier relatively quickly. Others take months.
And that's actually good news.
Because if you're three weeks into your fitness routine and it still feels like work, it doesn't mean you're failing.
It means you're still practicing.
Try this: Give your new habit a permanent place in your day.
Instead of telling yourself:
"I'm going to start walking more."
Try:
"After I drop the kids off at school, I'm walking around the neighborhood for 10 minutes."
Or:
"After I make my morning coffee, I'm filling my water bottle."
The difference is that you're no longer waiting for motivation to appear. You're giving your brain a consistent reminder of what comes next.
This is one of the ideas behind habit stacking, popularized by James Clear in his book Atomic Habits.
You're attaching something new to something you already do.
Your Fittest for Fall assignment: Choose one habit you want to build and attach it to an activity that's already part of your daily routine.
Research: Lally et al., 2010, European Journal of Social Psychology.
2. Stop Making Your Fitness Goals So Big That You Avoid Starting
Have you ever planned a 45-minute workout and then skipped it because you only had 15 minutes?
It's funny how our brains do that.
We convince ourselves that if we can't do the whole thing, there's no point in doing anything.
But that's exactly the kind of thinking we're trying to change.
In Atomic Habits, James Clear introduces the Two-Minute Rule: make the starting version of a new habit so easy that it takes less than two minutes.
That doesn't mean two minutes of exercise will give you the same physical results as a complete workout.
It means you're making it easier to begin.
And beginning is often the hardest part.
Try this: Create a minimum version of your routine.
Let's say your goal is to start strength training.
Your ideal workout might be 30 minutes.
But your minimum version could be putting on your workout clothes and completing one set of squats.
That's it.
On a good day, you'll probably do more.
On a busy day, you still have an opportunity to practice the routine.
Here's how that could look with different habits:
Walking: Start with five minutes around the block.
Strength training: Complete one set of a beginner-friendly exercise.
Hydration: Fill your water bottle before drinking your morning coffee.
Nutrition: Add a protein source to your usual breakfast.
Small actions aren't meant to replace meaningful physical activity. They're the starting point that helps you build toward it.
And as your routine becomes more comfortable, you can gradually increase your activity.
Your Fittest for Fall assignment: Pick one healthy habit and create a version so simple that you can do it even on a busy day.
3. Research Suggests That Having a Specific Plan Can Help You Exercise More Consistently
Let's talk about the difference between wanting to exercise and actually exercising.
Because those are two very different things.
You can genuinely want to get healthier and still struggle to follow through.
Researchers call one strategy for closing that gap an implementation intention.
It sounds complicated, but it's actually pretty simple.
You decide ahead of time when, where, and how you're going to perform a behavior.
A 2018 systematic review and meta-analysis examined randomized trials of this strategy and found that implementation-intention planning, particularly when reinforced over time, could help people increase their physical activity.
In other words, planning the details can be more useful than simply making a promise to yourself.
Try this: Make an actual appointment with your workout.
Instead of:
"I'm going to work out three times this week."
Try:
"Monday and Thursday at 9 a.m., I'm doing a 20-minute strength workout in my living room."
And here's something else worth doing.
Make a backup plan.
"If I can't exercise in the morning, I'll take a 10-minute walk after dinner."
This is especially helpful for women who are juggling work, kids, school schedules, and about a hundred other responsibilities.
Your routine needs to work with your life, not against it.
Need easy workout ideas?
We share and repost workout ideas from content creators who make exercise feel approachable, whether you're working out at home or heading to the gym.
You don't need to know how to create an entire fitness program yourself to start moving.
Your Fittest for Fall assignment: Schedule two strength-training sessions this week and choose a backup option for days when your original plan falls apart.
Research: Silva et al., 2018, PLOS ONE.
4. Tracking Your Habits Can Help You Follow Through
Now, this is where things get really interesting.
A 2016 meta-analysis published in Psychological Bulletin examined 138 studies involving nearly 20,000 participants.
Researchers found that interventions encouraging people to monitor their progress improved their chances of reaching their goals.
The effects were particularly strong when people physically recorded their progress or reported it to someone else.
Think about that for a second.
Something as simple as writing down what you're doing can help you become more consistent.
And no, we're not talking about obsessively tracking every calorie or weighing yourself every morning.
We're talking about creating a visible record of your effort.
Try this: Track the actions, not just the results.
During Fittest for Fall, try tracking:
The days you went for a walk.
The strength workouts you completed.
Whether you practiced your water-drinking routine.
The meals where you made a choice that supported your goals.
How your energy, strength, and endurance are changing.
We've created a downloadable Fittest for Fall PDF on our website to help you stay organized throughout the challenge.
Use it as a place to record your progress and check in with yourself.
And remember, the goal isn't to fill every box perfectly.
It's to understand your own patterns.
Maybe you discover that you're great at working out on Mondays but struggle on Fridays.
Maybe you realize that when you fill your water bottle in the morning, you're much more likely to drink it throughout the day.
That's useful information!
You're learning how to build a routine around the person you actually are.
Your Fittest for Fall assignment: Download our Fittest for Fall PDF and start recording the small actions you're taking toward your goals.
Research: Harkin et al., 2016, Psychological Bulletin.
5. Missing One Day Doesn't Mean You've Ruined Your Progress
Okay, this might be my favorite part of the research.
Remember that habit-formation study from University College London?
Researchers also found that missing one opportunity to perform a habit didn't materially disrupt the overall habit-formation process.
Read that again.
One missed day doesn't erase the work you've already done.
And yet, how many times have we treated one missed workout like the entire week was ruined?
We miss Monday, so we decide to restart next week.
We eat something that wasn't part of our plan, so we figure we might as well eat whatever we want for the rest of the day.
We fall behind on our goals, so we give up entirely.
But building a healthy lifestyle requires something more important than perfection.
It requires learning how to return to your routine.
Try this: Create a restart plan before you need one.
Think about what normally throws you off.
Is it a busy workweek? School holidays? Traveling? Getting sick?
Now decide what you'll do when that happens.
For example:
"If I miss my workout, I'll do my next planned session instead of trying to make up everything I missed."
Or:
"If I have a week where I'm not eating as balanced as I'd like, I'll start with one nourishing meal rather than attempting another restrictive diet."
You don't need to punish yourself for having a busy life.
You need a routine that allows you to be human.
Your Fittest for Fall assignment: Write down the three things most likely to interrupt your fitness routine and create a simple plan for how you'll get back on track.
How to Put These Habits Together Over 90 Days
Now that you understand some of the science, let's turn it into something you can actually use.
We're breaking Fittest for Fall into three stages.
Days 1–30: Make It Easy
This first month is about creating consistency.
Start with a short walk attached to something you already do. Fill your water bottle at the same time every morning. Schedule two beginner-friendly strength workouts per week.
Don't worry about doing everything perfectly.
Focus on making these actions easier to repeat.
Days 31–60: Build On What You've Started
Now that you've practiced showing up, begin challenging yourself a little more.
Increase your walking time or pace.
Gradually add repetitions or resistance to your strength workouts.
Start paying closer attention to how you're building your meals, especially including enough protein and a variety of nutritious foods.
Keep tracking your habits and adjusting your schedule as needed.
Days 61–90: Learn How to Keep Going
This is where we want you to think beyond the challenge.
Ask yourself:
Which habits are becoming easier?
Which ones still require effort?
What routines have worked best with my schedule?
What will I do when life gets busy again?
Because 90 days isn't a magic deadline for habit formation.
It's an opportunity to spend three months practicing skills that can help you for years.
The Real Goal of Fittest for Fall Isn't Just Getting in Shape
Here's what I hope you take away from all of this.
At some point, you're probably going to find yourself in another winter season.
And I don't necessarily mean the weather.
I mean those seasons of life when you're overwhelmed, exhausted, busy, or simply not prioritizing yourself the way you'd like.
We all experience them.
But imagine going into your next winter season knowing exactly how to begin again.
You know how to make walking part of your day.
You know how to build a strength-training routine that works with your schedule.
You know how to make small, helpful decisions around food and hydration.
And most importantly, you know that missing a few days doesn't mean you've lost everything.
That's what we want you to gain from these 90 days.
Not another temporary transformation.
A framework you can come back to whenever you need it.
Because learning how to take care of yourself is something you'll use for the rest of your life.
And that's what Living LYVLI is all about.
Ready to Build Habits That Actually Stick?
Join us for Fittest for Fall!
Download our Fittest for Fall PDF from LYVLI, follow along with our easy workout inspiration on Instagram, and start with one small habit today.
You don't need to change your entire life overnight.
You just need to create a routine worth repeating.
Here's to getting stronger, building confidence, and learning how to Live LYVLI.
Research & References
We believe wellness information should be backed by more than trends. Here are the studies referenced throughout this article:
1. Lally, P., et al. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998–1009.
https://doi.org/10.1002/ejsp.674
2. Silva, M. A. V., et al. (2018). Impact of implementation intentions on physical activity practice in adults: A systematic review and meta-analysis of randomized clinical trials. PLOS ONE, 13(11), e0206294.
https://doi.org/10.1371/journal.pone.0206294
3. Harkin, B., et al. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2), 198–229.
https://doi.org/10.1037/bul0000025
Additional reading: James Clear, Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones(2018).
The research cited supports general habit-building and behavior-change principles. Individual results vary, and no particular 90-day routine guarantees weight loss or a specific fitness outcome.
