How Long Does It Take To Get A Flat Stomach (Science-Backed)

how long does it take to get a flat stomach

Losing stubborn belly fat is often one of the hardest and last areas to see improvement for many dieters. 

Losing belly fat and getting a flat stomach is done through achieving a caloric deficit by eating less, exercising more, and doing that for at least 6-12 weeks. The more stubborn your belly fat is, the more strict and consistent you need to be with your diet and exercises regimen throughout that period.

In previous articles we’ve talked about Simple Ways To Lose 5lbs and the Best 3 Day Workout Program To Lose Fat.

However, we have yet to discuss how to get a flatter stomach and the factors that may impact the rate at which you lose belly fat during a fat loss diet.

In this article we will review the science behind fat loss, specifically belly fat, and go over a few factors that may affect how long it will take to get a flat stomach:

  • What Is a Realistic Timeline to Get a Flat Stomach?
  • Male vs Female: Does This Matter?
  • Lifting vs Running: Does This Matter?
  • Old vs Young: Does This Matter?
  • 4 Mistakes to Avoid to Getting a Flat Stomach

Need a workout program? Try Fitbod for free.

What Is A Realistic Timeline To Get A Flat Stomach

what is a realistic timeline to get a flat stomach

Getting a flat stomach really depends on two main factors. 

  • Where you are starting from
  • What your definition of a “flat stomach” is

It is realistic to say that you can achieve a flatter stomach in as little as 6-12 weeks with a sound diet and exercise approach that places you in a slight and progressive caloric deficit for that time period.

Individuals who are starting out with more belly fat will need to spend a longer period of time getting rid of it than someone who has less fat to lose. The exact time it will take depends on many factors, which we will discuss below.

Additionally, everyone has a different definition of what they see as “flat stomach”. For the sake of this article, we will discuss how to get a “flatter” stomach than where you are starting from.

Related Article: Do Waist Trimmers Really Work? We Examine The Science

Male vs Female: Does This Matter?

While we do know that males tend to carry more adipose tissue (fat) around their midsection than females, the physiological mechanisms of losing belly fat (fat loss) are very similar between them. 

Research on belly fat loss in males vs females has not shown clear evidence to support the claim that one group is less likely to lose fat around the midsection, especially when both groups adhere to a workout program and diet that places them in a negative energy balance.

Related Article: Best 3 Day Workout Plan For Females (COMPLETE GUIDE)

Lifting vs Running: Does This Matter?

Getting a flat stomach is heavily dependent on losing weight, specifically fat. This comes from being in a caloric deficit through eating less and expending more energy.

When it comes to lifting vs running, there is no clear winner here in terms of which is best for a flat stomach. 

We do know that lifting during a cutting or fat loss phase provides immense benefits of muscle retention (not losing muscle when you diet), improving metabolism, and helping you burn more calories at rest.  However, in the end, it comes down to being in a calorie deficit.

For best results, it is recommended to lift, and throw in some running (if you choose), however, cardio is not a necessary aspect of fat loss programs when your diet is sound. Cardio can be a very useful tool for some individuals if they are already eating less and lifting weights.

Related Article: 3 Best Ab Workouts On Pull Up Bar (Complete List of Exercises)

Old vs Young: Does This Matter?

Losing fat as you age is often more challenging due to decreased muscle mass, decreased metabolism, and a more sedentary lifestyle (working long hours, not sleeping, poor eating habits, etc). 

One study, however, found that increased levels of subcutaneous fat increased with the degree of obesity, but was independent of age (1). While there are clear hormonal differences as you age, most individuals can still lose weight later in life, it will just take more effort and time. 

Reason being is that most increases in weight loss are directly related to poor food choices, lack of physical activity, sleep deprivation, stress, and a sedentary lifestyle. Over time, those all compound too, often resulting in decreased muscle mass and blunted metabolism.

For those reasons, losing fat and belly fat as you age can be more difficult, however most of the complications are in part due to controllable factors such as diet, physical activity levels, sleep, and stress management.

Need a workout program? Try Fitbod for Free.

4 Ways To Speed Up The Process Of Getting A Flat Stomach?

4 ways to speed up the process of getting a flat stomach

If you are having issues losing belly fat, the below four ways can help speed up your progress of getting the flat stomach you are after

Stick to Your Diet on the Weekends Too

This is the Achilles heel of most dieters. Friday through Sunday becomes a free for all, or in some cases even just a little more lax than the weekdays. While this may seem innocent, the fact is that not adhering to your diet on the weekends will 100% stand in the way of your success. 

Most people will often try to super compensate during the week by eating severely less or working out excessively, and while this may work for some, it is often not a sustainable way to live (and since it can take many weeks and months to lose belly fat, a long term approach is needed).

Instead of going off the deep end on the weekends, start treating weekends like any other day of the week when it comes to eating habits, schedules, and workouts. 

Is it more boring, this way?


But, I would rather get results than have fun on the weekends, be miserable during the week, and not get any results in the long run.

Related Article: How Much Weight Can You Lose in 60 Days (The Healthy Way)

Stop Drinking Alcohol

Alcohol is a waistline killer, and is more easily stored as fat in the body. When looking to get a flat stomach, alcohol consumption may be one of your biggest enemies (outside of simply eating too much and not working out).

Research has shown that both frequencies and drinking intensity were both positively associated with increased central (abdominal) apidpsity (fat) in both males and females. 

The strongest association (even more so than frequency) was with drinking intensity, which concluded that drinkers who participated in drinking many drinks at once (binge drinking) had the strongest correlations with increased abdominal fat (2)

Workout 5+ Days a Week

If you are having trouble reaching your goals and losing the last few points, there is a strong chance that you need to do a little more work to get over the hump. This often means figuring out a way to burn a few more calories or eat a little less so that you can stay in a caloric deficit for a few more weeks.

If you are not working out five days a week, and are already being perfect on your diet, then you need to increase your energy output. This can come by way of increasing your step count (see below) or adding in another workout (or however many you need to train five days). 

To be clear, you do not need to lift five days to lose weight, however if you are struggling to lose weight and are currently eating healthy, lifting only 2-3 days a week, and have a semi-active daily lifestyle, increasing your workouts to five days a week may give you the little boost you need.

Looking for the perfect workout program to help you lose the last few pounds? 

Try using the Fitbod App, which will design a workout program based on your goals, schedule, and gym equipment to help you take your fitness to the next level. With over 600 movements and exercises videos, you can be sure to perform the movements correctly for optimal results. Take the guesswork out of your workouts. 

Try Fitbod for free.

Related Article: Core Workouts At Home: 21 Exercises You Can Do In 20-Min

Increase Your Step Count to 8,000+ Per Day

Numerous studies have concluded that increasing your step count to at least 8,000 steps per day can have a significant impact on BMI and overall health (3). 

Furthermore, some studies have concluded that a daily lifestyle that includes 8,000+ steps per day was more beneficial than an inactive lifestyle that included 30 minutes of cardio. 

Bottom line, if you want to decrease BMI and waist circumference, increase your step count and daily activities outside the gym in addition to following a diet and workout plan.

Related Article: How Much Weight Can You Lose in 60 Days (The Healthy Way)

4 Mistakes To Avoid To Getting A Flat Stomach

4 mistakes to avoid to getting a flat stomach

Below are four common mistakes people make when looking to get a flat stomach. 

Most of the time, these occur after a few hard weeks of sticking to the diet, or towards the end of a diet program when people are nearly there, and begin to cut themselves some slack. 

Rewarding Yourself with a Cheat Meal or Treat After a Tough Workout

Rewarding yourself with a meal that is outside your pre-determined macros for that post workout meal is a great way to derail your chances of getting a flat stomach. 

Getting a flat stomach, especially for those who truly struggle to achieve one, comes down to sticking to your diet, EVEN when you think you can cut yourself some slack. 

Reward yourself with a pat on the back and a sense of accomplishment knowing you are working towards a serious goal, rather than temporarily derail or delay the timeline by not following your diet.

Related Article: How Long Does It Take To Get Abs + Tips To Make It Quicker

Letting One Bad Meal Dictate The Rest of the Day

If you have a meal that is over your allotted calorie and macro limit, be sure to get right back on schedule, even if that means eating a few hours later. 

The last thing you want to do is start skipping meals to make up for it, or to tell yourself that you’ll start tomorrow since it’s easier to do that mentally than to stop yourself in the act. 

One bad meal out of 35 (5 meals a day x 7 days a week) won’t make a huge difference, however, when one bad meal turns into a bad day of eating (5 out of 35 meals), that can be the difference between having a flat stomach or not. 

Related Article: Ab Day At The Gym: How To Do It Properly + Sample Program

Thinking Sit Ups and Crunches Burn Belly Fat

Believe it or not, research shows that 6-weeks of direct abdominal exercises had no effect on abdominal fat loss (4). 

While it did increase muscle endurance, the study shows that without being in a caloric deficit, you will not lose belly fat, no matter how many sit ups you do. 

If you are looking to get a flat stomach, you need to prioritize your diet, and not think that you can do more situps or exercise to counteract poor diet adherence and planning.

Related Article: 15 Types of Crunches (How To Do Them + Pros & Cons)

Demonizing Carbs

When looking to lose belly fat, many people want to start demonizing carbs, sourcing them as the reason they are holding onto belly fat.

Research has shown however, that there are no clear and significant advantages to nutrient quality or source when it comes to fat loss and belly fat loss, but rather that the sole significant factor is caloric restriction (5). 

While there are many other benefits of eating healthier sources of fat, carbohydrates, and protein, it should be noted that over consuming calories from “healthy foods” will not result in weight loss.

Getting Discouraged Despite Progress Everywhere Else

If you are reading this article, there is a strong chance losing belly fat is the most challenging spot for you on your body. 

This can be frustrating, which is exactly why so many people quit near the end of their diet, or loosen up their discipline. Losing the last few inches or pounds in a diet is often the hardest (think about climbing a mountain ‒ the last little bit is often the most treacherous to climb). 

Most people drop off at the end of diets because they get discouraged at how much harder it is to lose weight than in the earlier stages. 

If you accept the fact that diet progress is not linear, but rather it is exponentially harder and harder the deeper you go into a diet, you will be able to wrap your mind around the challenge and be more likely to push through to the end.

Looking for a workout program? Try using the Fitbod App, which will design your program based on your logged training data and goals. The workouts will adapt automatically to your levels of recovery and rate of progress. With over 600 movements and exercises videos, you can be sure to perform the movements correctly for optimal results. Take the guesswork out of your workouts. Try Fitbod for free.

Frequently Asked Questions:

Which core exercises burns the most belly fat?

While core exercises alone won’t burn belly fat, they can help strengthen and tone the underlying muscles, improving overall abdominal appearance as fat is reduced through other methods.

Here are the top 10 most effective ab exercises according to Fitbod to help support reducing visceral fat

1. Crunches (Video)
  • Muscle Targeting: Focuses on the rectus abdominis, the primary muscle responsible for six-pack abs.
  • Beginner-Friendly: Simple movement that can be easily modified for increased difficulty.
2. Sit Ups (Video)
  • Full Range of Motion: Engages the entire core by lifting the upper body completely off the ground.
  • Strength Building: Enhances core strength, contributing to overall stability and posture.
3. Plank (Video)
  • Static Hold: Builds endurance and strength in the core, shoulders, and back.
  • Versatile: Can be modified with variations like side planks to target different muscle groups.
4. Dead Bug (Video)
  • Stability: Improves coordination and stability by engaging the core to stabilize the moving limbs.
  • Low Impact: Gentle on the back, making it ideal for beginners and those with lower back issues.
5. Leg Pull-In (Video)
  • Lower Abs Focus: Targets the lower abdominal muscles, which are often harder to engage.
  • Dynamic Movement: Combines flexibility and strength, enhancing overall core stability.
6. Bicycle Crunch (Video)
  • Combined Engagement: Targets both the upper and lower abs as well as the obliques.
  • Increased Activation: Keeps the core constantly engaged, promoting muscle endurance.
7. Scissor Kick (Video)
  • Continuous Tension: Maintains constant tension on the abs, promoting muscle endurance.
  • Lower Abs Focus: Primarily targets the lower abdominal muscles.
8. Reverse Crunch (Video)
  • Lower Abdominals: Focuses on lifting the hips, targeting the lower abs effectively.
  • Reduced Strain: Less strain on the neck and upper back compared to traditional crunches.
9. Russian Twist (Video)
  • Obliques: Targets the obliques, improving rotational strength and core stability.
  • Versatility: Can be performed with or without weights to adjust the intensity.
10. Flutter Kicks (Video)
  • Cardio Element: Adds a cardio component to core training, increasing calorie burn.
  • Lower Abs: Effective for engaging and strengthening the lower abdominal muscles.

How Long Does It Take To Get A Flat Stomach By Doing Sit-Ups

Research has shown that without caloric restriction, doing sit ups will not decrease abdominal fat loss. To get a flatter stomach, you need to lose body fat, which can take 6-12 weeks depending on how much fat you need to lose.

How Long Does It Take To Get A Flat Stomach By Walking

As discussed above, getting a flat stomach is 100% depending on being in a caloric deficit for 6-12 weeks, through eating less and burning more calories.

About The Author

Mike Dewar

Mike holds a Master’s in Exercise Physiology and a Bachelor’s in Exercise Science. He’s a Certified Strength and Conditioning Specialist (CSCS), USA Weightlifting Advanced Coach, and has over 10+ years of experience working with collegiate athletes, national level lifters, and beginners alike. Mike is Founder of J2FIT Strength and Conditioning, a growing global training company with gyms in New York City, Cincinnati, and online offering personal training, online custom coaching programs.


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