If you're ready for a challenge that will blast away belly fat, our 21-Day Flat-Belly Challenge is for you. Each day, we have an effective workout paired with a clean-eating recipe, along with bonus tips to help you whittle your waist even more. First, check out our shopping lists for each week below, then keep reading for descriptions of each day's challenge. We've compiled everything you need here so you can start anytime you want. Click on the link at the bottom of each day to get the specific workout and recipe, or use this calendar  to click through to each challenge. Prepare to feel slimmer, stronger, and more confident in just three weeks!
Week 1 Shopping List 
Week 2 Shopping List 
Week 3 Shopping List 
— Additional reporting by Michele Foley, Lizzie Fuhr, Aemilia Madden, Susi May, and Jenny Sugar
Workout: Let's begin with the fat-blasting workout. We've created three versions of this treadmill run, along with a printable version of all three levels. If you're new to running, try the Walk/Run plan further down the page. And if you want to increase the speed, use the Run Faster program.
Recipe: As part of your healthy breakfast or lunch, whip up a deliciously sweet flat-belly smoothie. It's packed with ingredients that fight belly fat and reduce bloating such as blueberries, pineapple, kale, and Greek yogurt — all for under 300 calories.
Bonus: Get a head start on Day 2 by whipping up this overnight oats  recipe to enjoy tomorrow morning.
Get all the details for Day 1 here .
Workout: Plank is one of the most effective exercises to target your core and upper body. Here's a 20-minute circuit workout combining six different dynamic variations of the basic plank — remember to stretch your back and arms for a couple of minutes after you've completed all those planks.
Recipe: Last night you prepped this whole-grain recipe, so it's time to meet the easiest belly-bloat-fighting breakfast of all time: overnight oats. It doesn't get any better than mixing a few ingredients together before bed and grabbing a spoon when you're ready to eat a delicious breakfast.
Get the details for Day 2 here .
Workouts: If you want to achieve that flat belly, cardio intervals should be a regular part of your fitness routine. Short, intense bursts have been proven to melt away fat, especially around your midsection. This 30-minute treadmill workout is a favorite of celebs like Sandra Bullock  and Kim Kardashian , and once you hop on the machine it'll be easy to see why.
Recipes: After your sweat session, fuel up with a substantial quinoa and kale salad with many different belly-busting properties. Quinoa is full of protein to help keep you full, while the fiber in kale will also help aid in slow digestion. Moreover, studies have shown that blueberries and almonds may both help diminish belly fat. At under 400 calories, this colorful and flavorful salad is hard to beat.
Bonus: Start your day with this caffeine-free cranberry and apple cider vinegar shot. A favorite of actress Nikki Reed , this detox drink masks the flavor of digestion-friendly, liver-cleansing apple cider vinegar with pure cranberry juice. The result? A boost of energy whenever you need it.
Get the details for Day 3 here .
Workouts: Today's ab workout does double-duty in the flat-belly department: not only does it target your core to help define ab muscles, but it also builds muscles all over your body, which helps rev up your metabolism to burn more calories throughout the day.
Recipe: Don't be put off by the "salad" description; this warm, wilted cabbage and quinoa dish makes a light, comforting dinner that soothes tummy issues. Each ingredient helps digestion, and the fiber in the chickpeas, cabbage, and quinoa will help you debloat. If you'd like, add a dollop of Greek yogurt for a creamy element and a dose of belly-helping probiotics.
Get the details for Day 4 here .
Workout: You've completed four days of intense workouts that have kept your heart rate up and muscles burning. Today it's time to pull back a bit and allow your body the rest it needs to recharge itself for tomorrow's workout. As any trainer will tell you, a rest day is just as important as a workout.
Don't forget, though, that a day of rest doesn't always have to equal inactivity. Opt for some light cardio like a walk around the neighborhood, which will help get the blood flowing to tired muscles. If that doesn't appeal to you, give your body the stretch it needs by flowing through a restorative yoga sequence or just enjoy a relaxing night in.
Recipe: Is it happy hour yet? Our pineapple mojito can be made sans alcohol, but regardless of whether you leave the rum in or out, the cold-pressed juice contains pineapple and mint, which are both known for their detoxing and debloating benefits.
Get the details for Day 5 here .
Workouts: Today's workout is 30 minutes of steady-state cardio followed by some serious ab work. Pick your favorite cardio — running, cycling, swimming, dancing — and keep moving at a steady pace for 30 minutes. Then strengthen your core and tone your abs with this 10-minute ab video.
Recipes: Made with a handful of ingredients you probably already have in your kitchen, today's healthy treat is a cinch to whip up. The berries, almonds, and yogurt in this low-calorie dessert help fight belly fat with every bite.
Get the details for Day 6 here .
Workout: If your body could use some fine-tuning, hop on your yoga mat and do today's eight poses designed to detox the body. You have your circulatory, digestive, and lymphatic systems to thank for getting rid of toxins and waste, and these poses stimulate those systems. Pick out the poses your body needs or practice them all, and you'll be on your way to feeling like a new you.
Recipe: Since wheat can cause bloating for many, make our low-carb, Paleo-friendly noodles made from zucchini instead. Lightly cooked until tender and flavored with garlic and red pepper flakes, this grain-free pasta alternative is perfectly filling, but won't leave you feeling stuffed.
Get the details for Day 7 here .
Workout: It's time to step up your fat-blasting running workout with intervals! Get ready to burn some mega calories with a longer 45-minute treadmill workout. Set the incline to one percent to prevent shin splints, and as with all our workouts, feel free to increase or decrease speed, depending on your level of fitness.
Recipe: Give yourself an energizing reboot while also debloating the belly with a vegan avocado smoothie. Made with fiber-rich avocado to keep things moving along, it's also made with hydrating aloe vera juice and coconut water, as well as toxin-flushing lemon juice to help keep your digestive system feeling happy.
Bonus: Get ready for Day 9: here's another overnight recipe that takes just a few minutes to prep and is a delicious way to start your morning — chia seed pudding .
Get the details for Day 8 here .
Workout: Doing the basics of Capoeira, a Brazilian dance-like martial art, will work your belly, legs, arms, and back from every angle. Our 30-minute video workout is both challenging and fun, and trainer Brett Hoebel provides modifications for every level. Once you press play, get ready to sweat and burn some serious calories!
Recipe: Chia seeds and coconut milk marry for a Paleo-friendly pudding that works great for breakfast. High in anti-inflammatory omega-3s, this sweet chia pudding is a make-ahead recipe that will save you time, fill you up on fiber, and help you debloat. This flat-belly breakfast is full of good-for-you ingredients, but the flavor will make it feel like dessert! Top off your jar with fresh pineapple or your favorite Summer berries for even more flat-belly power.
Get the details for Day 9 here .
Workout: If you're short on time today, this 30-minute elliptical workout is just for you. It gets you in and out of the gym fast, while burning a substantial amount of calories to boot. And since intervals blast belly fat, this is a great midweek workout to do, especially if you're bored of the treadmill or need to fit in a workout at lunch.
Recipe: For a quick detoxifying meal, this crunchy cabbage and hemp salad does what you need, deliciously. It's chock full of fiber to help regulate bloating and digestion, and it's easy to throw together on a busy weekday.
Bonus: Feeling a bit sluggish? Whip up a chia, supergreens, and coconut water superfoods shot, which is full of fiber and is perfect for a morning boost. Celebrity trainer Valerie Waters recommends her clients chug this drink before a morning workout for an extra energy boost.
Get the details for Day 10 here .
Workout: Combine cardio with core work to reap the flat-belly benefits of both types of sweat sessions. This workout alternates between jumping rope and standing ab moves, so you can tone your belly while burning serious calories in just 20 minutes.
Recipe: Think of our Summer quinoa salad as a bulked-up tabbouleh, since detoxifying parsley lays the base of the greens, while a scoop of quinoa and diced avocado provide over 60 percent of your daily recommended fiber — a must-have nutrient if you're looking to support healthy digestion and your flat-belly goals.
Get the details for Day 11 here .
Workout: Today's workout isn't a workout at all! First up: some well-deserved time away from the gym. While a rest day doesn't have to equal just sitting on the couch, it's important to allow your body time to repair itself — that's how strong, calorie-burning muscles are made. So today, take a time-out with a low-intensity workout like a walk or restorative yoga. Or, just enjoy a relaxing night in. And why not enjoy a fresh, tasty mocktail while you're at it? You've earned it!
Recipe: Using hydrating honeydew melon for our green juice mocktail gives it a bright, fun hue. A little bit of ginger adds a slight spiciness that also aids with digestion. The recipe serves four, so invite your friends over for a healthy happy hour while you enjoy your rest day.
Get the details for Day 12 here .
Workout: Today's workout is 30 minutes of steady-state cardio followed by some serious ab work. Pick your favorite cardio — running, cycling, swimming, dancing — and keep moving at a steady pace for 30 minutes. Then strengthen your core and tone your abs with a 10-minute video featuring surprising variations of sit-ups and planks.
Recipe: Celebrate Summer and satisfy your sweet tooth with this grain-free crumble featuring blueberries, which studies indicate may fight belly fat. This dessert also features almonds; high in MUFAs (monounsaturated fats), almonds help burn away the fat that collects around your middle.
Get the details for Day 13 here .
Workout: Skip the crunches and hop on your mat for our effective yoga workout designed to target the abs. Begin with a few Sun Salutations to warm up, and then move through this 14-pose sequence on the right side, and repeat on the left. Keep in mind that solely doing core-strengthening moves like these isn't the key to a flatter stomach, but it is part of the equation. Toned abs will look slimmer once you do lose overall body fat from doing cardio, and having more muscle mass increases your calorie burn.
Recipe: With just a few ingredients including red peppers, ground turkey, and tomatoes, in less than 30 minutes, you can create a fresh, clean meal with more than 30 grams of protein! A meal high in protein will satiate your hunger, so you stay satisfied without the urge to reach for a high-calorie late-night treat. This Italian Paleo-friendly recipe is low in carbs and is just 285 calories. Enjoy with our flat-belly salad.
Get the details for Day 14 here .
Workout: For a quick workout that torches calories, tackle today's 30-minute treadmill interval workout. This boredom-busting workout will burn belly fat and leave you feeling energized for the week ahead.
Recipe: If you've been feeling tired and in need of a body boost, prepare our delicious and debloating papaya ginger mint smoothie. With stomach-calming ginger and mint, plus the probiotics in Greek yogurt, it will help relieve digestion and flush out toxins, leaving you feeling refreshed. If you've enjoyed an indulgent weekend, this smoothie is a perfect way to wind down.
Get the details for Day 15 here .
Workout: Today's workout is all about Tabata. Tabata is high-intensity training that's fun, blasts calories, and moves so quickly that it's hard to get bored. For this type of interval workout, you perform an exercise at maximum intensity for 20 seconds, followed by 10 seconds of rest. You repeat this on-off pattern a total of eight times, making one complete Tabata round four minutes.
Recipe: Full of whole-grain fiber, a hearty bowl of oatmeal will fill you up and keep you satisfied all morning, which means no need to snack on high-calorie treats before lunch. Buying plain oats is healthier and less expensive than buying presweetened flavored packets, but making your own doesn't mean you have to go without flavor. Add fruit, nuts, nut butter, flax or chia seeds, pureed frozen fruit, and yogurt to increase the belly-filling fiber and protein without adding a ton of extra calories.
Get the details for Day 16 here .
Workout: Today's challenge is a belly-blasting cardio workout — intervals on the treadmill. It's an excellent way to target midsection fat.
Recipe: Relieve digestion woes and help shrink your belly with a tropical pineapple arugula salad. Pineapple contains enzymes that help you debloat and ease digestion, while avocado contains fiber and MUFAs (monounsaturated fatty acids) to fight belly fat. Plus, this salad is bursting with fresh flavor, so all your taste buds will be satisfied.
Bonus: Looking for an extra flat-belly boost today? Add a few detoxing and debloating ingredients to your water. Squeeze some lemon, grate some ginger, and slice some cucumber into your water for added flavor and nutrients. You might even find yourself drinking more — a great strategy for flushing out your system and making you feel less puffy.
Get the details for Day 17 here .
Workouts: Who needs a gym? With this bodyweight workout, you can tone your entire body anywhere. Our no-equipment workout will get your heart rate up while building metabolism-boosting muscle and whittling your middle. Just print this poster, and get your sweat on anytime you want!
Recipe: After a tough strength-training session like this bodyweight workout, protein is necessary to help your body recover. And that protein-packed meal needs to come together quickly, before your hunger overwhelms you. This delicious panko-crusted fish dinner takes less than 20 minutes from prep to plate, but the best part is one serving offers more than 36 grams of protein, which can help the body burn more fat!
Get the details for Day 18 here .
Workout: Today it's time to pull back a bit and allow your body the rest it needs to recharge itself. A rest day is just as important as a workout, and you deserve some time away from the gym.
With that said, it's important to remember that a day of rest doesn't always have to equal inactivity. Opt for some light cardio like a walk around the neighborhood, which will help get the blood flowing to tired muscles. If that doesn't appeal to you, give your body the stretch it needs by flowing through a restorative yoga sequence or just enjoy a relaxing night in.
Recipe: Relax with a cocktail! For anyone craving a fruity cocktail minus the calories, our variation of a classic tequila bramble makes a great choice. The recipe doesn't contain any store-bought mixers or fruit juice but relies on fresh, seasonal belly-fat-blasting blackberries and a hint of agave syrup for its sweetness. If you want to enjoy your cocktail alcohol-free, you can omit the tequila and substitute the blackberry liqueur with a splash of berry juice concentrate.
Get the details for Day 19 here .
Workout: Today's workout is 30 minutes of steady-state cardio followed by some serious ab work. Pick your favorite cardio — running, cycling, swimming, dancing — and keep moving at a steady pace for 30 minutes. Then tone and tighten your midsection with a 10-minute ab video. No need for weights, so no excuses!
Recipe: You've made it 20 days in, so it's time for a treat! Enjoy a vegan chocolate pudding that tastes decadent but is full of healthy belly-flattening fats thanks to one surprising ingredient. It's a fast and easy treat you can whip up any time and save for later.
Get the details for Day 20 here .
Workout: Today's yoga sequence is all about burning your own internal fire through fierce twists and loads of vinyasas. The 11 twisting poses will get all your muscles working — it's the perfect sequence to get things moving.
Recipe: Eating fish can promote weight loss since lean protein fills you up and sustains your energy, which prevents you from oversnacking later. Plus it's a great source of omega-3 fatty acids, which we all could use. If you've never made fish, today's recipe is an incredibly easy one that's low in calories (160!) and only requires four ingredients. Serve alongside our flat-belly salad for a light, filling dinner.
Get the details for Day 21 here .