Ready, reset, go: our Flat-Belly Challenge  has 21 days of belly-blasting workouts, tips, and recipes to help you start a new season on a fresh note. Day 3's challenge is a cardio belly buster followed by a filling superfood quinoa salad and a secret bonus boost. Read on for the plan!Image Source: POPSUGAR Photography / Kat Borchart 
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. While it's only half an hour, this workout is challenging, so you'll burn major calories in just a few minutes.
Feel free to adjust the speed and incline depending on your running level. Print out the workout here .
|6:30-7:30||5.0||0.0||Begin Incline Run Section|
|11:30-12:30||3.0||0.0||End Incline Run Section|
|12:30-13:30||3.0-4.0||0.0||Begin Sprints and Walks Section|
|17:00-18:00||3.0||0.0||End Sprints and Walks Section|
|18:00-19:00||6.0||0.0||Begin Endurance Section|
|23:00-24:00||3.0||0.0||End Endurance Section|
|24:00-24:30||6.0||0.0||Start Flat and Hills Section|
|28:30-29:00||3.0||0.0||End Flat and Hills Section|
Superfood SaladImage Source: POPSUGAR Photography / Leta Shy
After your sweat session, fuel up with a substantial 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.
Get the recipe for this kale, quinoa, and blueberry superfood salad here .
Bonus Boost: Cranberry Apple Cider Vinegar ElixirImage Source: POPSUGAR Photography / Leta Shy
Need an extra boost on this hump day? 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.