Now, it’s time to hop into the Women’s Health+ Ultimate HIIT Challenge. Step one: Sign up for your WH+ Premium membership for access to all the programming outlined below. (Your purchase also unlocks our full library of WH Challenges and Guides.)

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This comprehensive training plan takes the guesswork out of planning an entire week of workouts. The program includes HIIT workout days, active recovery days with optional steady-state cardio or yoga, and a group fitness day. Kasen designed this schedule to increase your overall fitness work capacity (meaning, how much exercise or physical activity you can do before experiencing fatigue), as well as ensure your body is properly rested and prepared for each exercise sesh. “It’s not how hard you can train; it’s how hard you can train and recover, so when you have your HIIT day, you can really ‘hit it,'” she says.

Here’s what’s in store for each session:

Lower Body Bodyweight Workout

Upper Body Dumbbell Workout

Total Body Dumbbell Workout

Upper Body Bodyweight Workout

Each 20-minute HIIT session combines fast-paced strength-training moves and low-impact cardio to get your heart rate up, build strength, and boost your metabolism. All of these workouts include follow-along videos of Kasen and her co-trainer, Gerren Liles, NASM, ACE, that show you exactly how to do each move with proper form, as well as offer modifications to increase or decrease intensity.

The HIIT workouts also require minimal equipment, either one set of dumbbells or just your bodyweight, making this workout plan extremely versatile. “You can do this in a small space or pretty much anywhere,” says Kasen. “If you have some weights at home, you can do it there. You can do it at a gym. You can do it on vacation [especially] if you’re short on time.”

On non-HIIT days, you’ll alternate between active recovery workouts, such as steady-state cardio or yoga, and a group fitness class you enjoy, such as a run club, aerobic exercise class, or Pilates class. (If you don’t want to partake in a group fitness class, you can always opt for steady-state cardio instead.)

For the steady-state cardio workouts, Kasen recommends brisk walking, light jogging, or cycling at a moderate pace for 30 minutes. The goal here is increase blood flow while still allowing your body to recover, so aim for “Zone 2” cardio, which is roughly 60 to 70 percent of your maximum heart rate. (A fitness tracker can help you measure this, but you can also estimate this by thinking about your “rate of perceived exertion” or RPE, which should be at 6 or 7 out of 10.)

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Follow This Schedule To Unlock Results

INSTRUCTIONS: Complete each of the four challenge workouts on the designated days, and then complete an active recovery/cardio workout or group fitness class on the other days. (Click on the links below and join WH+ to access the workouts.)

EQUIPMENT: 2 sets of dumbbells (1 medium, 1 heavy) and a yoga mat

TIME: Each challenge workout takes 20 minutes or less, and each active recovery cardio workout takes 30 minutes. The group fitness class and yoga workout may take longer, depending on your individual schedule and fitness goals.

The Benefits Of HIIT Workouts

HIIT workouts can boost your metabolic rate (helping you burn more calories throughout the day). And science backs up this short-and-sweaty approach: Thirty minutes of HIIT burns 25 to 30 percent more calories compared to other forms of steady-state exercise, according to one 2015 study.

Plus, if body recomposition is one of your health and fitness goals, HIIT can help fast track your results. Sedentary women who did a HIIT program changed their body composition in half the time compared to those who did a moderate-intensity exercise routine, per a study in the Journal of Diabetes Research.

But the health benefits don’t stop there. You’ll also improve cardiovascular health and endurance, movement efficiency, muscle strength and endurance, and even mental resilience, says Kasen. “The fast pace improves mental fortitude over a period of time.” Think about it: In HIIT workouts, you often tell yourself, “I can do anything for 20 seconds”—and then, you can. Soon enough, you’ll start applying that mindset to other areas in life.

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Why This HIIT Program Works For Every Exercise Level

Think a HIIT workout program is only for elite athletes who love doing endless burpees? Think again! These HIIT workouts hit different (sorry, had to). “Just because my program is high intensity doesn’t mean it’s high-impact,” says Kasen. “Everyone can do it.” Depending on your fitness level, you just may need to modify or advance certain exercises.

It helps if you’re a moderate exerciser with some experience doing strength and stability workouts, but even if you’re totally new to HIIT or working out in general, don’t worry, because Kasen’s got you covered. She and Liles offer multiple ways to decrease the intensity of each move, so you can challenge yourself without overdoing it or risking injury.

More on the advanced side of the spectrum? You can level up this workout program by going heavier with the dumbbell weight, Kasen says, or opting into the advanced versions of certain moves, like lifting your leg during a side plank. This workout challenge is totally customizable to your starting fitness level so you can maximize your gains.

Best part: You’ll continue to see results after you’ve completed the Ultimate HIIT Challenge. “This is a week-long program, but you’re going to see and feel a difference the following week,” Kasen says. “You’re going to be like, ‘Wow, my stress is decreased, my strength has gone up, my exercise capacity workload, all of that’s increased.'”

How To Use This Program To Get The Results You Want

These workouts can easily be incorporated into your regular exercise routine beyond this week-long challenge. To continue seeing results, you can extend this challenge to two weeks, Kasen says. After that, she recommends incorporating more strength workouts into your routine to balance out your training, and then you can circle back to this HIIT program.

You’ll also want to focus on proper nutrition throughout this week-long challenge, says Kasen. “Because you’re burning more calories, and your metabolism is working a lot quicker, you’re most likely going to have an increase in appetite.” Essentially, your body is telling you that it needs more fuel to function normally, and one way to meet those additional needs is by increasing your protein intake from quality sources. “Just be mindful of your food choices throughout the day, so they help you recover and you’re able to jump into your next session feeling great,” says Kasen.

On that note, adequate sleep is also key to proper recovery during the Ultimate HIIT Challenge. “This is going to be demanding and stressful on the body, so you need to make sure that you’re rested so you’re ready for that next session.”

Ready to get stronger faster? Grab your dumbbells and mat, and let’s HIIT it!

Lindsay Geller is the lifestyle director at Women’s Health, where she oversees the Sex & Love, Relationships, and Life sections and manages Women’s Health+ content. She has 10 years of experience covering sex, relationships, health, fitness, and general lifestyle topics for print and digital publications. She currently lives in New Jersey with her husband and loves going on runs around her local park with her rescue dog.