These moves come to you from four of our top Daily Burn 365 trainers. For a new, 30-minute workout every day, head to DailyBurn.com/365.

When it comes to the ultimate ab exercises, crunches top the list. From runners to yogis to CrossFit buffs, athletes favor this simple, no-equipment move to strengthen the abdominals, obliques and hips. But the basic move can become, well, routine. So to help you kick up your core game, we rounded up these killer crunch variations, guaranteed to tighten and tone your midsection. As Daily Burn 365 trainer Justin Rubin says, “Crunches work your obliques, your sides, your lower abs, your upper abs. It’s a total-core workout.”

RELATED: 5 Standing Ab Exercises for People Who Hate Crunches

5 Crunch Variations to Sculpt Your Abs

1. Modified Bicycle Crunch
If you have trouble keeping your legs lifted during a bicycle crunch, this modified version helps ease discomfort on your lower back and keeps your neck supported—all while toning your obliques. Your upper body will also benefit from a fuller range of motion as you move from one side to the other.

How to: Lay flat on your back on an exercise mat and place your hands behind your ears on your head, keeping your arms in a straight line (a). Lift your head with your hands in a 45-degree angle to the floor and bend your knees in front of you with just your heels touching the mat (toes pointed up) (b). Lift your right knee to about a 90-degree angle to the floor as you bring your left elbow to meet it. Now switch opposite sides with the same motion, engaging your core muscles the whole time (c). Repeat for eight reps.

RELATED: Hate Crunches? 6 Better Core Exercises for Beginners

2. Standing Crunch
Standing crunches are great as part of a dynamic warm-up because they activate the muscles in your abs, arms and legs while getting your heart rate up. But they’re also ideal for an active recovery mid-HIIT workout when you transition from one set to the next, or when you want to slow down your heart rate as you switch from cardio to strength training.

How to: Stand tall with your feet hip-width apart (a). Bring your arms up with your hands reaching for the ceiling and your palms facing each other (b). Engage your core to lift your right knee to hip height. At the same time, lower your arms at your sides, bringing them by your waist (c). Return to starting position and repeat on the opposite side. (d). Do eight reps.

RELATED: 5 Stability Ball Exercises For a Crazy Strong Core

3. V-Sit Crunch
In addition to strengthening your core like crazy, this challenging move will help elongate your body. Did we mention it helps stretch your hamstrings, too? (We’re looking at you, runners!). If your hands can’t meet your legs, keep your feet flat on the floor and bend your knees as you lift your hands to your feet.

How to: Lie flat on the floor with your arms by your head and your hands reaching for the wall behind you. Keep your feet straight out in front of you (a). Engage your core as you lift your right leg straight up into the air, until it’s perpendicular to the floor (b). At the same time, pull your upper body toward your leg so your hands meet your ankle or shin (c). Return to the starting position and repeat on the opposite leg. (d). Repeat for eight reps.

RELATED: The Pilates Ab Workout to Sculpt Your Core

4. Reverse Crunch
This variation of reverse crunches borrows the pulsating movements of barre with the bridge pose. The trick is to keep your upper body still as your core and lower body do the work. In this reverse crunch variation, the spine is also lengthened and strengthened (win-win!).

How to: Lie on your back with your knees bent and your feet flat on the floor hip-width apart. Your hands should be at your sides and your palms facing down (a). Press your feet against the floor and use your abdominal muscles to lift your hips up. Hold this pose for two seconds (b). Bring your hips back down to the floor and lift your legs as you pull your knees toward your chest. Avoid using momentum from your legs to pull them in and engage your core muscles instead (c). Hold the crunch for two seconds before bringing your feet back down to the floor (d). Do eight reps.

RELATED: Need a Cardio Fix? Try This 5-Minute Kickboxing Workout

5. Kickboxing Crunch
Add some pep and power to your standing crunch with this kickboxing-inspired move. For those looking to strengthen your balancing skills, this is the exercise for you. This kickboxing crunch offers the right combination of strength training and cardio, working out your core and arms while building endurance, too.

How to: Get into a kickboxing stance, standing tall with your hip-distance apart. Keep your left arm bent high at your side. (a). Jab with your right arm to the side from the bottom to the top. At the same time, engage your abs and do a squat. Then, pull your right knee towards your chest to do a crunch. (b). Next, kick with your right leg out in front of you with your hands at your sides (left arm bent high and right arm at waist-height). (c). Repeat this motion for eight reps before switching to the other side.

This article originally appeared on Daily Burn.

Want more quick and easy moves you can do right at home, head to DailyBurn.com/365 — it’s free for 30 days!

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Daily Burn 365: New Workouts, 7 Days a Week
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This article originally appeared on Life by Daily Burn.