March Core Strength Challenge – Week 3

Hey team! It’s Week 3 of the Core Strength Challenge and we have a new workout routine lined up for this week. 

This week you’ll be moving in all directions, working the entire core to continue to build even more strength.

Just joining us? Welcome! Head over to the challenge page to get the details on our March Core Strength Challenge. If you’re looking for the exercises until now, here’s the routine for Week 1 and Week 2.

This week you’ll need a medicine ball, a single dumbbell, or a bag filled with some heavy stuff. 

Here’s the plan for Week 3. Try to get this workout in three times this week—you’ve got this!

And don’t forget to follow along on Instagram or on our Facebook Group for the videos each week, and keep tracking your progress on social media with a post or video each week!


View this post on Instagram


A post shared by Krista Stryker (@12minuteathlete) on

Core Strength Challenge Week 3 Exercises

Complete 3 rounds, resting as little as possible between reps and sets.

  • 10 side plank reaches
  • 10 v ups
  • 10 lying windshield wipers / side
  • 15 sit up + throws
  • 20 medicine ball toe touches
  • 20 rocking planks

To participate in the challenge, post on social media and tag #12MAcore and @12minuteathlete and post at least one photo or video each week.

Here’s how to do the exercises:

Side Plank Reaches

How to do it:

  • Get in a side plank on your elbow. Your shoulders should be directly over your elbow and your feet can either be stacked or placed directly next to one another.
  • Brace your core and squeeze your butt as you reach your top arm towards the sky.
  • Next, while keeping your core tight, reach your top arm down and underneath your body as far as you can.
  • That’s one rep. Make sure to work both sides.

V Ups

How to do it:

Advanced Version:

  • Lie on your back with your arms and legs straight.
  • Simultaneously raise your arms and legs as high as you can keeping them as straight as possible.
  • Try and touch your feet to your hands before lowering back down and repeating.

Beginner Version:

  • Pull your belly button towards the ground and raise your knees to your chest.
  • Extend your legs until they’re straight in front of you, then return your legs to the tuck position. That’s one rep.

Lying Windshield Wipers / Side

How to do it:

  • Lie on your back with your legs pointing straight up and your hands palm down by your side.
  • Keeping your legs as straight as possible, brace your core and use your hands for support as you lower your legs to one side with control.
  • Raise back up to the starting position, then lower to the other side.

Sit Up + Throws

How to do it:

  • Start in a regular sit up position lying on your back with your legs bent. Hold a medicine ball with both hands at your chest.
  • As you do a sit up, quickly throw the ball up in the air. Catch it as you lie down, then repeat again.

Medicine Ball Toe Touches

How to do it:

  • Lie on your back with your feet pointing straight up while holding a medicine ball to your chest.
  • Engage your abs as you lift the medicine ball towards your feet as high as possible.
  • Lower down with control and repeat.

Rocking Planks

How to do it:

  • Get into a forearm plank position (low plank).
  • Keeping your abs tight, thighs squeezed and body straight, shift your weight over your shoulders and then back again.
  • Keep going back and forth for time.

Sign up for Krista's Movement + Mindset Mastery newsletter to get your FREE eBook, 5 Keys to Building Mental and Physical Fitness. You'll also receive weekly physical and mental fitness-related content to help get you fired up for the week ahead.

1 thought on “March Core Strength Challenge – Week 3”

Leave a Comment