Kelsey Wells New Year's Challenge: 10-minute Core Workout

Welcome to Yahoo Lifestyle's exclusive two-week New Year workout series with Sweat trainer Kelsey Wells. These workouts will take you less than 15-minutes! Quick and simple to follow so it won’t take time out of your busy holiday season.

This 10-minute core workout is inspired by Kelsey's PWR at Home Program in the Sweat app and has been designed to help build up strength in your core using only a dumbbell.

It is an optional workout in Kelsey's complete 2-week workout plan for Yahoo Lifestyle.

This is a short and sharp circuit style workout, perfect for those who are getting back into an exercise routine or those who are time poor.

"Now that we are in week two of my 2-week workout plan, this Express Core Workout really takes things up a notch with the addition of a dumbbell to add resistance," Kelsey tells Yahoo Lifestyle.

"When you start incorporating weights into your training it's so important to focus on completing each exercise with correct form to ensure greater engagement and control of your core muscles. Although this is an optional workout, if you’re up for the challenge I hope you finish this workout feeling proud and strong for putting in the extra work, finding the motivation to move your body and getting it done."

Do each exercise for 30 seconds with a 15 second rest. Complete two laps.

Week 2, Day 2: Core workout with one Dumbbell

Russian twists

Step 1: Holding a dumbbell with both hands directly in front of your chest, start seated on a yoga mat with knees bent and heels firmly planted. Lean back slightly so that your abdominals are engaged and you are balancing on your sit bones. This is your starting position.

Step 2: While keeping your lower body as still as possible, twist your torso to the right and gently touch the head of the dumbbell on the mat next to your right hip.

Step 3: Untwist your torso to return to the starting position.

Step 4: While keeping your lower body as still as possible, twist your torso to the left and gently touch the head of the dumbbell on the mat next to your left hip.

Step 5: Untwist your torso to return to the starting position. Continue alternating between right and left for the specified number of repetitions.

Plank and Drag

Step 1: With a dumbbell behind your left hand, place both hands on the floor shoulder-width apart and both feet together behind you, resting on the balls of your feet. This is your starting position.

Step 2: Release your right hand and place your hand on the dumbbell. Drag the dumbbell across the mat, release your hand and place it in front.

Step 3: Release your left hand and place your hand on the dumbbell. Drag the dumbbell across the mat, release your hand and place it in front. Continue alternating between right and left for the specified amount of time.

Bent Leg Jackknife

Step 1: Holding a dumbbell with both hands, lie on your back on a yoga mat with your arms extended above your head. Engage your abdominal muscles by drawing your belly button in towards your spine and elevate your legs off the mat slightly. This is your starting position.

Step 2: Inhale. Bend your knees and using your abdominals, draw them in towards your chest, ensuring that your feet stay together. At the same time, bring the dumbbell forward towards your feet, slowly lifting your head, shoulder blades and torso off the mat.

Step 3: Exhale. Slowly lower your arms and extend your legs to return to the starting position, but without lowering your feet to the floor.

Toe Taps

Step 1: Holding a dumbbell with both hands, start by lying straight on your back on a yoga mat with your legs extended out in front of you. Gently raise your legs off the floor so that they form a 90-degree angle at your hips. Engage your abdominal muscles by drawing your belly button in towards your spine. Extend your elbows to hold the dumbbell directly in front of your chest. This is your starting position.

Step 2: Inhale. Exhale. Press the dumbbell up towards your feet — slowly lifting your head, shoulder blades and torso off the mat.

Step 3: Inhale. Lower your torso, shoulder blades and head to the mat to return to the starting position. Repeat for the specified number of repetitions.

Stay tuned for Week two Day 3 of Kelsey's two-week workout plan tomorrow. You can also find all of Kelsey's workouts on our Youtube channel.

If you missed Monday's workout try it here:

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