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Coach Jill’s Best Core Exercises

Core strength is absolutely vital to optimal health and well-being. After all, your core is what supports your entire framework! Strong abdominal muscles will improve your posture and protect your lower back from injury, not to mention help your jeans fit better, thereby improving your self-confidence!

Here are a few of my favorite core exercises. I suggest working on your core 2 to 3 times per week for the best results.


A basic plank is a great core exercise. Make sure your elbows and wrists are directly underneath your shoulders. Keep your butt down and stay in the straight “plank” position for as long as you can. Start out for 15 seconds and build from there, adding 15 seconds to each interval. Aim to hold this position for 60 to 90 seconds. Pay close attention to your lower back: If you feel pain, relax, stretch, and try again, holding for a shorter interval until you build up your core strength to support your back. Remember to breathe!

Jill plank

Basic planks


The side plank is a modification of the traditional plank, and it targets the obliques as well. Begin on your side, keeping feet together, elbows and wrists directly under your shoulder (Fig 1). Slowly lift up your hips, keeping your elbow bent at 90 degrees (Fig 2). Hold for the same duration as a traditional plank, increasing your time as your endurance builds.

Jill side plank begin

Figure 1

Jill side plank finish

Figure 2


Russian twists are great for your obliques–the love-handle area! Sit on the floor with your knees bent, and lean back slightly, taking care to protect your back. Hold a medicine ball or any weighted object, for that matter (even a soup can will work for starters!), Rotate your trunk from side to side, exhaling as you rotate. You can begin with both feet on the floor, knees bent (Fig 1 & 2.) To add difficulty, lift both of your feet off the ground, and cross your ankles while rotating, as seen in Fig 3.

Jill russian twist start

Figure 1

Jill russian twist 2

Figure 2

Jill russian twist feet off floor

Figure 3


This is my favorite core exercise–one we love to hate. 🙂 An inflatable physio ball is ideal, but any type of ball will do–something you can get a hold of with your feet as well as your hands. Begin lying face-up on the floor, holding the ball in your hands, arms extended overhead, and legs fully extended (Fig 1). Bring your feet up to your hands as seen in the picture, and transfer the ball between your feet (Fig 2). Extend and lower the legs and arms fully while holding the ball between your feet. Try to lower almost all the way to the ground, keeping your feet off the floor (Fig 3). Bring the legs and arms back together and transfer the ball to your hands, fully extending once more before transferring back to your feet. I promise you will feel this one in your core. It is challenging and highly effective!

Jill physio ball passes start

Figure 1

jill physio ball passes middle position

Figure 2

jill physio ball passes position 3

Figure 3


This is another great exercise for your core and your obliques, as well as your glutes and quads. Stand with feet together, both hands gripping one dumbbell (or any weighted object)  in front of your thighs. Lower into a squat, bending your knees. Twist your torso to the left, drawing the dumbbell across your body and next to your left knee   (Fig 1.) This is your starting position. Keeping abs tight, twist your torso to the right to bring the dumbbell up and across body, extending arms at shoulder height. Slowly return to the starting position. Complete reps, then repeat on the opposite side. For extra challenge, extend the opposite leg off the floor as you cross your body with the dumbbell (Fig 3).

Jill dumbbell woodchop start

Figure 1

jill dumbbell woodchop finish

Figure 2

jill dumbbwell woodchop one foot off floor

Figure 3


Sit-ups are a no-no because they can put tremendous strain on your lower back. Instead, substitute a basic crunch. Take care to watch your neck and never strain the area; rather, you want your abdominals doing all the work!

Lie on your back with knees bent, feet flat on the floor. Ensure that your lower back is also flat against the floor throughout the entire exercise. Place your hands behind your head, but do not lace your fingers together (this will cause neck strain). Tilt your chin forward slightly, leaving a few inches between your chin and chest (looking up toward the ceiling will help – Fig. 1). Engage your abs, pulling your abdominal muscles inward, and curl up and forward so that your head, neck, and shoulder blades ONLY lift off the floor (Fig. 2). Exhale as you are performing this motion; this will ensure you are engaging your abs properly. Hold for a moment; then slowly and with control, uncurl back down to the floor to the start position. Repeat for as many times as you are able, taking care to never arch your lower back.

jill crunch begin

Figure 1

jill crunch finish

Figure 2