Ask a Trainer: What Are the Best Core Exercises for Triathletes?

A stronger core means a stronger swim, bike, and run. Here are the best core exercises for triathletes looking to get fitter and faster.

Photo: Kyle Herrig

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The core is more than just the six-pack abs everyone fantasizes about. As the “crossroads” of the kinetic chain, the core is the link between our upper body and our lower body. Stretching from just below the chest all the way down to mid-thigh, the core includes the front, back, and sides of the body – essentially, the entire midsection. Without a strong and stable core, a person’s upper and lower limb strength can not be utilized to its true potential. A strong core can help a triathlete be more efficient with movement while also protecting from injury, ultimately making you faster and lengthening your triathlon career. By only focusing on upper and lower body strength training, we are neglecting a critical component to functional strength.

Let’s look at one of our basic life movements: gait, and when done at a faster pace, running. Each time we step forward with our right leg, there is a chain reaction that takes place. The right knee moves forward along with the right hip, rotating the pelvis; while the right leg and hip move forward, our upper body does the exact opposite. The left hand, arm, and shoulder move forward, creating torque and potential energy through the core. This creates a twisting motion that looks like wringing out a towel, with the bottom going one direction while the top twists the opposite way. This is what happens to the core muscles with each and every step. Our core is there to help control and facilitate movement of our limbs while protecting our spine and internal organs with the complex movements of our bodies. To say the core is important is a dramatic understatement! By simply looking at our normal body movement, we see the core’s function in each step. 

To help the muscles do their job while training and racing, it’s important we strengthen these muscles using the best core exercises for triathletes. Strengthening your core doesn’t have to be an all-out workout in the gym. Let’s go over some simple core exercises we can all throw in after a swim, bike or run session.

RELATED: Strength Training for Triathletes

The best core exercises for triathletes

Mountain climbers

While in an all-four position, drive one knee forward while kicking the opposite leg straight back. Continue to alternate legs while holding a stable core position. To increase the difficulty, drive the right knee forward and across towards the left elbow, creating more functional rotation.

A triathlete does mountain climbers, one of the best core exercises for triathletes
(Photo: Kyle Herrig, Triplex Training)

Bird dogs 

In a quadruped position (knees on floor, back flat, palms down) kick the right leg straight back while reaching the left arm straight out in front. Then drive the right knee forward and left elbow back to where they touch.

A triathlete does bird dogs, one of the best core exercises for triathletes
(Photo: Kyle Herrig, Triplex Training)

Rotational crunches

While lying flat on your back place your right hand lightly behind your head and your left foot up on your right knee. Lift your right shoulder blade off the ground and bring your right elbow towards your left knee.

A triathlete does rotational crunches, one of the best core exercises for triathletes
(Photo: Kyle Herrig, Triplex Training)

Plank dips 

While resting on your right elbow, you can either have your right knee down or just the side of your foot with your body in a straight line. Drop the right hip down, just barely touching the ground and back up to straight-line position.

A triathlete does plank dips, one of the best core exercises for triathletes.
(Photo: Kyle Herrig, Triplex Training)

Alternating V-ups

While lying flat on your back with both arms straight up overheard lift up your left leg while lifting your upper body off the ground- bring both hands to touch lower left leg.

A triathlete does alternating v-ups, one of the best core exercises for triathletes.
(Photo: Kyle Herrig, Triplex Training)

Plank reach-throughs

While in a one-arm plank position, either on hand or elbow, with the feet wider than shoulder width apart, place the hand centered between the feet. Take the free hand and reach underneath the bottom, rotating the core, and then reach all the way back up overhead.

(Photo: Kyle Herrig, Triplex Training)


Standing with feet wider than shoulder width apart and hands together, rotate torso to the right while taking hands to about knee height, also while slightly squatting. Then stand up and rotate left with hands up high over left shoulder. Add a weight to make this more challenging. 

A triathlete does chops, one of the best core exercises for triathletes
(Photo: Kyle Herrig, Triplex Training)

RELATED: 7 Yoga Poses to Take Your Core Strength to the Next Level

For more exercises and workouts to do at home, check out the online workouts provided daily by Herrig’s functional training studio Triplex Training at

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