June Fitness Challenge
Daily fitness challenge for the month of June focused on core training in the supine, prone, and side positions.
Daily Challenge
As a functional fitness coach of several years, I run a community-based fitness group outside of my gym. We discuss goals, meet weekly for outdoor workouts, and tackle a new daily challenge each month.
The intent of these daily challenges is to create productive habits and induce both mental and physical adaptations. The at-home exercise is never more than ten minutes - often less. Short, achievable tasks provide an opportunity to still earn the day when your plans get disrupted.
Consistency will always produce better and more lasting results than intermittent intensity.
Anyone can find a few minutes a day to do something beneficial for themselves.
That’s all you need to begin seeing progress.
The Specific Adaptation to Imposed Demands (SAID) Principle is an exercise physiology concept that demonstrates the more you do anything, the better you get at that specific thing.
The body’s ability to physiologically adapt and optimize performance based on what we consistently put it through is amazing. Even more impressive is the mind’s plasticity in response to stress.
Machine learning for humans.
Fitness serves as a vehicle for resilience training. The physical benefits are valuable, but the mental skills developed through consistent effort are what create lasting change.
Showing up daily isn’t easy but it’s how lasting change is formed.
Enhance resilience by consistently embracing self-created challenges.
June Daily Challenge: Midsection Stabilizer
Complete as many flutter kicks in the supine (lying on back) as possible for up to 3 minutes.
Recover for 30 seconds.
Complete as many flutter kicks in the prone (belly down) position as possible for up to 3 minutes.
Recover for 30 seconds.
Accumulate as much time in the side plank position for up to 90 seconds. Repeat on other side immediately.
Alternate starting positions each day.
The Midsection Stabilizer trains the core from all sides. Supine flutter kicks develop the anterior abdominals, prone flutter kicks strengthen the posterior chain, and side planks build lateral stability in the obliques. Together, they create a balanced foundation of strength, postural control, and resilience in the core while requiring minimal equipment and only a few minutes per day.
Modifications are provided for all movements, making this challenge accessible regardless of age, weight, or ability.
Technique & Modifications
* Watch videos for technical demonstration and discussion. The written steps can help add detail to the micro-movements as needed *
Supine Flutter Kicks
Supine flutter kicks strengthen the abdominal muscles and hip flexors while improving trunk stability, hip mobility, postural control, and muscular endurance.
Starting Position:
Lie on your back with your legs extended straight
Place your hands under your butt or alongside or on your body
Keep the neck aligned with the spine by either slightly lifting your head and shoulders or letting the head rest on the ground.
Engage your core while pressing your lower back toward the floor
Raise both feet a few inches off the ground
Execution:
Begin alternating your legs in a small, controlled kicking motion
Move one leg up and the other down far enough that the heel on the higher foot clears the toe line on the other and continue alternating
Keep your core engaged and avoid arching your back
Maintain steady breathing throughout the movement
Modifications:
Bent-Knee Flutter Kicks – Bend your knees approximately 90 degrees and perform the same alternating kicking motion.
Seated Flutter Kicks – Sit on the edge of a chair or bench, lean back slightly, brace your core, and perform alternating kicks (legs straight or bent) while keeping your feet elevated.
Prone Flutter Kicks
Prone flutter kicks strengthen the glutes, hamstrings, lower back, and posterior chain while promoting trunk stability, hip mobility, postural control, and muscular endurance.
Starting Position:
Lie face down on the floor with your legs extended straight
Place your head on your hands or extend your arms in front of you
Engage your core muscles and squeeze your glutes
Lift both legs slightly off the ground
Execution:
Begin alternating your legs in a small, controlled kicking motion
Move one leg up so the thigh comes off the ground as the other lowers while keeping the legs straight and continue alternating
Keep your torso and hips flat on the ground with the core and glutes engaged throughout the exercise
Maintain steady breathing throughout the movement
Modifications:
Bent-Knee Flutter Kicks – Bend your knees approximately 90 degrees and perform alternating kicks by moving your heels toward the ceiling.
Tabletop Leg Raises/Pulses – Begin on your hands and knees with your knees under your hips and hands under your shoulders. Extend one leg straight behind you and lift as high as possible. Alternate legs or perform small, controlled upward pulses for a certain number of repetitions before switching legs.
Side Planks
Side planks strengthen the obliques, shoulder stabilizers, and lateral core muscles while improving trunk stability, balance, and postural control, and muscular endurance.
Starting Position:
Position yourself on your side with your legs straight
Place your supporting hand directly under your shoulder with your arm extended
Alternatively, place your forearm on the ground with your elbow directly under your shoulder
Feet can be stacked or staggered for additional stability
Keep your head, neck, torso, and legs aligned in a straight line
Engage your core and glute muscles
Execution:
Lift your hips off the ground into a strong side plank position
Keep your head, neck, torso, and legs aligned in a straight line
Maintain steady breathing throughout the movement
Modifications:
Side Knees Plank – Bend either your bottom knee or both and use as support on the ground.
Elevated Side Plank (Couch or Bench) – Place your supporting hand, forearm, or head/shoulder on a couch, bench, secured yoga ball, or any other elevated surface to reduce the amount of body weight being supported.
For all movements:
Keep spine and neck aligned
Avoid excessive tension in the neck
The neck should not feel more fatigued than the core
Keep torso pressed to the ground in supine and prone positions
Maintain steady breathing
Progression Guide
For beginners:
Start with modifications that allow you to continue movement/hold for more than ten seconds and take breaks as needed
Decrease total amount of time for each exercise
Choose only one or two exercises on a given day and rotate through them throughout the week
Progressively work to unmodified versions of each movement for prescribed amount of time
For intermediate/advanced:
If you can complete challenge unmodified and unbroken:
See how long you can go/how many reps you can complete until failure and build off that
Wear ankle weights for flutter kicks and/or place a manageable weight on your hips for side planks
Add in other core challenges like the Ab Stacker, Core Conditioner, Trunk Transformer, or Waistline Refiner
As always, compete with yourself yesterday.
Quality of form is more important than quantity of reps. Become comfortable with the technique first, then increase your volume.
By the end of June, if you consistently complete this challenge regardless of modifications, you will build a stronger, more stable, and more resilient core.
Battle your internal resistance and get that small win.
Everything feels easier when you occasionally make things a little harder on purpose.
Balanced Training
For the longest time, if I was wanting to strengthen my core, I was on my back cranking out crunches, sit-ups, and leg raises. Every so often I might do some Russian twists and a standard plank. As I began studying functional fitness, human performance, physiology, and training methods, I quickly realized how flawed my approach had been.
The core’s primary purpose is to transfer force in all directions and stabilize the spine. It encompasses much more than the front abdominal region. Front-loading the trunk with primarily linear movements such as crunches and sit-ups can neglect the obliques, posterior chain, and rotational stability needed for a resilient midsection. My previous training focused almost exclusively on the abdominal muscles, contributing to muscular imbalances that likely exacerbated lower back discomfort from poor posture and activities such as jiu-jitsu, trail running, and rucking. As I began considering my sleep posture, doing deep squat holds, sitting upright, and training the other aspects of my core, my lower back pain progressively went away.
Incorporating prone and side-positions with traditional abdominal exercises creates a more balanced approach by training the core’s ability to stabilize the body from multiple directions, improving overall function, durability, and performance.
Make sure you watch the technique video above to learn about modifications so you can start at a manageable level based on experience and proficiency with movement.
The primary purpose of all of this - resilience development physically, mentally, and spiritually.
Get Ready
I’m posting this a day early so everyone, including my international friends, can prepare to start strong on day one at their own skill and comfort level.
Track your times and modifications only to set a goal for the following day. The outcome doesn’t matter as long as you show up and do your best.
Consistent effort leads to improved performance over time.
How will you respond when you don’t feel like it?
These are the days that matter most.
These are the moments you see what you’re made of.
These are the days that change you.
This is how resilient mental states are developed.
Embrace the challenge of discipline to optimize the skill of resilience.
Deliberate discomfort daily can lead to improved comfort elsewhere forever.
Stacking valuable inputs in training adds quality to the limited quantity of time we have throughout the day. Use a brief fitness routine to insert control and success into every day.
Self-care through self-challenge.
A few minutes a day can change your life.
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*Special Offer*
Join our community and earn a one month subscription to Resilient Mental State:
Complete the challenge for more than half the month.
Bonus giveaway for anyone who completes it every day.
In our community chat, we’ll hold each other accountable by posting a ✅ after completing each day’s challenge. Timing and modifications don’t matter—just show up and do your best.
To claim your one month subscription, share your story at the end June:
Share a reflection on your progress (either in the community chat or privately with me) and then I’ll confirm your ✅ count.
Join our community, and let’s improve together.
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Disclaimer:
The content provided is intended for general knowledge and informational purposes only and is not a replacement for medical advice. Always consult with a qualified healthcare professional prior to making any decisions or changes relating to your health. Kyle Shepard is not responsible for any adverse effects resulting from the use of information in this publication.
I didn't even know prone flutter kicks were a thing 😮
But that's Good news! Another weapon in the arsenal of fitness 💪🔥💯
Just pour gasoline into your hamstrings and skip the prone flutter kicks. Same level of pain, less work... OK, I kid.