Kick-Out Exercise: How to Perform, Benefits, and Variations

How to do kick out exercise?

The kick-out exercise is a dynamic core stability movement that challenges abdominal strength and control, requiring you to extend your legs rapidly while maintaining a stable torso and preventing lumbar spine hyperextension.

What is the Kick-Out Exercise?

The kick-out exercise, also known as the supine leg extension or lying leg kick-out, is an advanced core strengthening exercise primarily targeting the rectus abdominis and transverse abdominis. Performed from a supine (lying on your back) position, it involves extending both legs simultaneously away from the body, then controlled retraction. Its dynamic nature demands significant core engagement to stabilize the pelvis and lumbar spine against the leverage created by the moving limbs, making it an excellent exercise for developing functional core strength and endurance.

Muscles Worked

The kick-out exercise is a comprehensive core movement that engages multiple muscle groups to achieve stability and motion.

• Primary Movers (Core Stabilizers):
  • Rectus Abdominis: The superficial "six-pack" muscle, responsible for trunk flexion and preventing lumbar extension.
  • Transverse Abdominis (TrA): The deepest abdominal muscle, crucial for stabilizing the lumbar spine and pelvis by creating intra-abdominal pressure.
  • Internal and External Obliques: Contribute to core stability, especially in resisting rotational forces and assisting with trunk flexion.
• Synergists (Assisting Muscles):
  • Hip Flexors (Iliopsoas, Rectus Femoris, Sartorius, Pectineus, Tensor Fasciae Latae): Responsible for the hip flexion component of the leg movement. Strong hip flexors are necessary, but the core must counteract their pulling force on the lumbar spine.
  • Quadriceps (Vastus Medialis, Vastus Lateralis, Vastus Intermedius): Extend the knee as the legs straighten.

Step-by-Step Instructions

Executing the kick-out exercise with proper form is paramount to maximize effectiveness and minimize the risk of injury, particularly to the lower back.

1. Starting Position:

   • Lie supine (on your back) on a mat with your knees bent and feet flat on the floor, about hip-width apart.
   • Place your hands by your sides, palms down, or for increased lower back support, slide your hands palms down slightly under your glutes or the small of your back.
   • Ensure your lower back is in a neutral position, or gently pressed into the mat, maintaining contact throughout the exercise. Avoid excessive arching.
   • Engage your core by drawing your naval towards your spine, as if bracing for a gentle punch to the stomach.
   • Bring your knees up towards your chest, lifting your feet off the floor until your shins are roughly parallel to the floor (tabletop position). Your knees should be directly over your hips.

2. Execution (Kick-Out Phase):

   • Inhale deeply, then as you exhale, slowly and with control, extend both legs straight forward and slightly upwards (around a 45-degree angle from the floor, or higher if maintaining back contact is difficult).
   • The key is to extend your legs as far as possible without allowing your lower back to arch or lift off the mat. Your core must remain strongly engaged to prevent this.
   • Keep your feet dorsiflexed (toes pulled towards shins) or plantarflexed (pointed), whichever feels more natural, but maintain tension through the legs.

3. Return Phase:

   • Inhale as you slowly and deliberately draw your knees back towards your chest, returning to the starting tabletop position.
   • Maintain continuous core engagement throughout the entire movement. Avoid using momentum to pull your legs back.

4. Repetitions:

   • Perform the desired number of repetitions, focusing on slow, controlled movements rather than speed. Each repetition should emphasize core stability and control.

Common Mistakes to Avoid

Improper form during the kick-out exercise can diminish its effectiveness and increase the risk of lower back strain.

• Arching the Lower Back: This is the most common and critical mistake. It indicates a loss of core engagement, placing excessive strain on the lumbar spine. Ensure your lower back remains pressed into or in contact with the mat throughout the entire movement.
• Loss of Control/Using Momentum: Rushing the movement, especially the return phase, reduces muscle activation and turns it into a ballistic exercise rather than a controlled strength movement.
• Too Low Leg Extension: Extending the legs too close to the floor without sufficient core strength will inevitably lead to lower back arching. Start with a higher leg angle and gradually decrease it as your core strength improves.
• Holding Breath: While bracing is important, holding your breath can increase intra-abdominal pressure excessively. Breathe rhythmically: exhale on extension, inhale on retraction.
• Neck Strain: Avoid craning your neck or lifting your head excessively. Keep your chin slightly tucked, maintaining a neutral spine from head to tailbone.

Benefits of the Kick-Out Exercise

Incorporating the kick-out exercise into your routine offers several significant benefits for core strength and overall functional fitness.

• Enhanced Core Stability: Directly trains the deep core muscles (Transverse Abdominis) to stabilize the spine against dynamic limb movements, crucial for injury prevention and athletic performance.
• Improved Abdominal Strength: Develops strength and endurance in the rectus abdominis and obliques, contributing to a stronger and more resilient midsection.
• Better Hip Flexor Control: While hip flexors are involved, the exercise also teaches the core to counteract their pull, improving the coordination between hip movement and spinal stability.
• Functional Strength: Mimics movements common in sports (e.g., kicking, running, jumping) and daily activities, translating to better power transfer and reduced risk of injury.
• Core Endurance: The controlled, sustained tension required helps build muscular endurance in the abdominal muscles.

Variations and Progressions

The kick-out exercise can be modified to suit various fitness levels.

• Easier (Regressions):
  • Single-Leg Kick-Out: Extend one leg at a time, keeping the other knee bent in tabletop. This reduces the leverage and core demand.
  • Higher Leg Angle: Extend your legs higher towards the ceiling (e.g., 60-70 degrees) to reduce the load on the core.
  • Shorter Extension: Do not extend the legs fully; keep a slight bend in the knees or limit the range of motion.
• Harder (Progressions):
  • Lower Leg Angle: As core strength improves, gradually extend your legs closer to the floor (e.g., 30-45 degrees), increasing the leverage and challenge.
  • Ankle Weights: Add light ankle weights for increased resistance.
  • Holding a Weight: Hold a small weight (e.g., dumbbell or medicine ball) overhead with straight arms for an added challenge to upper body and core stability.
  • Faster Tempo (Controlled): Once perfect form is established, a slightly faster, but still controlled, tempo can increase the dynamic challenge.

Who Should Do This Exercise?

The kick-out exercise is suitable for:

• Intermediate to Advanced Fitness Enthusiasts: Individuals with a foundational level of core strength.
• Athletes: Especially those in sports requiring dynamic core stability, such as runners, soccer players, gymnasts, and combat athletes.
• Individuals Aiming for Functional Core Strength: Those looking to improve their ability to stabilize their spine during daily activities and prevent lower back pain.

This exercise may not be suitable for:

• Beginners: Start with simpler core exercises like dead bugs, bird-dogs, or planks to build foundational strength.
• Individuals with Acute Lower Back Pain: The dynamic nature and leverage involved can exacerbate existing conditions. Consult a healthcare professional.
• Those with Severe Hip Flexor Tightness: This can make it difficult to maintain proper lower back contact.

Programming Considerations

Integrate the kick-out exercise effectively into your workout routine.

• Warm-up: Always perform a proper warm-up, including dynamic stretches and light core activation exercises, before attempting kick-outs.
• Placement: It can be performed as part of a dedicated core workout, at the end of a full-body strength training session, or as part of a circuit.
• Sets and Reps: Aim for 2-4 sets of 10-20 repetitions, focusing on quality over quantity. If you cannot maintain perfect form for the desired reps, reduce the range of motion or switch to a regression.
• Frequency: Incorporate into your routine 2-3 times per week, allowing adequate recovery between sessions.

Safety and Precautions

Prioritize safety to avoid injury and maximize the benefits of the kick-out exercise.

• Listen to Your Body: Stop immediately if you experience any sharp pain, especially in your lower back.
• Maintain Spinal Neutrality: The absolute most important cue is to prevent your lower back from arching. If it lifts off the mat, your core is not strong enough for the current range of motion or leg angle.
• Controlled Movement: Avoid jerky or fast movements. Every phase of the exercise should be deliberate and controlled.
• Consult a Professional: If you have pre-existing back conditions, hip issues, or are unsure about proper form, consult a qualified personal trainer, physical therapist, or exercise physiologist. They can provide personalized guidance and modifications.