Single Leg Ball Jackknife (core)
How to Do the Single Leg Yoga Ball Jackknife | In-Depth Guide [VISUAL LEARNERS]
Proper Form & Common Mistakes| Home Resistance Training
VIDEO TUTORIALS HEREWRITTEN TUTORIAL + IMAGES BELOW
MAIN MUSCLES WORKED IN the Single Leg Jackknife
LOTS OF CORE MUSCLES - SEE BELOW
transverse abdominis, obliques, quadratus lumborum, rectus abdominis, pelvic floor, erector spinae, multifidi, iliopsoas, gluteals.
OTHER MUSCLES WORKED:
- Latissimus Dorsi
- Mid and Lower Traps
- Serratus Anterior
- Forearm Muscles
HOW the Single Leg Jackknife SHAPE OUR BODY
Nice, confident, upright posture. Controlled, graceful movement. Flatter stomach, toned midsection.
WHAT WE'RE DOING TODAY
Other names for this exercise: Stability Ball Single Leg Knee Tuck
ALL WE'RE DOING:
Watch the video! Another challenging one.
The single-leg jackknife exercise is a core exercise that involves the movement of the hips and the lower body, and it is beneficial for improving core strength, balance, and flexibility. It is helpful to have perfected the stability ball plank, the stability ball jackknife, and the stability ball plank with leg lifts before moving on to this one. It is fine to start with the shin on the ball.
Also starting with one set of 4-6 reps is reasonable. This is super duper hard! You can finish up with regular jackknifes if you want to push yourself further. Once you have these down, if you still want a bigger challenge, try the alternating-leg jackknife.
PROPER FORM: Single Leg Jackknife
EQUIPMENT, SETS & REPS
SUGGESTED STARTING WEIGHT FOR WOMEN:
None; only pulling the ball in as far as you are controlled, but you should feel challenged
SETS & REPS:
1set; 4-6 reps on each side.
Slow control, focus on form not speed or number of reps.
BODY POSITION FOR THE Single Leg Jackknife
Place the stability ball on the floor and kneel behind it. Lean your chest over the ball. With your hands on the floor begin to walk yourself forward off of the ball.
BODY STANCE: Walk out until only your lower legs and feet are on the ball. Neutral spine (includes neck). Shoulder blades down and in, sternum lifted.
ARMS/HANDS: Arms straight, your elbows soft. Hands under shoulders, palms on the floor with your fingers facing forward
LEGS: The nonworking leg tucked under you - hip and knee bent, knee under your belly. The working leg stays on the ball. Knee straight. You may need to move your working leg to the center of the ball to balance before lifting your nonworking leg off.
HOW TO DO
HOW TO DO the Single Leg Jackknife
CUE: The goal is to keep your spine neutral and be as controlled and stable as possible.
Fold (bend) your hip and knee to pull the ball in towards your hands.
Your knee will drop down under your body, folding up like a jackknife.
Only pull your leg in as far as you are able to maintain a neutral and stable spine, this will also be limited by your tucked leg.
Straighten your leg back out and push the ball back to the starting position.
Repeat for the desired number of reps.
HOW TO SAFELY GET OUT OF THE EXERCISE
Straighten your non working leg and place it back on the ball. Walk your hands back until the feet touch the floor. Continue to push the ball forward under you until your knees are on the floor. Push up to standing.
WHAT TO AVOID WITH THE Single Leg Jackknife
Guess what? Good news! Many avoids are the same for most movements. Once you learn the basics, there's really only a few extra avoids for each individual movement.
1. Avoid Sagging Low Back
AVOID: Avoid letting the low back sag.
- Too much extension in the low back can strain the muscles and ligaments of the spine.
WHAT TO DO:
- The back can sag if you collapse in the shoulders or upper back.
- Maintain a neutral and stable spine.
- Activate the abdominal muscles - the rectus abdominis will work to prevent spinal extension.
- Push down into the floor with your hands, pull your shoulder blades in and down the back and lift the sternum.
- Try engaging the pelvic floor.
- Even lengthening the neck can help to control a sagging low back because it helps to activate the back extensors (they run the length of the spine from cervical to lumbar region).
2. Avoid Rounding Spine
AVOID: Avoid rounding the back.
- Too much flexion in the spine can lead to irritation or compression of the spinal joints and discs.
WHAT TO DO:
- LIft the sternum, push your upper body up and lower your pelvis (hip in line with shoulder and knee).
- Lengthen the spine - from head to tail.
3. Avoid Side of Pelvis/Hip Dropping
AVOID: Letting the side of your pelvis lift or drop when you lift the leg.
- This defeats the purpose of the exercise - strengthening the spinal stabilizers.
WHAT TO DO:
- Isolate the movement to the hip joint.
- Remember that the lift can be very small - one inch is fine.
4. Avoid Locking Elbows
AVOID: Avoid locking or hyperextending your elbows.
- This puts too much force through the joint and may result in long term damage over time.
- This will decrease the muscle activity of the arm muscles that stabilize the elbow joint.
WHAT TO DO:
- Keep the elbows slightly bent throughout the movement.
5. Avoid Tucking/Lifting Chin
AVOID: Avoid lifting the chin.
- This can lead to neck strain and damage to the soft tissue and small joints of the cervical spine (neck).
WHAT TO DO:
- Keeping your neck (cervical spine) in neutral will strengthen the muscle of the neck in a neutral position - the healthiest position for the joints and nerves (part of a neutral spine position).
- Keep your neck long and look down at the floor.
- Keep space between your earlobe and the top of your shoulder.
6. Avoid Dropping Into Shoulder
AVOID: Avoid dropping into the shoulder.
- Stresses the shoulder joints, increases the lumbar curve.
WHAT TO DO:
- Keep the shoulders back and sternum lifted.
- Press down into the floor with the support hand.
- Lengthen the spine (including neck) and energize the arm that is reaching out.
- This will activate the muscles of the core.
WHAT & WHY
BENEFITS OF TRAINING our core MUSCLEs
FREQUENT, EVEN DAILY, CORE WORK IS TOTALLY A THING
Many exercises for some muscles you only want to do every 2-3 days, giving your muscles time to heal and rebuild in between. But the nice thing about working the core is that these are endurance muscles, they are designed to work at a low level for a long time - basically all day long. This means that you can do core exercises every day. Adding a few core exercises to your daily routine can really pay off.
The Single-Leg Jackknife is a very challenging and unique exercise. One leg is held off of the ball in a tucked position while the other leg bends and straightens to pull and push the ball. This works the rotators of the core more because one side of the body is not supported by the ball and the muscles will have to hold that side up to keep the pelvis and spine level. The leg on the ball will be working harder to support and stabilize the lower body, and to pull and push the ball. Not only will this work the muscles quite a bit more, but it also challenges your balance and coordination more.
WHY DO WE EVEN CARE?
FULL BODY EXERCISE
Stability Ball Planks are a full-body workout - targeting a lot of different muscles at the same time. They can be used to strengthen the core, shoulders, and arms, and to challenge coordination, stability, and balance. That makes them a good choice if you have a limited amount of time. Including full-body exercises is more functional because they improve coordination, body awareness, and control.
CORE MUSCLE STRENGTH IS THE FOUNDATION OF HEALTHY MOVEMENT. KIND OF LIKE CHOCOLATE IS THE FOUNDATION OF BROWNIES. NO CHOCOLATE, NO BROWNIES. NO CORE STRENGTH, NO HEALTHY MOVEMENT.
The main focus of stability ball planks is strengthening the core muscles. Having a strong core is the foundation of healthy movement. The core has also been called the pillar of strength or the powerhouse. If you want strong and healthy arms and legs, it is important to have a strong core to support them. Stability ball planks are a fun way of achieving that.
PSYCHOLOGICALLY SATISFYING! FEEL LIKE A ROCKSTAR OVERNIGHT
One of the best things about the ball exercises is that you tend to see progress pretty quickly. This is an interesting phenomenon. I think it comes from the fact that balance and motor control is more about mental control than physical strength. This is exciting because it means that you don’t have to actually grow the muscle to feel the improvements, you just have to practice.
The more you use the stability ball, the quicker your brain will learn how to move on it, you will most likely feel more confident on the ball within 3 -4 exercise sessions. Which of course makes you feel like you’re an overnight success. None of this 6 months to see improvements stuff! Just kidding, of course that’s part of our workout program too. But this is a wonderful quick-win feeling. We all need those “I’ve obviously made major progress” moments sometimes!
GRAVITY IS A WONDERFUL THING- HOW TO MAKE YOUR CORE WORK HARD WITHOUT WEIGHTS OR BANDS.
When we are upright with good posture, the muscles of the core are not very active - that is the beauty behind the design of the spine. When all of the vertebrae are stacked up and aligned properly, the muscles don’t have to do much work and the body can conserve energy. As soon as we move our legs or arms, the muscles become more active. If we lean forward or backward, gravity will pull down on our heads and upper body and the muscles become even more active. Planks put the body into a horizontal position where gravity really has an effect - just getting into this position and holding it is very demanding on the core muscles. This is easy to feel when you are in a plank.
PROTECT YOUR BACK. OR HELP YOUR BACK IF IT’S ALREADY HURTIN’.
Strong and healthy core muscles are needed to keep upright and to prevent damage to your spine, and even the rest of your body. The main job of the core is to hold us up. Anytime that we are not being supported by something, like a bed or chair, our core muscles are working to hold us upright.
The muscle activity increases as soon as the weight of the head is no longer directly over the spine. So if you lean forward, the weight of your head starts to pull your torso forward, The core muscles work to prevent you from falling. The muscles also move each individual vertebra to keep them all properly stacked and aligned. Between every two vertebrae, there is a disc and two small joints on the side. There are also two small passages where the nerves exit from the spinal cord and travel to the different areas of the body. If the vertebra moves too much it can lead to injuries to the ligaments, discs, joints, and nerves.
Most low back pain is due to too much movement between the vertebrae. The muscles need to help stabilize the vertebra and also absorb shock from the lower body to protect all of these structures. Back and neck pain are a huge problem, leading to disability and loss of independent living. Learning safe exercises that train the core muscles to move in the healthiest way possible can help to prevent joint damage and prolong independence.
HOLD ON TO THAT BONE MASS (IT’S A THING OVER 40)
Another benefit of stability ball plank exercises is that you are weight-bearing through the arms - not many exercises require that you put a lot of weight through the arm bones. Loading the bones in this way will stimulate bone growth, making the bones stronger. Weight-bearing exercises are frequently used for prevention or as a treatment for osteopenia or osteoporosis (low bone density).
Exercises that are done with the arms or legs in weight-bearing will stimulate the proprioceptors more - these are receptors in the joints that send information to the brain to tell the brain where the limb is in space. Proprioception (the awareness of where the body is in space) is important for motor control, coordination of movement, and balance.
EVERYDAY LIFE &
HOW WE USE OUR core MUSCLES IN EVERYDAY LIFE
1. THE CORE MUSCLES WORK ALL DAY LONG TO HOLD US UPRIGHT DURING ALL DAILY ACTIVITIES:
- Pushing a wheelbarrow
2. THE CORE MUSCLES HOLD THE SPINE STILL WHILE USING THE ARMS OR LEGS:
- Washing windows
- Kicking a ball
- Climbing stairs/ladder
- Stepping into/out of a high car/truck
- Painting overhead
SPIFFILICIOUS FACTS ABOUT MUSCLES & MOVES
All of the muscles of the core work together to stabilize the spine. The muscles include the erector spinae and deep back extensors: (semispinalis, multifidi, rotatores, interspinalis and intertransversarii. The back extensors can extend (bending backwards) the spine, or control or prevent spinal flexion (bending forward); The quadratus lumborum muscle can side bend the spine, or prevent or control sidebending, The internal and external obliques can flex and rotate the spine, or prevent or control rotation and extension of the spine. The rectus abdominis flexes the spine and controls or prevents spinal extension. The transverse abdominis muscle is the deepest abdominal muscle, it wraps around the entire abdomen in the transverse plane (horizontally) like a corset. The function of the transverse abdominis is to compress and stabilize the abdomen.
The iliopsoas muscles originate on all of the lumbar vertebrae and attach on the top of the femur. The primary function of these muscles are to flex the hip (lift the thigh as in marching), the secondary function of the muscle is to stabilize the pelvis
The muscles of the back and abdomen work at low levels intermittently when standing upright. They become more active when the body is no longer vertical, and gravity pulls the torso into flexion, side bending, or extension.
The main function of the muscles of the torso is to protect the spine from excessive movement. Too much movement in the spine can lead to injury or damage to the joints of the spine, or the nerves that exit between the vertebrae. These muscles work any time we are in an upright position: standing, sitting, running, walking. The muscles become more active when on an unstable surface, and when we are moving the arms or legs.
ALLLL MUSCLES & WHEN
ALL MUSCLES WORKING & WHEN DURING THE Single Leg Jackknife
In the beginning position, the muscles of the torso are fairly quiet because the torso is resting on the ball. The quadriceps act concentrically to push off the floor to move the body forward.
The hands contact the floor and begin walking the body forward. The arm and shoulder blade muscles (deltoids, biceps, triceps, teres major, muscles of the forearm, scapular muscles, rotator cuff muscles, and latissimus dorsi) work together to stabilize the shoulder blade and move the body forward. When the torso passes the ball, the muscles of the core - extensor spinae, deep spinal extensors (semispinalis, multifidi, rotatores, interspinales and intertransversarii), quadratus lumborum, obliques, rectus abdominis, and transverse abdominis all contribute to holding the spine in neutral. The pelvic floor can help if you work on activating it.
The hip muscles work to hold the pelvis level: iliopsoas, adductors magnus, brevis, and longus, gracilis, gluteus maximus, medius, and minimus, hamstrings, and the quadriceps femoris. Other muscles (deep hip stabilizers, sartorius, lower leg muscles) may help as you walk out so that only the lower leg/feet are on the ball (the more you need to work to hold yourself still the more muscles will be recruited).
The nonworking leg is brought under the body in a tucked position. The multifidi, rotatores, and obliques will have to work harder to keep the spine level. The iliopsoas and the rectus femoris of the working leg contract concentrically to pull the thigh in. The quadriceps femoris work concentrically to straighten the leg back out as you push the ball back out again.