Jumping Jack
What Is the Jumping Jack?
Jumping Jack is a compound exercise that primarily targets the calves, hips and shoulders while conditioning the heart and lungs. It is a beginner-level movement that needs no equipment. This classic movement is often used as a warm-up or as part of aerobic workouts to get the blood flowing and elevate the heart rate.
The movement works side to side rather than front to back. The calves power each small hop, the outer hips drive the legs apart and the inner thighs pull them back together, while the shoulders lift the arms overhead on every rep. Because the arms and legs have to stay in time, the jumping jack also doubles as a simple coordination drill, which is one reason the US military has long used it, under the name side-straddle hop, in group warm-ups. It is also the opening exercise of the widely shared 7-minute bodyweight circuit.
Tempo, set length and arm path change the work. A faster pace or longer intervals raise the cardio demand, a seal jack swaps the overhead arm swing for a clap in front of the chest, and the Plank Jack moves the same leg pattern into a plank to load the core and shoulders. The Battle Rope Jumping Jack adds the weight of the ropes to the arm swing for a harder upper-body effort.
The jumping jack suits almost anyone who can land a small hop comfortably, and it needs only a few feet of floor. For a newcomer to exercise, someone carrying extra body weight, or anyone with sore knees, ankles or a pelvic floor that leaks with impact, a step-out version that taps one foot to the side at a time keeps the rhythm without the jump, and Marching in Place is an even gentler place to start.
Muscles Worked
- Deltoid
- High
- Gluteus Medius
- High
- Soleus
- High
- Adductor Longus
- Medium
- Tensor Fasciae Latae
- Medium
- Vastus Lateralis
- Medium
- Vastus Medialis
- Medium
Instructions
- Stand upright with feet together and arms resting at your sides.
- Keep your chest up, your gaze forward and your knees soft.
- Hop and spread your feet out wide, well past shoulder-width, while you swing your straight arms out to the sides and up overhead.
- Land on the balls of your feet with your knees slightly bent and your hands meeting or nearly meeting above your head.
- Immediately hop again, bringing your feet back together while you sweep your arms down to your sides.
- Land softly on the balls of your feet, letting your heels touch down lightly, and go straight into the next rep.
- Repeat this motion continuously at a steady pace for the desired duration or number of reps.
Common Mistakes
Landing with stiff knees
Landing with locked knees can stress the joints and reduce shock absorption.
Landing on the heels
Thudding down flat-footed or heel first sends the impact up through the shins and knees instead of letting the calves absorb it.
Not using full range of motion
Failing to fully extend arms or spread legs limits effectiveness and rhythm.
Arms and legs out of sync
Letting the arms swing loosely or lag behind the legs breaks the rhythm and turns the movement into a choppy, uncoordinated hop.
Leaning forward
Tilting the torso forward can strain the lower back and throw off balance.
Going too fast too soon
Starting at full speed instead of easing into the pace makes form break down and loads the calves and ankles before they are ready.
Injuries
Jumping Jack is a low risk exercise when performed with proper technique. The load on any one joint is small, but every rep is a landing, so the calves, Achilles tendons, shins, ankles and knees absorb dozens of small impacts in every set. Ankle sprains or shin splints can occur if the landing is uncontrolled or the surface is uneven. Overuse or high-repetition sets may also aggravate joints if recovery isn't factored in.
To prevent injuries, perform Jumping Jacks on a soft surface like a mat or wooden floor with supportive athletic shoes. Land on the balls of your feet with your knees slightly bent to absorb impact, let the heels touch down lightly rather than slamming, and build the length of your sets over several weeks instead of jumping straight into long intervals.
Impact can also trouble the pelvic floor. In a survey of 59 physically active women in Canada, jumping jacks were among the activities most often reported to cause urine leakage, along with skipping, trampolining and running. Anyone who leaks during the movement can switch to the step-out version and is worth referring to a pelvic health physical therapist.
To regress, step one foot out at a time instead of jumping, raise the arms only to shoulder height if overhead reaching bothers the shoulders, or use Marching in Place. To progress, lengthen the intervals, pick up the pace, or move on to Jump Rope. Stop if you feel sharp pain in the shins, ankles or knees, or if you get chest pain, dizziness or breathlessness out of proportion to the effort.
- Primary Focus
- Cardio
- Equipment
- Body weight
- Modality
- Cardio
- Difficulty
- Beginner
Alternative Exercises
Other Names for the Jumping Jack
The Jumping Jack is also known as:
- Star Jump
- Side-Straddle Hop
Frequently Asked Questions
- Q: How long should I do Jumping Jacks for cardio?
Start with 30 to 60 seconds per set and increase based on fitness level.
- Q: Can I do Jumping Jacks every day?
Yes, if done with proper form and balanced with recovery, they can be done daily.
- Q: Are Jumping Jacks good for warming up?
Yes, they’re excellent for raising heart rate and prepping the body for movement.
- Q: Are Jumping Jacks bad for your knees?
Not for healthy knees when you land softly on the balls of your feet with your knees slightly bent. If your knees ache during or after a set, switch to the step-out version that taps one foot out at a time, or to Marching in Place, and have persistent pain checked.
- Q: Is a star jump the same as a Jumping Jack?
In the UK and much of the Commonwealth, star jump is the everyday name for the Jumping Jack. Some coaches use it for a different drill that starts from a squat and explodes into an X shape in the air, so check which one a program means.