Training guide
A jumping jack, or a star jump as most people in the UK call it, is a rhythmic hop: your feet jump apart as your arms sweep up overhead, then back together as your arms come down. Land softly on the balls of your feet with your knees a little bent. The step jack does the same pattern with one foot stepping out at a time, so there's no jump and almost no noise.
Done briskly, jumping jacks are vigorous exercise, but they're the gentlest of the common jumping intervals: in a lab study of 12 active men going all out, they cost less energy than burpees, mountain climbers or squat jumps. Short interval sessions that included them raised fitness in small 4-week trials. No trial has tested them on their own, or for bone.
This guide shows you the move step by step with a 3D demo, the step jack, how hard jumping jacks are and roughly what they burn, how many to do, and what to know about your knees, shins, shoulders, pelvic floor, pregnancy and bones, with the warning signs.
Stand tall with your feet together. Jump your feet out a little wider than your hips as your arms sweep up overhead, then jump back together as they come down, landing softly on the balls of your feet with your knees a little bent. In the UK these are usually called star jumps.
Source 1
Step one foot out to the side as both arms sweep up, step it back as they come down, then the other side. It's the swap for sore knees or feet, leaking, pregnancy, a first week back or neighbours below, as our step jack move page says, and the National Academy of Sports Medicine (NASM) suggests stepping instead of jumping for beginners.
Source 1
In 12 active men going all out for 30 seconds, jumping jacks cost 7.8 METs (metabolic equivalents: multiples of your resting energy use), less than mountain climbers, squat jumps or burpees. The Compendium of Physical Activities gives vigorous calisthenics, a group that includes jumping jacks, a reference value of 7.5 METs.
Short interval sessions that included jumping jacks raised peak oxygen uptake, a measure of aerobic fitness, in small 4-week trials in young adults, at home as well as in a lab. No trial has tested jumping jacks on their own.
In children, a jumping jack landed at about 2.5 to 3.5 times body weight, less than bigger jumps; nobody has measured adults. Jumping jacks raised pressure in the tummy more than any of 13 exercises in 25 women, and the NHS says high-impact exercise can increase leaks. If you leak, use step jacks while you build up pelvic floor exercises.
30 to 60 seconds as a warm-up or a circuit station, or 20 to 40 seconds on in intervals, as our workouts use them. NASM suggests intervals of 30 to 60 seconds. Keep hard interval sessions to once or twice a week, as our guide to HIIT (high-intensity interval training) says.
Source 1
A rhythmic two-footed hop. Your feet jump apart as both arms sweep out and up, then come back together as the arms come down, so each jack is two small jumps. Our jumping jack move page lists the calves and shoulders as the main movers, with the thighs and the muscles at the side of the hip helping.
The same move in everyday UK speech: our children's workouts call jumping jacks star jumps, and a UK interval trial used the name without describing the move. Some trainers use "star jump" for one big jump from a half squat, spreading your arms and legs into an X in the air; our power star jump move page shows that harder version.
Source 5
One foot steps out as the arms rise and back in as they come down, alternating sides. One foot stays on the floor, so there's no impact. It suits anyone who shouldn't jump or doesn't want to.
Done briskly, jumping jacks are vigorous activity: you can't say more than a few words without pausing for breath, as the NHS describes it. Done slowly, or as step jacks, they can be moderate activity, where you can talk but not sing. In 106 young people aged 6 to 18, jumping jacks used the most energy of 15 everyday activities measured.
Nothing for step jacks. For jumping jacks: hopping that's comfortable, with no foot, knee or hip pain and no leaking when you cough or hop (our suggestion).
A higher body weight means more force with every landing, so start with step jacks, as our beginner bodyweight workout suggests. Leaking with exercise is common in women, and age, weight and having had children make it more likely. Breasts move a lot in star jumps, more with a larger cup size, so a supportive sports bra helps. Stiff shoulders can keep the arms at shoulder height.
From our jumping jack move page and NASM's jumping jack guide. The space check and the cue to stop when landings get loud are our suggestions, as in our jump squat guide.
Loading the 3D figure…
The movement on the figure: Jumping jack
From our step jack move page, whose dose is 30 to 45 seconds within a circuit, 2 to 3 rounds (its editorial starting point).
Loading the 3D figure…
The movement on the figure: Step jack (low-impact jumping jack)
In 12 physically active men doing five 30-second all-out efforts of each exercise, with 30 seconds' rest, jumping jacks cost 7.8 METs and about 10.5 calories a minute, with heart rate at about 80% of the session's peak and effort rated 7.5 out of 10. Mountain climbers cost 9.9 METs, squat jumps 10.3 and burpees 11.5. Jumping jacks came first in the session, when heart rate and oxygen use were still rising, so the order may have made them look a little easier, and it's one small study.
Source 2
The 2024 Compendium of Physical Activities gives vigorous calisthenics (push-ups, sit-ups, pull-ups, jumping jacks, burpees and battling ropes) 7.5 METs, moderate calisthenics 3.8, low-impact aerobic dance 4.8 and high-impact aerobic dance 8.0. These are values for groups of activities, not a measurement of jumping jacks at your pace.
Source 3
In 106 young people aged 6 to 18, jumping jacks used the most energy of 15 activities measured, more than climbing stairs or dribbling a basketball.
Source 10
In 22 young women, the 7 who did 4 weeks of 8 bursts of 20 seconds of one move (burpees, jumping jacks, mountain climbers or squat thrusts), 4 days a week, raised their peak oxygen uptake by about 8%, as much as the 7 who trained on a treadmill (7%). In 30 young adults, 12 sessions over 4 weeks of five 1-minute efforts that started and ended with star jumps raised it by about 2.9 mL/kg/min supervised and 2.6 at home, against no training, with no adverse events. Jumping jacks were one move among several, and the trials were small and short.
In 8 children aged 8 to 12, a jumping jack landed at 2.6 times body weight, against 3.1 for a drop jump. In 70 children aged 8 to 11, jumping jacks landed at about 3.5 times body weight, against about 5 for countermovement and drop jumps. We found no study in adults.
In 12 young women, doing six exercises in a pool with their heads out of the water, jumping jacks among them, cut the peak landing force to 28 to 59% of the dry-land value.
Source 15
In 80 women aged 50 to 66 with mild knee osteoarthritis, 12 months of progressive high-impact training 3 times a week didn't change their knee cartilage on scans, and bone mineral content at the hip rose slightly (0.6%, against a 1.2% loss without training). Across 12 trials of 289 adults with average ages of 58 to 79, jump training caused no increase in injuries.
We found no trial of jumping jacks on their own for fitness, weight or bone, no study of knee or ankle loads in adults doing them, no study of step jacks, and no study showing that jumping jacks strengthen the pelvic floor.
The Compendium's reference value for vigorous calisthenics, 7.5 METs, works out by our rough arithmetic at about 9 calories a minute for a 70 kg person, about 7.5 for 60 kg and about 11 for 85 kg. It's a value for a group of activities, not a measurement of you: your pace, how high you jump and your size all change it.
Source 3
Active men going all out burned about 10.5 calories a minute during each 30-second effort, and much less in the rests between.
Source 2
By the same rough arithmetic, 100 calories is about 11 minutes of brisk jumping jacks for a 70 kg person. Count minutes rather than jacks, because how many jacks you fit in depends on your pace. Our calories burned calculator does the sum for your weight and time.
Source 3
No exercise burns fat from one place, as our exercise for weight loss guide explains: jumping jacks add to the energy your whole day uses.
Jumping jacks are small hops: in children their landings were lower than bigger jumps, and in older women with mild knee osteoarthritis a year of high-impact training didn't change knee cartilage. Nobody has measured knee loads in adults doing jumping jacks, so if your knees are sore, start with step jacks.
With knee pain, our knee pain after a workout guide's rule applies: 0 to 2 out of 10 during and after is fine, and up to 5 is acceptable if your knee is back to its usual level by the next morning. If it isn't, go back to step jacks for a while.
The NHS lists running or jumping on hard surfaces among the causes of shin splints. A sprung floor, a mat or grass is kinder than concrete, and so are cushioned trainers (our suggestion).
Source 18
With numb feet from diabetes or another cause, choose step jacks, wear well-fitting shoes and check your feet afterwards, as our jumping jack move page says. With proliferative or severe non-proliferative diabetic retinopathy, avoid jumping and jarring.
A fast overhead swing can bother stiff shoulders: take your arms to shoulder height instead, as our step jack move page suggests.
In 25 women who exercised regularly, jumping jacks produced the highest pressure inside the tummy of 13 exercises, about twice that of full sit-ups. In 57 women, jumping on the spot matched three hard coughs and beat running. Whether that pressure harms the pelvic floor isn't known.
In 59 physically active women, skipping, trampolining, jumping jacks and running were the activities most likely to cause leaking. In 452 women CrossFit competitors, 41.8% had leaked in the past 3 months and 38.3% during training or competition, most often with high-impact, high-repetition jumping and running, and some leaked most near the end of long sets. In elite athletes, jumps raised vaginal pressure the most of five sports activities, and clinics use star jumps to bring on a leak in bladder tests.
A review found that women who exercise generally have pelvic floor muscles as strong as, or stronger than, women who don't, and that walking lowers the risk of leaking; but women athletes are about three times as likely to leak. Jumping doesn't train the pelvic floor: we found no study suggesting it does.
Source 23
It's common and treatable. The NHS says high-impact exercise can increase leaks and pelvic floor exercises can reduce them: switch to step jacks, build up pelvic floor exercises, and see a GP or a pelvic health physiotherapist. Our pelvic floor guide has a plan.
Source 9
With a prolapse, the NHS advises avoiding activities that put a lot of strain on the pelvic floor, like heavy lifting, running and trampolining, and a pelvic health physiotherapy booklet counts any activity with both feet off the ground at once as high impact. Step jacks keep a foot down.
The NHS advises against starting a new vigorous activity in pregnancy. If you already do jumping jacks, stop when they cause leaking, heaviness or pelvic pain, as our jumping jack move page says, and switch to step jacks.
Source 26
The NHS advises avoiding high-impact exercise to start with. UK guidance suggests waiting at least 3 months before running and jumping, and only once walking, hopping and jogging on the spot cause no leaking, heaviness or pain; that timing is expert opinion.
In 39 women doing star jumps without a bra, the breasts moved up to 18.7 cm, and discomfort rose with cup size. In 20 full-busted women, sports bra design changed body sway in jumping jacks and running. A supportive, well-fitting sports bra makes jumping more comfortable.
The UK consensus on exercise for osteoporosis recommends moderate impact on most days, such as stamping, jogging, low-level jumping or hopping, about 50 impacts a session, for example 5 sets of 10. The Royal Osteoporosis Society calls an impact moderate when you push off and land with a medium amount of force, often with both feet leaving the ground.
Jumping jacks fit that description, so by our reading they count towards those 50 impacts. But no trial has tested jumping jacks for bone, and in children their landings were lower than the jumps used in bone programmes; one study's authors doubted that loads under 3 times body weight are enough to build children's bones.
With spinal fractures or several broken bones, the guidance keeps impact low, at the level of brisk walking, with one foot always on the ground: step jacks rather than jumping jacks, and ask a physiotherapist before anything harder.
From easiest: the standing march, 60 seconds brisk (our dynamic warm-up); standing punches, 30 to 45 seconds within a circuit (their move page's dose); step jacks, 30 to 45 seconds within a circuit, 2 to 3 rounds (their move page's dose); jumping jacks, 30 to 60 seconds (our workouts); and the power star jump, 3 sets of 5 with about a minute's rest (its move page's dose), a maximal jump rather than a rhythm.
The arms go out to shoulder height instead of overhead: kinder to stiff or sore shoulders.
The arms open wide and clap together in front of your chest as the feet jump out and in.
The feet jump out into a wide squat and back in: harder on the thighs, so learn soft landings first, as our jump squat guide teaches.
The feet jump in and out in a high plank: closer to a mountain climber, with your weight through your wrists.
Jumping jacks in a pool, with your head out of the water, cut the landing force to roughly a quarter to a half of the dry-land value in one study.
Source 15
We'd leave them out: they add load to your shoulders at the top of the swing, and no study has shown a benefit (our suggestion).
Mountain climbers, jump squats, skipping and burpees are harder intervals. Our HIIT workout at home uses 40 seconds on and 20 off, with 1 or 2 rounds in your first sessions.
NASM lists landing with straight or barely bent knees as a common mistake. Land on the balls of your feet with your knees a little bent.
Source 1
NASM also lists jerky, uncontrolled landings and jumping on when you're tired. End the set when your landings get heavy or loud.
Source 1
Your feet only need to clear the floor (our suggestion).
Keep your knees in line with your toes as your feet land wide, as our landing guides teach.
With stiff or sore shoulders, take your arms to shoulder height.
Breathe steadily: during brisk jacks you should still manage a few words.
30 to 60 seconds, then the moves of the session: our beginner bodyweight workout uses 30 seconds, our full-body bodyweight workout 45 and our HIIT workout at home 60. Our dynamic warm-up uses 60 seconds of step jacks, or jumping jacks if impact feels fine.
20 to 40 seconds on: 20 on and 10 off in our Tabata workout, 30 on and 10 off in our 7-minute workout, and 40 on and 20 off in our HIIT workout at home. NASM suggests intervals of 30 to 60 seconds with short rests.
Source 1
Jumping jacks are the first of 12 moves in the 7-minute circuit, 30 seconds each with 10 seconds to change. Its authors described it in an expert article but didn't test it, and advised caution for people who are new to exercise, injured, older, carrying more weight or living with other health conditions.
Source 31
20 jumping jacks at the start of each minute, resting for the rest of it; easier, 20 step jacks; harder, 30 (our EMOM workout).
Hard interval sessions once or twice a week for most people, up to three, as our HIIT guide says. Easier jumping jacks or step jacks can go in on any day: bouts of any length count towards the 150 minutes of moderate or 75 minutes of vigorous activity a week that the NHS recommends.
There's no evidence for a number. If you take on a daily challenge, build up over weeks from what you can do with quiet landings, split the total into sets, and stop for joint pain. Very large, sudden amounts of exercise can cause rhabdomyolysis, a serious breakdown of muscle: MedlinePlus lists severe exertion such as calisthenics among its causes.
Source 34
Add 10 seconds to each bout, or a round, from week to week, or move from step jacks to jumping jacks, while your landings stay quiet (our suggestion: with body weight, our plans add a little at a time, then move to the harder option).
Single-leg calf raises from a step, 2 sets of 10 to 12 each leg (our vertical jump workout), for your calves; snapdowns, 2 sets of 5 holding each landing for 2 seconds (our knee control warm-up), to learn soft landings; heel drops, 20 to 30 at first, building towards about 50 impacts on most days (their move page's dose), as a first impact step for bone; and pelvic floor exercises, 8 slow holds of up to 10 seconds and 8 quick squeezes, three times a day, building towards 10 of each (their move page's dose).
The 7-minute and Tabata workouts start with jumping jacks, the EMOM workout has a minute of them in every round, and our HIIT workout at home uses them in 40-second intervals. The low-impact cardio workout uses step jacks instead, the beginner bodyweight workout warms up with them, and the dynamic warm-up gives you the choice.
The 12-move circuit from a 2013 fitness journal article: 30 seconds per move and 10 to switch, with a short warm-up and an easier swap for every move.
12 minIntermediate13 movesA wall, A stepThree 4-minute blocks of 20 seconds hard and 10 seconds easy, with bodyweight moves and a minute between: the timing of the Tabata study, at home.
22 minIntermediate10 movesA wallA 16-minute EMOM: start squats, push-ups, lunges or jumping jacks at the top of each minute and rest for what's left, with easier and harder targets.
22 minBeginner9 movesA wallA 20-minute no-equipment HIIT workout: jumping jacks, jump squats, mountain climbers, burpees, skips and bear crawls.
20 minIntermediate10 movesNo equipmentA 25-minute standing cardio circuit with no jumping: marching, step jacks, sit-to-stands, punches, step-ups and wall push-ups, with a seated option for most moves.
25 minBeginner9 movesA bench or box, A stepA 20-minute full-body workout with no equipment: squats, knee push-ups, bridges, lunges and planks.
20 minBeginner10 movesNo equipmentA 10-minute warm-up for any workout: raise your heart rate, move each joint through its range, rehearse the main movements, then ramp up to your first lift.
10 minBeginner12 movesA wall, A bandThese plans use the beginner bodyweight, full-body bodyweight, low-impact cardio or circuit workouts, which warm up with jumping jacks or use step jacks.
Your first four weeks: two, then three short strength sessions a week at home plus walks, building gently to a full routine.
2 training days20 minBeginner3 days a weekFor after about 8 weeks of a beginner plan: three full-body sessions a week, one heavy, one moderate and one light, in a gym or at home, for 12 weeks.
3 training days50 minIntermediate3 days a weekAn 8-week toning workout plan: three full-body strength sessions and two cardio sessions a week, light and heavier weights, gym or home, without the myths.
3 training days40 minBeginnerIf you haven't exercised for some time or have a medical condition, speak to your GP first, as the NHS advises.
Source 11
Start with step jacks, as our beginner bodyweight workout suggests, and add jumping jacks once a few minutes of step jacks feel easy (our suggestion).
With heart disease, or blood pressure that isn't controlled, keep to moderate effort and ask your GP or heart team before hard intervals, as our HIIT guide says.
Step jacks are a good start, with a hand on a chair back if your balance is unsure. Jump training in older adults didn't increase injuries, and the NHS recommends activities for strength, balance and flexibility on at least 2 days a week alongside cardio.
Use step jacks, and follow the pelvic floor notes above.
If you get chest pain or pressure, feel faint or dizzy, are unusually breathless, or your heart races or beats irregularly during exercise, as our plans advise. The American Heart Association says these need immediate medical evaluation.
Source 36
For chest pain that doesn't go away, feels tight or like squeezing, or spreads to your arms, neck, jaw, stomach or back, or comes with sweating, feeling sick, light-headedness or breathlessness; severe difficulty breathing; someone who faints while exercising; palpitations that don't go away, or come with chest pain, shortness of breath or feeling faint; or a headache that starts suddenly and is extremely painful. Don't drive yourself to A&E.
If you haven't exercised for some time or have a medical condition, speak to your GP first, as the NHS advises. Get advice before hard intervals or jumping if your blood pressure is uncontrolled, or you have heart disease or chest pain when you're active, a pacemaker or defibrillator, diabetic eye disease, glaucoma, a hernia, recent eye or tummy surgery, or you're pregnant, as our breathing guide lists.
Source 11
See a GP after any faint, and for dizziness that won't go away or keeps coming back.
After a big or unusual session, such as a first high-rep challenge, muscle pain, swelling or weakness far worse than the session explains, with dark (red, brown or cola-coloured) urine, needs same-day help: NHS 111 (in the US, urgent care), or A&E if you feel very unwell. Dark pee isn't always there, so muscles far sorer, more swollen or weaker than the session explains still need the check.
Source 34
Get advice from NHS 111 if your knee is very painful, you can't move it or put weight on it, it's badly swollen or has changed shape, or it locks, gives way or clicks painfully. See a GP if knee pain doesn't improve within a few weeks.
Source 45
Contact NHS 111 if shin pain is severe or you've injured your shin, and see a GP if shin splints are getting worse. Heel pain with a snap, grinding or popping noise at the time, or not being able to walk on your tiptoes, is an NHS 111 call. Pain in one spot on a bone that's worse with jumping and tender to press can be a stress fracture: stop jumping and see a GP, as our stress fracture guide says.
Call 999 or go to A&E if you heard a crack, the joint has changed shape or points at an odd angle, it's numb or tingling, or the skin looks blue or grey or feels cold. Get help from NHS 111 if it's very painful or swollen, or you can't put weight on it or walk more than a few steps. Call 999 if someone has fallen and may have injured their head, back, neck or hip, or can't get up.
Leaking is a reason to change the exercise, not to stop exercising: see a GP or pelvic health physiotherapist. See a GP for a feeling of heaviness or pressure in your lower tummy or vagina, or a bulge or lump in or coming out of your vagina, which can be a prolapse.
See a GP if you think you have a hernia. Get help from NHS 111 if you have a hernia and pain in or around it, a bloated tummy, sickness, constipation or a high temperature. Call 999 or go to A&E for a femoral hernia (a lump at the top of the thigh) with very bad tummy pain, sickness, being unable to fart or poo, a high temperature or sudden confusion.
Their landings were modest in children, high-impact training didn't change knee cartilage in older women with mild knee osteoarthritis, and jump training in older adults didn't add injuries. Nobody has measured adults' knees in jumping jacks, so with sore knees, start with step jacks and the knee rule: that's a reason to change the move, not proof of harm.
We found no study suggesting they do. They raise pressure in the tummy more than most exercise and are a common trigger for leaking, though women who exercise generally have pelvic floor muscles as strong as, or stronger than, women who don't. Pelvic floor exercises train it; step jacks keep you moving meanwhile.
UK guidance for bone asks for about 50 moderate impacts on most days. By our reading jumping jacks count towards them, but no trial has tested jumping jacks for bone, and their landing forces are lower than the jumps used in bone studies.
No exercise burns fat from one place. Brisk jumping jacks burn roughly 9 calories a minute for a 70 kg person, by our rough arithmetic from a general reference value, as part of everything your day uses.
Source 3
Moderate activity, where you can talk but not sing, counts towards the NHS's 150 minutes a week; the World Health Organization says some activity is better than none; and short bouts count. Steady step jacks count too.
Stand tall with your feet together and your arms by your sides. Jump your feet out a little wider than your hips as your arms sweep up overhead, then jump back together as they come down, landing softly on the balls of your feet with your knees a little bent. Keep a steady rhythm and stop the set when your landings get heavy.
In everyday UK speech, yes: "star jumps" usually means jumping jacks. Some trainers use "star jump" for one big jump from a squat, spreading your arms and legs into an X in the air, and our power star jump move page shows that harder version.
Roughly 9 calories a minute for a 70 kg person, by our rough arithmetic from a general reference value for vigorous calisthenics, so 100 calories takes about 11 minutes of brisk jacks. It isn't a measurement of you: pace, jump height and body size all change it. All-out efforts measured about 10.5 calories a minute in one lab study of active men.
There's no magic number. A minute or two warms you up, and 2 to 5 rounds of 20 to 40 seconds make a cardio block. If you take on a daily challenge, build up over weeks, split it into sets, and get same-day help for muscle pain far worse than the session explains, especially with dark urine.
Yes: done briskly they're vigorous activity, though the gentlest of the common jumping intervals, below mountain climbers and burpees. Short interval sessions that included them raised fitness in small 4-week trials. Slower jacks or step jacks count as moderate activity if you can talk but not sing.
Not for most people: they're small hops, and in studies of older adults, jump training didn't add injuries or change knee cartilage. With sore knees, use step jacks and keep pain to 0 to 2 out of 10, or up to 5 if your knee is back to normal by the next morning. See a GP if knee pain isn't improving within a few weeks.
Do step jacks: step one foot out as your arms sweep up and back in as they come down, then the other side. If you jump, land softly on the balls of your feet with your knees bent, on a mat rather than bare floorboards.
They don't strengthen it, and they're a common trigger for leaking: they raise pressure in the tummy more than most exercise. Leaking is common and treatable, so swap to step jacks, do pelvic floor exercises, and see a GP or pelvic health physiotherapist.
The NHS advises against starting a new vigorous activity in pregnancy; if you already do them, stop when they cause leaking, heaviness or pelvic pain, and use step jacks. After a birth, avoid high impact to start with: UK guidance suggests waiting at least 3 months, until walking, hopping and jogging on the spot cause no leaking, heaviness or pain.
By our reading they count towards the 50 or so moderate impacts on most days that UK guidance recommends for bone. But no trial has tested jumping jacks for bone, so we can't say what they build. After spinal fractures or several broken bones, keep impact low and ask a physiotherapist.
Both are vigorous. Jumping rope needs more skill and works the calves harder, and our jump rope guide covers it; jumping jacks need no kit and have a no-jump version, the step jack.
Step jacks are a good start, with a hand on a chair back if your balance is unsure, and many people can build up to jumping jacks: jump training in older adults didn't add injuries. The NHS also recommends strength, balance and flexibility work on at least 2 days a week.
Exercise education, not a personal prescription, and clinical review of these guides is pending. Check with a GP before starting hard training if you have a heart condition, chest pain, dizziness or breathlessness when active, and stop for sharp or increasing pain. Health disclaimer.
