Training guide
A star jump is a jump in which your arms and legs spread into a star in the air before you land softly with your feet together. In the UK, "star jumps" often means jumping jacks too, where you land with your feet apart and jump back: our jumping jack guide covers that rhythmic version, and this guide covers the bigger single jump.
Only one small study has measured a star jump's landing, and it didn't separate star jumps from stride jumps, so this guide says where the figures are thin.
It shows the jump and the landing step by step on the 3D figure, the steps up from step jacks and jumping jacks, whether star jumps count as plyometrics, what they do for fitness and bones, how many to do, and what to know about your knees, children, leaking, pregnancy and the months after a birth.
The Cambridge Dictionary gives both. A star jump is a jump in which you spread your arms and legs wide in the air and land with your feet together; in the UK the name also means a jumping jack, where you land with your arms and legs spread and jump back. Our jumping jack guide teaches that rhythmic version. This guide teaches the single star jump.
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Feet hip-width apart, a quick dip into a quarter or half squat, then jump, spreading your arms and legs into an X at the top. Bring them back in so your feet are under your hips before you land, softly, on the front of your feet rolling back to the heels, with your knees bent over your toes. Being told to land softly lowered landing force in female athletes.
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In 21 women aged about 43, star and stride jumps with a rebound landed at about 3.9 to 5.4 times body weight; children's jumping jacks landed at about 2.6. A star jump with a quick dip uses the same spring as plyometric jumps, so we count each landing as a jump, as our jump squat guide does.
Start with step jacks, then jumping jacks, then small star jumps, then the power version. For children, jumping counts as play that builds muscles and bones, alongside 60 minutes of activity a day. Under 16, jump training beyond play is best with a coach watching, as our vertical jump workout says.
As a power move, 3 sets of 5 with about a minute's rest (the power star jump move page's dose), counting each landing towards about 80 to 100 a session for beginners. As cardio, 20 to 40 seconds on in intervals. Brisk jumping of this kind uses roughly 9 calories a minute for a 70 kg person, by our arithmetic, so count minutes, not jumps.
Clinics use star jumps to bring on leaks in bladder tests. Leaking is common and treatable: swap to step jacks while you build up pelvic floor exercises. Don't start new jumping in pregnancy; after a birth, the NHS advises avoiding high impact to start with, and UK guidance suggests waiting at least 3 months.
The Cambridge Dictionary's first meaning of "star jump" is a single jump: you stand with your feet together, jump up, spread your arms and legs far apart, and land with your feet together and your arms down again. Its second, marked UK, is the jumping jack: you land with your arms and legs spread out and then jump back.
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In everyday UK speech, star jumps usually means jumping jacks. A Scottish survey of fitness instructors wrote "star jumps or jumping jacks", and a children's fitness test asks for a star jump or jumping jacks. Some trainers also use the name for a bigger jump from a crouch or half squat.
The single star jump: jump up, spread into an X in the air, and bring your feet back together to land. Its power version starts from a half squat and goes as high as you can, which our power star jump move page shows. For the rhythmic version, landing with your feet apart and springing back, see our jumping jack guide.
The single star jump. Each one is a full jump rather than a small hop: star jumps landed at about 4 to 5 times body weight in adult women, while jumping jacks landed at about 2.6 in children. Nobody has compared the two in the same people, so take that as a rough guide.
From our power star jump move page (get your feet back under your hips before touchdown; don't land with your feet still wide), our jump squat guide's landing steps and the Cambridge Dictionary's definition. For a gentler star jump, keep the dip and the jump small. For the jumping jack, see our jumping jack guide's steps.
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The movement on the figure: Power star jump (X jump)
Your calves, thighs and glutes drive the jump and absorb the landing, the muscles at the sides of your hips spread and close your legs, and your shoulders lift your arms, as our move page lists. The ankles, knees and hips take the landing.
In 21 women aged about 43, star jumps and stride jumps with a rebound landing came down at about 3.9 to 5.4 times body weight, above the levels the authors used as thresholds for building bone, and the second, rebound landing was 12 to 48% bigger. The study's summary doesn't separate star jumps from stride jumps, and it's the only force study of a star jump we found.
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In 8 children aged 8 to 12, jumping jacks landed at about 2.6 times body weight, and the authors suggest that may be too little to improve bone. In 70 children, jumping jacks landed at about 3.5 times body weight, against about 5 for countermovement and drop jumps.
Nobody has measured a star jump's knee loads. A two-footed countermovement jump loaded the kneecap about 6.4 times body weight in lab models of 20 healthy young adults, about as much as running, as our jump squat guide reports. Landing with your knees bent and over your toes shares the load.
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Plyometric jumps use the stretch-shortening cycle: a quick dip that stores energy just before you jump. A review classes ground contacts under about 250 milliseconds as fast and longer ones, such as countermovement jumps, as slow. A power star jump with a quick dip is a slow plyometric jump, like a jump squat; nobody has timed one. So we count each landing as a foot contact, as expert guidance on jump training does.
Heavier people land with more force, so start with step jacks, as our jumping jack guide suggests. In 39 women doing star jumps without a bra, the breasts moved up to 18.7 cm, and discomfort rose with cup size: a supportive sports bra helps. Women, especially after having children, are more likely to leak with jumping. Teenagers in a growth spurt need fewer jumps.
From easiest: the standing march, 60 seconds brisk (our dynamic warm-up); step jacks, 30 to 45 seconds within a circuit, 2 to 3 rounds (their move page's dose); jumping jacks, 30 to 60 seconds as a warm-up or 20 to 40 seconds on in intervals (our workouts); snapdowns, 2 × 5 holding each landing for 2 seconds, and jump squats, 3 × 5 with 60 seconds' rest (our vertical jump workout); the power star jump, 3 sets of 5 with about a minute's rest (its move page's dose); the rocket jump, 3 sets of 5 with about a minute's rest (its move page's dose); then tuck jumps, 2 × 4 (our gymnastics conditioning workout), and burpees, 40 seconds on and 20 off (our HIIT workout at home). There are no 3D demos for half jacks, seal jacks, squat jacks, star jump burpees or the star jump from a deep crouch: half and seal jacks follow the jumping jack, the crouch version the power star jump, and star jump burpees a burpee then a power star jump.
3D demoStanding marchBeginner · No equipment
3D demoStep jack (low-impact jumping jack)Beginner · No equipment
3D demoJumping jackBeginner · No equipment
3D demoSnapdown to athletic landingBeginner · No equipment
3D demoJump squatIntermediate · No equipment
3D demoPower star jump (X jump)Intermediate · No equipment
3D demoRocket jump (jump and reach)Intermediate · No equipment
3D demoTuck jumpIntermediate · No equipment
3D demoBurpeeAdvanced · No equipmentStep jacks first, with no jump; then jumping jacks, the gentler hop; then small star jumps with a small dip; then the power star jump once your jump squats land quietly, as its move page asks. Move on when every landing in a set is quiet and your knees track over your toes, one change at a time, as our jump squat guide says.
UK guidance asks children and young people for an average of at least 60 minutes of moderate-to-vigorous activity a day across the week, including activities that build movement skills, muscular fitness and bone strength. The NHS lists jumping among the activities that strengthen children's muscles and bones.
In 89 children aged 6 to 10, 100 jumps off 61 cm boxes, 3 times a week for 7 months, raised bone mineral content at the hip 4.5% more than in children who didn't jump. Short bouts of jumping three times a school day raised hip bone mass by about 2% in early puberty (not a randomised trial), and 24 of 26 studies in one review found benefits.
Nobody has tested star jumps for bone, and children's jumping jacks landed lightly enough that the authors doubt they'd help on their own. Mix star jumps with other jumping, hopping and running games.
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A 10-minute break of push-ups, star jumps, burpees and running on the spot didn't change test anxiety or maths scores in 68 children aged 11 to 12. Active breaks are good for being active, not a proven exam boost.
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Ordinary star jumps in play and PE need no special rules. Under 16, structured jump training is best with a coach watching, using body weight and light weights, as our vertical jump workout says, with fewer jumps in a growth spurt, as our gymnastics conditioning workout advises.
In 30 adults aged 18 to 30, 12 sessions over 4 weeks of five 1-minute efforts of star jumps, squats and standing sprints raised peak oxygen uptake by about 2.9 mL/kg/min supervised and 2.6 at home, against no training, with no harms reported. In 22 young women, 8 bursts of 20 seconds of one move, including jumping jacks, 4 days a week for 4 weeks, raised it by about 8%. The trials were small and short.
The 7-minute circuit, which starts with jumping jacks, is an expert design rather than a tested programme, and its authors urge caution for people who are new, injured, older or carrying more weight. Measured in 14 adults, it ran at an average heart rate of about 141 beats a minute, against 159 for cycling intervals: the low end of interval intensity.
The Compendium of Physical Activities gives vigorous calisthenics, which include jumping jacks, 7.5 METs (multiples of your resting energy use), and hard interval moves such as squat jumps 11.0. In 12 active men going all out for 30 seconds, jumping jacks cost 7.8 METs and about 10.5 calories a minute. Nobody has measured star jumps on their own.
By our rough arithmetic from 7.5 METs, brisk star jump or jumping jack intervals use about 9 calories a minute for a 70 kg person, about 7.5 for 60 kg and about 11 for 85 kg, while you're working. So 100 calories is about 11 minutes at 70 kg, not 100 jumps. Our calories burned calculator does the sum for your weight and time.
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Interval and steady exercise lose about the same fat when the work is matched, with high certainty in one review. In 13 trials of adults with overweight, the fat lost was similar, and intervals took about 40% less time. Neither produced much fat loss in short trials, and an umbrella review of 79 trials found under 1 percentage point more body-fat loss with intervals, mostly from low-quality reviews. No exercise burns fat from one place.
A minute of marching and step jacks, then 20 seconds of easy jumping jacks and 2 × 5 snapdowns before power star jumps, the moves our Tabata and vertical jump workouts use.
3 sets of 5 with about a minute's rest, the power star jump move page's dose. Count each landing towards about 80 to 100 jumps and landings (foot contacts) a session for beginners, twice a week, 48 to 72 hours apart, with the jumps early in the session.
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20 to 40 seconds on in intervals, 1 to 3 rounds in your first sessions, and hard sessions once or twice a week, as our HIIT, Tabata and 7-minute workouts do. Star jumps that land with your feet together are harder than jumping jacks, so expect fewer a minute (our suggestion).
Every power star jump is a full effort with a quiet landing. End the set when your landings get loud or your jumps get lower, rather than counting reps in reserve. Change one thing at a time: the height, then the reps, then the speed.
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Not needed. A daily challenge of 100 big star jumps is several sessions' worth of landings for a beginner, and tired landings get loud and sloppy. If you do one, keep each session to the dose above and rest a day between (our editorial suggestion).
A minute or two of jumping jacks or step jacks warms you up quickly, as in the warm-ups of our HIIT and 7-minute workouts. Save big power star jumps for when you're already warm.
Bring your feet back under your hips before you touch down, as our move page says.
Land on the front of your feet, roll to your heels and bend your knees; end the set when landings get loud.
Keep your knees over your toes.
Big jumps don't belong in a "100 a day" challenge; keep to sets of 5, or to timed intervals of the gentler jumping jack.
Swap to step jacks and see a pelvic health physiotherapist.
A supportive, well-fitting sports bra makes jumping more comfortable.
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A mat, a sprung floor or grass is kinder: the NHS lists running or jumping on hard surfaces among the causes of shin splints.
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Use step jacks or a fast march instead of jumping.
Pain from 0 to 2 out of 10 is fine, and up to 5 is acceptable if your knee is back to its usual level by the next morning; for tendon pain just below or above the kneecap, keep it to 3 or less. Sharp, catching or giving-way pain, or new swelling, means stop. That's our knee guides' rule.
Clinics use star jumps to bring on leaking in bladder tests when a cough doesn't. Of 106 Scottish fitness instructors, 28.2% had leaked, with jumping with the legs apart, as in star jumps or jumping jacks, among the triggers. In 59 active women, skipping, trampolining, jumping jacks and running were the commonest triggers.
About 36% of female athletes leak, across 8 studies, and the NHS says high-impact exercise can increase leaks. But an umbrella review found that how common leaking was didn't differ by sport or by how much impact the sport involved.
Jumping jacks produced the highest pressure inside the tummy of 13 activities in 25 women, about twice that of sit-ups, and maximal jumping on the spot matched a hard cough in 57 women. Pressure is a stand-in measure, not leaking itself.
Pelvic floor muscle training cured stress leaking in 56% of women against 6% with no treatment, across trials in a Cochrane review. NICE recommends supervised training for at least 3 months, with at least 8 squeezes 3 times a day, and encourages pelvic floor exercises for women of all ages, including in pregnancy. Swap to step jacks while you build up, and see a GP or a pelvic health physiotherapist.
The NHS says it's not recommended to start a new vigorous activity in pregnancy, and to avoid activities with a risk of falling or bumping your tummy. The American College of Obstetricians and Gynecologists says women who were already vigorously active can usually carry on. So don't start new jumping; if you already jump, stop when it causes leaking, heaviness or pelvic pain, as our jump squat move page says, and swap to step jacks.
In 97 healthy women pregnant for the first time, 6 weeks of high-low impact aerobics with pelvic floor exercises, including a pelvic floor squeeze before each landing, improved pelvic floor function with no harms. That's one supervised trial in women who were already well.
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We found no study of jumping to start labour. The NHS says there's no evidence that home remedies such as hot baths, food, sex or herbal supplements bring on labour; it doesn't mention jumping.
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The NHS advises avoiding high-impact exercise to start with, and getting advice at your 6-week postnatal check before any high-impact exercise. UK guidance builds from moderate to vigorous activity over at least 3 months, and suggests waiting at least 3 months before running and jumping, until walking, hopping and jogging on the spot cause no leaking, heaviness or pain.
That timing is expert opinion: an international expert panel prefers an individual timeline after at least 3 weeks' rest, and pelvic health physiotherapists advise not going back to high impact too quickly.
See a GP for heaviness or pressure in your lower tummy or vagina, or a bulge, which can be a prolapse. With a prolapse, the NHS says to avoid activities that put a lot of strain on the pelvic floor, like heavy lifting, running and trampolining.
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The UK consensus advises moderate impact on most days, about 50 impacts a session, and impact only up to brisk walking after spinal fractures. With spinal fractures or several low-trauma fractures, keep impact low, with one foot always on the ground (step jacks), and ask a physiotherapist before anything harder, as our jumping jack guide says.
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Pelvic floor exercises, 8 slow holds of up to 10 seconds and 8 quick squeezes, three times a day, building to 10 of each (their move page's dose, from POGP); heel drops, 20 to 30 at first, building towards about 50 impacts on most days (their move page's dose, from the UK osteoporosis consensus); single-leg calf raises from a step, 2 × 10 to 12 each leg, and ankle bounces, 2 × 10, as a springy start (our vertical jump workout).
Most of these use the jumping jack, the everyday UK star jump: the HIIT, Tabata, 7-minute and EMOM workouts as intervals, the animal moves for kids as "star jumps", and the low-impact cardio workout with step jacks instead. The vertical jump workout uses rocket jumps, the closest relative of the power star jump, and the strength workout for teenagers adds landings.
A 20-minute no-equipment HIIT workout: jumping jacks, jump squats, mountain climbers, burpees, skips and bear crawls.
20 minIntermediate10 movesNo equipmentThree 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 wallThe 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 stepA 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 wallFifteen minutes of animal moves, jumps and balance games for children, building the muscle- and bone-strengthening activity they need, with nothing to buy.
15 minBeginner16 movesA wallA 40-minute first strength workout for teenagers: a warm-up, landing and jump drills, then squats, hinges, push-ups, rows, step-ups and carries, kept light.
40 minBeginner19 movesA wall, A dumbbellA staged jump session for 8 weeks: landings and small jumps, then box and broad jumps, then depth jumps, each followed by squats, hinges and calf work.
40 minIntermediate16 movesA step, A bench or boxA 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 stepThese plans use jumping jacks in their workouts, as our jumping jack guide lists.
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 minIntermediateIf 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.
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For chest pain that comes on suddenly and doesn't go away, feels tight or like squeezing, spreads to your arms, neck, jaw, stomach or back, or comes with sweating, feeling sick, light-headedness or breathlessness; arm pain that comes on suddenly with pressure, heaviness or squeezing across your chest; severe difficulty breathing, or a chest that feels tight or heavy; 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, especially while lifting or straining. The NHS says a bleed on the brain may be more likely when lifting something heavy. Don't drive yourself to A&E.
Go to A&E if you've injured your knee and it has changed shape, it becomes very swollen very quickly, you felt a pop or snap, you can see bone sticking out, or it's bleeding heavily. Don't drive yourself: ask someone to take you, or call 999 if the pain means you can't move your leg to get there.
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If your knee is very painful, you can't move it or put any weight on it, it's badly swollen or has changed shape, it locks, gives way or clicks painfully (painless clicking is normal), or you have a very high temperature with redness or heat around the knee. See a GP if knee pain doesn't improve within a few weeks.
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Call 999 or go to A&E if you heard a crack, the injured part has changed shape or points at an odd angle, it's numb, tingling or has pins and needles, or the skin has changed colour or is cold to touch, as the NHS sprains and strains page lists.
Get help from NHS 111, or go to an urgent treatment centre (in the US, urgent care), if it's very painful or the pain is getting worse, there's a large amount of swelling or bruising or it's getting worse, you cannot put any weight on it or walk more than a few steps, it feels very stiff or is difficult to move, it's not feeling any better after treating it yourself, or you also have a very high temperature or feel hot, cold or shivery.
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A sudden snap or pop at the back of the ankle, or not being able to stand on tiptoe, is a same-day NHS 111 call: it can be a torn Achilles tendon. Get help from NHS 111 for severe shin pain or shin pain after an injury, and see a GP if shin splints are getting worse. Pain in one spot on a bone that's worse with jumping and hurts when you press it can be a stress fracture: stop jumping and see a GP, as our jumping jack guide says.
Same day (call NHS 111, or go to A&E if you feel very unwell): after a big or unusual session, such as a first spin class, a workout of 100 back squats, or intervals of wall sits, squats, lunges and jumps, a challenge or a new class, muscle pain, swelling or weakness far worse than the session explains, and dark pee (red, brown, tea or cola coloured), sometimes starting hours or days later. Dark pee isn't always there, so muscles far sorer, more swollen or weaker than the session explains still need the same-day check. It can be rhabdomyolysis, a breakdown of muscle that can harm the kidneys.
Call 999 or go to A&E: loss of feeling or numbness around the genitals or bottom, new trouble peeing or controlling your bladder or bowels, changes in genital sensation during sex or problems with erections or orgasm, or pain, tingling, weakness or numbness in both legs. These are signs of cauda equina syndrome, which needs treating in hospital urgently. Don't drive yourself.
See a GP if pain spreading down a leg hasn't improved after a few weeks of home treatment, is getting worse or stops your normal activities. Sciatica on both sides, or weakness or numbness in both legs that's severe or getting worse, is a 999 call or a trip to A&E.
See a GP if you think you have a hernia, a bulge or lump that may get bigger when you strain and smaller when you lie down. Get help from NHS 111 if you have a hernia and pain in or around it, a bloated tummy, you feel or are sick, you're vomiting blood or your vomit looks like coffee grounds, you're constipated, you have a high temperature or feel hot, cold or shivery, or you've suddenly become confused. Call 999 or go to A&E for a femoral hernia (a small lump at the top of your thigh, in your groin) with very bad tummy pain, sickness, being unable to fart or poo, a high temperature or sudden confusion.
Call 999 or go to A&E if your child gets sudden pain in their hip, knee or thigh (hip problems can sometimes be felt in the thigh or knee) or cannot put any weight on their leg. If your child is limping, ask for an urgent GP appointment or get help from NHS 111 the same day. This applies to teenagers too, and in some children knee pain is the only sign.
A child or teenager with pain at a bump just below the kneecap or at its lower tip, worse with squats, jumps and kneeling: see our Osgood-Schlatter and Sinding-Larsen-Johansson guides, and get it checked if it is getting worse.
With proliferative or severe non-proliferative diabetic retinopathy, avoid jumping and jarring. With numb feet, choose low-impact options, wear well-fitting shoes and check your feet afterwards. With osteonecrosis (avascular necrosis) of the hip or knee, ask your specialist before impact exercise, as our jump squat guide says.
Speak to your GP first if you haven't exercised for some time or have medical conditions or concerns, as the NHS advises. Get advice before hard or straining work if your blood pressure is uncontrolled (140/90 or higher at a clinic, or 135/85 at home), 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.
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Muscle soreness for a day or two after a new or harder session is common and fades. Sharp pain, or pain that builds during a set or lingers into the next day, isn't: swap to an easier version, and see a clinician if it persists, as our plans advise. The NHS says to stop exercising straight away if you feel any pain or become unwell, and to get help from 111 if symptoms worry you or don't go away.
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Adult interval and bone-loading studies use them, and the power version is a demanding jump at any age.
A star jump with a quick dip uses the stretch-shortening cycle that plyometric training is built on, and star jumps landed at about 4 to 5 times body weight in one study. The rhythmic jumping jack is a gentler hop.
Interval and steady exercise lose about the same fat when the work is matched, and a few minutes of star jumps uses tens of calories. Belly fat isn't burned by jumping on its own: no exercise burns fat from one place.
Clinics use them to bring on leaking, and no study shows that jumping trains the pelvic floor. Pelvic floor exercises do, as our jumping jack guide says.
No study supports it, and the NHS says there's no evidence that home remedies bring on labour.
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Height comes from the growth plates, which close in the teenage years. Jumping doesn't change how tall you'll be, and it doesn't stunt growth either, as our jump squat guide explains.
Stand with your feet hip-width apart, dip quickly into a quarter squat, and jump, spreading your arms and legs into a star at the top. Bring them back in before you land, and land softly on both feet with your knees bent. End the set when your landings get loud.
Sometimes. In the UK, "star jumps" often means jumping jacks, where you land with your feet apart and then jump back. A star jump can also mean one jump into a star shape, landing with your feet together, which is harder; our jumping jack guide teaches the rhythmic version.
Your calves, thighs and glutes drive the jump and absorb the landing, the muscles at the sides of your hips open and close your legs, and your shoulders lift your arms. They train power and fitness more than muscle size.
Yes. Done in intervals they're vigorous cardio, and short interval sessions with star jumps raised fitness in young adults within 4 weeks. As single big jumps they train power, landing at about 4 to 5 times body weight in one study.
The power star jump is: it uses a quick dip and spring, as plyometric jumps do, so count each landing towards about 80 to 100 a session for beginners. Rhythmic jumping jacks are a gentler hop.
For power, 3 sets of 5 with about a minute's rest, twice a week. For cardio, 20 to 40 seconds at a time in intervals, building up from 1 or 2 rounds. Stop each set when your landings get loud.
Roughly 9 calories a minute of brisk jumping for a 70 kg person, by our arithmetic from a general reference value, so 100 calories takes about 11 minutes, not 100 jumps. Star jumps don't burn belly fat in particular: fat loss depends on your whole day's activity and food.
Yes: the NHS lists jumping among the activities that strengthen children's muscles and bones, alongside 60 minutes of activity a day. Jumping programmes have built children's bones in trials. Keep structured jump training for under-16s to sessions with a coach watching.
Not for healthy knees built up sensibly: they're two-footed jumps, and landing softly with your knees bent and over your toes shares the load. With sore knees, use step jacks, and keep pain to 0 to 2 out of 10, or up to 5 if it settles by the next morning.
Jumping raises the pressure in your tummy, and leaking with it is common: clinics use star jumps to test for it. It's treatable with pelvic floor exercises, ideally supervised for at least 3 months. Swap to step jacks meanwhile and see a GP or a pelvic health physiotherapist.
The NHS advises against starting new vigorous activity in pregnancy. If you already jump, stop when it causes leaking, heaviness or pelvic pain, and use step jacks. There's no evidence that star jumps bring on labour.
The NHS advises avoiding high-impact exercise to start with and getting advice at your 6-week check. UK guidance suggests waiting at least 3 months, until walking, hopping and jogging on the spot cause no leaking, heaviness or pain; that timing is expert opinion.
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.
