Yoga guide
Yoga works your core more than its calm reputation suggests. In small lab studies, boat pose worked the front tummy muscles hardest of 16 poses, with plank next, and downward dog worked the side tummy muscles about as hard as a forearm plank. In a 3-month study, twice-weekly hatha classes with trunk work lengthened how long people could hold trunk-muscle tests by 15% to 50%.
What it builds is mostly endurance and control rather than maximal strength, and it won't burn belly fat or replace pelvic floor exercises.
This guide covers what the core is, what the muscle studies and trials show, back pain, bracing, belly fat and the pelvic floor, how to make each pose harder, with a 3D demo of every pose, and a free 20-minute class.
In small lab studies, boat pose and plank worked the front tummy muscles hardest of the poses tested, and downward dog worked the side tummy muscles about as hard as a forearm plank. In a 3-month study, hatha classes with trunk work lengthened trunk-muscle hold times, which is endurance more than maximal strength.
Yoga eased long-lasting low back pain a little compared with no exercise, and about as much as other back exercise. Exercises aimed at the deep core muscles were no better than other exercise.
Firming the whole trunk steadied the spine more than pulling the belly button in. "Navel to spine" is a cue, not a rule.
Six weeks of daily ab exercises didn't change belly fat, and 13 studies found no local fat loss from training one area. Losing fat is about your whole week, as our yoga for weight loss guide explains.
A 12-week pelvic yoga programme reduced leaks no more than a general exercise programme. If you leak, do pelvic floor exercises every day.
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One review says there is "less clarity about what exactly constitutes 'the core'", and defines core stability as "the ability to control the position and motion of the trunk over the pelvis". Another calls the research behind core training "meager". In practice the word covers the tummy muscles, the back muscles and the hips, with the diaphragm above and the pelvic floor below.
Lab studies use electromyography (EMG): sensors on the skin record a muscle's activity as a percentage of its strongest contraction. A rule of thumb from rehabilitation research says that above about 45% may build strength, and below it builds endurance and control. Studies measure the maximum in different ways, so a dolphin plank can read above 100%, and poses should be compared only within the same study.
Most yoga poses are held, so they train how long your trunk can hold a position more than how much force it can make. Trials measure this with timed holds: in 75 healthy young adults, men held a side bridge about 65% as long as a back-extension hold, and women about 39% as long.
Yoga's "locks" include mula bandha (a pelvic floor lift) and uddiyana bandha (drawing the belly in and up after breathing out). They're often described as core training, but we found no study that measured their effect on core strength or trunk muscles. In 30 students, uddiyana bandha raised diastolic blood pressure straight afterwards; it was back to normal within 10 minutes.
These are small lab studies that measured different muscles in different ways, so compare poses only within each study.
In 22 trained practitioners, boat pose worked the front tummy muscles above half of their maximum and plank about a third, while cat-camel, camel, downward dog and the warrior poses stayed under a fifth. Of four poses in another study, plank worked the six-pack muscle and the obliques most, and in a third, high plank, low plank and downward dog worked the outer obliques most of 11 poses.
In 14 men, downward dog worked the obliques and the front hip muscles about as hard as a forearm plank. A dolphin plank was the hardest of three poses for the tummy and back muscles in a fifth study.
Reverse boat, a face-down chest and leg lift, worked the back muscles harder (41.7% of maximum) than bow pose, cobra and the warrior poses in the 16-pose study, and chair pose worked the lower back muscles most of four poses in another. Of five poses, half moon and warrior III worked the glutes hardest, and locust thickened the deep back muscles on ultrasound.
In one study, locust activated the pelvic floor far more than a front plank (63.5% against 26.3% of maximum), with side angle and side plank in between.
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In sun salutations, every muscle measured was more active while moving between poses than while holding them, and a faster flow worked the muscles harder overall.
In general exercise studies, the side bridge and the arm-and-leg lift on all fours reached the rule-of-thumb strengthening range for some hip and trunk muscles, and free-weight lifts such as squats and deadlifts worked the tummy and back muscles hardest of all. Yoga poses weren't part of those comparisons.
In 72 healthy adults who chose to join, 25 hour-long hatha classes with trunk stabilisation work over 3 months lengthened a front trunk hold by 90.8 seconds (52.5%), against 13.6 seconds in a matched group, and a back hold by 48.9 seconds, against a fall of 9.6; side holds improved clearly on one side only. Results varied widely from person to person.
In young women, 10 weekly beginner classes raised plank time from 79 to 99 seconds, with no comparison data. A 21-day yoga course and a 3-month yoga-based programme also improved core measures, without randomised comparison groups.
Randomised trials in 40 junior tennis players, 82 cricketers and 20 fencers found better scores on core stability and movement tests after yoga. They used sport-style tests rather than core strength itself, and in the tennis players core strength rose in the comparison group too.
We found no trial that compared core strength between yoga and Pilates. In the fencers, both improved a movement screen.
In 21 trials (2,223 people), yoga reduced pain by about 4.5 points out of 100 and improved function a little at 3 months compared with no exercise, less than the amount people usually notice, and it did about as well as other back exercise. More back pain was the commonest side effect.
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Exercises aimed at the deep core muscles, called motor control or stabilisation exercise, did no better than other exercise in two reviews of 29 studies each, and exercise in general reduced back pain across 249 trials. Choose the exercise you'll keep doing; our yoga for back pain guide has a gentle sequence.
In a lab and modelling study of 8 men, bracing the whole trunk gave 32% more spine stability than hollowing (drawing the belly button in), and the deepest tummy muscle added 0.14% of the brace's stability. In another small study, hollowing didn't steady the spine against sudden loads, and in a review of 15 studies, changes in the deep muscles didn't explain recovery from back pain.
Keep breathing, keep your ribs and pelvis steady, and firm your middle as if expecting a gentle poke. "Draw your navel in" is a cue some people like, not a rule; our Pilates core guide says the same.
Six weeks of abdominal exercise, 5 days a week, didn't change belly fat or waist size in 24 adults, though they managed more curl-ups. A review of 13 studies of training one limb found no local fat loss. One trial in 16 men found slightly more trunk fat lost (697 g) when tummy exercises were added to running, with the same total fat loss.
In 60 women with abdominal obesity, 12 weeks of yoga reduced waist size by 3.8 cm compared with a waiting list. That was the whole programme, about 30 hours of yoga, not toning one area: our yoga for weight loss guide covers it.
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Locust strongly activated the pelvic floor in a lab study, but in 240 women aged 45 to 90 who leaked every day, 12 weeks of pelvic yoga reduced leaks by 2.3 a day against 1.9 with a general exercise programme: no clear difference. If you leak, do pelvic floor exercises every day, and see a GP or pelvic health physiotherapist if it isn't improving.
We found no study of the bandhas and core strength. Uddiyana bandha briefly raised diastolic blood pressure, so skip it if you have high blood pressure.
The trunk endurance study used two classes a week, and the NHS asks for muscle-strengthening on at least 2 days a week. Our editorial starting point: our 20-minute class twice a week.
For planks, 3 holds of 20 to 45 seconds is plenty, ending each one when your hips sag or your back arches (our plank guide). Once 30 seconds feels easy, make the pose harder rather than longer.
Lengthen the lever (straighter legs in boat pose, a full plank instead of a knee plank), lift a limb (three-legged dog, a side plank with a leg lift), and move slowly between poses, which worked the muscles harder than holding in lab studies. A long-lever plank with the pelvis tucked under worked the tummy harder than a standard plank in one.
Keep breathing through every hold. With high blood pressure, don't strain, as the plank pages say.
Straight-arm plank: 3 holds of 15 to 30 seconds (the move's page). Knee and forearm planks: up to 3 holds of 20 to 45 seconds (our plank guide). Knee side plank: 15 to 20 seconds each side, as in our beginner core workout, before the full side plank. Boat pose: 3 holds of 3 to 5 breaths with your knees bent, and plank-to-dog waves: 5 slow ones (our editorial starting points). Keep head-down time short in dog and dolphin with glaucoma or uncontrolled high blood pressure.
3D demoKnee plankBeginner · No equipment
3D demoForearm plankIntermediate · No equipment
3D demoStraight-arm plank (high plank)Intermediate · No equipment
3D demoDownward-facing dog (Adho Mukha Svanasana)Beginner · No equipment
3D demoKnee side plankBeginner · No equipment
3D demoSide plankIntermediate · No equipment
3D demoBoat pose (Navasana)Intermediate · No equipment
3D demoDolphin pose (Ardha Pincha Mayurasana)Intermediate · No equipmentBird dog: 6 each side, as in our beginner core workout, holding 3 to 5 seconds. Locust: 3 lifts held for 3 to 5 breaths; bridges: 10 slow lifts; chair pose: 2 holds of 5 breaths; warrior III and half moon: 3 to 5 breaths each side, by a wall (our editorial starting points).
3D demoBird dogBeginner · No equipment
3D demoLocust pose (Salabhasana)Beginner · No equipment
3D demoGlute bridgeBeginner · No equipment
3D demoChair pose (Utkatasana)Beginner · No equipment
3D demoWarrior III (Virabhadrasana III)Advanced · No equipment
3D demoHalf moon pose (Ardha Chandrasana)Advanced · A stepCat-cow for 8 slow waves, slow breathing for at least 5 minutes and corpse pose for 5 to 10 minutes (the moves' pages). Pelvic floor exercises: start with 8 slow holds of up to 10 seconds and 8 quick squeezes, three times a day (the move's page). The lying twist: 45 seconds each side (editorial).
In lab studies, moving between poses worked the muscles harder than holding them, and downward dog worked the obliques about as hard as a forearm plank. Five waves is our editorial starting point.
See the movement on the 3D figure: Downward-facing dog (Adho Mukha Svanasana)
Start with our 20-minute yoga for core class twice a week (our editorial starting point). The beginner core workout and the McGill routine add non-yoga moves; the pelvic floor routine is the one for leaks.
Twenty minutes of plank, side plank, boat pose, back lifts and standing balances: the yoga poses that work the trunk hardest, with easier and harder options.
20 minBeginner13 movesNo equipmentA 15-minute beginner core workout on the floor: dead bugs, bird dogs, knee planks, side planks and curl-ups.
15 minBeginner6 movesNo equipmentThe McGill big three for the core: curl-ups, side planks and bird dogs, each held for 10 seconds at a time in falling sets of 5, 3 and 1 reps.
12 minBeginner3 movesNo equipmentA 12-minute plank session for the 30-day plank challenge: front planks that get harder, not longer, plus side planks and bird dogs for the whole trunk.
12 minBeginner12 movesNo equipmentAn intermediate ab workout with no equipment: planks, side planks, reverse crunches, hollow holds and mountain climbers.
20 minIntermediate7 movesNo equipmentA 25-minute beginner session pairing each Pilates move with its yoga cousin: Pilates moves through repetitions, yoga holds the pose with the breath.
25 minBeginner16 movesNo equipmentA 40-minute power yoga workout: sun salutations, lunges, strength holds, balances, core work and backbends, moving with the breath, then a rest.
40 minIntermediate18 movesA stepA 5-minute daily pelvic floor workout for women and men: slow holds and quick squeezes, three times a day, with how to find the right muscles.
5 minBeginner2 movesNo equipmentA month of gradually longer and harder planks.
These are the same warning signs as our Pilates core guide. A&E means accident and emergency. In the US, call 911 for 999, and contact your doctor or urgent care for NHS 111.
If back pain comes with pain, tingling, weakness or numbness in both legs; loss of feeling around your genitals or anus; changes in your bladder or bowels; or chest pain; or if it started after a serious accident.
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For a bulge in your groin or tummy that is painful, or comes with a swollen tummy, being sick or constipation, as our guide to exercise for men explains.
For leaking, a dragging or bulging feeling in the vagina, pelvic pain or pain during sex. After a birth, follow our postpartum guide on when to see a GP about a tummy gap.
Stop for chest pain or pressure, unusual breathlessness, dizziness or fainting. Call 999 for chest pain that comes on suddenly and doesn't go away, or spreads to your arms, neck, jaw, stomach or back.
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Boat pose's page says to avoid it in pregnancy and after recent tummy surgery. The plank pages say that in the first weeks after giving birth the NHS advises avoiding sit-ups and planks to start with, and to avoid planks with heart failure. Face-down poses get uncomfortable as a bump grows: bird dog on all fours works instead.
Exercising one area doesn't burn the fat over it: 6 weeks of daily ab exercises changed no fat measure, and 13 studies found no local fat loss. Whole yoga programmes can reduce waist size a little, as part of the whole week.
In small lab studies, boat pose and plank worked the front tummy muscles hard, and downward dog worked the obliques as hard as a forearm plank. Twice-weekly classes lengthened trunk hold times in a 3-month study.
Bracing the whole trunk steadied the spine more than hollowing in small lab studies, and changes in the deepest tummy muscle don't explain recovery from back pain. It's a cue, not a rule.
Yoga helps back pain a little, about as much as other back exercise, and exercises aimed at the deep core muscles do no better than other exercise.
We found no study that measured their effect on core strength; the review that promoted them as core training gave no data, and uddiyana bandha briefly raises blood pressure.
Our plank guide suggests 3 holds of 20 to 45 seconds and says longer isn't better. To keep progressing, make the plank harder: a longer lever worked the tummy harder in a lab study.
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Yes, mostly its endurance. In small lab studies, boat pose and plank worked the front tummy muscles hard, and in a 3-month study, twice-weekly hatha classes with trunk work lengthened trunk-muscle hold times by 15% to 50%. Most poses train holding power rather than maximal strength.
Boat pose, plank, side plank, downward dog and dolphin plank for the front and sides, and locust, chair pose, warrior III and half moon for the back and hips. A slow wave from plank to downward dog adds work, because moving between poses works the muscles harder than holding them.
No trial has compared them for core strength. Pilates focuses on the trunk more of the time, while yoga mixes core work with standing strength and balance, so choose the one you enjoy and will keep doing.
Yoga strengthens the tummy muscles, but whether they show depends on body fat, which ab exercise doesn't burn locally. Our how to get abs and yoga for weight loss guides cover what changes body fat.
No exercise burns the fat over the muscle you're working: 13 studies found no local fat loss. A 12-week yoga programme reduced waist size by 3.8 cm in women with abdominal obesity, as a whole programme rather than by toning.
Three holds of 20 to 45 seconds is plenty, ending each one when your hips sag or your back arches. When 30 seconds feels easy, make the pose harder rather than longer, with straighter legs or a lifted limb.
Yoga usually uses a high plank on straight arms, while the gym plank is usually on the forearms. In one small study, the forearm plank and downward dog worked the obliques harder than a high plank. High plank loads the wrists, so use your forearms or fists if they hurt.
You don't need to. Bracing the whole trunk steadied the spine more than drawing the navel in, and the deep muscle that hollowing targets doesn't explain recovery from back pain. Keep breathing and keep your middle firm and still.
It helps a little: in 21 trials, yoga lowered pain by about 4.5 points out of 100 compared with no exercise, and did about as well as other back exercise. Exercises aimed at the deep core muscles weren't better than other exercise; our yoga for back pain guide has a gentle sequence.
Locust activated the pelvic floor strongly in one lab study, but in 240 women who leaked daily, a pelvic yoga programme didn't beat a general exercise programme. If you leak, do daily pelvic floor exercises, and see a GP or pelvic health physiotherapist if it isn't improving.
Twice a week is a good start: the study that improved trunk endurance used two classes a week, and the NHS asks for strength work on at least 2 days. Keep sessions short and make the poses harder rather than longer.
Boat pose isn't advised in pregnancy, and face-down poses get uncomfortable as your bump grows, so use all-fours moves like bird dog instead. In the first weeks after giving birth, the NHS advises avoiding sit-ups and planks to start with; our postpartum guide explains how to build up.
Exercise education, not a personal prescription, and clinical review of these guides is pending. If you are pregnant, have a health condition such as glaucoma, high blood pressure or osteoporosis, or have had recent surgery, check with a doctor, midwife or physiotherapist before starting, and stop for sharp or increasing pain. Health disclaimer.
