Power yoga: how hard it is, how it differs from vinyasa and Ashtanga, and how to start safely

Vigorous vinyasa

The British Wheel of Yoga (BWY) says "Power yoga is a form of vinyasa", and Bryan Kest, an Ashtanga-trained teacher who teaches under the name, says it "has now become a generic term usually used to describe a vigorous yoga class".

Sources 1, 2

Moderate on average

The Compendium of Physical Activities lists power yoga at 4.0 METs (metabolic equivalents: 1 is the energy you use sitting still), but marks that as an estimate. In 27 young adults, about 45 minutes kept heart rates mostly in the moderate and vigorous zones, and the US physical activity guidelines list active yoga such as vinyasa or power yoga as moderate activity.

Sources 3, 4, 5

Heart rate makes it look harder than it is

In yoga, heart rate rises more than energy use. A measured hour of vinyasa used less energy than a self-paced brisk walk.

Sources 6, 7

Calories: about 280 an hour, by our arithmetic

That's about 280 kcal (kilocalories) an hour for a 70 kg person, using the Compendium's estimate, against about 335 for brisk walking and 525 for jogging. It's a good workout, not the hardest.

Sources 3, 8, 9

Strength yes, bone not shown

The NHS counts yoga as muscle-strengthening, and a small trial of power yoga raised strength in people with Parkinson's disease. Yoga hasn't been shown to raise bone density.

Sources 10, 11, 12

The highest injury rate of the styles, on thin data

In a German survey, people who mainly did power yoga reported 1.50 injuries per 1,000 hours, against 0.60 for all yoga. That figure comes from 71 people reporting their own injuries, with a wide margin of error, and it is still below the published rate for running.

Source 13

A form of vinyasa

The BWY describes vinyasa as "a fluid form of yoga" that "can be quite athletic", and says "Power yoga is a form of vinyasa". Bryan Kest, who teaches under the name, says power yoga "has now become a generic term usually used to describe a vigorous yoga class".

Sources 1, 2

Where it comes from

A Wellcome Collection history of modern yoga says power yoga arose in the West in the 1990s from practitioners of Ashtanga and Sivananda yoga. Beryl Bender Birch's 1995 book Power Yoga taught Ashtanga's "rigorous series of positions that flow into one another in a prescribed order", and Kest studied Ashtanga in India with Pattabhi Jois.

Sources 14, 15, 16

How a class runs

Classes vary by teacher. A measured 60-minute power vinyasa class, based on a published sequence, ran from an opening sequence through sun salutations, crescent lunges, balances, standing poses and backbends to a restful close. A heart-rate study used about 45 minutes of power yoga.

Sources 17, 4

Heated classes

Some studios heat their power classes. Heat raises heart rate and body temperature but not the energy you use, as our hot yoga guide explains.

Source 18

An estimate, not a measurementStrong evidence

The 2024 Compendium of Physical Activities lists power yoga at 4.0 METs, printed in red, which it uses to mark estimated values rather than measured ones. That sits in the moderate range: the World Health Organization (WHO) counts 3 to under 6 METs as moderate and 6 or more as vigorous.

Sources 3, 19

Heart rate in a classEmerging evidence

In 27 adults with an average age of 23, about 45 minutes of power yoga kept heart rates in the moderate and vigorous zones for more of the time than in the light zone. They lost about 0.28 kg of body weight, mostly fluid.

Source 4

Measured flowsEmerging evidence

In 38 adults, an hour of vinyasa averaged 3.6 METs, against 4.4 for a self-paced brisk walk, though the first 45 minutes, before the restful close, used about as much energy as the walk. In a measured power vinyasa class, energy use and heart rate were lowest in the opening and closing sequences.

Pace matters: 8 minutes of sun salutation B at high speed used about 19 kcal more than at standard speed, and 10 minutes of fast sun salutations by yoga teachers averaged 8.7 METs, which is vigorous.

Sources 7, 17, 20, 21

Heart rate overstates the effortEmerging evidence

A review found that oxygen use usually classes yoga as light, while heart rate puts different styles in several bands. Across 17 energy studies, yoga sessions were mostly light, with sun salutations the main exception.

Sources 6, 22

Does it count toward the guidelines?Strong evidence

The US physical activity guidelines list "Active forms of yoga (for example, Vinyasa or power yoga)" among moderate-intensity activities, and say yoga can be both aerobic and muscle-strengthening, depending on the type and the poses. The NHS asks for 150 minutes of moderate activity a week, where you can still talk but not sing, plus strength work on 2 days, and lists yoga as muscle-strengthening.

Our reading: a power class counts as moderate activity and as a strength session.

Sources 5, 10

Not as hard as interval training or a circuit classStrong evidence

The Compendium puts vigorous circuit training at 7.5 METs, conditioning classes at 7.8 and high-intensity interval exercise at 7 to 11, and the US guidelines list high-intensity interval training (HIIT) as vigorous. Power yoga's estimated 4.0 is about half that. We found no trial that compared them head to head.

Sources 3, 5

An hour, for a 70 kg person

METs multiplied by your weight in kilograms gives the kcal used in an hour, including the energy you'd use sitting anyway. For 70 kg:

• Power yoga (the Compendium's estimate, 4.0 METs): about 280 kcal.
• Vinyasa (2.7 METs in the Compendium, 3.6 measured in a lab): about 190 to 250 kcal.
• Brisk walking (4.8 METs): about 335 kcal.
• Jogging, or a vigorous circuit class (7.5 METs): about 525 kcal.
• Running at 12 minutes a mile (8.5 METs): about 595 kcal.

Sources 3, 7, 8, 9

Weight lossMixed evidence

No controlled trial has tested power yoga for weight loss. In one uncontrolled pilot, 50 employees offered at least an hour of power yoga six mornings a week for 6 weeks, along with mindfulness and mindful-eating sessions, lost about 5 kg on average. With no comparison group and the eating sessions mixed in, it can't show what the yoga itself did. Our yoga for weight loss guide covers what helps.

Sources 23, 24

Ashtanga

Ashtanga repeats the same set series every time, with counted breaths. The one measurement, of a 56-minute beginners' Ashtanga video, averaged 2.5 METs, but that wasn't a full practice. Our Ashtanga yoga guide covers the series.

Sources 25, 26

Vinyasa

Vinyasa classes use the same breath-linked flow, in sequences each teacher designs. The Compendium lists vinyasa at 2.7 METs, and a lab study measured 3.6.

Sources 1, 3, 7

Power yoga

Power yoga is a form of vinyasa, usually more vigorous, with no set sequence; its 4.0 METs is an estimate. Our types of yoga guide compares all the main styles.

Sources 1, 17, 3

How much research there is

A large research database lists 3 papers with power yoga in the title and 12 that mention it in the title or summary, with 1 randomised trial. Most of what we know comes from studies of vinyasa and sun salutations.

Source 23

FitnessMixed evidence

We found no trial of power yoga as taught for heart and lung fitness. In 20 active adults, 4 weeks of fast-tempo "cardio yoga" raised fitness (VO2max, the most oxygen your body can use) more than the same yoga done more slowly. In 47 inactive young women, 8 weeks of 60-minute yoga sessions three times a week raised VO2max by about 12% against no exercise, as much as treadmill interval training did.

Sources 27, 28

StrengthEmerging evidence

In 34 women, 8 months of twice-weekly Ashtanga-based classes raised leg-press strength by 11%. In 26 people with mild to moderate Parkinson's disease, power yoga twice a week for 3 months reduced slowness and stiffness and raised strength on all five machines tested, against people who didn't do it. That was a pilot trial that needs repeating.

Sources 29, 11

BoneStrong evidence

Across 11 studies of Pilates or yoga in 591 women, bone density didn't change significantly, and 8 months of Ashtanga-based classes didn't change it either. For bone, our osteoporosis guide recommends strength and impact exercise.

Sources 12, 30

Mood and stressMixed evidence

After a single class, the stress hormone cortisol fell after both power yoga and stretch yoga in 33 women, who found the power class more pleasurable and energising. In 13 women, a 30-minute meditative yoga video lowered anxiety and cortisol, while a 30-minute power yoga video didn't. Across exercise trials for depression, benefits grew with intensity, and yoga helped more than control activities, on very low-certainty evidence.

Sources 31, 32, 33

HeatEmerging evidence

Across 43 hot yoga studies, heat raised body temperature and heart rate but not energy use, and the reviewers said claims of extra health benefits are, at present, unsubstantiated. In community classes, room temperature made no difference to the share of class spent at moderate intensity by heart rate.

Sources 18, 34

Does the style matter?Emerging evidence

Across 306 randomised yoga trials, positive conclusions were as common for one style as another.

Source 35

The highest injury rate of the styles, on thin dataMixed evidence

In a German survey of 1,702 practitioners, the 71 people who mainly did power yoga reported 1.50 sudden injuries per 1,000 hours, against 0.60 for all yoga; the margin of error ran from about 1 to 3 per 1,000 hours, and injuries were self-reported. Sudden problems were more common in people who mainly did power yoga than in other styles.

The authors note that the styles with the most problems put physical postures ahead of meditation or breathing. Yoga overall still had a lower injury rate than running or general fitness training (about 2.5 per 1,000 hours).

Source 13

More pain with vigorous yoga, in one trialEmerging evidence

In sedentary breast and ovarian cancer survivors, 40% reported mild to moderate pain with vigorous yoga, against 10% with restorative yoga.

Source 36

Muscle breakdown: one caseMixed evidence

A 36-year-old man developed compartment syndrome of the back muscles, with muscle breakdown (rhabdomyolysis), after a power yoga class. He was treated with rest, painkillers and fluids, and recovered fully within 6 months.

Source 37

What published cases of harm showMixed evidence

Reviews of published cases of harm name headstand, shoulder stand, lotus and forceful breathing most often, and a 2026 review found headstand the pose most often involved.

Sources 38, 39

GlaucomaEmerging evidence

The American Academy of Ophthalmology advises people with glaucoma to avoid strenuous inversions and to breathe out gently without holding the breath, and a yoga teacher in the same article suggests a slower style with props. In a lab study, downward dog raised eye pressure the most of four head-down poses. Use a wall or chair for downward dog, keep folds brief, and skip headstands.

Sources 40, 41

PregnancyStrong evidence

The NHS says it's not recommended to start a new vigorous activity in pregnancy, and the US National Center for Complementary and Integrative Health advises avoiding hot yoga in pregnancy because it can cause overheating. If you already practise, slow down and step rather than jump (our suggestion), and see our pregnancy yoga guide.

Sources 42, 43

OsteoporosisStrong evidence

Flowing classes fold forward many times. The UK consensus on exercise for osteoporosis advises modifying sustained, repeated or end-range forward bending, so fold from your hips with a long back.

Source 44

Heart conditions

Get advice before a fast or hot class if you have a heart condition, high blood pressure that isn't controlled, or have had a recent heart attack or operation.

Sources 45, 43

Your first few weeks

Our suggestions, drawing on the advice to learn with a qualified teacher and on the injury data:

• Learn sun salutations A and B first, in a beginners' or slow-flow class, or with our vinyasa flow for beginners.
• Then try a beginners' or level 1 power class, or our 40-minute workout.
• Step back rather than jumping, and lower with your knees down until a slow push-up is strong.
• Rest in downward dog or child's pose whenever your breath runs ahead of the movement.
• Try unheated classes first, and drink water.
• Leave headstands and arm balances until a teacher has taught you.

Sources 43, 13

How often

Two or three classes a week, with an easier day or a rest day after each (our editorial starting point; the Parkinson's trial used two a week). Keep 150 minutes of moderate aerobic activity across the week, such as brisk walking, cycling or running.

Sources 10, 11

Call 999

For chest pain that feels tight or like squeezing, or that spreads to your arms, neck or jaw, severe difficulty breathing, or if someone collapses. In the US, call 911.

Source 46

Heat illness in a hot class

Stop for dizziness, a headache, feeling sick, heavy sweating or cramps: get somewhere cool, drink and cool your skin. It should improve within 30 minutes. Call 999 if it doesn't, or for hot skin that isn't sweating, a fast heartbeat, fast breathing, confusion, a fit or passing out.

Source 47

Muscle breakdown after a hard class

Very sore, swollen or weak muscles with dark, red or cola-coloured pee, or peeing less than usual, after an unusually hard class need medical help the same day: call NHS 111, or go to A&E if you feel very unwell. It has happened after a power yoga class.

Sources 48, 37

Stop the pose

The NHS says to stop exercising straight away if you feel any pain or become unwell. Come out at once for sharp or increasing pain, tingling, numbness, dizziness or a sudden headache.

Source 45

Check first

Get advice before starting if you have a health problem, an injury or symptoms, have had a recent heart attack or operation, or are pregnant or have recently given birth. Tell your teacher about any condition.

Sources 45, 43

"Power yoga is as good a workout as HIIT or the gym"Strong evidence

Its estimated 4.0 METs is about half the 7.5 to 7.8 of vigorous circuit or conditioning classes, and the US guidelines list it as moderate, not vigorous. It is good strength work, but not a replacement for harder cardio.

Sources 3, 5, 10

"Power yoga burns as many calories as running"Strong evidence

About 280 kcal an hour at 70 kg, on an estimate, against about 525 for jogging and 595 for running at 12 minutes a mile.

Sources 3, 9

"A high heart rate means it's vigorous"Emerging evidence

Heart rate makes yoga look harder than oxygen use does, and a measured hour of vinyasa used less energy than a brisk walk.

Sources 6, 7

"Hot power yoga burns more and detoxes you"Emerging evidence

Heat raises heart rate and body temperature but not energy use, and we found no study of detox claims: the weight lost in a class is mostly fluid, about 0.28 kg in 45 minutes. Drink to replace it.

Sources 18, 4

"Power yoga strengthens your bones"Strong evidence

Yoga hasn't been shown to raise bone density, in trials of up to 8 months.

Sources 12, 30

"Power yoga is the same as Ashtanga"

Ashtanga repeats the same set series every time; power yoga is a form of vinyasa whose sequence changes with the teacher.

Sources 1, 25