Introduction to Hot Yoga

Hot yoga is a type of yoga class where the room temperature and humidity are significantly increased. Typically, rooms for this type of class are heated to between 27°C and 41°C.

Some studios use humidifiers to increase and maintain relative humidity (the balance of heat to water vapour). Maintaining appropriate humidity alongside the room temperature helps create a comfortable environment, reduces excessive drying of the skin and airways, and supports the body’s natural ability to sweat effectively.

Origins and Evolution of Hot Yoga

Many teachers choose to work in warm rooms to ensure safety when moving the body into larger ranges of movement. During the winter, it would be reasonable to expect every yoga studio to be warmed by central heating or a similar system; a heated room in itself is nothing new. However, the concept of heating a room to high temperatures specifically for yoga classes is relatively recent, especially considering that yoga itself dates back thousands of years.

In 1970, while living and teaching in Japan, Bikram Choudhury began raising the temperature and humidity of his yoga practice room to resemble the warmer climate he had experienced in his native India. He believed that practising in a heated environment would increase muscle flexibility, enabling students to move more deeply into yoga postures. In 1973, he relocated to the USA and continued using the same approach while teaching in California. From there, the concept gained an international following.

Traditional Bikram Yoga consists of a fixed sequence of 26 asanas (poses) and 2 pranayama (breathing exercises) practised over a 90-minute class in a room heated to 41°C with approximately 40% humidity. Some participants find this relatively low humidity level can contribute to dry nasal passages and throat discomfort, causing them to cough.

The sequence originates from the teachings of Vishnu Ghosh, Choudhury’s teacher in Calcutta, India. During the mid-2010s, numerous allegations of sexual misconduct were made against Choudhury. Several cases were settled out of court, while others remained unresolved after he left the USA.

As a result, many studios that had previously associated themselves with Bikram Yoga chose to rename their classes as Hot Yoga, or to emphasise their connection to the original sequence through names such as Ghosh Yoga, Original Hot Yoga, or 26+2.

As studios adapted their timetables around the heating requirements of traditional hot yoga classes, many also began offering other heated styles, including Hot Vinyasa and Hot Yin. Unlike Original Hot Yoga, these classes generally do not follow a fixed sequence, allowing teachers to vary the content between sessions.

Typical Class Content

Traditional Bikram or Original Hot Yoga always follows the same sequence. Rather than being designed around flowing movement, the sequence alternates movement patterns and directions to provide a balanced practice.

By the end of the class, the spine will have moved through all six primary directions of movement: forwards/backwards, sideways (lateral flexion), right and left, rotation right and left.

The practice begins with Savasana (Corpse Pose) for approximately two minutes, allowing participants to acclimatise to the environment. Savasana is also repeated for 10–20 seconds between the standing and mat-based sections of the class, and between many of the mat-based postures, to allow the heart rate to settle.

The class includes an opening pranayama as a warm-up breathing exercise and a second pranayama at the end of the practice, accounting for the “+2” in 26+2.

There are a total of 26 postures:

• 12 standing postures
• 14 mat-based (seated or lying) postures, with seated upright positions frequently used as transitions and, in some cases, as postures in their own right.

The standing postures are generally held for 60 seconds during the first set and 30 seconds during the second. The first round serves as preparation, while the second is intended to maximise flexibility.

The seated postures are typically held for 20 seconds. Most, although not all, of the mat-based postures are also repeated twice.

Other forms of hot yoga, such as Hot Vinyasa and Hot Yin, generally follow the same structure as their non-heated equivalents.

Benefits of Hot Yoga

The heated environment warms the body and produces several physiological responses, many of which help regulate body temperature:

• Increased heart rate
• Increased breathing rate
• Increased vasodilation (widening of blood vessels) near the skin
• Increased muscle flexibility
• Increased sweat production

These responses may also contribute to a number of benefits:

• The increased heart rate and breathing rate create a more intense aerobic training benefit than might be expected from another form of yoga.
• The vasodilation of blood vessels near the skin, together with increased sweat production, cleanses the skin.
• Warm muscles allow for deeper stretches
• Warmth promotes relaxation during savasana.

In addition, breath control helps to regulate stress hormones such as cortisol. Regular yoga practice has also been associated with improvements in wellbeing and reductions in stress.

Hot Vinyasa classes are particularly demanding from a cardiovascular perspective, involving almost continuous movement throughout much of the practice.

Hot Yin classes, involving fewer postures held for longer periods, can provide a deeply relaxing experience, with the warmth encouraging greater comfort during prolonged stretches.

Safety Considerations and When to Exercise Caution

As with any form of exercise, the body adapts over time. Beginner classes are often held at around 27°C, while more advanced classes may use higher temperatures as participants become more accustomed to exercising in the heat.

The high temperatures are not suitable for everyone, particularly when compared with the UK’s typical climate. Some otherwise healthy individuals do not tolerate the heat well, and teachers should monitor new participants for signs of dizziness, heat intolerance, or heat exhaustion. The risk of fainting can be increased during rapid transitions between standing and floor-based postures, such as those found in Sun Salutations. Promptly recognising when a participant is struggling can help prevent more serious incidents.

Because of the additional demands that heat places on the cardiovascular and respiratory systems, hot yoga may not be appropriate for everyone. People with asthma, COPD, cardiovascular disease, high blood pressure, diabetes, those who are pregnant, or individuals taking medications that affect hydration or electrolyte balance should seek appropriate medical advice before participating.

The intense sweating experienced during class means that hydration should be carefully managed. Drinking water throughout the class is recommended, while electrolyte replacement may also be beneficial during prolonged or particularly intense sessions. Drinking large amounts during the initial warm-up is generally best avoided, allowing the body to begin adapting to the heated environment. Regular sipping throughout the main practice and adequate rehydration after class are important.

How Foundational Yoga Training Supports Specialisation in Hot Yoga

Unless following the traditional 26+2 sequence popularised as Bikram Yoga (now known under various names), virtually any style of yoga can be practised in a heated room. By understanding the physiological effects of yoga postures and the transitions between them, teachers can adapt their sequencing to maximise the potential benefits of a warmer environment.

Although teaching within the UK is unlikely to involve naturally occurring temperatures of 27–41°C (although climate change may make hotter conditions more common), understanding yoga in heated environments prepares teachers for practising and teaching in warmer climates around the world, including India, the birthplace of yoga. A recognised yoga teaching qualification is accepted in many countries, providing opportunities to teach while travelling.

Author

Sara Paul

Experienced Yoga and Fitness Professional

Sara has over 30 years' experience in the health and fitness industry, teaching classes in private and local authority facilities. She enjoys sharing her knowledge and skills in her role as a tutor, assessor and course developer. She has been involved in writing syllabus, manuals and assessments, including as the lead tutor to the Inclusive Fitness Initiative, working with disabled people, and through her work with frail older people. She co-created one of the first Yoga Teacher training courses within the fitness sector, having benefited from her own personal yoga practice.