Just because you perspire plenty during a hot yoga class doesn’t mean you’re detoxifying your body. (Thinkstock photo) More

What’s the hottest new workout taking the world by storm? That would be hot yoga, also known as Bikram yoga. Conducted in a heated room with sweltering temperatures of about 40°C (or approximately 104° Fahrenheit) and 40 per cent humidity, it’s guaranteed to make the body sweat… plenty! Hence, many believe this helps detoxify the body and burn major calories. But is it true?

Principal Physiotherapist Suelyn Chan from the Department of Physiotherapy at Singapore General Hospital (SGH), a member of the SingHealth group, tackles this and other burning myths of hot yoga.

Myths about hot yoga

Myth 1: Heavy sweating during hot yoga will help detox your body

Hot yoga can really make you sweat buckets -- up to two litres during a single session, according to reports. However, sweat is 99 per cent water combined with a small amount of minerals such as sodium, potassium and magnesium, as well as trace metals like zinc, copper and iron. Thus, sweating will mostly eliminate water and other constituents needed for bodily functions, says Ms Chan. Real toxins like mercury, alcohol and most drugs are eliminated by the liver, kidneys and intestines, not through sweat.

Myth 2: Exercising in a heated room elevates heart rate, offering a more intense workout

Raising the temperature of the room you’re exercising in does increase heart rate as your heart needs to work harder to cool your body down. But this does not mean that hot yoga puts greater physical demand on your muscles, hence offering a more intensive workout. Neither does it guarantee greater calorie burn or consumption. Heat by itself doesn’t burn calories.

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Myth 3: The heated environment warms up muscles so injuries are less likely to occur

It is true that heat enhances vasodilation of the blood vessels so more blood is delivered to the muscles, making muscles more elastic and less susceptible to injury. However, certain people are just generally less flexible than others. So even within a heated environment, advanced yoga postures might prove too difficult for a participant (especially if he or she rarely exercises) and continuous insistence of achieving these postures can still result in injuries to the legs and back.

Possible dangers of hot yoga

Apart from possible injuries arising from over-stretching, intense sweating also brings about the risk of heat exhaustion and dehydration. Furthermore, those not used to exercising in a hot and humid environment may experience sluggishness, dizziness or nausea during their first initial lessons.

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Ms Chan adds, “Patients with conditions such as multiple sclerosis, epilepsy and some cardiac complications can develop a unique sensitivity to heat. Plus, those taking medication for depression, nervousness and insomnia should also check with their doctor prior to participating in hot yoga to ensure the heat does not interplay with their medication.”

How to get your body ready for hot yoga

Most people need a minimum of two litres of fluid daily to stay hydrated. When doing hot yoga (or Bikram yoga), it is important to hydrate throughout the day rather than immediately before your class. This way, you won’t be bothered by a full bladder and will be able to concentrate fully on each yoga pose.

“You can bring a bottle of water with you and take sips during the class. After class, continue to rehydrate and supplement with electrolytes or an isotonic drink – replenishing minerals like sodium, potassium and magnesium, which were lost through sweat,” advises Ms Chan.

What are the benefits of hot yoga?

As with any form of exercise, there is always the risk of injury. However, regular practice of yoga has been proven to:

Elevate metabolism

Reduce stress

Build strength, endurance and muscle tone

Improve posture and circulation

Increase balance, coordination, focus and discipline

Strengthen the immune system

“When it comes to hot yoga, the key is to know your limits”, says Ms Chan. If halfway through a session, you feel lightheaded, dizzy or experience any discomfort, take a break or step out of the room. You should always listen to your body.

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