For thousands of years, yoga has been practiced as a tonic for body, mind and spirit. This ancient discipline encourages relaxation through controlled breathing, meditation and striking various body poses.

In recent decades, yoga has become increasingly popular in the United States. But is yoga really a form of exercise?

Experts say the answer is "yes."

Mind and Spirit

Yoga is an excellent form of exercise for the mind and spirit. The deep breathing and meditation of hatha yoga (widely considered to be the most popular form of yoga in the United States) help you relax.

People who practice hatha yoga learn up to 30 poses or more, in varying degrees of complexity. Practitioners also learn to control their breathing. The concentration required during a yoga session helps take your mind away from daily stresses.

As a result, practicing yoga may help you sleep better. You may also develop more effective coping skills and a more optimistic outlook.

A recent Boston University study found that one hour of yoga boosts levels of gamma-aminobutyric, a neurotransmitter that helps reduce anxiety and depression. Researchers concluded that combining yoga with other treatments (such as medication and psychotherapy) may promote emotional stability.

Physical Benefits

Yoga is also good exercise for the body. Many of the poses associated with yoga require great physical flexibility. Even basic poses require you to stretch muscles, which increases your overall range of motion. This increased flexibility makes you less vulnerable to injury.