Performing high-intensity yoga twice a week is the most effective exercise regimen to improve sleep quality, according to a new review of studies.
Exercise is known to improve sleep disorders, but the best type of workout to prescribe for those who struggle with sleep has been a topic of debate.
A new research review compared the effects of different exercise regimens on the sleep quality of people with sleep disorders, providing strong evidence for effective intervention programmes.
Scientists from Harbin Sport University in China assessed data from 30 individual clinical trials involving 2,576 participants across all age groups.
They compared the effects of different workouts including yoga, walking, resistance training and traditional Chinese practices like qi gong and tai chi.
The findings, published in the journal Sleep and Biological Rhythms, reveal that high-intensity yoga offers the best sleep improvement.
“The results of the network meta-analysis show that the optimal exercise prescription combination is yoga with a frequency of twice a week, a duration of about 30 minutes, lasting 8 to 10 weeks, and performed at high intensity,” scientists wrote.
Walking was the next best physical activity for sleep improvement, followed by resistance exercise, with benefits seen within 8 to 10 weeks, the study suggests.
The study falls short of explaining why yoga could be the most beneficial among different exercise types.
Previous studies hint that apart from increasing heart rate, yoga may also activate the parasympathetic nervous system, which controls the body’s digestion and rest.
The scientists called for more review studies, including a greater body of data, to confirm their findings.
"Caution should be exercised when interpreting findings from studies on sleep disturbances, given the limited number of studies included and the unique characteristics of the sleep disturbances population," they wrote.
A review of 25 studies published in April hinted that strength training could be the best for insomnia in older adults, more than aerobic or combined workouts.
Previous research also indicates that, whichever the chosen discipline, all forms of high-intensity workout are best completed well before bedtime.
A recent study of over 14,000 participants found that exercising even up to four hours before going to bed can affect sleep quality.
For instance, a full-intensity workout ending about two hours before bedtime can delay the onset of sleep by over 30 minutes and reduce overall sleep duration by more than 20 minutes, according to the study published in Nature Communications.
The findings of this study suggest that any exercise completed four hours before habitual bedtime was safe, with no negative impact observed on sleep patterns.
