How much research there is
A search of a large research database found 12 records with restorative yoga in the title and 17 more that mention it in the summary. Every study of restorative yoga alone is small, from 14 to 180 people, and only one compared it with an equally attentive class over a year.
Sources 21, 1
StressMixed evidence
In 20 night-shift nurses in Japan, 4 weeks of restorative poses at home, for about 5 to 15 minutes at least 3 times a week, lowered work-stress scores from 65.7 to 56.1, against 64.1 with their usual ways of relaxing. No one dropped out.
But in the year-long trial in adults with the metabolic syndrome, the stretching class lowered perceived stress (by 2.0 points more at a year) and cortisol (at 6 months) more than restorative yoga did. The authors credit the group support of the more interactive stretching classes. A study of 25 medical students, who felt more relaxed after weekly classes, had no comparison group.
Sources 4, 5, 22
Blood sugar and the metabolic syndromeEmerging evidence
The metabolic syndrome is a cluster of raised blood pressure, blood sugar, blood fats and waist size. In 180 underactive adults with it, 48 weeks of restorative yoga lowered fasting blood sugar by 0.35 millimoles per litre, against 0.03 with stretching. Nothing else differed: not long-term blood sugar, blood fats, insulin, blood pressure or belly fat. The authors call restorative yoga marginally better than stretching for fasting glucose. An earlier pilot in 26 adults found a trend toward lower blood pressure that wasn't significant.
Sources 1, 23
Mood in cancerMixed evidence
In small studies of women with breast or ovarian cancer (33 to 51 people), restorative classes improved depression, mental health or positive mood, against a waiting list or with no comparison group. Results for tiredness and sleep were inconsistent.
Sources 24, 25, 26
Gentler than vigorous yoga, and easier to keep upEmerging evidence
In 35 sedentary breast and ovarian cancer survivors, restorative yoga three times a week was compared with vigorous, vinyasa-based yoga. More people kept going with restorative yoga (85% against 73% attended enough classes), fewer reported mild to moderate pain (10% against 40%), and thinking skills were better at 24 weeks. Most people who were asked declined to take part (175 of 226), so the volunteers may not represent everyone.
Sources 27, 28
Cancer guidelines on yogaStrong evidence
US cancer guidelines from the American Society of Clinical Oncology (ASCO) and the Society for Integrative Oncology say yoga may also be recommended for tiredness after cancer treatment, and recommend yoga for anxiety during treatment and for low mood during and after it. They mean yoga in general, not restorative yoga in particular. Our exercise and cancer guide has more.
Sources 29, 30
Sleep: one large trial of a combined programmeEmerging evidence
In 410 cancer survivors with poor sleep, 4 weeks of twice-weekly 75-minute classes mixing gentle hatha and restorative poses improved sleep quality more than usual care, and sleeping-pill use fell by 21% a week, against a 5% rise. There was no comparison class to match the attention, and the two styles can't be separated. We found no trial of restorative yoga alone for sleep.
Sources 15, 21
Sticking with itEmerging evidence
In the year-long trial, people attended more restorative classes than stretching classes (67% against 52%) and did more home practice in the first 6 months (85% against 67%), and in cancer survivors more people kept going with restorative than with vigorous yoga. That matters most for people who are exhausted, unwell, older or new to exercise (our reading).
Sources 1, 27
WeightEmerging evidence
In 50 adults with obesity on a 6-month diet and behaviour programme, those who added restorative hatha yoga lost about as much weight as those who added vinyasa (3.4 against 3.8 kg). The diet did the work, and nearly half found the hour-long sessions a barrier.
Source 7
Hot flushesMixed evidence
In 14 women after the menopause, 8 weekly 90-minute classes cut hot flushes by about 31% a week, with no comparison group and no harms reported. Our exercise and menopause guide covers the options with better evidence.
Source 31
What it can't promiseMixed evidence
The method's school says restorative yoga activates the calming (parasympathetic) branch of the nervous system and may lower blood pressure and improve fertility, immunity and digestion. No restorative trial we found has tested these. In the nurses, blood pressure and pulse fell a little over a session but not significantly, and in the year-long trial cortisol fell more with stretching.
Sources 2, 21, 4, 5