Tai chi "ranked best" for depression in older adults. It didn't beat anything.

A network meta-analysis of 23 trials and 1,485 older adults ranked Tai Chi first for depressive symptoms (SUCRA 83.3%). But every head-to-head comparison between exercise types was statistically non-significant, with intervals as wide as -7.02 to 6.00.

Mind-body exercise is an appealing option for depression in later life: low intensity, little equipment, no drug interactions. The open question is whether the particular practice matters, so researchers led by Zaiwen Wang ran a network meta-analysis -- a method that can compare treatments never tested against each other by linking them through shared comparisons -- across 23 randomised trials covering 728 older adults in intervention groups and 757 in control groups, all averaging over 63 years old. The rankings that came out are the part likely to be quoted: Tai Chi first with a SUCRA of 83.3%, then Pilates, Yoga, Qigong and Square Dancing. Read the comparisons underneath and the ranking dissolves. Tai Chi versus Pilates gave a standardised mean difference of -0.51 with a confidence interval from -7.02 to 6.00. Against Yoga, -1.22 (-5.87 to 3.42). Against Qigong, -1.81 (-5.84 to 2.22). Every interval crosses zero, several by an enormous margin, meaning the data cannot distinguish these practices from one another at all. The only statistically significant finding in the network was Qigong against no intervention (-4.00, -7.32 to -0.68). A SUCRA value is a probability of ranking highly, not a measure of how much better something is, and the authors say so directly, warning that their network was unbalanced and sparse and that the results show "estimated trends and uncertainty rather than definitive superiority." One further limitation is unusually consequential here and the authors flag it themselves: the review searched only English-language databases, excluding Chinese ones, while three of the five interventions compared -- Tai Chi, Qigong and Square Dancing -- are practices whose trials are disproportionately published in Chinese. The defensible takeaway is that gentle group exercise beats doing nothing, and that picking between the types is not yet supported by evidence.