Effects of exercise training on obesity-related parameters in people with intellectual disabilities: systematic review and meta-analysis.

Most participants had Down syndrome (449 of the total), so the findings may not apply to people with other causes of intellectual disability such as autism, Prader-Willi syndrome, or fetal alcohol syndrome. Only 4 to 7 studies contributed to each outcome meta-analysis, which limits statistical power and means a true small effect could easily be missed. Thirteen of the 19 trials were rated fair quality on the PEDro scale. Only 5% blinded their participants, none blinded their therapists, and 21% concealed allocation. Different studies used different tools to measure body composition (bioelectrical impedance, dual-energy X-ray absorptiometry, skinfold calipers, formula-based estimates), which makes pooling less reliable. Studies that compared two different exercise programmes were excluded from the meta-analysis, so no direct comparison of exercise types is possible. The search was limited to English, French, Portuguese, and Spanish, and grey literature was not reviewed. Publication bias could not be ruled out.

The authors declare no funding for this research and no conflict of interest.

Do not read the aerobic-exercise BMI finding as proof that aerobic training works for weight loss in this population. It comes from pooling the same small number of trials in a different way, and the authors themselves say larger samples would be needed to confirm it. The main result across all exercise types was null, and the trials were small, mostly involved people with Down syndrome, and were largely unblinded.