Tracking Sarcopenia and Physical Activities Among Korean Adults Aged 50 Years and Older During COVID-19 Pandemic.

Only 50 of the original 97 participants were analysed; 29 could not be reached, 16 withdrew consent and 2 died, so the people who stayed in the study may differ from those who left. 88% of the participants were women, and the mean age was around 65, so these results may not describe men or the oldest patients. There was no control group and no sample size calculation. The study watched one group over time, so it cannot show that pandemic restrictions caused any of the changes rather than ageing or other factors. Physical activity was self-reported, so people may have misremembered how often or how long they exercised. Nutrition and food access were not measured at all, though the authors say these could have affected muscle mass. The rise in sarcopenia from 18% to 28% was not a significant difference, and the sample is too small for the subgroup analyses the authors say they would have liked to run.

The authors declare no conflicts of interest and state under funding that they have nothing to report. No industry sponsor or external funder is named.

Do not read this as proof that pandemic restrictions caused the decline. The same 50 people were followed over time with no comparison group, and 47 of the original 97 were lost to follow-up, so ageing or other unmeasured factors could explain the changes. The rise in sarcopenia from 18% to 28% was not a significant difference.