Wearing masks has proven beneficial in preventing respiratory pathogen infections in individuals with chronic obstructive pulmonary disease (COPD). However, the impact of different mask types on physiological indicators and daily physical activity in COPD patients remains uncertain. This study aims to assess the immediate effects of various mask types on cardiopulmonary function indicators, subjective perceptions and the 6-minute walking distance (6MWD) in individuals with COPD.

This randomised controlled trial will enrol 129 stable COPD patients. Participants will be randomly divided into three groups: control, N95 mask and surgical mask groups. Each group will undergo both a 6-minute seated test and a 6-minute walk test (6MWT), without or with their respective masks. A 10-minute interval will be provided between the two phases. The primary indicators of the study include the 6MWD and blood oxygen saturation. Secondary outcomes encompass blood pressure, pulse rate, Borg score, Rate of Perceived Exertion (RPE) score and subjective perception score. Oxygen saturation, pulse rate and blood pressure will be recorded four times during the trial, while Borg and RPE scores will be compared before and after the 6MWT. Additionally, subjective perception scores will be collected after each mask-wearing stage.

This study has received approval from the Ethics Committee of the Affiliated Hospital of Gansu University of Chinese Medicine (approval number: 202335). We plan to disseminate research results through publication in a peer-reviewed journal or presentation at a conference.

ChiCTR2300074554.

Triglyceride glucose (TyG) represents a consistent surrogate biomarker and index of insulin resistance (IR), IR has also been linked to skeletal muscle mass loss (SMM-L). Here, we evaluated the association between SMM-L and the TyG index (TyGi).

An analytical cross-sectional study.

Tertiary care hospitals.

36 275 participants who underwent health checks between 1 January 2013 and 31 December 2020.

A bioelectrical impedance analysis was used to assess the body composition, SMM-L was defined as low ASMI (total limb lean mass/height²) and TyGi was calculated as ln(triglycerides (mg/dL)xfasting blood glucose (mg/dL)/2).

A total of 36 275 subjects were included in the study, of which 58.46% were male, with a mean age of 43.74±12.33 years. The prevalence of low skeletal muscle mass (SMM) was 17.7% and the mean TyGi was 8.56±0.64. TyGi was found to be significantly correlated with low SMM in all subjects (OR 1.87, 95% CI 1.75 to 2.00, p

These data demonstrated a significant independent interaction between TyGi and low SMM in all subjects regardless of sex and age subgroups in the general population.