PM2.5 was significantly associated with a reduction in both the proportion of deep sleep and next-day long-distance running performance, with its negative association with running performance exacerbated by high CO2 levels (3,961 ppm) during sleep.
Key Findings
Results
Bedroom PM2.5 exposure was significantly associated with a reduction in the proportion of deep sleep among young adults.
Study conducted among 183 young adults with continuous monitoring of bedroom environment and sleep quality.
Sleep quality was continuously monitored during the night prior to standardized physical fitness testing.
Multiple linear regression was used to analyze the association between bedroom PM2.5 and deep sleep proportion.
Deep sleep proportion was used as an objective measure of sleep quality in the analysis.
Results
Bedroom PM2.5 exposure was significantly associated with reduced next-day long-distance running performance.
Physical performance was evaluated using a standardized physical fitness test that objectively assessed participants.
Long-distance running test was the specific physical performance measure negatively associated with PM2.5.
The study sample consisted of 183 young adults.
Multiple linear regression was used to analyze the association between bedroom PM2.5 and next-day running performance.
Results
The negative association between PM2.5 and long-distance running performance was exacerbated by high CO2 levels during sleep.
The interaction effect was identified at a CO2 level of 3,961 ppm during sleep.
Interaction effects of environmental factors were examined using multiple linear regression.
Both PM2.5 and CO2 were continuously monitored in participants' bedrooms.
This finding suggests a combined adverse effect of particulate matter and elevated CO2 on next-day physical performance.
Methods
This field study monitored bedroom environmental conditions and sleep quality continuously in the night prior to standardized physical fitness assessment.
183 young adults participated in the study.
Participants were required to undergo standardized physical fitness tests that objectively evaluated their physical performance.
Bedroom environment monitoring included at least PM2.5 and CO2 levels.
Sleep quality was continuously monitored during the same night preceding the fitness assessment.
What This Means
This research suggests that the air quality in a person's bedroom while they sleep can meaningfully affect both how well they sleep and how they physically perform the next day. The study tracked 183 young adults, measuring the levels of fine particulate matter (PM2.5) and carbon dioxide (CO2) in their bedrooms overnight, while also monitoring their sleep. The following day, participants completed standardized physical fitness tests. Higher levels of bedroom PM2.5 were linked to less deep sleep and worse performance on a long-distance running test.
The study also found that elevated CO2 levels in the bedroom made the negative effect of PM2.5 on running performance even worse. Specifically, when CO2 reached around 3,961 ppm — a level that can occur in poorly ventilated rooms — the harmful association between particulate matter and next-day running performance was amplified. This suggests that having multiple air quality problems at once in a sleeping environment may compound their individual harmful effects.
This research suggests that maintaining clean, well-ventilated bedroom environments — keeping both fine particle pollution and CO2 at low levels — may be important not only for good sleep but also for physical health and performance the following day. For young people especially, paying attention to bedroom ventilation and indoor air quality could have practical benefits for their day-to-day physical capabilities.
Lin X, Ji T, Guo R, Guo C, Gong P, Lan L. (2026). Association of bedroom particulate matter, sleep quality and next-day physical performance.. Scientific reports. https://doi.org/10.1038/s41598-026-37949-2