Air pollution harms athlete airway and cardiovascular health
Fresh traffic and ice-resurfacer exhaust are the biggest concern; the performance evidence is thin
Key Findings
Short- and long-term inhalation of air pollution has well-documented unfavourable effects on the respiratory and cardiovascular systems.
Freshly generated mixed combustion emissions — near high-traffic roadways and from ice-resurfacing equipment — are of particular concern: whole fresh exhaust is more toxic than its component parts.
Emitted particles are considered to cause oxidative damage and inflammation in the airways and vasculature, and may be related to decreased exercise performance — but few studies have examined performance.
No research exists on long-term pollution exposure and athletic performance, and only a paucity of studies on acute exposure and exercise performance.
Inference, not tested: exercise raises minute ventilation and shifts to mouth breathing, so the inhaled dose during training is higher than at rest; the review does not give a multiplier.
Practical Application
The review's finding: pollution's respiratory and cardiovascular harm is well documented and fresh traffic/ice-rink exhaust is the sharpest hazard, while its effect on performance is plausible but barely studied — so manage exposure for airway health first, not for a proven watts-or-pace penalty.
Time/place training around pollution: avoid high-traffic roads and rush hour; on smoggy days move key aerobic work to cleaner air and cleaner hours (inference — ozone timing is not from this paper).
Use AQI/PM2.5 data (public-health AQI rule-of-thumb, NOT from this paper): ≤100 fine; ~100–150 move hard/long efforts indoors or shorten for sensitive/asthmatic; ≳150 indoors with filtration; wildfire smoke → cancel outdoor endurance.
Indoor isn't automatically clean (rinks with combustion resurfacers, gyms near garages); screen recurrent post-session cough/wheeze for EIB.
Limitations
Narrative review; no pooled effect sizes or validated athlete AQI cut-points (the thresholds above are public-health guidance); individual asthma/EIB susceptibility drives much of the response; performance effects largely unstudied per the review itself.
How this entry was checked and changed
Why this level
regraded 2026-09-27 from C: narrative review without systematic method (rubric C+)
Content correction 2026-09-27
"Exercise raises pollutant dose ~10–20× at rest" removed: not in the abstract; replaced by an unquantified inference.
Title/lead "impairs ... endurance performance" -> the abstract says performance effects "may" exist but few studies examined them and none on long-term exposure.
"elevated asthma/EIB near roadways and ice-rink skaters" -> the abstract flags roadway and ice-resurfacer emissions as of particular concern; EIB prevalence claims dropped. Level C -> C+; Tier "mixed" -> Tier 1-5.