When we breathe fine Particulate Matter (PM2.5) it's unhealthy. But so is not exercising. Has anyone studied the science of health rewards/risks for running when air pollution (pm2.5, ozone,...) is fairly high?
_____Has anyone tried running with an N95 mask? (the 95 is because with a "good fit" it filters out 95% of the small PM2.5 particles) N95 would be horrible for races, because it reduces air flow, but maybe for training? Would this be like "high altitude" training?
_____btw, I searched for "pm2.5" and "n95" but found nothing.
Post by chastennis on Dec 20, 2015 12:11:30 GMT -6
Some general information on aerosols.
Important points are that small respirable particles are important for health and difficult or impossible to see. Filtering this smaller particle size range is increasingly difficult as the particle size becomes smaller.
For the OP, a N100 mask is better than the N95 for the smaller particles. While this filter quality might be somewhat better, keep in mind that they still pass considerable respirable particles smaller than a certain size. The finer particle a filter stops the quicker its resistance to flow increases and the sooner it requires replacement.
Also the cheap, simple masks do not seal well and leak around the edges so that all particles may bypass the filter at the edges. A mask cannot work well with a poor edge seal. A mask with a rubber face piece can seal better against the face. Shaving must also affect this sealing.
Cutting grass produces a great quantity of respirable particles some of which come from the vacuum action of the lawn mower. You can see this dust especially when it is illuminated by sunlight and the background is the dark shade of the woods. In general, to best observe dust illuminate the dust with sunlight or a strong beam source and view against the darkest possible background.
One issue - small vacuum cleaners with simple screens as filters may remove visible particles, hair etc. but re-suspend a lot of respirable particles that can stay in the air of your home for days. In my opinion, those small vacuum cleaners with screen-like filters cannot filter particles in a healthy way and their use would increase exposure - possibly by a large amount. My grandson sometimes uses a dust vac type cleaner as a toy........
Another air quality issue is the profit model for current HEPA vacuum cleaners. The replacement filters are very expensive. I checked cost for a HEPA vacuum cleaner and the cost of its replacement filters and found them reasonable. I bought one. Now, two years later, when I went to purchase a 4" x 5 " HEPA exhaust filter I find that it cost $38 plus shipping! A 4" x 5" very ordinary looking filter! I view this as deceptive and a widespread practice and look forward to the first ethical vacuum cleaner manufacturer to offer a HEPA vacuum cleaner with reasonable costs for replacement filters and no price gouging.
I recall a news story from many years ago. One of the large Western cities that I had associated with having clean air developed one the the worst air qualities in the nation. An investigation was conducted. The large contributing source turned out to be simply the dust from unpaved farming roads generated from traffic.
Somehow I got asthma later in life so I am very attuned to this subject....
Last Edit: Dec 20, 2015 16:43:57 GMT -6 by chastennis
Post by Glenn Fleisig, Ph.D. on Dec 27, 2015 16:43:52 GMT -6
My wife is an allergist (treating allergy and asthma). When her athletic patients ask questions about this, she tells them to learn to play sports / physical activity breathing in through their nose and out through their mouth. Wearing a mask would be beneficial, but learning how to breathe in through the nose is practical and effective in many situations.
In late 2015, I asked about masks, and got good information -- thanks -- a useful review-of-masks from daque, tip from Glenn (breathe in thru nose, out thru mouth), and chastennis for info about principles (e.g. masks may not "seal well " so "particles may bypass the filter at the edges") and applications ("cutting grass" and "vacuum cleaners"). _____For more than a month recently, I've been exercising almost daily on an exercise bike while wearing a filtering mask: N95, 3M's model 8511. With the mask, I cannot ride as fast (RPMs are lower) or as long (usually I do "intervals" with 8 minutes of riding in 11 minutes, with two pauses, 1.5 minutes each, to recover) but my heart rate and breathing rate are high, as with mask-less exercising at higher RPM. I ride mornings, to get less of the ozone/O3 that is not filtered by N95 mask; the PMs (2.5 and 10) are fairly consistent throughout the day/night. _____The 8511 has an exhalation valve, which helps when I'm running outside, which I rarely do unless the PM-levels are lower than usual, which is rare in Southern California. In my next order from Amazon, I will buy another 10-box of 8511's, and also some cheaper valve-less masks to compare them (for exercising) with the 8511.
_____my questions: While exercising with the mask, there is much more re-breathing of CO2 than usual. If I consciously aim my outgoing breath through the exhale-valve, there is less CO2 buildup. So I'm wondering if, for general health benefits (I'm not training for a competition) including cardiovascular and more, it's better to have more CO2 re-breathing during exercise, or less? or to minimize CO2 by not using a mask? _____I've done a little web-searching, but not a lot. Searching for [exercise with filter mask co2] led to pages that were physiologically interesting, like www.normalbreathing.com/d/training-mask.php and, by a mask-seller, www.trainingmask.com/clinicals/using-co2-tolerance-to-improve-exercise-capacity/ _____But these are for a different kind of mask than the N95s from 3M. A more specific search [3m n95 mask exercise co2] was less useful for finding physiological information. _____Any information or useful thoughts will be appreciated.