I am 86 years old and for the past 40 years or so have been diagnosed with COPD. My height is 65 inches and weight 9 stone. My peak flow is usually about 260. It has been around this value for the past 40 years. I take 2 puffs a day of beclamethasone. I run twice a week over about 3 miles across country taking 1 puff of Ventolin before the start. It does not increase my peak flow noticeably. My breathing is very comfortable and I don't seem to get breathless until I come to a steep hill where I work hard to try to get my heart rate up to about around 140. I then go down the hill and back up again and push myself close to my limit to try to get my heart rate up to 145. occasionally I feel a bit lazy and peak at about 135 and finish my run hardly out of breath.
From what I have read my peak flow suggests I should be gasping for breath at just a moderate walk. Does anyone have any idea why my peak flow is low but my breathing is fine?