The exercise is to help your lungs function a little easier, like Jean said the meter only tells you your level of O2 in your blood. If you get up and move around and then take your reading you may find your O2 numbers down, which is normal but you can not let it get to low. The exercise is good for you, for it can help if you are struggle even while sitting it help control and relaxes the breathing. But as we all know what works for one or two may not work for all, I know this exercise works for me. I am right now at 12% lung function and on 3 liters of O2 24/7, I still exercise as much as I can but my O2 can not drop below 90% and my heart rate can not go higher than 129 bpm, if I exceed any of those numbers its off to the hospital for me. Listen to your doctors and do as they prescribe. I do keep a daily log of blood pressure, heart rate, O2, temperature, breathing treatments and when I take my medication. I take it along with me to all doctors appointments so my doctors know how I am doing in between my monthly visits. My kids also find it helpful to know when I am having a good day verses a bad one.

The bit that I forgot to mention is that I also have a Pulse Oximeter which must be used immediately before the lung exercise, record the reading, then again after. compare the two reading to see if the exercise is helping at all. If no change then seriously consider oxygen.

Des, your O2 saturation levels don't tell you whether the exercise is helping; they simply tell you what your O2 saturation level is after exercise. If your sat levels are down, then you should ask for a test to determine whether you're eligible for supplementary O2. The exercise will help whether your O2 levels go up, down or don't change at all.

I used to use three, Symbacord, forvent and duovent. The duovent was for emergency use only,
I also found it difficult to inhale. I was then changed to a Oxygen Concentrator, which supplies 70% oxygen and found that my Inhaling improved substantially. I also had to do lung exercises three times a day which also help quite a bit. The exercise recommended was to clench your fist and place the thumb side tight against the mouth, breath in through the nose to the count of 3 and breath out against the clenched fist to the count of 6. Repeat 10 times three times a day. The explanation given to me is that the fist encourages you to breath out using the diafram

Thanks everyone, these answers have helped a lot. Still waiting for rain to stop before walking but doing breathing exercises on and off during the day and arm stretching, all the normal.