Medical fail low peak flow


Hey everyone pretty new here but I'll just keep this simple. Basically I went for my first medical in November 2015 and failed due to my peak flow reading being around about 450 which I understand is low for me (age 19 ). When told about the failure she said that everything else was perfect but due to the low reading I would fail and have a re medical in June 2016. I have never had asthma in my life and never had any breathing difficulties. I've been training since December now and can't seem to get my peak flow about 450 and need any suggestions on what would work effectively other than running and swimming. If I was to ring my GP and go for a lung cuntion test and a spirometry test and they came back good would this help my cause for my second medical if my peak flow was low?
I'm obviously not a doctor, but having done those tests before:

1. You have a hidden issue
2. Practice more. When I did it, I do believe it can be a technique thing. I've had 450-500, changed my technique and got 550 (5ft 11). Big breath, and blew on the edge ( :oops: ), helped me get a 'good' score.
Technique can definitely be a cause for a low peak flow, try and get your own off your GP or somewhere so you can practice at home. Try checking a few guides online for technique. I had asthma as a child but have an average reading of 800 and I'm 22 and 6'2
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War Hero
Sorry to hear of your circumstances. Anecdotally, I've heard applicants claim their low reading was due to poor technique rather than poor lung function as the peak flow meter is not a wholly accurate measures of lung function. Again, I'm not medically qualified but it is a recurrent claim I've heard over the years.

To a degree, any supporting medical evidence such as an independent pulmonary lung function test may well help in achieving a positive outcome at your medical review but it may also be simply be worth practising by obtaining a peak flow meter on which to perfect your technique.

Hopefully one of our qualified medical professionals such as @angrydoc or @nemesis1066 maybe able to shed more light.

Best of luck.


Thanks for all the help guys! It's been my dream since I was 14 and it would kill me for this minor error to shatter it all for me. I've worked so hard to get were I am at the minute and I shall keep training and running hard and practise my peak flow.
Don't know whether or not this would help, but for Asthma the navy would have you fill out a lung function diary. They would have you do that lung test to see the degree of variation in your results. May be worth having a chat with your doctor and using that as evidence, then reading Angrydocs sticky on a waiver based on the results - that's if a waiver can be done as you haven't been barred.


I've had talks and apparently it's my technique which is letting me down, I was told for my height and weight the requirement is 485 and I'm sort of floating around 450/470. I'm just worrying in my head that if I fail my second medical due to a low peak flow my dream is over
I know someone who was a Ship's Diver and a submariner (cough) and failed the initial S/M Vitalograph. As I , sorry he, was a volunteer, he was sent to INM (obviously not an option for the OP) where lots of tests were carried out, resulting in a get out of jail ticket. I always struggled with Vitalographs, but there is a very easy way to 'cheat', which I won't outline here. You just need to cheat consisitently.......... easy when you know how!


War Hero
Book Reviewer
It's all technique. Ask to see the nurse in your GP practice who deals with asthma, and ask her or him about technique and what you should be blowing (ooo err).
And the thread turns into 'Carry on Nurse' . Fully expect Jim Dale to come past on a trolley any second ;)
I had a recent grading medical and peak flow measurement was a part of it. The nurse remarked that my technique was different from those that normally have it done. As those who have posted before, it's all in the technique.
If I was you, I'd invest in a peak flow (available from a pharmacist or perhaps amazon) and it comes with a little chart. practice once or twice a day and you'll be able to chart your progress.
It's hard to describe the technique in sure you'll be able to find something online but its better to do a sharp blow from the back of you mouth than just to blow with you lips like you would with a whilstle

After re writing that about 15 times I've decided it's impossible to make it sound like I'm not giving head bobbing techniques


Doing everything I can with the technique and I'm managing to hit 500 which is vast improvement, just one last thing I'm just worried that 2nd time I may fail and will this mean I will not be able to join all together? And is there anything I can do to help my case when I go to my re medical if I am still not able to reach my required limit? Just need all the help and advice I can get.
My techniques was to shout "CHOW" with all the venom as if you'd shout **** when you'd hit your thumb with a hammer. get all the air out on the CH and keep HHHhhhhhhh ing til the W, get ready to catch yer ring piece on the final w


Your technique is fantastic!! I was struggling to get 450 but now with your technique I'm reaching 560 on the peak flow meter! I'm mind blown... Thank you so much
I also know about lung function tests at INM, they test all sorts of things lung efficiency, check for leaks etc, my out come was lung shape? Barrel chested, never did pass that S/M medical? But passed all SM training.
Good look, looks like the diver as given you a good blowing technique,
I'm in the same boat with @Pye96
I haven't taken my medical yet but, my peak flow score for a female of 23 and 159cm/53kg is 400 if I'm lucky.
I went to see the nurse about it and even using an inhaler to experiment with and see if it read higher didn't change a single iota.... would 400 pass @angrydoc ?
Everything else is working fine - this is insanely agonising me to think I'd fail over this


From what you're telling me you've done exactly the same as me with the whole situation, I checked with my doctors and everything and it was all ok, my medical was spot on apart from this one thing... Try doing different techniques like some people have suggested and it might help, it did in my case with the 'Chow' method and now I've just gotta wait till June for my re medical. Hope everything goes well for you as I'm also in the same boat.

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