Non-cardiac related causes of fatigue & shortness of breath associated with vigorous exercise

[Mickey07450]

Non-cardiac related causes of shortness of breath and extreme fatigue during and after vigorous exercise such as hiking and biking up steep hills.

[Mickey07450]

Thank you!  That's the best explanation I have received for my fatigue and shortness of breath during and after vigorous exercise.  In fact my PCP has referred me to a pulmonary physician, so that may finally give me some answers, and I hope some treatment options.

[ed34]

If the heart is in perfect condition then the next thing to investigate are the lungs. Perhaps a lung function test should be given to test capacity and absorption/exchange of gases. If the lungs are not adequately absorbing oxygen into the bloodstream, your muscles will suffer fatigue. I remember reading somewhere that with each breath you take, the heart uses 80% of the available oxygen from each breath which only leaves 20% for the rest of the body. If the lungs are impaired then this will be less.