I’m 36 and have just decided to step up my training from running 5k three times per week, to training for a half marathon. I have close to a sub 20 5k time and V02 max of 51 so I am in fairly good shape.
During each of my runs, I always run with a fairly high intensity given the infrequency and shorter distance. Two years ago when I started this regime, I would get shortness of breath periodically for a day or two after these runs, but as my fitness improved, although I would still get shortness of breath, it would not happen to the same degree, so I learned to live with it and assumed it was normal to go through that after training. Doing an x-ray, bloodwork and EKG with my doctor showed no issues.
I’ve now just started a new program (The F.I.R.S.T 3plus2) which focuses on intensity over volume, and after my first 10km, I have had the same shortness of breath occurring for days after, but now with a chest tightness and slight pain. I again did blood work and an EKG, but everything came back normal.
Is this shortness of breath for days after running with a high intensity normal or should I seek out other opinions?