Originally Posted by
Redbullet
No, it was just curiosity and, due to practical reasons, I'll never be able to measure my blood pressure while riding.
But with regards to healthcare provider, I think no one would advise HIIT, even for people below 30 years of age. There is some kind of disclaimer here: they will avoid being accused for bad advice, even if the risk would be 1/10000 persons and many of the remaining 9999 would have some benefits from HIIT.
The risk of anything bad occurring at the result of HIIT in a healthy person without known cardiovascular disease is negligible—far, far, below 1/10,000 individuals—and there is no basis for believing the risk is any higher than that of longer duration intervals performed at high intensity.