I just got back from a visit with my cardiologist. He (and his exercise physiologist) were the one's who told me last year that even though I was logging 150 miles week, I was dogging it -- and I needed to get my heart rate up. WAY up!
This time they added HIIT to my regimen -- because, they say, it has proven cardiovascular benefits. I of course didn't ask them for the studies to prove it (most physicians would consider that bad form!) but they seem to know what they're talking about.
The exercise physiologist acknowledged that there are a number different HIIT routines and there is not a lot of evidence to prove which routine is best. But he said that they at the Cleveland Clinic have settled on:
4 minutes MICE @ 75-80% max heart rate
4 minutes HIIT @ >90% max heart rate
... repeat 3-4 intervals of each...
And here, I thought HIIT was strictly for performance and fitness. I had no idea it had cardiac benefits as well...
And, as a side note: as result of the diet and exercise regimen I've been following I am now, for the first time in almost 20 years, officially off all of my heart medications...
20 years ago my total cholesterol was nearly 300 and my LDL was 195. Today, after 6 months without a statin it was 175 & 106 respectively (not great numbers, but good enough).
And, 20 years ago my blood pressure was 160/95 and today, after a couple weeks without any blood pressure medication it was 118/68.
So, all this stuff we talk about on this forum DOES in fact work! We may quibble over the details but most all of us are doing our best to eat well and train well. For me -- this stuff is doing things that I never thought were possible.