In summary, I believe I am getting useful improvements in my cholesterol balance as a result of a few months of HIIT. (But I can’t be absolutely certain it is the HIIT that is doing it).

I started HIIT at the start of last November, just after buying an exercise bike. See my first post here. Some scientific studies of HIIT say things like “participants showed improvements in XYZ after 16 weeks”. So I had an NHS health-check after 4 months, hence the start of March.

My cholesterol values are now (age nearly 69) significantly better than they were when last checked (age 62). And they weren’t too bad then. Perhaps part of the improvement is the result of other life-style changes. I’ve improved my food and cooking over the last year. But some scientific studies showed cholesterol improvements from HIIT, so I was hoping to see them. And I did.

The science typically shows that HIIT doesn’t reduce total cholesterol, but changes the balance from “bad cholesterol” (LDL) towards “good cholesterol” (HDL). Studies have shown that it is this balance that makes the biggest reduction in the risk of cardiovascular disease, rather than simply total cholesterol. And it is this balance that has improved for me.

Here are the numbers, for 2009 and 2016, in mmol/L. Sorry if numbers make your eyes glaze over!

(Total) Cholesterol: 2009, 5.3; 2016, 5.3.
HDL (“good”) cholesterol: 2009, 1.4; 2016, 2.4.
LDL (“bad”) cholesterol: 2009, 3.4; 2016, 2.6.
Non-HDL cholesterol, including VLDL (“bad”) cholesterol: 2009, 3.9; 2016: 2.9.

There is a body of evidence that the ratio “Cholesterol/HDL” is very important. Typically, the smaller the number, (in other words, the higher the proportion of HDL), the better. Less than 6 is OK.

My ratio has gone from 3.79 in 2009 (not bad) to 2.21 in 2016 (very good). The science indicates that this should help reduce cholesterol in the wrong places, and move unwanted cholesterol from where it shouldn’t be towards the liver where it will be disposed. This ratio change appears to have made a significant improvement to my risk of a cardiovascular event in the next 10 years.

I am deliberately not taking any medication, either prescribed or over-the-counter. I am anxious to avoid ever needing statins, and I think HIIT will help. (Assuming that it has played a significant role in this improvement).

(My other values are OK, but have not improved to this extent).

(I’ve done HIIT in the past, but not with the same rigour that I’m doing now).