Basal Lipolytic Rate

Mr_Knight

Like a few others here, sometimes I like to wander around the research paper universe looking for something to catch my eye. This evening, it was a paper on basal lipolytic rates, and what happens to them under fasting conditions. Bottom line: fasting/re-feed cycles change stored fat in ways that make it much quicker to metabolize.

How much quicker? After a 72h fast/refeed cycle, fat was metabolizing at 3x the normal rate. That's a *huge* difference!

I was curious how short the fasting/refeed cycle could go before the improvements went away. There were a couple of papers showing BLR improvements of 20-25% with fasting cycles as short as 18h.

Now that I found interesting. The higher your BLR, the larger the deficit you can sustain before your body starts consuming the more interesting bits of itself. An 18h fast is a just a typical intermittent fasting (IF) pattern - and since IF is just a mildly dramatic method of meal timing, it implies that some forms of meal timing will, in fact, have a meaningful impact on weight loss.

This might tie back to a throwaway comment Lyle McDonald made on a forum somewhere, where he did the Fermat's Last Theorem thing and said without any real explanation that the 31 cal/pound fat metabolization limit wasn't really a limit if you did things right.

There are a few papers I've yet to meander through, at least two of which also claim that macronutrient ratios have an effect on BLR. Looking forward to reading those, as they should be pretty mind-blowing.

Fun stuff!

Nikkei74

Interesting! What variety of fasting in the 72 hour cycle?

sijomial

Interesting - do you have a link to the paper?

Purely anecdotal - I do the 5:2 form of IF and noticed two very distinct changes over a period of months.

1/ My ability to train fasted improved from not at all (wobbly and weak) to fasted training feeling totally "normal" in terms of energy and performance.
2/ My ability to cycle longer distances unfed improved dramatically.

Mr_Knight

I'm going to gather a bunch of these links into a more coherent "scientific post", hopefully that will answer questions. A couple of other results that popped out...

- macronutrient intake affect lipolysis - swinging significantly to/from carbs under iso-caloric conditions changes the rate at which stored fat can be metabolized.

- the pattern of fat storage - the way your body distributes fat as it stores it - affects how quickly the fat can be metabolized. People who store fat more evenly across their entire bodies are at a weight loss advantage over people who store fat more "clumpily" (conversely, people who "clump" are at a famine advantage over those who don't).

Springfield1970

Wow! Thanks for the sharing!