Week 11: What David Sinclair Is Teaching Me About What I'm Already Doing
Best Health in a Lifetime: Week 11 Check-In
I have been reading David Sinclair’s Lifespan this week.
Sinclair is a Harvard geneticist who has spent decades studying why we age and what the science actually says about slowing the process. The book is dense with research but the core argument is simple: aging is not inevitable the way we think it is. It is a disease, or at least it behaves like one, and the mechanisms that drive it are increasingly understood.
I am eleven weeks into a project about health optimization and I picked up this book expecting to learn new things. What I did not expect was to recognize so much of what I am already doing in the science he describes.
The NAD+ Connection
One of Sinclair’s central arguments is that NAD+, a molecule essential for cellular energy production and DNA repair, declines significantly with age. By the time you are in your 50s your NAD+ levels can be half of what they were in your 20s. That decline is directly linked to the aging process at a cellular level.
I have been taking NMNH, the reduced form of NMN and one of the most direct NAD+ precursors, every morning since mid-May. I added it because the research pointed in a clear direction. Reading Sinclair this week, the rationale became significantly clearer. He is describing the exact mechanism that NMNH is designed to address.
AKG is also in my morning stack. Sinclair discusses alpha-ketoglutarate as one of the compounds with meaningful evidence for longevity signaling. Again, not something I added because of this book. Something I added months ago that the book is now explaining back to me.
What the Data Looks Like From a Longevity Lens
Sinclair talks extensively about the biomarkers that matter for biological age. Resting heart rate. Heart rate variability. VO2 max. Fasting glucose. These are not fitness metrics in his framing. They are indicators of how fast your cells are aging.
I have been tracking three of those four every single day for eleven weeks.
RHR started at 76 bpm on April 1st. It is now consistently in the high 50s to low 60s, with readings as low as 46 bpm on my best days. Sinclair would describe that 30 point drop not just as improved fitness but as a measurable reduction in biological age.
HRV started at 30ms. It now regularly sits in the 50s and 60s at home with peak readings above 90ms. In the longevity literature HRV is one of the most sensitive indicators of nervous system health and cellular resilience. Mine has more than doubled.
VO2 max has moved from below average for my age group to 35.76 this week, which sits in the good category for a 55 year old male. Sinclair is direct about VO2 max. It is one of the single strongest predictors of longevity in the literature. More than almost any other metric you can track.
I did not start this project to reduce my biological age. I started it to feel better and perform better. But eleven weeks of data is starting to suggest those goals are the same thing.
Week 11 in Numbers
This was a quieter week by design. After a stretch of intense travel, big physical efforts, and a lot of demands on the nervous system, I let the body settle into a more sustainable rhythm.
Steps averaged just under 10,000 per day. Active calories consistent at 580 to 670 most days. Protein averaging 127g, just under the 130g target on a couple of days but within range across the week. Weight holding at 191 to 192 lbs.
The exercise routine this week looked like what it increasingly looks like at home: evening walks, some with the 28 pound weighted vest, and bike rides when time and weather cooperate. No single dramatic effort. Just the accumulated output of consistent daily habits that have now been running for eleven weeks.
RHR trending down through the week, ending at 59 bpm on Tuesday. HRV bouncing around, 28ms early in the week then recovering to 85ms by the weekend and settling in the 50s and 60s through the week. The nervous system responding well to a calmer week.
VO2 max nudging upward to 35.76, the accumulated aerobic work of the past several weeks showing up in the cardiovascular adaptations.
What Comes Next
Europe next week. A work trip that will add the international travel variable to the data set for the first time. New time zones, different food environment, longer flights. The travel disruption pattern I’ve documented across six SF trips is about to face a more significant test.
I’m going in with eleven weeks of habits that have proven resilient across demanding work weeks, family commitments, and the full chaos that travel throws at you. I’m curious what the data looks like after a transatlantic flight.
Sinclair would probably tell me to keep the exercise going even on travel days, watch the sleep carefully, and not let the time zone shift disrupt the supplement routine. That’s also exactly what this project has been teaching me independently.
The reading list and the data are pointing in the same direction. That feels like a signal worth paying attention to.
What are you reading that’s changed how you think about your health? I’d be curious what’s on other people’s lists. Drop it in the comments.