The Marathon Effect

2/16/26, Author: Jeremy Smith & Google Gemini

The Marathon EFFECT: GainS & Losses

As mentioned in my previous post, since my last biomarker check I built a healthy stack of daily supplements with the help of AI. I now have my new biomarker results back, and quite frankly I expected to see better results than I got. The problem is that I underwent more than one dramatic lifestyle change in the same period… so I completely messed up the experiment. Every good scientist knows, if you want to run a proper test, you must change only one variable at a time. Instead, I introduced a great amount of supplementation (and even did some incorrectly), but I also introduced the vast systemic stressor of intense physical training.

We are often told that exercise is the ultimate "fountain of youth." But as I discovered during my recent marathon training block, the relationship between peak performance and longevity is a high-stakes balancing act. When I received my latest biological age reports, I was hit with a paradox: My Pace of Aging had improved, but my Biological Age (OMICmAge) had actually gone up. Here is the breakdown of the "Marathon Effect," evidenced by my own biomarkers.

1. The Full Data: A Tale of Two Tests

To see the "Marathon Effect" in action, you have to look at the shift in my systems over a three-month intensive training window. While my total biological age rose, notice how many specific organ systems actually improved or held the line.

2. Understanding the "Marathon Effect"

In longevity science, extreme endurance training often follows a "U-shaped" curve. While moderate exercise is a powerful "geroprotector," high-volume training can cause significant acute physiological stress that "wreaks havoc" on internal metrics:

• Kidney & Heart Stress: Studies show high-volume running increases muscle breakdown products (like creatinine) and inflammatory cytokines that biological clocks interpret as organ aging.

• The Over-Training Threshold: Once you exceed 5 hours (300 minutes) of vigorous exercise per week—common in marathon plans—the "anti-aging" benefits for the heart and kidneys often plateau or temporarily regress.

• The Snapshot Fallacy: This isn't necessarily permanent damage; it's an acute state of systemic inflammation. If you test within 48 hours of a long run or during a peak week, your "odometer" reflects that stress.

3. The "Hidden" Influencers: Creatine and High Protein

My OMICmAge rose to 44.9, largely driven by metabolic and kidney "aging" signals. However, these are often "noise" created by a high-performance lifestyle:

• Creatine & BUN: I support my training with a high-protein diet and 2.5g of Creatine Monohydrate daily. My blood labs showed a BUN of 24 mg/dL (high-normal) and Creatinine at 1.19 mg/dL. To an algorithm, this looks like aging; to an athlete, it's just the signature of protein turnover.

• Glucose Memory: My epigenetic Fasting Glucose was in the 90.5th percentile, yet my actual blood glucose was a stellar 79 mg/dL. My DNA was still holding the "memory" of high-carb fueling required for 20-mile runs.

4. Offsetting the Damage: Why I'm Still Winning

The most exciting takeaway is that my Metabolic, Inflammation, Kidney, Liver, and Musculoskeletal ages all went down despite the training volume. This implies my protocol—including L-Proline, L-Lysine, Grape Seed Extract, and my 2ata hyperbaric chamber—is successfully "offsetting" the traditional marathon tax. My telomeres even grew to 7.28, giving me a Telomere Age of 37.7.

5. Moving Toward the "Goldilocks Zone"

I am now adjusting my strategy to stay in the longevity "sweet spot":

• The 80/20 Rule: Doing 80% of runs in Zone 2 to build mitochondrial density without the massive inflammatory spikes of high-intensity training.

• Fixing the "Beet Root" Sabotage: I was accidentally crashing my Zinc (60 mcg/dL) because the oxalates in my pre-run beets were blocking absorption. Low zinc is a major AFib trigger; I now time these 4+ hours apart.

• Strategic Testing: I’ll now only take biological age tests during a taper week or after a week of active recovery to see my "true" age.

The verdict: My organs are younger, my telomeres are growing, and I’m aging slower than 80% of the population. I just had to learn how to stop training like an athlete and start living like a longevity expert.