A published double-blind trial on 48 runners found that NMN at a specific dose measurably improved aerobic efficiency, oxygen utilization, and ventilatory thresholds during exercise. Here is what that means if you are a woman over 40 who trains.

There is a particular kind of frustration that active women in their late 40s and 50s know well.

You are not the person who skipped the gym. You have been consistent. You log your Zone 2 sessions. You track your runs. You lift. You recover with intention. And yet at some point in the last few years, your aerobic output started quietly declining in ways that discipline alone could not explain.

Your breathing gets labored at intensities that used to feel easy. You hit what runners call "leg death" earlier in long runs. Your 10K pace has slipped, not because your legs gave out, but because your lungs did. Recovery takes longer than it should for someone who does everything right.

Most women blame hormones and move on. Some buy a different running shoe. A few add more miles and get worse. Almost none of them trace the problem to the place where it actually begins: inside the mitochondria of their skeletal muscle cells.

This is a cellular efficiency story. And it starts with a molecule called NAD+.

NAD+, or nicotinamide adenine dinucleotide, is the coenzyme your mitochondria require to convert oxygen into ATP, the usable energy currency of every muscle contraction. Without adequate NAD+, your cells cannot extract energy from oxygen efficiently. The oxygen is there. Your lungs are pulling it in. Your cardiovascular system is delivering it. But your muscle cells cannot finish the job.

By your mid-40s, your NAD+ levels have declined by roughly 50 percent from their peak. That decline does not announce itself. It arrives gradually, disguised as "just aging" or "needing more recovery." It shows up as a flattening VO2 max, a lower ventilatory threshold, and a body that seems to need more effort to produce the same output it managed three years ago.

This is not a training problem. It is a substrate problem.

Researchers from Guangzhou Sport University and four affiliated institutions decided to test whether restoring NAD+ precursor availability could reverse any of this decline in active people. Their study, published in the Journal of the International Society of Sports Nutrition, ran a 6-week randomized, double-blind, placebo-controlled trial on 48 healthy amateur runners. Not sedentary adults. Active people. The kind of person reading this.

The participants followed a strict training protocol, 5 to 6 running sessions per week, 40 to 60 minutes per session. Every cohort trained identically. The only variable was a daily NMN capsule at one of four doses: 300 mg, 600 mg, 1,200 mg, or a placebo. All participants were measured at baseline and again at 6 weeks on several key aerobic biomarkers.

The results were unambiguous in the clinically relevant dose groups.

Subjects in the 600 mg and 1,200 mg NMN cohorts demonstrated measurable improvements in oxygen utilization during active exercise. Their skeletal muscle was extracting and using oxygen more efficiently at equivalent training intensities. Their VO2 max percentages improved. More practically, their ventilatory thresholds shifted. They could sustain higher training intensities before reaching heavy breathing and lactic onset. The moment where your chest tightens and your pace has to fall moved further up the effort curve.

The 300 mg group and the placebo group did not show these same gains. Same training. No NMN advantage.

One finding matters for calibrating honest expectations. The trial did not find significant increases in absolute peak power. NMN did not turn these amateur runners into different athletes. What it did was allow their existing aerobic capacity to operate closer to its potential.

As Omre's founding physician, Dr. Pedram Kordrostami M.D., explained it:

"While the study hasn't found an increase in peak fitness, NMN appears to enhance aerobic efficiency during exercise, a valuable edge for anyone committed to training and healthy aging."

That sentence deserves a second read. Efficiency is the precise word. At moderate training intensities, the NMN cohorts were getting more work done per unit of oxygen consumed. That is not a marginal gain when you are running for an hour, 5 days a week, in your late 40s or 50s. That is the difference between a run that ends with reserve and a run that ends with nothing left.

The mechanism behind this matters. NMN is a direct precursor to NAD+. When you supplement with NMN, you are giving your cells the raw material to replenish NAD+ levels that have been quietly declining since your mid-30s. Higher NAD+ means more functional mitochondria. More functional mitochondria means more efficient oxygen-to-ATP conversion in skeletal muscle. That conversion is what your VO2 max actually measures.

You are not fixing your lungs. You are fixing what happens downstream of your lungs.

Biohackers in Omre's customer base who train have reported this shift in terms that track exactly with the trial data. A 50-year-old registered nurse who had been running for years described going from a 13-minute per mile 10K pace to 10 minutes per mile "without being short of breath" after two months of NMN supplementation, with faster recovery as well. A woman training for a fall marathon noted that her long slow runs had "become pleasant" and that the "leg death toward the end of 14 and 15 mile runs" had stopped. An avid tennis player in her early 50s reported "greater energy levels and endurance" followed by improvements in metabolic health over sustained use.

These are not testimonials from people who started exercising. These are people who were already in the gym, on the trail, on the court. The NMN removed a ceiling they did not know was a metabolic ceiling rather than a training ceiling.

Some customers reported things the trial was not designed to measure. Better sleep quality. Noticeably clearer skin. Several had colleagues and friends comment unprompted on their appearance. A woman who called herself highly skeptical of supplements noted that brain fog was "the first to go" within two weeks of starting, followed by the energy and physical performance improvements. These secondary effects are consistent with what broader NAD+ research would predict, as the coenzyme is involved in DNA repair, sirtuin activation, and cellular stress response beyond pure mitochondrial function.

Now to the question skeptical researchers always ask: is the product itself trustworthy?

The supplement industry has a documented quality problem. Third-party lab testing of NMN products has found significant variance between labeled and actual NMN content across brands, with some products containing a fraction of what the label claims. This is not a minor concern when the clinical data shows that 300 mg produced no measurable benefit and the threshold effect begins at 600 mg. Getting the dose wrong means getting no result.

Omre's NMN is independently verified at over 90 percent purity, produced in a GMP-certified facility, and third-party tested. That purity standard is what appears on the label and what has been independently confirmed. It is also why customers who have tried other brands report staying with Omre. The purity matters because the dose matters.

The clinically validated dose from this trial is 600 mg per day.

That is what Omre's standard serving delivers.

If your training effort has been consistent but your aerobic output has been quietly declining, and you have ruled out everything behavioral, this is worth looking at seriously. Not as a shortcut. As a substrate correction. The study is published, peer-reviewed, and indexed on PubMed. The mechanism is established in the scientific literature. The dose is known. The product purity is independently confirmed.

Try Omre NMN + Resveratrol at the clinically tested 600 mg dose. Track your ventilatory threshold over 6 weeks. See if the ceiling lifts.

The full clinical trial is available for anyone who wants to read the methodology and the raw outcome data before deciding: pmc.ncbi.nlm.nih.gov/articles/PMC8265078