Why it outranks everything in this aisle
Aerobic exercise is the intervention with the firmest evidence base in cognitive ageing. That is an uncomfortable sentence to publish on a site that sells a supplement, and it is still the accurate one.
The proposed mechanisms are plural and none of them is settled: better perfusion, effects on growth factors involved in maintaining neural tissue, improvements in sleep and mood that feed back into cognition, and the straightforward cardiovascular benefit that protects the vessels supplying the brain in the first place.
What counts
The useful threshold is not a step count. It is whether your heart rate rises and stays there for a while. A brisk thirty-minute walk, taken most days, at a pace where holding a conversation is possible but singing is not, is the version most of the research is actually describing.
- Frequency beats intensity. Five moderate sessions a week outperforms one heroic one, both in the data and in whether anybody keeps doing it.
- Resistance work earns its place too, mostly through what it does for balance, independence and the ability to keep doing the aerobic part at eighty.
- Outdoors has a side benefit. Morning daylight anchors the body clock, which feeds straight back into the sleep that memory consolidation depends on.
The honest caveats
Most of this evidence is observational, which means people who exercise differ from people who do not in ways beyond exercising. The randomised trials that exist are shorter and smaller than anybody would like, and their results are more modest than the observational picture suggests.
None of that changes the recommendation, because the downside risk of a daily walk is close to zero and the other benefits are not in dispute. But it is the same standard of evidence we apply to the ingredients in our own product, and it should be applied here too.
Starting from nothing
The failure mode is ambition. Somebody who has not exercised in a decade commits to an hour a day, lasts nine days, and concludes they are not a person who exercises.
Ten minutes, every day, attached to something that already happens — after breakfast, before the news — survives contact with a bad week. It can be lengthened later. An hour on Sunday cannot be shortened into existence.