Quote · The Diary Of A CEO with Steven Bartlett
Most Replayed Moment: Alzheimer's Starts 20 Years Before Symptoms! How To Protect Your Brain Now
Where this was said
Resistance Training as the #1 Brain Investment: The SMART Trial
At 1:22 · chapter starts 0:00
The episode opens with a pointed question: what is the single most compelling study proving exercise prevents Alzheimer's? Louisa Nicola doesn't hesitate — it's the SMART trial, which subjected people already showing mild cognitive impairment to 2–3 weekly resistance training sessions [1] — Louisa Nicola "Of all exercise modalities studied, resistance training delivers the biggest return on investment for brain health. The SMART trial proved …" 00:10 . The results were striking: participants didn't just slow their decline, they actively improved, showing faster processing speed, better fluid intelligence, and measurably less gray matter loss. From there, Nicola shifts to genetics, explaining the three-variant APOE gene system that influences Alzheimer's risk. Being a 3,3 carrier — the general population baseline — neither raises nor lowers risk. But carrying the APOE4 variant is a different story entirely: one copy raises risk 2–3 times; two copies raise it 10 times for men [2] — Louisa Nicola "The APOE4 gene is the strongest known genetic risk factor for Alzheimer's. One copy raises risk 2–3x; two copies raise it 10x for men — and…" 00:57 . The truly alarming number is for women: a single APOE4 copy approximately doubles the risk compared to a man with the same copy, bringing female risk to roughly sixfold. Two copies push that to 15-fold. Nicola mentions that Chris Hemsworth was publicly found to carry two copies of this gene — making him one of the most prominent faces of this genetic risk. The key message: genetic risk is real and quantifiable, but it is not a sentence.
Of all exercise types studied, resistance training provides the greatest return on investment for Alzheimer's prevention and brain health.
Of all exercise modalities studied, resistance training delivers the biggest return on investment for brain health. The SMART trial proved it: people with mild cognitive impairment who trained 2–3 times weekly preserved and enhanced their cognition while slowing gray matter loss.
The SMART trial showed that 2–3 resistance training sessions per week in people with mild cognitive impairment preserved cognitive function, enhanced processing speed, improved fluid intelligence, and slowed gray matter atrophy.
The APOE4 gene is the strongest known genetic risk factor for Alzheimer's. One copy raises risk 2–3x; two copies raise it 10x for men — and 15x for women. Chris Hemsworth has two copies.
Women carrying one copy of the APOE4 gene face approximately six times the Alzheimer's risk compared to the general population — double the risk of a male carrying the same single copy.
Women with two copies of the APOE4 gene have a 15-fold increased risk of Alzheimer's disease.
