Most people optimizing their performance are staring at the wrong variables. They're tracking protein intake, timing their creatine, debating which pre-workout formula is worth the money. Meanwhile, the lever with the most evidence behind it — the one that expands the very substrate that exercise works with — sits on every kitchen table.
That's DiNicolantonio's core argument, and it's harder to dismiss than you'd expect. Salt preloading increases plasma volume before you even touch a barbell. Your heart pumps more efficiently. Metabolic waste clears faster. The burning sensation that forces you to stop — that's hydrogen ion accumulation — takes longer to build. You don't get stronger by surviving more reps. You get stronger by accumulating more quality work, session after session, over years. Blood volume is the quiet variable that governs how much quality work your body can actually absorb.
The sauna piece connects cleanly to everything Rhonda Patrick has documented — and to a 2022 study in our knowledge base showing that just 12 minutes of passive heat exposure at extreme temperature produced measurable acute strength improvements in a relative maximum repetition test. What DiNicolantonio adds is the mechanism for the longer arc: two weeks of daily sessions lowering baseline core temperature. A cooler starting point means more thermal buffer before heat-sensitive enzymes start shutting down ATP production. You're not just tolerating heat better — you're changing the physiological ceiling of what's possible in any given training session.
Where there's less consensus is the periodization of preloading itself. DiNicolantonio makes a nuanced point that not every session should be maximally preloaded — deliberate mild dehydration during some training blocks drives its own osmotic adaptation. That runs counter to the instinct most people have, which is to always hydrate aggressively. The body needs the signal of mild stress to adapt. Protect it from every challenge, and you slow the adaptation.
For typical sessions: 1,000mg sodium with 10–16oz of water, 30–60 minutes before training. For competition or genuinely hard efforts: 3,000–4,300mg with 26–34oz. Slightly saltier than blood — counterintuitively, hypertonic solutions are retained more completely than isotonic ones.
For heat adaptation: daily sauna for two weeks produces measurable changes. Even 15–20 minutes at moderate temperature begins the process. If you already train hard, adding sauna extends the adaptive stimulus without adding training load — which is a rare thing in performance optimization.
What strikes me reading DiNicolantonio alongside the broader research is how consistently the most powerful interventions are also the most unglamorous. Blood volume. Consistent resistance training. Sitting in a hot room. None of these will sell a supplement. All of them will build a body that functions well at 70.
The salt protocol is cheap, legal, and grounded in decades of sports science. The resistance training recommendation is not new. The sauna data has been replicated across populations for thirty years. What's missing isn't information — it's the willingness to commit to the boring fundamentals while the supplement industry offers more exciting alternatives.