Rhonda Patrick's Pre-Podcast Strategies for Focus Under Stress

Patrick Bet-David: What helps you stay calm and focused in a high-pressure setting such as public speaking?

Dr. Rhonda Patrick: Brief exercise is the best-supported tactic in this discussion. One study in 14 young adults found that 10 minutes of moderate-to-vigorous cycling improved reaction time on an antisaccade eye-movement task by up to about 50 milliseconds. The result was described as approximately 14 percent, but it was not a 14-percent improvement in overall cognition, memory, intelligence, or debate performance.

Broader meta-analyses find small average benefits from an acute exercise bout on selected executive-function tasks. High intensity is not clearly better than moderate intensity. Exercise can also produce a small reduction in state anxiety for some people, but responses vary and exhausting exercise can temporarily impair performance.

I also sometimes fast before an interview. Fat use occurs in both fed and fasted states. Fasting gradually increases fatty acids and ketone production, but there is no universal 12-hour switch. After an overnight fast, glucose remains an important brain fuel and the ketone increase varies with diet, activity, glycogen, age, and insulin sensitivity.

Beta-hydroxybutyrate is both a fuel and a signaling metabolite. Rodent and cell research links ketone metabolism with BDNF, neuroplasticity, and neurotransmitter pathways. Human evidence does not show that a 12-hour fast acutely raises brain BDNF, creates new neurons, increases GABA, or reliably improves situational anxiety. A large experimental meta-analysis found no meaningful cognitive difference between short-term fasted and fed states in healthy adults.

I have also used exogenous ketones before public speaking. Ketone esters and salts can rapidly raise blood BHB and temporarily suppress lipolysis. They do not reproduce all effects of fasting. Small human studies report mixed cognitive results, and no validated dose has been shown to prevent public-speaking anxiety in healthy people.

Exogenous ketones add energy and can reduce endogenous fat use during the dosing window. They do not automatically stop long-term fat loss, which depends on sustained energy balance. Products differ by ester, salt, dose, mineral load, and stereoisomer content. Nausea, reflux, cramps, diarrhea, taste, glucose lowering, and electrolyte load can matter.

Another practice is deliberate cold exposure. Cold water creates a strong sympathetic and catecholamine response that many people find alerting afterward. Controlled evidence does not show that two minutes at 49 degrees Fahrenheit reliably improves focus or lowers anxiety. Immersion can initially cause gasping, hyperventilation, panic, rapid heart rate, and a blood-pressure spike.

Cold immersion is not appropriate for everyone. Never plunge alone or combine breath-holding with water exposure. Cardiovascular disease, arrhythmia, uncontrolled hypertension, fainting or seizure history, cold urticaria, Raynaud disease, pregnancy, pulmonary disease, and medicines that affect temperature control require extra caution or clinical guidance.

PBD co-host: What about cold exposure or sauna before sleep?

Dr. Rhonda Patrick: A warm bath or shower one to two hours before bed has better evidence than a bedtime cold plunge. Passive heating can improve subjective sleep quality and shorten sleep-onset latency by increasing skin blood flow and supporting the later decline in core temperature. Evidence for deeper sleep is less certain.

Claims that sauna improves sleep through “somnogenic cytokines” are mechanistic speculation. Cold exposure close to bed can be alerting. Temperature, humidity, session length, hydration, health status, and individual response matter more than one fixed sauna temperature or a universal heat-cold sequence.