Key insights
- Sequence is goal-dependent. There is no universal right answer — the research supports different orders for different outcomes.
- Sauna first, end on cold is the default. It produces the sharpest norepinephrine spike and strongest sympathetic activation. Huberman recommends it for focus, mood, and performance.
- End on cold for metabolic benefit. The Søberg Principle: ending on cold forces the body to rewarm internally via brown adipose tissue, which is the metabolic work. Ending on heat short-circuits it.
- The two-hour timing window matters for sleep. Sauna within 30 minutes of bed can delay sleep onset. Finished 1–2 hours out, it accelerates it.
- Cardiovascular benefits are sequence-independent. Either order produces the vascular adaptations documented in the Laukkanen cohort studies.
- Cycling beats single blocks. Patrick recommends 3–4 rounds of 15–20 min sauna / 2–3 min cold rather than one long heat block followed by one plunge.
Most people treat this question as a preference. Warm first because it feels like a natural progression. Cold first because it seems more disciplined. Neither answer is wrong — but neither is complete.
The sequence matters because sauna and cold exposure trigger different, sometimes competing, physiological cascades. What you do first shapes what the second intervention can accomplish. Getting the order right means understanding what each stimulus actually does to your body — and what you are trying to get out of the session.
Below is the research on contrast therapy, the arguments for each approach, and the protocol recommendations from the researchers who have studied this most carefully.
What Contrast Therapy Actually Is
Contrast therapy — deliberately alternating between heat and cold exposure — is not a new wellness trend. Nordic cultures have practiced sauna-to-cold-plunge cycling for centuries. What is new is the mechanistic research explaining why it works.
The physiological logic is this: heat causes peripheral vasodilation — blood vessels near the skin surface expand, heart rate elevates, and the body works to dissipate thermal load. Cold causes the opposite: vasoconstriction, heart rate drop, and a sharp spike in norepinephrine. Alternating between these two states creates a powerful cardiovascular stimulus — a kind of passive interval training that some researchers describe as producing a "vascular pump" effect on the circulatory system.
But vasodilation and vasoconstriction are not the only variables. Heat and cold also affect cortisol, growth hormone, brown adipose tissue activation, norepinephrine, and the inflammatory response to exercise — each of which is sensitive to sequence.
The Case for Sauna First
This is the sequence most researchers recommend as the default, and Dr. Andrew Huberman has articulated the clearest mechanistic rationale for it.
Heat exposure raises core temperature and prepares the nervous system for the cold stimulus that follows. When you move from sauna into cold water, the thermal contrast is at its maximum — producing the sharpest norepinephrine spike, the strongest vasoconstriction response, and, critically, the most potent activation of the sympathetic nervous system. Ending on cold locks in that sympathetic activation: heightened alertness, improved focus, elevated mood. This is why sauna-then-cold is the protocol Huberman recommends for morning or pre-performance sessions.
There is also a practical argument: heat loosens the body. Fifteen to twenty minutes in a sauna at 80–100 °C raises muscle temperature, increases elasticity, and reduces the psychological barrier to cold immersion. For most people, particularly those new to cold exposure, starting warm makes the cold plunge more achievable and therefore more consistently practiced.
"The sauna-to-cold-plunge sequence — ending on cold — is what I recommend for protocols aimed at mood, focus, and resilience building." — Andrew Huberman
Watch Huberman on contrast protocols: Huberman Lab Ep. 69 → 64:32
The Case for Cold First
There is one significant exception to the sauna-first default — and it is supported by peer-reviewed research.
Dr. Susanna Søberg, whose 2021 study on deliberate cold exposure is among the most-cited in the field, recommends ending on cold when the goal is brown adipose tissue (BAT) activation and metabolic benefit. Her reasoning: cold is the primary stimulus for BAT activation. Brown adipose tissue burns energy to generate heat — a process called non-shivering thermogenesis — and it is strongly implicated in metabolic health, insulin sensitivity, and long-term body composition.
If you end a contrast session with heat, the body's thermogenic response to cold is partially neutralised — you warm up externally rather than generating internal heat through BAT activation. Ending on cold forces the body to rewarm itself, which is precisely the metabolic work Søberg's research is measuring.
This has become known informally as the "Søberg Principle": end on cold if metabolic benefit is the primary goal.
Watch Dr. Søberg explain the principle: Huberman Lab with Søberg → the Søberg Principle
What the Research Says: Key Studies
Søberg et al. (2021) — the landmark study on thermogenesis and cold exposure — found that 11 minutes of cold immersion per week (distributed across multiple sessions) was sufficient to produce measurable increases in brown adipose tissue activity and norepinephrine levels. The study did not directly compare contrast therapy sequences, but Søberg's protocol recommendations derived from it emphasise ending on cold.
Laukkanen et al. (2022) reviewed the cardiovascular effects of contrast bathing and found that alternating heat and cold exposure produces vasodilatory and vasoconstrictive adaptations that improve vascular compliance and reduce arterial stiffness over time — effects not observed with sauna or cold exposure alone. The review did not identify a sequence-dependent difference for cardiovascular outcomes specifically.
Higgins et al. (2017) examined post-exercise recovery using contrast water therapy and found that cold-first sequences reduced perceived muscle soreness more effectively in the 24 hours following exercise, while heat-first sequences were associated with greater subjective recovery and readiness. The practical implication: if the contrast session is part of post-workout recovery, the goal determines the order.
The Goal-Dependent Framework
This is the honest answer to the question: the right sequence depends on what you are trying to accomplish.
| Goal | Recommended Sequence | Rationale |
|---|---|---|
| Focus, alertness, mood | Sauna → Cold | End on sympathetic activation; norepinephrine spike from maximum thermal contrast |
| Metabolic benefit, BAT activation | Cold → Sauna, ending on Cold | Søberg Principle: force the body to rewarm internally |
| Post-workout recovery | Sauna → Cold | Greater subjective recovery and readiness; heat reduces muscle tension before cold immersion |
| Sleep quality | Sauna → brief Cold → end warm, then sleep | Post-sauna cooling aligns with circadian temperature drop; avoid ending too cold if sleep is immediate goal |
| General cardiovascular adaptation | Either | Cardiovascular benefits appear sequence-independent per Laukkanen review |
Dr. Rhonda Patrick's Position
Patrick's contrast protocol recommendations align with Huberman's on the default sequence — sauna first — but she adds an important nuance around timing. She recommends avoiding sauna immediately before sleep if ending on heat, since elevated core temperature can delay sleep onset. If the session is evening-timed, she suggests either ending on a brief cold exposure (to accelerate the return to baseline core temperature) or timing the entire session to finish at least two hours before bed.
On the question of session structure, Patrick typically recommends three to four rounds of sauna-to-cold cycling rather than a single long heat block followed by a single cold plunge. Each cycle: 15–20 minutes in the sauna at 80–100 °C, followed by 2–3 minutes of cold immersion at 10–15 °C (50–59 °F), repeated.
Read our full breakdown of Dr. Rhonda Patrick's sauna protocol.
Practical Protocol: What to Actually Do
For most people, most of the time, this is the structure that synthesises the research:
Default protocol (focus, mood, performance)
- Round 1: 15 minutes sauna at 80–100 °C
- Cold plunge: 2–3 minutes at 10–15 °C
- Round 2: 15 minutes sauna
- Cold plunge: 2–3 minutes — end here
- Hydration: minimum 500 ml water per 15 minutes of sauna time
- Timing: morning or early afternoon
Metabolic protocol (BAT activation, body composition)
- Cold plunge first: 2–3 minutes at 10–15 °C
- Sauna: 15–20 minutes
- Return to cold: 2–3 minutes — end here and allow the body to rewarm naturally
- Do not use towels or external heat immediately after the final cold exposure
Recovery protocol (post-workout)
- Wait 30–60 minutes after training before beginning
- Sauna first: 15 minutes
- Cold plunge: 3–5 minutes
- Optional second sauna round: 10–15 minutes
- End on cold or warm depending on whether sleep follows within 3 hours
A Note on Temperature and Equipment
The benefits described in the research above are temperature-dependent. Most clinical studies on sauna use traditional Finnish-style dry saunas operating at 80–100 °C (176–212 °F). Most cold exposure studies use water at 10–15 °C (50–59 °F) — cold enough to trigger the norepinephrine response but not cold enough to pose hypothermia risk for healthy adults.
Infrared saunas, which typically operate at 50–65 °C (122–149 °F), may not reach the threshold temperatures required to replicate the cardiovascular and hormonal effects documented in these studies. If contrast therapy is a primary use case for your installation, the equipment specification matters.
Schedule a consultation to discuss which sauna and cold plunge combination is right for your goals and space.
References
Laukkanen JA, et al. (2018). Cardiovascular and other health benefits of sauna bathing: a review of the evidence. Mayo Clinic Proceedings. PubMed
Huberman A. (2022). The science and health benefits of deliberate heat exposure. Huberman Lab Podcast, Episode 69. YouTube
Søberg S, et al. (2021). Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men. Cell Reports Medicine. PubMed
Laukkanen JA, et al. (2022). Sauna bathing and cardiovascular health: an overview of the evidence. Progress in Cardiovascular Diseases. PubMed
Higgins TR, et al. (2017). Contrast water therapy and exercise induced muscle damage: a systematic review and meta-analysis. Exercise Immunology Review. PubMed
Patrick RP. (2021). Hyperthermic conditioning: the robust effects of sauna use on health, performance, and longevity. FoundMyFitness. FoundMyFitness