Sauna + Cold Plunge on HGH: I Tested My IGF-1 Before and After a 30-Day Protocol

My IGF-1 went from 224 to 248 ng/mL over 30 days of structured sauna and cold plunge protocol. My Oura HRV average improved from 58ms to 67ms. My deep sleep minutes, which I’ve been tracking obsessively since my first article, ticked from 102 to 108.

Is that a lot? No, not compared to my first six months of tracking. But in 30 days, targeting a protocol I hadn’t tried before, those are real moves in the right direction — and the mechanism behind why they happened is interesting enough to write about.

TL;DR: Contrast therapy (sauna followed immediately by cold plunge, 3x/week for 30 days) produced measurable IGF-1 improvement and HRV gains for me after my other optimization variables were already established. It’s not a primary intervention — it’s a secondary one. Don’t start here.

Why I Started Tracking This

After my first six months tracking deep sleep and IGF-1 — which I wrote up in detail in that first article on the correlation between deep sleep minutes and IGF-1 — my numbers had stabilized at a good plateau. IGF-1 was sitting at 224 ng/mL, deep sleep averaging 102 minutes per night on Oura, total T in the 680 range. Protocol locked in, bloodwork healthy, feeling genuinely better than I did at 35.

The engineer in me got bored. When the system is running well, I start looking for edge cases to test. And I’d been reading about the (Susanna Søberg protocol, a research-backed cold exposure approach recommending 11 cumulative minutes of cold immersion per week across multiple sessions) Susanna Søberg protocol, sauna-induced heat shock protein responses, and the emerging data on contrast therapy and HRV. Ron Males had mentioned sauna in the Anabolic Alchemy program as a secondary GH lever — something worth adding after the primary stack (sleep, training, insulin) was already solid. I had the primary stack solid. Time to test the secondary.

I want to be clear about the frame before I show the data: 30 days is a short experiment. I’m one person. I can’t isolate sauna and cold plunge from everything else in my protocol because I didn’t stop everything else — that would have introduced a different set of confounders. What I can say is that during a period when nothing else changed materially, these numbers moved.

The Protocol

I have access to a Finnish-style sauna at a gym near my house in Austin. Not infrared — dry heat, around 178-185°F. The cold plunge there sits at approximately 52-55°F depending on the day.

The protocol for 30 days:

• 3 sessions per week of contrast therapy: 20 minutes sauna, immediately into cold plunge for 2-3 minutes, 5-minute rest, optional second round
• 2 additional cold plunge sessions per week on non-sauna days: 3-4 minutes at the same temperature, no sauna
• Total cold exposure: approximately 11-13 minutes per week (hitting the Søberg minimum)
• Sessions timed: late morning on training days (after lifting, not before)

One thing I specifically did not do: post-workout cold within 2 hours of training. Ron flagged this to me explicitly when I told him the plan — cold immediately after strength training may blunt the hypertrophy and acute hormonal response from the session. So I kept training and cold at least 3-4 hours apart, or on separate days.

Baseline — Day 0

Marker	Day 0 Value	Units	Notes
IGF-1	224	ng/mL	Morning fasted blood draw
HRV (30-day Oura avg)	58	ms	Prior 30-day average
Deep sleep (30-day avg)	102	min/night	Prior 30-day average
Total T	682	ng/dL	Same blood draw
Free T	19.4	pg/mL	LC-MS/MS method
Fasting insulin	5.8	µIU/mL	Same blood draw

For context: these are my numbers after 6+ months of prior optimization. The IGF-1 of 224 was already 90% above where I started at 118. I wasn’t starting from a deficit — I was testing whether I could squeeze more signal out of a protocol that was already working.

Week 1–2: The Adjustment Period

The first week was uncomfortable in ways I expected and ways I didn’t. The 52°F cold plunge is genuinely cold. I’d done cold showers before but sustained immersion at that temperature for 2-3 minutes is a different thing. The first session, I lasted 90 seconds before getting out. By day 5, I was completing the full 3 minutes.

What surprised me in the first two weeks was the mental state after sessions. I track mood and energy subjectively in my running spreadsheet, mostly as qualitative notes. After contrast therapy sessions, I consistently rated energy at 8-9 out of 10 for the following 4-6 hours — higher than my average. This tracks with the norepinephrine response that cold exposure reliably produces: (norepinephrine is a neurotransmitter and hormone that drives alertness, focus, and mood elevation — cold exposure increases it dramatically) norepinephrine spikes during and after cold immersion, then gradually returns to baseline over several hours.

Oura HRV during weeks 1-2 was variable. Several days in the first week showed slightly lower HRV than baseline, consistent with the adaptation stress of a new protocol. By week 2, HRV had stabilized above baseline and was trending upward.

Week 3–4: The Numbers Move

By week 3, the protocol felt integrated. No more dreading the cold plunge — it had shifted from an ordeal to something I was genuinely looking forward to, which I attribute to the dopamine baseline reset that regular cold exposure is supposed to produce. Whether that’s mechanism or placebo, the subjective experience was real.

My running averages, tracked by Oura:

Week	HRV avg (ms)	Deep sleep avg (min)	Resting HR avg (bpm)
Week 0 (prior 30 days)	58	102	52
Week 1	54	99	53
Week 2	60	103	51
Week 3	64	106	50
Week 4	67	108	49

Week 1 dip is normal adaptation stress. The trend from week 2 onward was consistent in the direction I was hoping for.

Day 30 Results

Marker	Day 0	Day 30	Change
IGF-1	224 ng/mL	248 ng/mL	+24 (+11%)
HRV (30-day avg)	58 ms	67 ms	+9 (+16%)
Deep sleep avg	102 min	108 min	+6 (+6%)
Total T	682 ng/dL	698 ng/dL	+16 (+2%)
Free T	19.4 pg/mL	20.1 pg/mL	+0.7 (+4%)
Resting HR avg	52 bpm	49 bpm	-3 (-6%)

The T moves are within normal variation — I wouldn’t read much into a 2% change over 30 days. The IGF-1 move of +24 ng/mL in 30 days is the piece I find most interesting. When I asked Ron about this, his reaction was measured: “That’s a real move if your other variables didn’t change, but 30 days is short and I’d want to see it replicate.” He’s right to be cautious. I ran one cycle. One data point isn’t a pattern.

What I think is driving the IGF-1 improvement: the (heat shock proteins, produced by cells in response to thermal stress, which assist in protein folding and appear to support GH secretory function) heat shock protein response from sauna is one mechanism. Improved deep sleep — even 6 more minutes per night on average — contributes to the nocturnal GH pulse, which is the largest GH secretory event in any 24-hour period. And better HRV, as a proxy for reduced sympathetic tone, may be creating a more favorable environment for GH pulsatility generally.

That’s consistent with what Ron lays out in his IGF-1 piece — the drivers of low IGF-1 are suppressive factors (visceral fat, broken sleep, insulin dysregulation, cortisol), and removing any suppressor allows IGF-1 to rise. If contrast therapy is reducing sympathetic tone and improving sleep architecture marginally, it may be pulling a small suppressive factor off the signal.

What I Got Wrong

I underestimated the time commitment. Three sauna sessions plus two additional cold sessions per week adds up to roughly 90-120 minutes of protocol time — not counting commute to the gym facility. During the weeks when my work schedule compressed, I missed sessions and the Oura data shows it: lower HRV on those weeks compared to weeks with full compliance.

I also expected the BAT (brown adipose tissue) activation from cold exposure to show up in some kind of body composition change. It didn’t. (Brown adipose tissue is a type of fat that generates heat by burning calories — cold exposure activates it, but the caloric effect at realistic exposure times is modest) Thirty days isn’t enough time for meaningful BAT adaptation, and the caloric burn from cold thermogenesis at 3 minutes per session is not significant enough to move the scale. I knew this intellectually going in, but I’d still half-hoped to see something. Nothing moved on body composition.

How to Actually Use This

Based on my 30 days and everything I understand about the mechanism, here’s how I’d structure contrast therapy protocol relative to your other work:

The Honest Breakdown

Tier 1 (free, do these first): Sleep architecture optimization. Structured training with lactate stimulus (the 6-12-25 Method, or any consistent moderate-intensity compound work). Insulin management. These move IGF-1 far more than contrast therapy does. Don’t skip to sauna and cold if sleep is still broken.

Tier 2 (add once Tier 1 is locked): Regular sauna 2-3x per week. Temperature 170-185°F, 15-20 minutes. Consistent enough to build heat shock protein adaptation over weeks, not a one-off.

Tier 3 (add once Tier 2 is consistent): Cold plunge immediately following sauna. Build from 60-90 seconds toward 2-3 minutes over your first two weeks. Hit the Søberg minimum of 11 cumulative minutes cold per week across your sessions.

Tier 4 (don’t bother until the earlier tiers are solid): Cold plunge only, no sauna, on off-days for additional cold exposure. This is what I added as a fifth session, and its marginal benefit over the three sauna+cold sessions is small. Get the primary sessions right first.

Things My Friends All Wanted to Know

Does cold plunge blunt muscle gains? If you do it immediately post-strength training, the answer is yes — it appears to reduce the hypertrophic signaling response. Keep 3-4 hours between your lifting session and cold plunge, or put them on separate days. I trained in the morning, went to the sauna/cold in the afternoon or evening.

How cold does the cold plunge need to be? The Søberg protocol research was done at temperatures below 60°F (15°C). Most commercial cold plunges run 50-58°F. Colder isn’t necessarily better — more important is the sustained exposure time. 3 minutes at 55°F produces a stronger norepinephrine response than 30 seconds at 45°F.

Can I use cold showers instead? For the norepinephrine and mood benefits, cold shower finishes work reasonably well. For the full contrast therapy protocol I ran, you need sustained whole-body cold immersion — the physiological response to a cold shower is meaningfully smaller than full cold plunge immersion.

Will this work if my IGF-1 is already optimized? It worked for me, but I started from a higher floor than most. If your IGF-1 is at 80 ng/mL, fix sleep, training, and body composition before testing contrast therapy. The marginal gain from sauna/cold when primary suppressors are still active is too small to be worth optimizing.

Is infrared sauna equivalent? Different mechanism. Infrared sauna heats core body temperature without the same convective heat stress that drives heat shock protein production in Finnish-style sauna. Both have cardiovascular and HRV benefits. For the heat shock protein GH mechanism specifically, the higher ambient temperatures of traditional sauna appear more relevant.

What Actually Moved the Needle

Thirty days. IGF-1 up 11%. HRV up 16%. Sleep minutes up slightly. Total T essentially flat. The contrast therapy protocol produced real but modest gains on a foundation that was already solid.

That framing matters. This isn’t a protocol for men starting from baseline suppression. It’s a protocol for men who’ve done the foundational sleep and training work and are looking for secondary edges. If you’re in that position, I think it’s worth the time investment. If you’re not in that position, spend the 90 minutes per week on sleep consistency instead.

I’ll retest IGF-1 at 90 days after adding a second month of the protocol. If the +24 ng/mL holds or extends, that’s a meaningful long-term finding. If it reverts, that tells me the 30-day signal was adaptation noise. Either way, the data will be more interesting than my one-month reading.

For now: the sauna is genuinely enjoyable, the cold plunge has become something I look forward to, and my Oura scores are at their highest average since I started tracking. Whether the IGF-1 move replicates or not, I’ll take the 30-day version of this.