Huberman Lab Essentials: How to Exercise for Strength Gains & Hormone Optimization

Guest: Dr. Duncan French | Host: Dr. Andrew Huberman
Date: September 18, 2025

Episode Overview

This Essentials episode of the Huberman Lab podcast, hosted by Dr. Andrew Huberman, features Dr. Duncan French, an expert in strength training and endocrine responses. They dive deep into the science of resistance training for strength, hypertrophy, and hormonal optimization, with a special focus on maximizing testosterone, growth hormone, and the balance between metabolic and mechanical stress. The discussion blends practical protocols for athletes and everyday people, the interplay of stress and adaptation, strategic use of cold and heat, and the nuanced role of nutrition.

Key Discussion Points & Insights

1. Hormonal Response to Resistance Training

• Testosterone Release Pathways

  • Heavy resistance training triggers a stress response (mechanical + metabolic) signaling the endocrine system to release testosterone.

  • Both adrenal glands and gonads (testes) are involved in men; women’s increases in testosterone post-training are solely adrenal.

  • The acute (short-term) response mainly involves adrenal secretion, while chronic adaptation is more gonadal.

  • Quote:
    "It's a stress response, right? It's mechanical stress and it's metabolic stress...downstream regulation of testosterone release at the gonads comes from many different areas."
    — Dr. Duncan French (00:54)

• Testosterone Effects Beyond Muscle

  • Testosterone also enhances tendon, ligament, and bone health, not just muscle.

  • Androgen receptors are found on neural tissue, highlighting testosterone’s system-wide impact.

  • Quote:
    "There's androgen receptors on neural tissue, on neural axons pretty much everywhere... it's a magic hormone, let's say, with many end impacts."
    — Dr. Duncan French (03:55)

2. Optimal Weight Training Protocols

• Protocol for Maximum Testosterone

  • Six sets of ten repetitions (6x10), at 80% of one-rep max, with 2-minute rests.

  • Intensity and sufficient volume are both key for stimulating testosterone.

  • If intensity drops too much in high volume (e.g. classic 10x10), reduce volume to maintain intensity.

  • Quote:
    "It's an intensity and a volume derivative that is going to be most advantageous for testosterone release."
    — Dr. Duncan French (06:05)

• The Importance of Metabolic Stress

  • Shorter rest intervals (e.g., 2 min vs 3 min) promote higher metabolic stress and greater muscle gains.

  • The intensity-volume balance is critical; too much volume with insufficient intensity is counterproductive.

  • Quote:
    "The rest is as important a programming variable as the load and the intensity... if you extend the duration of your rest periods, what you're ultimately doing is influencing that metabolic stimulus."
    — Dr. Duncan French (07:58)

3. Training Frequency & Recovery

• Intense, short, metabolically stressful workouts (like 6x10) are best performed 2x/week for most non-elite individuals.

• Other sessions in the week can vary in rep ranges and intensity to support recovery and adaptation.

  • Quote:
    "A protocol like that we would look at two times a week, something that's pretty intensive like that ...because again, you really need to be, for, want a better term, suffering a little bit through that type of protocol…"
    — Dr. Duncan French (11:15)

4. Acute Stress, Hormones, and Mindset

• Short-term, intense stress (e.g., high-intensity exercise or even skydiving) can acutely increase testosterone.

• The psychological interpretation of the stressor (voluntary vs. involuntary) affects hormonal response.

• Pre-arousal and psychological preparation before an event amplify the endocrine and performance response.

  • Quote:
    "From my data, certainly the greater arousal, the higher the performance was. From a physical exertion perspective, there's definitely an individual biokinetics to some of these hormonal kind of releases..."
    — Dr. Duncan French (14:27)

5. Cold Exposure for Recovery: Strategic Use

• Cold exposure (ice baths, cold showers) elicits a stress response similar to intense exercise.
• Cold can dampen muscle growth by interfering with inflammation and mTOR signaling; thus, it should be timed strategically.

  • Avoid during periods when muscle hypertrophy and adaptation are the goal.

  • More useful during competition phases focused on recovery and technical skill, not growth.

  • Quote:
    "It's probably not the most beneficial approach to use an ice bath in that scenario because you're dampening... the hypertrophic signaling pathway. Whereas in a competition phase... you want to throw the kitchen sink of recovery capabilities..."
    — Dr. Duncan French (17:25)

6. Education and Personalization in Athlete Recovery

• Top athletes and teams are increasingly educated about optimal timing of cold and other modalities.

• The best athletes are those who can recover and perform repeatedly due to smart, periodized use of training and recovery interventions.

  • Quote:
    "The most elite level, you're not necessarily training harder... but the best athletes... can do it again and again and again on a daily basis and sustain a technical output for skill development."
    — Dr. Duncan French (21:29)

7. Skill Acquisition: Quality over Quantity

• Short, high-quality training sessions (90 minutes or less) are superior for learning skills compared to longer, fatiguing sessions.

• Cognitive fatigue from intense focus on technique also requires proper fueling (glucose) and rest.

  • Quote:
    "It's a quality driven exercise... as soon as that becomes impacted by fatigue or inaccurate movement, you're now losing the motor learning."
    — Dr. Duncan French (24:04)

8. Nutrition, Fueling, and Metabolic Efficiency

• High-intensity athletes generally require carbohydrate fueling; full ketogenic diets are rarely suitable for such sports.

• For metabolic efficiency, periodize carbs: use low-carb or ketogenic meals outside training, and time carb intake pre-, during, and post-high intensity sessions.

• Teaching the body to use fats during low-intensity activity and carbohydrates for intense work prevents premature fatigue.

  • Quote:
    "If athletes or any individual has a high carbohydrate diet, they're going to start to become predisposed to utilizing that fuel source preferentially...if they preferentially use carbohydrate at lower intensities... they've already exhausted their fuel stores."
    — Dr. Duncan French (30:04)

9. Heat Adaptation & Performance

• Heat acclimation protocols (sauna) should begin 8-10 weeks before a target event.

• Start with 15-minute exposures and build up to 30–45 minutes over 14 sessions to improve sweating and thermoregulatory adaptation.

  • Quote:
    "We try to work up to 30 to 40 minutes to 45 minutes in the sauna continuous...about 14 sauna exposures starts to really then drive the adaptations that we're looking for."
    — Dr. Duncan French (35:00)

10. Individualization & Tracking Progress

• Body adaptations to training or diet interventions typically become apparent within 12 weeks, but individual responses vary.

• Self-tracking (logs, journals) is critical for optimizing one’s own regimen.

  • Quote:
    "You have to consciously understand where your body's at any moment in time... create a journal, create a log of your training, create a log of your feelings, your subjective feedback..."
    — Dr. Duncan French (37:36)

Memorable Quotes & Moments

• Testosterone and Adaptation:
  "Testosterone is a magic hormone, let's say, with many end impacts."
  — Duncan French (03:55)

• Acute Stress Benefits:
  "So stress can promote the release of testosterone. That was news to me."
  — Andrew Huberman (12:57)

• Importance of Mindful Rest:
  "Rest is as important a programming variable as the load and the intensity."
  — Duncan French (07:58)

• Skill Learning Mindset:
  "Shorter sessions that are very high quality... we'll take the 90 minute session any day when it comes to skill acquisition."
  — Duncan French (24:04)

• Customization:
  "We could put 15 guys on the mat and give them the same workout, and there's going to be 15 different responses to that same workout, because the human organism is so complex..."
  — Duncan French (38:19)

Timestamps for Key Segments

• Testosterone & Hormonal Effects: 00:29 – 05:43
• Optimal Workouts for Anabolic Response: 05:26 – 08:34
• Training Intensity, Volume, and Recovery: 08:29 – 12:34
• Acute Stress & Hormonal Implications: 12:34 – 15:04
• Cold Exposure: Recovery vs Hypertrophy: 15:04 – 22:12
• High-Performance Athlete Recovery Strategies: 20:05 – 22:12
• Skill Learning & Cognitive Fatigue: 23:53 – 26:19
• Fueling and Metabolic Flexibility: 26:19 – 32:33
• Heat Acclimation Protocols: 34:15 – 36:31
• Adaptation & Self-Tracking: 37:13 – 39:06

Summary Takeaways

• Effective training for strength and hormone optimization balances high intensity, adequate volume, and short rest.
• Acute stress boosts testosterone and performance—mental framing matters.
• Cold therapy can blunt growth—use it strategically only during phases prioritizing recovery/skill over hypertrophy.
• Nutrition should be periodized and timed based on training demands and intensity.
• Adaptation to both physical and dietary interventions is highly individual—track, review, and adjust.
• Skill training: prioritize frequent, short, high-quality sessions rather than long, fatiguing workouts.
• Heat acclimation is achievable and enhances athletic weight-cutting and thermoregulation; it requires at least 14 exposures for adaptation.
• The "thinking athlete" who logs and reflects on their process will make the most progress.