Dr. Andy Galpin on Building Strength, Muscle Size and Endurance: Protocols, Hydration, Recovery and Supplements

High-Level Overview

Andrew Huberman sits down with Dr. Andy Galpin, a professor of kinesiology at California State University, Fullerton, who works everywhere from muscle biopsies under the microscope to training professional athletes. The conversation is a master class in how to train for strength, muscle growth (hypertrophy) and several kinds of endurance, built on a small set of principles and a handful of "modifiable variables" anyone can adjust. Galpin gives concrete sets, reps, rest periods and weekly structures, then moves into the mind-muscle connection, breathing, hydration (including what Huberman calls the Galpin equation), cold and heat exposure, tracking recovery, and supplements like creatine and sodium bicarbonate.

The tone is energetic, nerdy and frequently funny, with friendly muscle-guy versus nerve-guy ribbing between the two. Galpin is careful to separate solid research from preliminary findings and personal experience. The conversation builds from general principles to specific protocols, then widens into the lifestyle factors that support training.

The Discussion Explores:

• The nine adaptations exercise can produce, and why progressive overload is required for all of them
• The modifiable variables: exercise choice, intensity, volume, rest, progression and frequency
• Specific protocols for strength and power (the "three to five concept") and for hypertrophy (5 to 30 reps to near failure)
• The mind-muscle connection, learning to activate stubborn muscles, and bracing the core
• Breathing during lifts and a short down-regulation routine after training
• A weekly endurance structure, the interference effect, and why muscular endurance protects joints
• Hydration and sodium, cold and heat exposure, and how to track recovery
• Sodium bicarbonate, beta-alanine, creatine, and a new sleep diagnostic called Absolute Rest

Deep Dive into Main Ideas

Nine Adaptations and the Law of Progressive Overload

Galpin says "the concepts are actually fairly few, but the methods are many." He lists nine adaptations exercise can produce, in a deliberate order: skill, speed, power (strength multiplied by speed), strength, hypertrophy, muscular endurance, anaerobic power (hard work lasting roughly 30 seconds to two minutes), VO2 max (roughly three to 12 minutes) and long-duration endurance (30 minutes or more without a break). Fat loss is a byproduct, not an adaptation. Some of these carry over to each other, and some work against each other.

One rule applies to all of them: progressive overload. Adaptation happens as a response to stress, so repeating the same workout indefinitely will maintain fitness but not improve it. Overload can come from more weight, more reps, more frequent sessions, or more complexity, such as moving from a partial to a full range of motion, or from a machine exercise to a whole-body movement.

The Modifiable Variables, and Why Exercises Don't Determine Results

Galpin has a few "laws of strength and conditioning. One is that your exercises themselves do not determine adaptations": a bench press can build strength or muscular endurance depending on how it's done, so the sets, reps and rest matter more than the exercise itself. The variables he adjusts are exercise choice, intensity (a percentage of your one-rep max or max heart rate, not how hard it felt), volume (sets times reps), rest intervals, progression, and frequency. Beginners without a coach should choose technically simpler options, like a goblet squat, split squat or machines, over a barbell back squat.

You don't need to test your one-rep max; conversion charts can estimate it from a heavy set of several reps, or you can go by feel. He calls soreness "a terrible proxy for exercise quality" and suggests aiming for about a three out of ten most of the time. You can train a sore muscle, but if you're too sore to sit on the couch, you went too hard and will lose total volume by missing sessions. Another of his laws is that the default should be all joints through their full range of motion across the week, with a neutral spine; research generally shows larger ranges of motion improve both strength and hypertrophy. A simple balanced workout includes an upper-body push, an upper-body pull (both horizontal and vertical over time), a lower-body push like a squat or lunge, and a lower-body hinge like a deadlift. He jokes that technically every muscle only pulls, since muscle can only contract.

Strength and Power: The Three to Five Concept

Citing Henneman's size principle, Galpin explains that the high-threshold motor units and fast-twitch fibers, which are preferentially lost with aging, are only recruited when the muscle must produce a lot of force. So strength training has to be heavy: generally above 85% of your one-rep max (lower works for less-trained people, and complete beginners improve from almost anything). That means about five reps per set or fewer, two or three working sets after a gradual warm-up, and two to four minutes of rest so fatigue doesn't cut the intensity. To save time, you can superset non-competing exercises, like bench press and deadlift; his lab found this costs only a tiny bit of strength gain.

Because strength gains are driven by intensity rather than muscle damage, strength work causes little soreness, and the same muscles can be trained as often as daily, which is why elite lifters squat nearly every day. Two sessions per muscle per week is a very effective minimum. Early strength gains are mostly neural (roughly the first four weeks), with changes in the muscle itself, connective tissue and even fiber angles following later. That's why strength and size are related but not the same: bodybuilders have more muscle than powerlifters but are not stronger.

His simple template is the "three to five concept": three to five exercises, three to five sets, three to five reps, three to five minutes of rest, three to five days a week. That ranges from a 20-minute workout three times a week to a much larger program. For power instead of strength, keep the structure but use lighter loads, around 40% to 70%, moved fast. Intent matters: trying to move the bar as fast as possible improves power more than moving it at the same speed without that intent.

Hypertrophy: Volume, Near-Failure and Variety

Hypertrophy is driven by volume rather than intensity. Galpin says the programming is "idiot proof" but "The work is hard, though": anywhere from about five to 30 reps per set produces similar growth, as long as sets are taken close to muscular failure (not necessarily to the point where a partner must rescue the bar). Recent meta-analyses suggest about 10 working sets per muscle group per week as a minimum, with 15 to 20 better and 20 to 25 for well-trained people. Because muscle protein synthesis runs 24 to 48 hours, training a muscle roughly every 48 to 72 hours works well. Waiting longer doesn't lose gains; it just misses opportunities, and it makes hitting the weekly volume harder. He encourages varying rep ranges for fun, since a set of 30 gives a huge pump and burn without much soreness.

The three likely drivers of growth are mechanical tension, muscle damage and metabolic stress (the burn), which helps explain why light-load blood flow restriction training works; Huberman notes proper cuffs are essential. Galpin shares a quick checklist credited to Mike Israetel: during training, did you feel the target muscle working, did you get a pump, and were you a bit sore the next day? If all three are zero, don't expect growth. A three on each is good, and around five is plenty. Huberman recounts his teenage phone sessions with Mike Mentzer and his high-intensity approach, and Galpin explains that very infrequent, all-out training works well for untrained people but isn't optimal for most.

The Mind-Muscle Connection and Activating Stubborn Muscles

Galpin agrees that focusing on moving the weight suits strength, while focusing on the working muscle suits hypertrophy. Early studies suggest that watching and concentrating on a muscle, like the biceps during curls, produces more growth at the same load, and flexing between sets may help too. He adds that a focused, shorter session beats grinding through a distracted one.

For years, as a college football player, he couldn't activate his lats or rhomboids and pulled with his biceps instead. His fixes: awareness and tactile cues, like a partner touching the muscle or saying "squeeze my finger" between the shoulder blades; visualizing the muscle contracting; and eccentric-only work, such as starting at the top of a pull-up and lowering slowly, then progressing to isometric holds and full reps over weeks or months. For a bent-over row, squeeze the shoulder blades first, then lift the elbows without bending them further. Eccentric work creates more force and usually more soreness, which he attributes more to calcium disruption and swelling than to micro-tears. A lifting belt worn slightly loose can actually increase core activation by giving feedback to push against. He describes a self-test from Brian Mackenzie: with hands on your waist, try to push out against your fingers at the front, the sides above the hip bones, and the back near the PSIS. Many people can't activate the back portion, which limits spinal stability. The goal is a cylinder of bracing at around 20% that you can hold while still breathing and talking.

Breathing During Lifts and Down-Regulating Afterward

If you can brace and breathe at the same time, breath timing matters less. A reasonable default is to hold your breath and brace during the lowering, riskiest part of a lift, then exhale during the second half of the lifting portion. Single reps need no breathing, while longer sets need a strategy, such as breathing every third rep.

Galpin's athletes all use deliberate breathing between rounds or innings, and after every session they do a down-regulation routine, often lying on their back in low light: exhales about twice as long as inhales, box breathing or similar. Huberman says adding five minutes of this after workouts sped up his recovery and eliminated an energy crash he used to get three or four hours later. Galpin says even three minutes, or doing it in the shower, is worthwhile, and a one-minute version helps after any intense stretch of work.

Endurance: A Weekly Structure and the Interference Effect

For endurance, he warns beginners about eccentric landing: running involves landing on one leg hundreds of times, which causes soreness and shin splints if tissue isn't ready. Start with mostly concentric activities like cycling, swimming, rowing, sled pushing or uphill walking, and progress slowly. Pick what you're proficient at and enjoy; mixing, say, 10 minutes each on a treadmill, bike and rower works fine. Conversational-pace movement is valuable, but Galpin doesn't even count it as exercise; it's general physical activity everyone needs much more of, and it can be done while walking during phone calls. For longer sessions, he likes going as hard as possible while breathing through the nose only.

On top of that, he wants two nodes. Once a week, get close to maximum heart rate (roughly 220 minus age, though that's very rough; his own is about 210). Something like 90 seconds of burpees or hard intervals will do it, ideally four to eight bouts, after a good warm-up; every other week is fine if weekly is too daunting. "If you understand the point, the point of physiological failure, then you understand the place of adaptation": someone whose legs give out needs different training from someone whose breathing gives out. Second, sustained hard work of two to six minutes (or four to 12) at around 80% effort with equal rest, like a runner's mile repeats or 800s, which may give the most cardiovascular benefit of all.

On combining cardio and lifting, he tells the story of Robert Hickson's 1980 study, prompted by losing strength while running in John Holloszy's lab, which found that adding endurance work blunted strength and size gains while adding strength work didn't hurt endurance. Later research into signaling pathways seemed to confirm it, but Galpin now thinks the "interference effect is sort of real, but it's probably greatly overblown." It mainly matters with high volumes, heavy eccentric exercise like running, a goal of maximal muscle growth, and insufficient calories. Zone 2 cardio barely interferes, and hard intervals may even complement hypertrophy, partly through lactate, which he calls a beneficial molecule. Huberman notes he saw interference only from two-hour Sunday runs, not from 30-minute runs.

Muscular endurance, like wall sits and planks, is essential for joint health. Postural, slow-twitch muscles, like the soleus in the calf (about 80% to 90% slow twitch) and spinal erectors, must work constantly without tiring. When they fatigue, joints drift out of position and the fast-twitch muscles take over, leading to nagging shoulder or back pain. This links to his final law: "There are no good or bad exercises. There's only good or bad application." Injuries come from being out of position, often due to too much volume, intensity or complexity. When something hurts, drop just below the threshold that aggravates it and keep training there, to build tissue tolerance and desensitize pain, rather than stopping entirely.

Hydration, Sodium and the Galpin Equation

Hydration follows a curve: too little is harmful, and too much can cause hyponatremia (low blood sodium). As a baseline, drink about half your body weight in pounds as ounces of fluid per day; coffee and tea count, and whole foods contain a lot of water. After exercise, replace 125% to 150% of the weight lost. During training, the Galpin equation is your body weight in pounds divided by 30, in ounces, every 15 to 20 minutes. As a simple rule, he suggests about 500 milligrams of sodium before and after training, more for heavy sweaters, and some sodium during long, hot sessions. Losing less than about 1% of body weight doesn't need a special plan. He mentions sweat testing through a lab patch (Levelen) or a cheaper Gatorade patch with an app, or checking whether a hat or headband shows a white salt line. He cautions that people with hypertension, obesity or other risk factors must be careful with salt, while many active people with clean diets feel better with more. Training fasted or fed is largely personal preference.

Cold, Heat and Tracking Recovery

Galpin, a longtime believer in deliberate cold exposure, says an ice bath immediately after hypertrophy training is detrimental to muscle growth, possibly around a 10% blunting or more for some people. Ideally wait at least about four hours, or do cold on off days or before training; cold showers are a much weaker stimulus. After endurance work, cold is less of a concern and may even help. He frames it as adaptation versus optimization: in a building phase you want the stress signal, while in season, when athletes need to recover for the next game, recovery takes priority. Morning cold drops heart rate variability (HRV) sharply at first, but it tends to rise above baseline over the next two to three hours. Moving in the water breaks up the warm boundary layer and makes the cold much more intense.

Heat after training may aid hypertrophy through blood flow, though data are limited. He warns against assuming molecular changes, like a 300% growth hormone spike, translate into equal real-world results, and stresses that sauna is valuable for health but not a substitute for exercise. Huberman does about 60 minutes of sauna a week in three sessions and loses significant water. Huberman's ideal: train, then heat, and do cold on off days or well away from training. For recovery tracking, Galpin's program separates visible stressors, hidden stressors and recovery capacity, and first looks for "performance anchors," saying it's better to "take your foot off the brake" than to press harder on the gas. Useful markers include morning grip strength, HRV, daily vertical jump, a finger-tapping test, and the carbon dioxide tolerance test, which he says his lab has studied in relation to anxiety in work not yet published. Whatever you measure, measure it consistently, ideally in the morning. Huberman adds Alia Crum's findings that false feedback about sleep can change performance, a reason to be cautious about device scores.

Supplements and Absolute Rest

Sodium bicarbonate (baking soda) buffers acid, since fatigue is usually signaled by falling pH long before fuel or oxygen run out. Galpin walks through energy metabolism to explain why lactate actually helps prevent fatigue. He suggests starting low, around a quarter to half a teaspoon in water, roughly 20 to 90 minutes before hard interval work (about 45 minutes as a rough standard), with a bathroom nearby because of possible stomach upset. Beta-alanine works similarly by raising carnosine, a buffer inside muscle. His top pick is creatine monohydrate, "the Michael Jordan of all supplementation", for its safety, low cost and effects across performance and, increasingly, brain and clinical research. Huberman takes five grams daily mainly for cognition.

Finally, Galpin describes Absolute Rest, a sleep diagnostic he helped build with Cody Burkhart and others. It looks at psychology, physiology (hormones like cortisol and melatonin), pathology via full polysomnography, and the bedroom environment (temperature, humidity, volatile organic compounds, allergens and the carbon dioxide cloud around the face). One professional athlete had about 280 breathing disruption episodes per night, mostly on his back; a simple positioning pillow cut them by 85% the first night, and his testosterone eventually tripled over three months.

Conclusion

Andy Galpin's framework makes training simpler than it looks: pick your goal, apply progressive overload, and adjust a few variables. For strength, lift heavy for low reps with long rest, often; for hypertrophy, do enough weekly sets of 5 to 30 reps close to failure; for endurance, move a lot, touch max heart rate about once a week, and include sustained hard efforts of a few minutes. Support it with full ranges of motion, good positions, deliberate breathing and a few minutes of calm after training, sound hydration and sodium, smart timing of cold and heat, consistent recovery tracking, and proven supplements like creatine. It's a long episode, but it's one of the most practical guides to training for anyone, from beginners to serious athletes.

This is a summary of "How to Build Strength, Muscle Size & Endurance | Dr. Andy Galpin" from Huberman Lab, giving you the GIST so you can decide if you want the REST. Listen to the full episode.