Physiologically Speaking

Greetings!In place of this week’s newsletter, I recorded a Q&A session based on questions I’ve received in the last few months. I had so much fun doing it and hope you enjoy listening (and learn something!)I answer a variety of questions related to training, nutrition, supplementation, and injury prevention; share insights on the use of ketones and creatine; discuss fueling strategies for workouts, and emphasize the importance of mental performance and adaptation. I also cover challenges related to heat training, health concerns associated with high training volumes, and the role of gear in running, as well as advice on weight management while training for performance.You can find an edited list of questions and my responses below (for those who prefer to read). It’s a bit shorter and punchier for better digestibility.Nutrition & SupplementationExogenous KetonesQ: How often do you use exogenous ketones? I noticed recovery benefits during ultra training but not with lower volume.A: During peak marathon blocks I currently take 4 shots/week (of Ketone-IQ: two after my hard interval session and two after my long run. I pair them with post‑workout carbs and protein. I generally don’t use them in base phases or at low training volumes.Q: What are your overall thoughts on ketones, and when/how often do you take them? Worth the investment?A: They’re not a miracle supplement, and many basics move the needle more. For me—solid sleep, nutrition, and training already in place—ketones are a small edge I experiment with mainly post‑workout for recovery. Cost matters, so I focus usage where I feel the most benefit.Q: Do you use ketones pre‑workout or pre‑race? I’ve heard folks tout recovery benefits most.A: Rarely pre‑race. Occasionally before a long run for a “flow”/focus feel, but for performance I prioritize carbohydrates during the session. My primary use case remains after hard sessions and long runs.CreatineQ: Thoughts on creatine? Do you cycle off?A: I take ~5–10 g/day, every day. There’s no need to cycle; creatine isn’t a hormone and doesn’t cause receptor “desensitization.” If you stop for a week or two, your stores remain fairly saturated; after >~1 month off, benefits likely wane.Q: Do you take creatine on non‑training days?A: Yes—daily. Creatine works via long‑term saturation, not acute timing.Q: Does timing matter?A: You can take it anytime, but I prefer post‑workout with a meal (protein + carbs). Better blood flow/insulin sensitivity may help uptake and support glycogen/protein synthesis.Q: What supplements are you taking right now?A: Daily: Omega‑3s (EPA/DHA), creatine, vitamin D, iron (FerroZorb/Thorne), and Tongkat Ali (experimental; no clear effects noticed, no downsides so far). I removed ashwagandha—I felt it sometimes blunted my drive/mood (anecdotal).FuelingQ: How do you fuel early‑morning sessions? Two‑hour rides are also hard to fuel.A: I’m not hungry early. I usually start fasted and then take carbs during (gels/drink mix). For 90–120 minutes, I aim ~40–60 g carbs/hour. ≤80‑minute easy runs I often do fasted.Q: What do you eat right after a workout if you’re not hungry?A: Hot days kill appetite. I lean on Greek yogurt + granola + berries or a smoothie (protein + fruit + greens powder + ice). Cold/sweet options go down easier than “hearty” meals.Q: You use multiple gel types. How do you choose, and why not Maurten?A: I rotate to avoid palate fatigue and to match purpose: caffeine vs. non‑caffeine; 40 g vs. 20–25 g carb gels; different carb sources (maltodextrin/fructose vs. “real‑food” blends). Current favorites:* SIS Beta Fuel (40 g, isotonic)—easy to take without water.* Minted (40 g + ~50 mg caffeine, unflavored)—simple profile.* BPN GO (25 g, real‑food)—tasty and lighter. Maurten works but the chewable texture isn’t ideal for me at race pace.Q: Benefits of fueling even “easy” long runs? Downsides of not fueling?A: Fueling easy long runs may not boost performance that day, but it protects recovery by limiting glycogen debt/calorie deficit. I feel better the next day when I fuel a 20‑miler vs. under‑fueling or going fully fasted.Training & WorkoutsQ: First six weeks of a 12‑week marathon block—what quality do you do? Continuous threshold or intervals? Key goal‑pace workout before race?A: Early and late phases look similar: lots of tempo/threshold work, with some shorter, faster reps closer to race day. I prefer continuous threshold (tempos; 2–3 mi repeats) over short reps. Two staples:* 8–10 miles at marathon pace within a long run (dress rehearsal with fueling/shoes).* 4–3–2–1 mile cut‑down (pace quickens each block; ~10 total quality miles).Q: Strength training—do you follow a program (e.g., StrengthLog)?A: Not a strict program. I do simple bodyweight/dumbbell work a few times weekly (push‑ups, pull‑ups, DB variations). It’s minimal but helps durability.Q: Go‑to bike workouts to improve running?A: Mostly aerobic intervals like 3–4 × 15–20 min @ ~80–85% FTP. Great marathon‑effort proxy. Otherwise lots of easy spinning to replace a Zone‑2 run.Q: Downsides of adding biking in a marathon block? Overtraining risk?A: It’s not a free lunch—still a stressor. I adjust cycling down if run volume rises. That said, easy rides can be low‑cost aerobic work or recovery.Q: Swimming instead of biking for cross‑training?A: Personal bias: I don’t enjoy swimming. It’s fine for fitness, but I find less direct transfer to running than cycling.Q: Bike vs. elliptical for cross‑training?A: Elliptical mimics upright mechanics better, but I can produce/measure higher quality work on the bike. Preference and ability to hit the intended load should decide; I still prefer the bike.Q: Are treadmill and pavement biomechanics different?A: Yes. Outdoors you propel over ground; on a treadmill the belt moves under you. Effort at a given pace often feels easier on the treadmill.Injury Prevention & RecoveryQ: How do you prevent injury with 12–15 hr/week of training?A: No magic: sensible load management, don’t go hard daily, keep form a priority, do some strength, and stay generally active/robust.Q: How do you decide whether to run with pain?A: I use a mental pain scale. If symptoms hit ≥4–5/10, persist after a few days off, or worsen, I shut it down and assess. Don’t push through vague pain that lingers (e.g., multi‑week hip pain)—get it checked.Mental Performance & AdaptationQ: Do you have a mental performance routine?A: Nothing formal. I practice self‑talk and “flow” during workouts. I also value training alone regularly to build self‑reliance for race discomfort.Q: Progress from fitness vs. pain tolerance—what’s mattered more lately?A: Both. I’m fitter and more efficient/durable. Durability = less decline late in races. Learning to sit with discomfort and read physiology (breathing/HR cues) has been huge.Heat & Environmental TrainingQ: How do you handle brutal Southern heat (Austin, TX)?A: Basics: start early, hydrate, fuel, dress smart, and adjust expectations. Use effort, not pace. Heat acclimation helps, but it never feels easy.Q: Should heat inputs (sauna, hot baths) be avoided on recovery days since heat is a stressor?A: Heat is real stress. Sometimes I substitute a workout with 30–45 min sauna on an easy day. Just count it in total load and listen to fatigue.Q: You log sauna sessions—do you count them as training time?A: Yes, but I don’t always adjust running unless overall load feels high. In Texas summers I often skip sauna—the daily outdoor heat load is plenty.Health & PhysiologyQ: Does high volume make you reconsider due to coronary calcification or AFib risk?A: I follow the research closely. AFib risk seems higher in longtime endurance athletes; coronary calcium findings are mixed and confounded. Personally, multiple cardiac tests have been normal. I’m 32 and will keep monitoring, but it hasn’t led me to avoid endurance training.Gear & EquipmentQ: Are “super shoes/trainers” just fun, or do they help on easy mileage too?A: They can reduce musculoskeletal load and may let you train more at lower cost if you run well in them. I wouldn’t use them 100% of the time, but ~75–80% of weekly mileage in super trainers can be reasonable for some runners.Q: How do you carry water on runs?A: In heat I use belts (e.g., Nathan; “Nerd Belt”) or a light running vest (CamelBak) with front bottles and storage. Handhelds work but I prefer hands‑free. I also plan routes with refill stops when possible.Weight Management & PerformanceQ: Can I lose ~30 lb while building mileage/speed for a January marathon, working full‑time?A: Possible, but performance fueling and caloric deficit are at odds. Two paths:* Concurrent, slow loss: ~200–500 kcal/day deficit (≈0.5 lb/week), prioritize carbs for training and protein for recovery.* Staggered approach (preferred for smaller losses): Lose weight in an off‑season, then train at maintenance for performance. Either way: gradual, protein‑forward, and performance‑aware.Training SymptomsQ: I feel shaky only on Zone‑2 runs despite “fueling well.” Why?A: I experienced this and traced it (via CGM) to reactive hypoglycemia from eating carbs ~20–30 min pre‑run. Insulin was peaking just as muscles were pulling in glucose, dropping blood sugar. Fixes that worked for me:* Start fasted, then take carbs ~20–30 min into the run; or* Eat ≥60 minutes before (or immediately before, if you tolerate it). Cycling vs. running differences may vary individually—experiment with timing. This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe

Dr. Nicholas Fabiano is a psychiatry resident at the University of Ottawa and a rising voice in the field of lifestyle psychiatry. With a background in applied life sciences and medical training at the University of Ottawa, he has developed a passion for understanding how exercise, nutrition, and sleep influence mental health.Featured in outlets such as The Washington Post and Fast Company, Dr. Fabiano has been recognized as a “rising star” in neuroscience for his evidence-based approach to mental health. In this conversation, Dr. Fabiano joins me to discuss the multifaceted role of creatine, particularly its implications for brain health, cognitive function, and mental health. We focus on a review article he just published titled "Creatine for the Brain: More is Likely Better for Brain Bioenergetics, Health, and Function,” in which he argues that 10 grams or more of creatine per day may be the optimal dose for cognitive performance and mental health.He emphasizes the importance of understanding dosing, the potential benefits of creatine in various conditions such as sleep deprivation, traumatic brain injury, Alzheimer's disease, and depression, and the need for more research to optimize creatine supplementation and its mechanisms of action in the brain.Follow Nick on X: @ntfabianoFollow Nick on Instagram: @ntfabiano This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe

On Monday, I spoke to the Bone Health & Osteoporosis Foundation's ‘Be Bone Strong’ NYC & Sydney Marathon Teams for an in-depth discussion on how to train smarter, recover better, and boost performance at any age.Thanks to Barbara Grufferman for the invitation and opportunity to speak. She’s graciously allowed me to share the webinar with my audience. Enjoy!Topics covered:* Recovery after stress fractures * Flexible training strategies that protect performance * How to improve speed without risking injury * Pacing tips for race day success * Age-related adaptations and smarter recovery for older runners * Heat training and travel prep for international races * Creatine: what kind, how much, and when to take it * Nutrition timing for energy and performance * Electrolytes, hydration, and marathon fueling * Pros and cons of ice baths, compression boots, and NSAIDs * VO₂ max: what it is and how to raise it * Why "physiological resilience" matters * Sleep, glycogen, and why gels matter mid-race* And more! This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe

Welcome to the recap of my first live subscriber Q&A! It was a lot of fun connecting with you all and answering your thoughtful questions. In this post, I’ll walk through the key topics we discussed, including my marathon training approach, supplement routine, fueling strategies, and more.Thank you Zach Bitter, Esther VanderMark, dr_cois, Barbell Mentality, and many others for tuning into my live video! Join me for my next live video in the app.Table of contents* My Training Philosophy: Running Less, Biking More* My Supplement Routine (and Philosophy)* Fueling for Long Runs and Marathons: How I Changed My Approach* Live Q&A Questions* Have you experienced low blood sugar or bonking during runs?* What’s your advice for returning to running after an injury?* Does cycling help build your aerobic base for running?* What are your thoughts on nitrate supplements like beetroot juice?* What’s your approach to warming up before races and workouts?* Do you lift after long runs or interval workouts?* What do you think about concerns over eating high amounts of carbs during marathons?* How does race-day nutrition affect your recovery afterward?* If I’m a slower marathoner, should I train differently than you?* What’s your approach to returning to training after illness?* Is cycling useful even if your running mileage isn’t maxed out yet?* How does L-glutamine help with gut health?My Training Philosophy: Running Less, Biking MoreOne of the most common questions I get is about how I structure my training week, particularly how I balance running and cycling. For my Boston Marathon build, I chose to run five days per week and ride the bike two days per week. This approach stems from years of battling injuries, particularly bone stress injuries. Every time I tried running six or seven days per week—even at moderate mileage—I seemed to get hurt.To avoid that, I started squeezing more mileage into fewer running days, reaching 75 to 85 miles per week while running just five days. On the two non-running days, I cycled for 90 minutes to two and a half hours using Zwift. Cycling allowed me to maintain a high aerobic load without the musculoskeletal strain of running. Having two full days without running each week seemed to give my body the time it needed to recover and regenerate. I felt fresher on all my runs and stayed injury-free throughout the training block, which hadn't been the case in past training cycles.My Supplement Routine (and Philosophy)Supplements are something I get asked about all the time, and during the Q&A, I walked through my current supplement stack. I take a fairly extensive range of supplements, but my general philosophy is simple: if you have the discretionary income and a curiosity to experiment, supplements can be worth exploring.Each morning, I start with a whey protein shake, usually mixing 20 to 30 grams of whey protein with almond milk. I add a greens and probiotic powder, and I take L-glutamine daily, mostly for gut health and immune support. Creatine monohydrate is also a daily staple, as is an omega-3 supplement, iron (to correct low ferritin), and vitamin D3. I also occasionally use ashwagandha to support stress adaptation. Supplements aren’t magic, but they can help support an already solid foundation of training, nutrition, and sleep.Fueling for Long Runs and Marathons: How I Changed My ApproachFueling during training runs and races has been one of the biggest shifts in my approach over the past year. Previously, I barely fueled during runs, often going fasted. Now, for most morning runs, I eat a small snack about 30 to 45 minutes beforehand. During long runs or runs over 90 minutes, I take energy gels every 30 to 40 minutes. Science in Sport Beta Fuel gels have been my favorite because of their high carbohydrate content and easy consistency.Proper fueling has made a noticeable difference not just in performance but also in recovery. By ending long workouts with a smaller energy deficit, my next-day performance has been consistently better.Live Q&A QuestionsHave you experienced low blood sugar or bonking during runs?Yes, especially after I started eating before runs. I experienced mild reactive hypoglycemia about three miles into runs, which I confirmed using a continuous glucose monitor. It turned out the timing of my pre-run snack was causing a dip in blood sugar. Adjusting the timing—either eating earlier (45–60 minutes before) or just minutes before starting—helped eliminate the issue.What’s your advice for returning to running after an injury?I recommend the walk-run method, regardless of experience level. Coming back slowly with a run-walk protocol reduces injury risk and helps you rebuild fitness without overwhelming your musculoskeletal system. Even elite runners use this strategy when returning from time off.Does cycling help build your aerobic base for running?Absolutely. Cycling has been a key part of maintaining and building my aerobic fitness while sparing my body from the pounding of running. Two days of cycling per week allowed me to maintain a high training load without increasing injury risk during my Boston build.What are your thoughts on nitrate supplements like beetroot juice?Nitrate supplements have strong evidence for enhancing performance, especially in clinical or less-trained populations. For highly trained athletes, the benefits are likely smaller but still potentially meaningful. They are safe and can also support cardiovascular health, so if you're curious, they are worth trying.What’s your approach to warming up before races and workouts?I’m a big believer in long, extensive warmups—typically 4–6 miles of easy running with some race-pace surges. You want to feel warm and ready when the race starts, not spend the first few miles getting into rhythm. A proper warmup can make a big difference in early race pacing and overall performance.Do you lift after long runs or interval workouts?Yes, but strategically. I usually lift after my Sunday long runs because it’s easier to stack hard efforts on the same day and allow easier recovery days afterward. I do my best to get into the gym immediately after the run while I’m still warm, even though it's not always easy.What do you think about concerns over eating high amounts of carbs during marathons?I think it's mostly fear-mongering. Race-day fueling is not the same as everyday eating. Consuming 80 grams of carbohydrates per hour during a marathon is performance-enhancing and supports recovery. There’s no strong evidence that race-day carb intake leads to metabolic disease when your daily nutrition is solid.How does race-day nutrition affect your recovery afterward?Proper fueling during the race has a huge impact on how you feel in the days afterward. After Boston, although I still had muscle soreness, my recovery was far smoother compared to previous marathons. I believe fueling adequately during the race played a major role in that.If I’m a slower marathoner (around four hours), should I train differently than you?Not drastically. You don’t need to run more hours per week, but your long runs should probably be longer in duration compared to mine. I would recommend aiming for three to three and a half hour long runs, even if your weekly mileage stays relatively modest.What’s your approach to returning to training after illness?Slow and steady. I focus first on building back volume at low intensity and delay introducing intensity until I feel fully recovered. Low-intensity walking, biking, or easy running can be good first steps before resuming hard efforts.Is cycling useful even if your running mileage isn’t maxed out yet?Definitely. Cycling can be a supplement to running even if you’re not at your maximum running volume. It’s an excellent tool to add more aerobic training stress without the same injury risks as running.How does L-glutamine help with gut health?L-glutamine may help support the gut lining and reduce gastrointestinal permeability, especially important during periods of heavy training or exercising in the heat. I’ve added it recently to help support digestion during intense marathon training blocks.Final ThoughtsThis Q&A was a blast. I’m so grateful for everyone who tuned in, asked thoughtful questions, and stayed engaged throughout the session. Going forward, I’m considering doing more Q&A sessions, maybe focused more narrowly on specific topics like fueling strategies, supplements, or injury prevention.If you have any feedback or ideas for future Q&As, I’d love to hear them. Thanks again for being part of this awesome community. I'll see you next time—whether it’s here, on X, or maybe even in real life! This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe

In this episode, I sit down with Brian Heiderscheit , a professor in the Department of Orthopedics and Rehabilitation at the University of Wisconsin-Madison and director of the Badger Athletic Performance program. Brian also collaborates with Springbok Analytics, a company specializing in advanced full-body MRI scans. Together, we discuss my recent experience with a Springbok scan, how MRI data is revolutionizing athlete performance analysis, and actionable insights for reducing injury risks and improving training outcomes.Key Topics Covered:* Introduction to Springbok Analytics: Overview of their advanced MRI technology and its application in research and athletic training.* Brian’s Background: Insights into his role at UW-Madison and collaborations with Springbok Analytics on research initiatives, including a grant with the NFL.* My MRI Experience:* The scanning process, which takes 10-15 minutes.* Analysis of over 74 muscles rendered in 3D.* Comparison to population norms and evaluation of muscle size, asymmetry, and fat infiltration.* Key Findings from My Scan:* Notable asymmetry in muscle size between the left and right legs.* Larger left-side muscles, likely due to targeted rehabilitation post-injury. My left semitendinosus and other hamstrings were larger, while the right biceps femoris was bigger by about 10%.* Smaller right-side plantar flexors (e.g., soleus, gastroc) compared to the left, with a 7% size difference in the soleus. These findings align with subjective feelings of less power on the right side during runs.* My quadriceps showed strong development, particularly on the left, with right-side muscles slightly smaller.* Fat infiltration analysis, showing low levels typical of an active individual, with slight increases in the quadratus lumborum.* Actionable Insights for Athletes:* Targeted strength training to address imbalances, particularly focusing on the right-side soleus and quadriceps.* The potential value of pairing MRI data with gait analysis for a comprehensive view of biomechanics.* Using follow-up scans to evaluate the effectiveness of training programs.* The Role of MRI in Longitudinal Tracking:* Establishing a baseline for future comparison.* Monitoring recovery from injury or changes in training plans.* Brian’s Recommendations:* Adjust training to improve right-side strength, especially in the soleus and hamstrings.* Consider integrating gait analysis to identify asymmetries during running.Resources Mentioned:* Springbok Analytics: springbokanalytics.com* Badger Athletic Performance Program: BAP at UW-Madison* Brian Hederscheidt’s Google Scholar Profile for published research This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe

Greetings!Happy Black Friday to those who celebrate.Are you looking for a new health, fitness, or nutrition product for yourself or to give as a gift to family and friends? Here are a few Black Friday/Cyber Monday deals from brands I’m affiliated with and use myself.Save up to 60% on an Examine.com membershipGet 30% off of your Ketone-IQ purchase30% off of FSTFUEL electrolytes with the code BRADY30 at checkout30% off of Presleep sleep supplement with the code BRADY30 at checkout10% off of a Pedal Industries Race Day bag with the code INF-BRADY at checkoutGet Decaf Drip coffeeAdditionally, for a limited time, you can snag a yearly subscription to Physiologically Speaking for $39.99 (originally $50) or purchase a subscription for a friend or family member as a gift.Physiologically Speaking is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber.Today, instead of a new study, I’m sharing the video of a podcast appearance I made on The Mind Muscle Connection with Jeff Hoehn.We talk about:* Research* Endurance exercise performance* Sleep* Training & nutrition* Supplements* Cardio* Recovery* Calorie intake* Metabolism* Aerobic exercise training* Exercise volume and intensity* How to measure improvements in cardiovascular fitness* My 7 rules for health* And more!* Be sure to check out Jeff’s podcast, subscribe, and give him a follow on Instagram and X.Thanks so much for subscribing. I’m grateful to every one of my audience members!~Brady~ This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.physiologicallyspeaking.com/subscribe