The Endurance Lab

Anar Larsson from Tymewear explains why heart rate, pace, power, and even lactate can mislead runners when trying to find their real physiological Zone 2. They often end up training in Zone 3 instead. We talk about VT1, VT2, ventilation, fat oxidation, durability, and why many endurance athletes accidentally train too hard even when they think they are doing easy aerobic training.

🫁 Save $100 on Tymewear Pro Training Membership
Code: E-LABTW26
👉 https://www.tymewear.com/E-LABTW26

🫁 10% off Isocapnic BWB DeviceCode: JusmanSo
👉 https://shop.isocapnic.com?sca_ref=10462834.lsRLwaoT7WUNdYI

🏃 5K, 10K, Half & Full Marathon Training Plans
👉 https://theendurancelab.run/training-plans

🎓 Exclusive Discounts & Resources👉 https://theendurancelab.run/exclusive-discounts

In this episode:
• Why many runners are not really in Zone 2
• Why heart rate can drift without your physiology changing
• Why ventilation may be a better marker of intensity
• How VT1 and VT2 define your real training zones
• Why fat oxidation matters for endurance performance
• How to improve durability and delay fatigue
• Why breathing muscles can be trained
• How Tymewear Vital Pro measures ventilation in real time

Connect with The Endurance Lab:
📩 Email: jusman@theendurancelab.run

Chapters:
00:00 Are You Really Zone 2?
03:00 What Zone 2 Means
06:02 Ventilation vs Lactate
10:32 Why Heart Rate Misleads
15:20 Measuring Physiological State
22:25 Why Generic Zones Fail
26:25 Power Needs Physiology
29:11 Zone 3 Stagnation
30:17 Anar’s Background
34:00 Ventilation as Ground Truth
37:39 Ventilation vs Heart Rate
39:41 How Tymewear Measures Breathing
45:26 Finding VT1 and VT2
50:59 Where Ventilation Fails
56:04 Breathing Rate vs Tidal Volume
58:36 Tymewear Vital Pro
1:03:57 Training in Heat
1:07:49 What Is Durability?
1:11:28 Other Real-Time Tools
1:13:48 Stress and Breathing
1:14:54 Training Breathing Muscles
1:17:13 ISOCapnic BWB

#runningover40 #marathontraining #zonetwotraining #heartratetraining #endurancetraining

Most runners think about training in terms of mileage, intervals, and long runs. Very few think about heat as a performance tool. But heat training could be one of the most accessible and evidence-based performance levers available to any recreational runner — and it requires no extra miles, no gym membership, and no expensive equipment.In this episode
Dr. Daniel Snape — sports scientist, environmental physiologist, and the researcher behind the heat and altitude programs for 2025 UTMB winners Tom Evans and Ruth Croft — breaks down exactly how heat training works, what it does to your body, and how any runner over 40 can use it to run faster at a lower heart rate without adding more mileage or intensity to their week.
Whether you have access to a sauna, a hot bath, or just a treadmill and some extra layers, this episode will change how you think about what counts as training.

Customised heat and hypoxic training programs by Dr. Daniel Snape and his team at Leeds Beckett University Health and Performance Hub:
https://www.leedsbeckett.ac.uk/carnegie-school-of-sport/health-and-performance-hub/

0:00 Run faster at the same heart rate
4:00 Heat training vs heat acclimatisation
8:10 What temperatures are we actually targeting
9:51 Plasma volume — what it is and what heat training does to it
11:14 Hematocrit and red blood cells explained
13:44 Does heat training affect the heart
15:01 What training zone are you actually in during a heat session
16:32 How heat training changes your sweat response
18:54 Core temperature and performance range
20:07 VO2 max — how much does heat training actually increase it
22:19 EPO — how heat training naturally upregulates it
24:51 Are older athletes more vulnerable to heat stress
26:29 How to measure core temperature safely
44:39 Passive protocols — saunas and hot baths5
2:42 Active heat training — intensity and pacing
54:42 The ideal heat training block for a goal race
59:01 How long do the adaptations last
1:00:47 Maintenance dose to keep adaptations
1:01:19 The one thing any runner can do at home
1:02:31 When heat training is not worth it

Patrick Wilson is an exercise physiologist, sports nutrition researcher, and author of The Athlete's Gut. He has spent his career studying how the gut responds to food, fluid, and supplements during exercise — and what actually works versus what the industry wants you to believe.

In this episode Patrick breaks down the optimal carbohydrate intake per hour based on the actual dose response research, why going above 90 grams may not give you what you think it does, how gut training works and how quickly you can adapt, the truth about sodium bicarbonate and how to use it without destroying your race, what caffeine abstaining before a race actually does, and which supplements are genuinely worth your money and which ones are not.

The Athlete's Gut — https://www.amazon.com/Athletes-Gut-Digestion-Nutrition-Distress/dp/194800710X

0:00 The supplement industry0:57 Optimal carbs per hour9:21 The high carb and glycogen paradox11:40 Risks of high carb for recreational runners15:37 Risks of fasted and low carb training19:03 How to build a fuelling strategy without lab access24:12 Gel osmolality 26:57 Gut training 31:29 How quickly can gut training happen36:12 Heat and its effect on carb tolerance38:15 Sodium bicarbonate 43:59 How to use bicarb without the GI disaster54:49 Caffeine — sublingual vs oral delivery1:02:23 Should you stop caffeine before a race1:05:43 Acetaminophen as a performance aid1:09:28 Creatine for runners 1:11:54 Final takeaway on supplements and performance

#SportsNutrition #RunningSupplements #CarbsForRunners #EnduranceLab #GutTraining #SodiumBicarbonate #CaffeineAndRunning #MarathonNutrition #RunFaster #UltraRunningNutrition #EndurancePerformance #PatrickWilson #TheAthletesGut #RunningScience #MarathonTraining #FuelingForPerformance #RunnersNutrition #TrailRunningNutrition #UltraMarathon #ErgonicAids

Deena Kastor is a three-time Olympian, bronze medalist, former American marathon record holder, Chicago and London marathon champion, and US women's masters marathon record holder at 42 with a time of 2:27. She is one of the most decorated American distance runners of all time. But what made her great was not just her training. It was what she did with the six inches above her shoulders.
In this episode Deena breaks down exactly how she trained her mind to run faster, the daily practices that made her simultaneously happier and quicker, how she broke the masters marathon record despite wildfires, allergies, the flu, and a flawed race, why comparison does not have to steal your joy, and what runners over 40 need to hear about their relationship with the sport as times start to change.
This is a conversation about the science and practice of thinking your way to better running.

Resources:
1. Deena's Book: Let Your Mind Run - https://www.amazon.com/Let-Your-Mind-Run-Thinking/dp/1524760757
2. Deena's Website: https://www.deena-kastor.com/
3. Andrew Kastor's Coaching: https://www.coachkastor.com/

0:00 The mindset shift that changed everything
6:42 How to structure mental training
12:04 Does positive thinking actually make you faster
13:47 Mental approach as a masters athlete
15:48 Breaking the masters marathon record at 42
22:18 How to handle the pain cave in a race
26:20 Training now at 53
29:34 Recovery and how it has changed with age
31:05 How environment shapes running longevity
34:16 Advice for runners whose times are declining
36:29 Advice for runners still improving after 40
38:10 Navigating the decline from elite to masters
43:23 How to handle comparison
45:57 Training with only 5 to 6 hours a week
47:08 When injury takes running away
49:52 The book — Let Your Mind Run
57:54 How to work with Deena and Andrew
58:44 Final message to runners over 40

#DeenaKastor #MindsetForRunners #RunningMindset #RunnersOver40 #MastersRunning #MarathonMindset #EnduranceLab #LetYourMindRun #MarathonTraining #RunFasterAfter40 #MentalTraining #PositivePsychology #RunningMotivation #MastersMarathon #RunningOver40 #EliteRunning #MarathonPerformance #RunningLongevity #ThinkFaster #WomenRunning

Everyone seems to be chasing 120 grams of carbs per hour at the moment. But the research says that performance actually starts to dip after 100 grams per hour. And the fuelling plan behind two UTMB wins proves it.
Paul Booth is a sports nutritionist, exercise physiologist, and lead nutritionist for the Salomon International Team with 26 years in university academia and 92 ultras completed himself. In 2025 he built the customised fuelling strategies that won both the men's and women's UTMB 100. But what makes this conversation valuable is not what Tom Evans and Ruth Croft did. It is what you can take from it and apply to your next race.
In this episode Paul breaks down exactly how much carbohydrate you actually need per hour based on your intensity and fitness level, why going above 100 grams per hour may actually hurt your performance, how to train your gut so it does not fail you on race day, the glucose to fructose ratio that the research actually supports, and the one fuelling hierarchy mistake most ultra runners are making right now.
Whether you are racing a marathon, a 100k or a 100 miler this is the most practical fuelling conversation you will find.
Paul Booth:
Website: https://performancegainsnutrition.com/
Instagram: @ultra.endurance.nutritionist

Show notes links:
1. Ricardo Costa — Gut Training Research (the key paper Paul references)https://cdnsciencepub.com/doi/abs/10.1139/apnm-2016-0453
2. Ricardo Costa — Gut Training Systematic Review (most comprehensive overview)https://pubmed.ncbi.nlm.nih.gov/37061651/
3. O'Brien and Rowlands — The 0.8 fructose to glucose ratio paper (2011)https://journals.physiology.org/doi/full/10.1152/ajpgi.00419.2010
4. O'Brien and Rowlands — Fructose Maltodextrin Ratio Governs Performance (2013)https://www.researchgate.net/publication/255958218_Fructose-Maltodextrin_Ratio_Governs_Exogenous_and_Other_CHO_Oxidation_and_Performance
5. Alan McCubbin — Sodium ingestion and endurance performance systematic reviewhttps://research.monash.edu/en/publications/impact-of-sodium-ingestion-during-exercise-on-endurance-performan/

0:00 Why 120g/hr has no research behind it
1:11 The UTMB fuelling strategy explained
4:20 What lab testing actually reveals
13:06 How to deliver carbs during a race
16:35 Carb strategy for recreational runners
21:35 Do elites need more carbs than amateurs
28:36 Fuelling the second half of your race
33:30 Gut training and osmolality
38:18 Glucose to fructose ratios
43:05 More carbs does not mean better performance
50:47 Feeding frequency and electrolytes
57:54 The fuelling hierarchy
1:01:13 Final takeaway for your next race
1:03:46 What endurance means to Paul Booth