The Athlete's Compass

In this episode of The Athletes Compass, Dr. Rebecca Robinson breaks down one of the most overlooked areas in endurance sports: women’s health across the lifespan, with a focus on perimenopause and menopause. Drawing from her experience as both a sports medicine physician and competitive marathoner, she explains how hormonal changes impact performance, recovery, and overall health—and why decline is not inevitable. The conversation covers fertility myths, training adaptations, nutrition strategies, strength training, and the importance of listening to your body. Ultimately, this episode reframes aging as an opportunity to evolve your training, not limit it.Key TakeawaysPerformance decline is not fixed—many women are peaking into their 40s and beyond.Overtraining and low energy availability can temporarily affect fertility, but long-term damage is unlikely.Estrogen plays a major role in bone health, cardiovascular protection, and recovery.Strength training becomes essential for maintaining muscle, bone density, and balance.Recovery, sleep, and fueling (especially carbs + protein) are more important than ever.Fasted training may increase stress and is generally not recommended for women.Hormone Replacement Therapy (HRT) should be individualized—not a blanket solution.Symptoms like fatigue, brain fog, and poor sleep can mimic overtraining.Listening to your body is the most powerful coaching and training tool.Enjoyment and community are critical for long-term athletic success.Dr. Rebecca RobinsonPaul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

In this episode, Erin Carson, one of the most respected strength coaches in endurance sports, breaks down why movement quality is the foundation of performance, injury prevention, and long-term athletic success. She explains how many athletes are already “strong enough” but are limited by stiffness, poor mechanics, and inefficient movement patterns. From simple at-home routines to the concept of “easy speed,” Erin shares practical strategies to improve mobility, unlock better performance, and train for longevity, so you’re not just faster today, but still moving well decades from now.Key TakeawaysMovement quality = efficiency. Better movement reduces energy cost and improves performance quickly.Many athletes don’t need more strength—they need better mobility and coordination.“Easy speed” comes from improved mechanics, not just fitness gains.Tightness in the front of the body inhibits strength in the back (reciprocal inhibition).Most endurance athletes are overly tight in hip flexors and chest due to training posture.Overhead squats are a powerful diagnostic tool for mobility limitations.Ankles, hips, and thoracic spine are the three key mobility areas.Strength training should support movement, not compromise it.Small, consistent routines (“four things”) are more effective than complex programs.Multi-directional movement reduces injury risk and improves durability.Elastic energy (bounce) is more efficient than muscular force.Variety in training (especially for youth athletes) is critical for long-term success.Longevity training starts now: how you move today determines how you age.Use the Code: COMPASS to get a discounted membership for $19.99 per month.ECFIT - 2 Week TrialPaul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

This episode explores one of the most debated topics in endurance training: whether athletes should take full rest days or train every day. Drawing from elite athlete examples and recent research, the hosts explain that there’s no single “correct” approach. Instead, recovery depends on training intensity, individual preferences, and lifestyle. They highlight the importance of low-intensity (zone 1) training, the role of the nervous system in recovery, and why many athletes sabotage progress by pushing too hard on easy days. Ultimately, recovery—whether active or complete—is a critical part of performance, not a break from it.Key TakeawaysThere is no universal rule: both daily training and scheduled rest days can work.Elite athletes follow vastly different recovery strategies—context matters.Active recovery (zone 1 movement) can enhance recovery through parasympathetic activation.Many athletes train “easy days” too hard, limiting adaptation.Zone 1 and Zone 2 training are crucial for building aerobic capacity and heart function.Full rest days are especially valuable when fatigued, sick, or mentally drained.Recovery is not just physical—it’s also mental and emotional.Walking, mobility work, and light movement are highly underrated recovery tools.Low-volume athletes may not need full rest days but should manage intensity carefully.Consistency and quality of sessions matter more than rigid schedules.Ep. 34 Øyvind Sandbakk: The Sc… - Race Ready - Apple PodcastsPaul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

Heart rate variability (HRV) is transforming how endurance athletes approach training by providing real-time insight into recovery and readiness. Instead of following rigid training plans, HRV allows athletes to adapt workouts based on their nervous system state, leading to better performance gains and reduced risk of overtraining. This episode breaks down what HRV actually measures, how it reflects the balance between stress and recovery, and why factors like sleep, stress, and lifestyle play a major role. The discussion also explores practical strategies to improve HRV, when to adjust training intensity, and how to interpret low HRV without overreacting.Key TakeawaysHRV measures the variation between heartbeats and reflects nervous system balanceHigher HRV generally indicates better recovery and readiness to trainHRV-guided training leads to better performance gains than static plansPoor sleep is one of the biggest drivers of low HRVOne low HRV day → switch to aerobic trainingTwo consecutive low HRV days → consider full restChronic low HRV requires looking at the bigger picture (stress, hormones, lifestyle)Aerobic training is the most effective way to improve HRVStrength training is beneficial but should avoid training to exhaustionConsistency and context matter more than single HRV readingsWhy Your HRV Won’t Improve — Daily Reset to Boost RecoveryPaul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

In this episode of the Athletes Compass Podcast, the hosts explore the pros and cons of training alone versus training in a group. Recent research suggests that while both approaches can produce similar fitness outcomes, group training may lead to greater improvements in functional performance due to social support and motivation. The discussion highlights psychological drivers like self-efficacy, autonomy, and relatedness, and how they shape training success. The hosts share personal experiences with solo workouts, group sessions, and online communities, ultimately concluding that the optimal approach is often a balance tailored to an athlete’s personality, schedule, and goals.Key Episode TakeawaysBoth solo and group training work – overall fitness improvements can be similar across both approaches.Group training may enhance functional performance such as strength and flexibility due to social motivation.Psychological factors matter – social support boosts self-efficacy and self-regulation, which can improve performance.Autonomy vs relatedness – solo training supports independence, while group sessions provide connection and accountability.Training context matters – competitive athletes may benefit from focused solo sessions, while others thrive in social environments.Groups can push athletes beyond perceived limits, helping them discover untapped strength.Races often require solo resilience, making some independent training essential.A balanced approach (often around 80% solo / 20% group) can combine efficiency with motivation and social benefits.Paul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

In this episode of the Athletes Compass Podcast, the hosts explore Athletica’s new AI Coach, a tool designed to provide personalized training feedback and answer athlete questions based on the science of high-intensity interval training. Built using a retrieval-augmented AI system trained on the HIIT Science textbook and Athletica’s internal knowledge base, the coach analyzes workout data, recovery metrics, and athlete comments to generate contextual advice. The conversation highlights real-world examples of how athletes use the tool to improve pacing strategies, adjust training plans, monitor recovery, and avoid injury. The hosts also discuss how consistent logging of RPE and workout notes strengthens the system over time and share a vision for the future where AI could automatically adjust training plans in real time.Key Episode TakeawaysAthletica’s AI Coach is powered by RAG AI (Retrieval-Augmented Generation), pulling from the HIIT Science textbook, blogs, and platform knowledge to answer training questions.The system combines scientific knowledge with an athlete’s personal data including power profiles, training load, and recovery metrics.Athletes can ask questions about: recovery status, training intensity distribution, pacing strategies, nutrition for key workouts, strengths and weaknesses in their data.The AI can reference historical training data, even comments written months earlier, to give contextual advice. Example use cases include: deciding workout order (threshold vs endurance), planning pacing strategies for races, adjusting training after illness or injury.Consistency in training and logging feedback (RPE, notes, comments) improves the AI’s ability to give useful recommendations.The current system cannot automatically modify your training calendar, but future versions may include that capability.A strong aerobic base remains essential—relying only on high-intensity sessions can lead to plateaued fitness and reduced recovery capacity.Athletica's Architecture Paul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

Episode SummaryIn this episode of The Athletes Compass, the team sits down with Siren Seiler-Viken—researcher, coach, and emerging voice in Hyrox performance science. From her early years as an elite dancer to national-level distance running and now competitive Hyrox racing, Siren shares how sustainability, intelligent planning, and aerobic development form the foundation of hybrid performance. The conversation explores the physiological demands of Hyrox, why running may be the most overlooked performance driver, how to balance strength and endurance without sabotaging adaptation, and why pacing strategy can make or break your race. Whether you're a competitive athlete or new to hybrid fitness, this episode delivers practical, science-backed insight on building performance that lasts.Key Episode TakeawaysRunning accounts for ~60% (or more) of Hyrox race time — aerobic development is foundational.Wall balls produce the highest physiological strain due to total-body demand + accumulated fatigue.Hyrox is primarily an endurance event with strength elements—not the other way around.Max strength matters—but mostly to raise your ceiling so race loads feel submaximal.Muscle mass can become a liability if it compromises running economy.A pyramidal or polarized endurance approach builds sustainable fitness.Double-threshold training can be effective for advanced athletes when carefully structured.Splitting strength and endurance sessions by 5–6 hours reduces interference effects.Pacing is critical—early overexertion can derail the entire race.Variation in endurance modalities (run, row, ski) supports durability and injury prevention.Hyrox’s appeal lies in accessibility, inclusivity, and standardized global competition.Timestamps:00:00 – Injury Prevention & Mixing Modalities02:07 – From Elite Dance to National-Level Running07:57 – What Is Hyrox? Format & Demands12:03 – Why Running Determines Hyrox Performance16:25 – Why Wall Balls Break Athletes22:13 – Is Max Strength Overrated in Hyrox?26:25 – Programming: Base Building, Strength & Specificity52:35 – Double Threshold & Concurrent Training46:05 – The Rise of Hyrox & Olympic PotentialSiren Seiler-Viken CoachingPaul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

In this powerful and deeply relatable episode, Jeff Weiss shares how he went from starting his first 10K at age 48 to completing Ironmans, ultra marathons, and chasing the World Marathon Majors in his 60s. Along the way, he unpacks the mental battles behind endurance sport, the value of failure, and why chasing big goals reshapes how we see ourselves. From narrowly missing the cutoff at the legendary Comrades Marathon to discovering resilience through ice baths and yoga, Jeff makes a compelling case that racing isn’t just about fitness — it’s about identity, courage, and choosing a life without regret.Key Episode TakeawaysYou’re never too old to start — progress is possible at any age.Big races build identity and self-belief, not just fitness.Failure can unlock even bigger breakthroughs.Planning your “next goal” prevents post-race emotional crashes.Working with a coach builds confidence, accountability, and consistency.Long races reveal mental weaknesses — and mental strength.Ice baths and endurance racing both train the same muscle: courage.Controlled discomfort in sport builds resilience for life and business.“Do it scared” — fear is natural, but action reduces it.Health span (not just lifespan) should be the real goal of training.Paul Warloski - Simple Endurance CoachingMarjaana Rakai | Nordic Performance Lab

In this episode of The Athletes Compass, Dr. Paul Laursen and the team break down the science and practical application of the second threshold — also known as LT2, VT2, FTP, or critical power. They explain what physiologically happens when you cross this boundary, why base training is essential before adding threshold work, and how over-unders, tempo sessions, and VO2 max intervals raise performance. The conversation explores common mistakes athletes make (especially doing too much intensity), the role of durability, and how to assess threshold progress without lab testing. If you want to train smarter, improve pacing, and sustainably increase performance, this episode delivers a masterclass in intensity control.Key TakeawaysLT1 vs LT2: LT1 (aerobic threshold) = top of Zone 2, sustainable “all-day” effort. LT2 (second threshold) = highest sustainable steady-state effort before rapid fatigue.Above LT2: Glycolytic demand increases, lactate accumulates faster, heart rate drifts, and fatigue accelerates.Functional vs Lab Testing: FTP and critical power are practical field markers of LT2. Lab tests measure physiology, but field tests often matter more for performance.Day-to-Day Variation Is Real: Sleep, fueling, equipment, environment, and training phase can significantly affect test results.Base Training First: A strong aerobic base (mitochondrial development) improves tolerance to threshold work and increases fat oxidation capacity.Over-Unders Work Because: They stimulate mitochondrial adaptations by forcing lactate clearance and improving aerobic durability.Intensity Control Matters: Spending more time in the correct zone is more beneficial than constantly pushing the top end.Most Common Mistake: Too much high-intensity work without sufficient aerobic base.Durability Is the Goal: Threshold training should build resilience so performance doesn’t break down late in races.Paul Warloski - Simple Endurance CoachingMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In this episode, Dr. Mikki Williden returns to The Athletes Compass to explore the Constrained Energy Model, a concept reshaping how athletes and coaches think about training and fueling. Drawing on the groundbreaking work of Dr. Herman Pontzer, Mikki discusses the biological limits of daily energy expenditure, and why the old model of "more exercise = more calories burned" often backfires, leading to fatigue, weight gain, and hormonal dysfunction. The conversation tackles RED-S, perimenopause, nutrient timing, energy availability, and the limits of tracking tools, all while emphasizing the importance of individual context, intuitive feedback, and informed nutrition.Key Episode TakeawaysThe Constrained Energy Model posits that daily energy expenditure plateaus, even with increased exercise.Energy is redirected from "non-essential" functions like immunity and reproductive health under high training loads.Over-relying on devices or formulas to track calories burned can lead to overfueling, weight gain, or gut issues.RED-S (Relative Energy Deficiency in Sport) can impair hormones, recovery, and bone health, especially in female athletes.Basal metabolic rate (BMR) forms the majority of energy use, but varies with sex, age, lean mass, and training history.Fueling needs are individual: what works for Michael Phelps or Killian Jornet won’t work for everyone.Tools like calorie counters can be helpful for education, but not as rigid frameworks.Protein and strength training are critical, especially for perimenopausal women looking to protect bone and muscle mass.Paul Warloski - Simple Endurance CoachingMikkipedia | Dr. Mikki Williden’s podcast, covering topics such as nutrition, fitness, and longevity.Marjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In this episode of Athlete’s Compass, hosts Paul Warloski, Dr. Paul Laursen, and Marjaana Rakai explore the overlooked yet critical elements of pre-race preparation: warmups and openers. Drawing on science and experience, they break down concepts like post-activation potentiation (PAP), the Q10 temperature effect, VO2 kinetics, and how proper timing, intensity, and individual context can make or break race performance. The trio shares personal anecdotes, training data insights, and cautionary tales (including cold-water swims gone wrong), helping athletes navigate both physiological and psychological readiness strategies. Whether you’re a crit racer, triathlete, or weekend warrior, this episode will change the way you approach race day — and the day before.Key TakeawaysPost-Activation Potentiation (PAP) boosts nervous system readiness for explosive performance.Q10 effect (temperature-driven) enhances muscle enzyme activity—warm muscles perform better.VO2 kinetics are improved with short, intense primers done 5–10 minutes before start time.Day-before openers should include high-intensity, low-volume efforts to keep CNS sharp without fatigue.Warmup routines are highly individual—test in training, adjust for temperature and race type.Over-warming or overtraining pre-race is a common mistake; less is more.Cold environments demand longer warmups and appropriate clothing to avoid CNS suppression.Caffeine can enhance CNS drive when timed 30–90 minutes before competition—test before race day.Paul Warloski - Simple Endurance CoachingEffect Of High Intensity Intervals 24hr Prior To A Simulated 40 KM Time TrialThe Effects of a Cycling Warm-up Including High-Intensity Heavy-Resistance Conditioning Contractions on Subsequent 4-km Time Trial Performance - PubMedEffect of warm-up on cycle time trial performance - PubMedImprovement of Oxygen-Uptake Kinetics and Cycling Performance With Combined Prior Exercise and Fast Start - PubMedMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In this episode, triathlete Jerome Guionnet shares his inspiring transformation from a non-competitive French parent to a world-class age-group triathlete competing in multiple Ironman World Championships. Sparked by his daughter’s interest in triathlon, Jerome began his journey in his 50s and now regularly finishes in the top 10% of his age group. He discusses the difference between exercising and structured training, the value of consistency, recovery, coaching, and cutting-edge tech like AI coaching and biometric wearables. Jerome also opens up about time management, the importance of strength training, and the surprising mental tricks that keep him going, even in low-motivation moments.Key Episode TakeawaysStarting triathlon later in life is possible with structured training and motivation.Exercising is not the same as training—purposeful structure yields results.AI tools like Athletica help with personalized insights, but coaches bring human touch and emotional intelligence.Consistency, especially with zone 2 training, is essential but often lonely.Time management includes using “bricks” (back-to-back workouts) and home trainers for efficiency.Strength training and activation exercises help prevent injury and improve running form.Transition time is a weakness Jerome plans to improve by doing more local races.Gadgets like Timeware and Cori (continuous lactate monitoring) are part of Jerome’s optimization toolkit.Training is part of a balanced lifestyle that improves work performance and mental health.Paul Warloski - Simple Endurance CoachingMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In this episode, the Athletes Compass team dives into the physiology and performance science behind 30/30 HIIT intervals—30 seconds on, 30 seconds off. Dr. Paul Laursen explains why these short, intense bursts are so effective at improving VO2 max and recruiting fast-twitch muscle fibers. With insights into training stress, recovery, athlete profiling, and when to use short versus long intervals, the conversation highlights how even endurance athletes can benefit from raising their "ceiling" with strategically timed HIIT sessions. They also cover programming for different athlete types and how tools like Athletica and Velocity help customize training to individual needs.Key Takeaways:30/30 intervals (30 seconds on, 30 seconds off) effectively recruit fast-twitch fibers and promote adaptations in both the cardiovascular and muscular systems.These short intervals stimulate VO2 max while minimizing long-term fatigue compared to longer intervals.Power output is higher during 30/30s than in 4x5 minute VO2 workouts, leading to better adaptations in well-trained athletes.Recovery periods between intervals are key—passive recovery enables myoglobin resaturation and better performance.30/30s can benefit even Ironman athletes, despite the lack of specificity to long race paces.Athlete type matters: “Diesel” athletes may prefer longer intervals; “twitchy” athletes often thrive with short ones.Tools like Athletica’s workout reserve and power profile analysis help guide interval prescription.Heart rate and power trends during sets can indicate whether an athlete is adapting well—or overreaching.Paul Warloski - Simple Endurance CoachingAthlete Profiling PrimerThe Power of Optimizing HIIT Short IntervalsMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In Episode 110, the hosts of The Athletes Compass dive into the overlooked powerhouse of endurance training: cross-training. Dr. Paul Laursen, Marjaana Rakai, and Paul Warloski explore how activities like rowing, skiing, and cycling aren't just recovery fillers—they're performance-enhancing tools backed by science. The trio debates whether strength training should count as cross-training, unpacks when specificity should take priority, and shares stories of elite athletes like Kyle Chalmers and Mahe Drysdale whose success came from training smarter, not harder. More than anything, the conversation is a powerful reminder that enjoying your training—and staying injury-free—may be the ultimate performance advantage.Key TakeawaysStrength Training ≠ Cross-Training: It’s foundational and should be part of every endurance athlete’s program.Specificity Still Matters: But the need for it increases closer to race day.Cross-Training Works: It can directly improve aerobic fitness, reduce injury risk, and maintain performance.Minimum Effective Dose Exists: You might not need as much sport-specific work as you think.Joy Enhances Adaptation: Enjoyable training (including cross-training) supports better recovery and long-term consistency.Elite Athletes Use It: Olympic champions like Mahe Drysdale and Nils van der Poel used 50%+ cross-training in their routines.Technique is Sport-Specific: For technical sports like swimming or skiing, keeping some year-round specificity is key.Balance is Critical: Cross-training supports mental freshness and helps athletes avoid burnout.

In this episode of The Athlete’s Compass, the team introduces Athletica’s newly launched AI coach—an intelligent training assistant that combines large language models (LLMs) with athlete-specific data like HRV, sleep, and training load. Unlike generic AI tools, this coach taps into the HIIT Science textbook and contextualizes advice based on six weeks of an athlete’s training history. Paul Laursen, Marjaana Rakai, and Paul Warloski walk through how it works, what sets it apart, and demonstrate its capabilities in real-time. The conversation highlights not only the tech’s sophistication but its potential to empower athletes and coaches alike through contextual, science-backed decision-making.Key TakeawaysAI + Personal Data = Precision Coaching: The AI coach analyzes training data like HRV, heart rate, and sleep to give context-aware, real-time advice.HIIT Science Textbook is Embedded: It doesn’t guess—its responses are backed by content from The Science and Application of High-Intensity Interval Training.Real-Time Scenarios: Whether you're sick, tapering, or targeting a hilly Ironman, the AI provides personalized strategies.Built-In Guardrails: It won’t override your training plan but will suggest appropriate tweaks based on your context.For Coaches Too: While not yet multi-athlete enabled, future updates will allow coaches to use it across their roster.Customization: Users can adjust the coach’s personality (casual/professional) and depth (plain language to sports science level).AI Agent Architecture: It uses Retrieval-Augmented Generation and purpose-built agents (e.g., for recovery or training load optimization).More Than a Chatbot: Unlike ChatGPT, this coach knows your actual training history and adjusts accordingly.Paul Warloski - Simple Endurance CoachingMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.

In this episode of the Athletes Compass Podcast, Mollie Brewer—sports scientist and PhD researcher—explores the fine line between using training technology as a helpful tool and becoming overly dependent on it. Drawing from research across collegiate and endurance sports, Mollie explains how GPS watches, power meters, HRV, and AI platforms can either reduce cognitive burden or create “techno stress” when athletes chase numbers instead of listening to their bodies. The conversation highlights data literacy, pacing mastery, individualized training, and why the best outcomes come from triangulating data, bodily awareness, and life context rather than letting metrics dictate every decision.Key Episode TakeawaysTraining technology works best when it supports decision-making, not replaces itChasing metrics can increase anxiety, reduce enjoyment, and harm performanceData can both “get athletes out of their head” and “get athletes into their head”Over-testing and constant measurement can reduce data quality and athlete engagementAthletes need data literacy to understand trends, noise, and contextEffective training comes from triangulating data, bodily feel, and life demandsAI and wearables should adapt to the athlete—not force the athlete to adapt to themSocial sharing of data (e.g., Strava) can amplify techno stressPaul Warloski - Simple Endurance CoachingMarjaana Rakai - Tired Mom Runs - Where fitness meets motherhood.