Running11 min
Galloway Method: The Complete Run/Walk Guide
Learn Jeff Galloway’s run/walk method: ratios by pace, training plans from 5K to marathon, and how strategic walk breaks prevent injury.
Read articleTraining Guides
Training tips, scientific guides, and expert advice for endurance athletes.
Science12 min
Muscle Fiber Types: Type I, IIa, and IIx Explained
Type I, IIa, and IIx muscle fibers each serve a different purpose. Learn what sets them apart, how to identify your dominant type, and what it means for your endurance training.
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Cycling14 min
Cycling Cadence: The 90 RPM Myth Debunked
Lower cadences are more efficient, yet elite cyclists pedal at 95+ RPM. Here’s what science says about finding your true optimal cadence.
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Health14 min
Signs of Overtraining: Symptoms, Recovery, Prevention
The 12 signs of overtraining, how long recovery really takes, and how to prevent it with training load and HRV monitoring.
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Health12 min
Training Around Your Menstrual Cycle
How the 4 menstrual cycle phases affect endurance, and how to time hard sessions, recovery and fueling for running, cycling and swimming.
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Nutrition12 min
Fasted Cardio and Fat Oxidation: Should You Train Fasted?
Fasted cardio and fat oxidation explained. Does training on an empty stomach burn more fat? The Fatmax truth, Zone 2, and who should skip it.
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Guide11 min
Sauna and Hot Bath for Endurance: Does It Work?
Can a post-workout sauna or 40°C hot bath boost VO2max? A 2025 study says yes. The protocol, the science, and how long the gains last.
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Guide14 min
Heat Training: How to Get Faster in Hot Weather
Heat training and heat acclimatization explained: a science-backed 10-day protocol, sport-by-sport tips, sauna and hot bath hacks, and safety thresholds.
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Running12 min
Running in Heat: Pace, Safety and Cooling Tips
Running in heat? Learn how much to slow down, when to run by effort, and how to cool down safely, with real pace-adjustment science.
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Science11 min
The 3 Energy Systems: How Your Body Fuels Exercise
How your body makes energy for sport: the ATP-PC, anaerobic and aerobic systems explained, and how to train each one.
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Cycling11 min
Watts per Kg: What Is a Good Power to Weight Ratio?
What is a good power to weight ratio in cycling? Calculate your watts per kg and see where you rank on the Coggan W/kg chart by level and gender.
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Running15 min
How to Prepare for Your First Marathon
How long to train, weekly mileage, the long run, race pace and tapering, built on the Jack Daniels method. A complete first marathon roadmap.
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Swimming11 min
What Is SWOLF? How to Improve Swim Efficiency
What is SWOLF, what is a good score, and how to improve it with better front crawl technique. Read your Garmin and Apple Watch SWOLF right.
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Science11 min
The 80/20 Rule: Why 80% of Training Should Be Easy
Why 80% of training should be easy and 20% hard, how to calculate your split, and how to dodge the moderate-intensity trap.
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Cycling11 min
Indoor vs Outdoor Cycling: Is the Trainer as Good?
Is indoor cycling as good as outdoor? Why you lose power on the trainer, the real benefits, the best weekly split, and which smart trainer to buy.
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Science9 min
Cardiac Drift: Why Your Heart Rate Rises Mid-Run
Cardiac drift makes your heart rate climb 10 to 20 bpm on a steady run. Learn why, and how to measure aerobic decoupling to check your fitness.
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Triathlon13 min
Brick Workouts: Master the Bike to Run in Triathlon
A brick workout chains a bike ride straight into a run. Learn why bricks matter, how to do them, and sample sessions by race distance.
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Science11 min
Running Economy: What It Is and How to Improve It
Running economy is how much oxygen you burn at a given pace. Learn what it is, how it's measured, and 6 proven ways to improve it.
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Science12 min
Lactate Threshold Explained: LT1, LT2 and Your Zones
Lactate threshold explained simply. Learn what LT1 and LT2 are, how to find your thresholds, and how to train each one to run and ride faster.
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Swimming11 min
Open Water Swimming: Technique, Sighting and Wetsuits
Open water swimming made simple. Learn sighting to swim straight, breathing, when to wear a wetsuit, and how to start safely.
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Triathlon12 min read
Which Triathlon Distance Should You Choose?
Sprint, Olympic, 70.3 or Ironman? Compare all 5 official triathlon distances side-by-side and pick the right one for your fitness, time and goals.
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Health12 min read
VO2 Max and Longevity: The Best Predictor of Lifespan
A landmark study of 122,007 patients found that elite fitness reduces all-cause mortality by 80%. Learn how VO2 max predicts lifespan and how to improve yours.
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Guide14 min
RPE Scale: The Complete Guide to Rating Perceived Exertion
Learn the RPE scale (Borg 6-20 and modified 1-10) to regulate training intensity. Interactive chart with HR zones and running guide.
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Cycling12 min
Training With a Power Meter: Complete Beginner Guide 2026
Learn how to use a cycling power meter: FTP testing, 7 power zones, key metrics (NP, IF, TSS), and how to structure training. Free zone calculator.
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Triathlon15 min
Beginner Triathlon Training Plan: 12 Week Sprint Guide
Complete guide to your first sprint triathlon. 12 week training plan, gear list, open water tips, transitions, pacing strategy, and race day timeline.
Read article![When Do Athletes Peak? Age & Performance Data [2026]](/_next/image?url=%2Fblog%2Fpeak-performance-age.jpg&w=3840&q=75)
Science12 min
When Do Athletes Peak? Age & Performance Data [2026]
Science-backed data on peak athletic performance age by sport. Marathon runners peak at 29–33, masters athletes thrive into their 40s. Check your endurance performance curve with our Max HR calculator and Race Predictor.
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Science12 min
VO2max Explained: Your Complete Guide
What is VO2max (Maximal Oxygen Uptake)? Understand your maximal oxygen consumption, find your level by age and gender, and discover the best workouts to improve.
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Nutrition12 min
Hydration and Electrolytes: Complete Guide
How much water and sodium do you need? Sweat rate testing, hyponatremia prevention, and hydration strategy for endurance athletes.
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Guide18 min
The Norwegian Method: Double Threshold Training Guide
Master the Norwegian Method of double threshold training. Workouts, 4x4 protocol, plans for runners and triathletes.
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Swimming12 min
Swim Pace Calculator: Critical Swim Speed Guide
Calculate your swim pace with our free CSS calculator. Test protocol, 5 training zones, Garmin comparison, race predictions. No lab needed.
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Health12 min
Heart Rate Variability Chart by Age: Normal Values
Interactive HRV chart by age and sex based on 84,772 participants. Find your percentile, understand normal RMSSD values, and track your recovery.
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Nutrition14 min
Carbs Per Hour for Endurance Athletes: Complete Guide
How many carbs per hour for cycling, running, triathlon? Science-backed guide with energy gel comparison and personalized race nutrition plans.
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Health12 min
Autonomic Nervous System for Athletes: Vagus Nerve Guide
Learn how the vagus nerve and autonomic nervous system control training and recovery. HRV, vagal tone, overtraining signs for athletes.
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Triathlon15 min
Triathlon Training Plan: Season Guide
Build your triathlon training plan with our complete periodization guide. Plans for Sprint, Olympic, Half and Ironman distances. Free framework included.
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Science12 min
Threshold vs Polarized vs Pyramidal Training
Compare polarized, threshold and pyramidal training models. Learn which intensity distribution works best for your sport and level. Science-backed guide.
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Guide10 min
Zone 2 Training: Complete Guide to Building Your Aerobic Base
Learn how to train in Zone 2 the right way. Includes heart rate calculator, 8-week plan, sport-specific tips for running, cycling and swimming.
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Cycling14 min
FTP Test at Home: 4 Protocols to Calculate Your Cycling FTP
Calculate your FTP at home with 4 proven protocols: 20-minute test, ramp test, 2×8-minute test. Free FTP calculator and power zones included.
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Science10 min
Tanaka Formula: Why 220 Minus Age Is Wrong
The 220 minus age formula can be off by 20+ bpm. Learn why the Tanaka formula (208 - 0.7 × age) is more accurate, backed by research on 18,712 subjects.
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Running15 min
Running Plan for Beginners: From Zero to 5K in 12 Weeks
Free beginner running plan with walk-run method: 8-week schedule, heart rate zones, gear guide, injury prevention. Download your printable plan.
Read articlePut theory into practice
Use our free calculators to find your personal training zones for heart rate, pace, power, and more.