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PIRX Guides

Race prediction, pacing & training guides

Evidence-led guides that turn one race result into a plan — and a projected time you can trust.

Showing 101 of 101 guides

Lone runner on an open road stretching toward the horizon at golden hour.Start here

Pillar guide · Start here

How to Predict Your Race Time (No Watch Needed)

Predict race time at any distance from one race you already ran. No watch, no signup. How prediction works and how accurate it is.

Updated May 20265 min read

Runner on a long open road that stretches toward the horizon.Predict

What Marathon Can I Run Off My Half Marathon Time?

Find the marathon time you can run from your half marathon. Learn why a marathon is more than double your half, and how to set a smart goal.

Updated May 20264 min read

Runner holding a strong, steady pace on an open road.Predict

5K to 10K Time Conversion: What 10K Can You Run?

Convert your 5K time to a realistic 10K. See how much slower 10K pace is than 5K pace, what it takes to hold it, and predict your 10K free — no watch, no signup.

Updated May 20264 min read

Half marathon runner holding a strong steady pace on a city road.Predict

10K to Half Marathon: What Half Can You Run?

Predict your half marathon from a recent 10K. See half pace vs 10K, long runs needed, and project your half free. No watch, no signup.

Updated May 20264 min read

Runner striding along an open road that stretches toward the horizon.Predict

Race Equivalency Explained: Your Times at Every Distance

Race equivalency times from a 20:00 5K to a 3:11 marathon. See the ladder, why one race maps to all distances, and where math breaks. Free, no signup.

Updated May 20264 min read

Runner standing focused at the edge of an open road, looking toward the horizon.Predict

Is My Goal Time Realistic? An Honest Test

Is your marathon goal realistic? Compare your goal to projected time, see a fair jump for one block, and spot fantasy goals. Free, no signup.

Updated May 20264 min read

Runner relaxed and at ease on an easy conversational run down a tree-lined path.Train

Training Paces Explained: The 5 Speeds Every Runner Needs

Training paces explained: easy, marathon, threshold, interval, and speed from one recent race, and what each builds. Free, no signup, no watch.

Updated May 20264 min read

Runner on a long easy run along a scenic open road in soft morning light.Train

What Pace Should My Long Run Be? (By Goal Marathon)

Find long run pace by goal marathon time. Easy pace for most miles, marathon-pace segments later, and why most runners go too fast. Free, no signup.

Updated May 20264 min read

Marathon runner holding a steady, even pace along a city marathon street.Train

Marathon Pace Chart: Splits for Every Finish Time

Marathon pace chart with per-km and per-mile splits from 2:45 to 5:00. Use it on race day and learn why even splits win. Free predictor, no signup.

Updated May 20263 min read

Runner on a long training run along a rolling rural road at golden hour.Train

How Many Weeks to Train for a Marathon?

How many weeks to train for a marathon? Timelines for beginner, intermediate, and advanced runners plus safe mileage rules. Free, no signup.

Updated May 20264 min read

Runner holding a steady marathon pace along a long open city road.Race day

How to Pace a Marathon: Even, Negative, and the First-10K Trap

How to pace a marathon without fading: even vs negative splits, the first-10K trap, and how to lock target pace. Free finish predictor, no signup.

Updated May 20264 min read

Tired marathon runner slowing and grimacing in the late miles of a city race.Race day

Why You Faded in the Last 10K (and How to Fix It)

Slowed down in the last 10K of your marathon? Four common causes: too fast start, underfueling, low volume, poor durability. Fix yours free, no signup.

Updated May 20264 min read

Runner on a sidewalk checking a running app on a smartphone after a workout.Race day

Strava vs Garmin vs PIRX: Which Race Prediction Should You Trust?

Strava vs Garmin vs PIRX for race prediction: what each reads, where each drifts, and which explains your finish time. Free predictor, no signup.

Updated May 20263 min read

Runner looking puzzled at a race prediction on a GPS watch after a run.Predict

Why Your Smartwatch Thinks You're Faster (or Slower) Than You Actually Are

Are smartwatch race predictions accurate? Often no. Your watch guesses VO2 max, then misjudges endurance vs speed. See why it errs, plus a free fix, no signup.

Updated May 20268 min read

Runner looking skeptically at a race time estimate on a phone after a run.Predict

Are Race Time Calculators Accurate? Why Most Miss

Are race time calculators accurate? Often no. A single fixed formula treats every runner the same and overpredicts the marathon. See the free, no-signup fix.

Updated Jun 20269 min read

Tired runner bent with hands on knees on a road, frustrated after a flat effort.Train

5 Signs Your Training Plan Isn't Working

Hitting your mileage but not getting faster? Here are 5 signs your training plan isn't working, and the performance driver behind each. Free, no signup.

Updated Jun 20269 min read

Runner on a consistent early-morning training run through a quiet suburb.Predict

How Much Data Does a Race Predictor Need?

How much data does a race predictor need to be accurate? More than one run. See how training history sharpens your projection and Supported Range. Free, no signup.

Updated Jun 202610 min read

Marathon runner holding an efficient, economical stride on an open road.Predict

Is VO2 Max a Good Predictor of Marathon Time?

Is VO2 max a good predictor of marathon time? Not really. Two runners can share a VO2 max yet run very different marathons. See what matters more, free, no signup.

Updated Jun 20269 min read

Runner in a fast, committed 5K effort on a city road.Predict

Case Study: How Data, Not Guesswork, Cut 22 Seconds Off a 5K Pace

Learn how to drop 5k time with data. See how one illustrative runner's PIRX driver scores exposed the exact gaps behind a 22-second 5K gain. Free, no signup.

Updated Jun 20269 min read

Runner sitting and reviewing recent training on a phone after a session.Predict

The Science of Running Projections: Week One Round-Up

The science of running race prediction shows that generic guesses fail every runner. Recap the week's five key insights and sync your watch to see your real number.

Updated Jun 20269 min read

Runner in a focused, committed 10K effort on an open road.Train

Aerobic Base vs Speed Exposure: Which One Is Holding Back Your 10K?

Aerobic vs anaerobic for 10K: engine size vs top speed, which limiter costs seconds, and how to fix it. Free race predictor, no signup.

Updated Jun 20269 min read

Marathon runner deep in the late miles, fatigued but holding form on a city street.Train

Fatigue Resistance: How to Stay Strong When the Wall Hits at Mile 20

How to avoid hitting the wall at mile 20: build Aerobic Base and Load Consistency for late-race strength. Free race predictor, no signup.

Updated Jun 20269 min read

Runner with a smooth, efficient stride on an open road in warm late-day light.Train

Metabolic Fitness: How Fueling and Pacing Set Your Projected Finish Time

Metabolic fitness running performance hinges on Running Economy and Threshold Density. See how smart fueling and pacing convert both into your finish time.

Updated Jun 202610 min read

Runner cresting a hilltop road at sunrise with strong, confident form.Train

The 5 Drivers That Set Your Race Day Ceiling

What determines running performance? Five drivers set your race day ceiling, each scored 0 to 100. See where your seconds come from, free and no signup.

Updated Jun 20269 min read

Healthy, strong half-marathon runner holding a steady moderate effort on a road.Train

Why Peak Mileage Alone Will Not Save Your Half Marathon

Does more mileage make you faster at the half marathon? Not always. See the two drivers that predict your finish time better than peak weekly miles. Free, no signup.

Updated Jun 20269 min read

Runner pausing on a road to catch their breath, reflective and self-assessing.Train

How to Identify Your Running Leak Before Race Day

What is limiting my running performance? In most runners, one of the five performance drivers is the weak link. Find your leak, fix that driver, and run faster.

Updated Jun 20269 min read

Lone distance runner training at dawn as a rising Projected Time curve glows ahead on the track.Train

Stop Guessing What Your Workouts Are Worth: Week Two Summary

How to know if a workout helped: it must shift your Projected Time by at least 2 seconds. This Week 2 recap scores all 5 drivers so no run goes wasted.

Updated Jun 202610 min read

Determined runner pushing up a long steep hill road, breaking through effort.Train

Hitting the Same Personal Best Ceiling Every Season? The Math on Why

Wondering why have I stopped getting faster? Your body adapts to the same signal in weeks. Here is the math on breaking a running plateau. Free predictor.

Updated Jun 20269 min read

Runner in a purposeful, focused training session on an outdoor track.Train

Stop Wasting Mileage on the Wrong Workouts for Your Goal

Right workouts for my race goal depend on your target distance. 5K runners need Speed Exposure. Marathon runners need Aerobic Base. See the full breakdown, free.

Updated Jun 20268 min read

Confident runner standing composed at the start of an open road at dawn, looking ahead.Predict

How to Know What You Are Capable of Before the Race Starts

How to know my race potential before race day. Your Projected Time and Supported Range show exactly what your training supports. Free, no signup needed.

Updated Jun 20269 min read

Runner paused on a road, hand on a sore lower leg with a cautious expression.Train

Mid-Block Running Injuries: How Overloading One Driver Blurs Progress

Overtraining injury risk spikes when load grows faster than you adapt. See the early workload signal and how to grow all five drivers safely.

Updated Jun 20269 min read

Recovered, relaxed runner standing on a path in soft morning light before a session.Train

What Your Event Readiness Score Means for Your Next Hard Session

Your readiness score for running tells you which session to pick today. See PIRX's 4 Event Readiness bands and why it never changes your Projected Time.

Updated Jun 202610 min read

Runner working hard with heavy, tired legs deep in a demanding training block.Train

Why Hard Training Does Not Always Show Up on Race Day

Training hard but not racing faster? Buried fatigue hides your fitness. Learn why race output lags behind training and how to fix it. Free predictor, no signup.

Updated Jun 20268 min read

Runner pausing mid-run on a trail, looking back thoughtfully to take stock.Train

The Ultimate Mid-Block Training Assessment: Week Three Review

Mid training block check in: week three is the window to fix gaps before they cost you on race day. See the signals, the actions, and a free projection. No signup.

Updated Jun 20268 min read

Runner holding a smooth, even stride on an open road in daylight.Race day

The Math of Perfect Pacing: Negative Splits vs Even Splits

Negative splits vs even splits: learn which math wins and how to turn your Projected Time into mile-by-mile split targets. Free marathon predictor, no signup.

Updated Jun 20268 min read

Runner climbing a hilly road in bright sun on a hot, hazy day.Race day

How Heat, Hills, and Wind Change Your Race Time

Learn how to adjust race time for heat and hills. See how warm weather, headwind, and net climbing slow your pace and set a real target. Free, no signup.

Updated Jun 20269 min read

Runner with a powerful balanced stride on an open road.Predict

Why the Same Fitness Predicts Different Race Times Across Distances

Why does your race time across distances shift? Learn how energy systems change per event and how PIRX adjusts your 5 drivers per race. Free predictor, no signup.

Updated Jun 202610 min read

Runner on a relaxed shake-out jog through a green park during marathon taper.Race day

How to Taper for a Marathon Without Losing Fitness

How to taper for a marathon: cut volume 40-60%, keep intensity, and arrive fresh. Week-by-week plan backed by race data. Free predictor, no signup.

Updated Jun 20269 min read

Runner glancing at a GPS sports watch on the wrist after finishing a run.Predict

How to Predict Your Race Time With the Watch You Already Own

predict race time with my watch using Garmin, COROS, or Apple Watch. PIRX reads runs you already own and builds a real projection. Free, no signup.

Updated Jun 20268 min read

Runner breathing and staying calm in a crowded start corral before a race.Race day

The Psychology of Knowing Your Number on Race Day

Race day nerves hit hardest at the start line. A Projected Time, Supported Range, and split plan shift fear to confidence. Free predictor, no signup.

Updated Jun 20269 min read

Focused runner waiting at the start line on a cool race morning.Race day

The Complete Race Day Strategy Checklist

Use this race day strategy checklist to set pace, fuel, environment, taper, and mindset from real data. Five levers, one plan. Free predictor, no signup.

Updated Jun 20269 min read

Runner standing in an urban park after a run, reviewing training data on a phone.Predict

The Future of Running Analytics: Why Spreadsheets Are Done

Future of running analytics: from formulas and spreadsheets to machine learning race prediction. What changed and what comes next. Free, no signup.

Updated Jun 20268 min read

Runner crossing a race finish line with arms raised in triumph.Race day

How to Run Your Fastest Race: The Complete PIRX Method

Learn how to run your fastest race in 4 steps: connect, analyze, deconstruct your drivers, execute with a plan. Free predictor, no signup.

Updated Jun 20268 min read

Beginner runner holding a steady even effort on a park path during a 5K.Train

How to Run a Sub-30-Minute 5K

A sub 30 5k is about 5:59 per km. Get the exact pace, splits, and a simple beginner training plan, then check the goal fits your data. Free, no signup.

Updated Jun 20268 min read

Intermediate runner pushing a hard, controlled tempo effort on an outdoor track.Train

How to Run a Sub-25-Minute 5K

A sub 25 5k training plan starts at 5:00 per km. Get the exact pace, splits, and the speed and threshold workouts that move you there. Free, no signup.

Updated Jul 20269 min read

Competitive runner at near-maximal effort on a track chasing a sub-20 5K.Train

How to Run a Sub-20-Minute 5K

A sub 20 5k training plan means holding about 4:00 per km for 5 km. Get the exact pace, splits, and the speed work that breaks 20 minutes. Free, no signup.

Updated Jul 20268 min read

Runner holding an even, controlled effort on an open road during a 10K.Train

How to Run a Sub-50-Minute 10K

A sub 50 10k means holding about 5:00 per km for all 6.2 miles. Get the exact pace, checkpoint splits, and weekly mileage to train for it. Free, no signup.

Updated Jul 20269 min read

Fit runner holding a hard, controlled threshold pace on an open road.Train

How to Run a Sub-40-Minute 10K

A sub 40 10k training plan means holding about 4:00 per km for 6.2 miles. Get the pace, splits, threshold workouts, and weekly mileage to break 40. Free, no signup.

Updated Jul 20268 min read

Half marathon runner holding a steady, controlled pace on a long open road.Train

How to Run a Sub-2-Hour Half Marathon

A sub 2 hour half marathon needs a 5:41 per km pace, a long run past 21 km, and even splits. See the exact pace, plan, and honest check. Free, no signup.

Updated Jul 202610 min read

Lean competitive runner holding a fast, controlled threshold pace on the road.Train

How to Run a Sub-1:30 Half Marathon

Sub-90-minute half marathon training: the 4:16/km pace, exact splits, threshold work, and the mileage floor it really needs. Free, no signup, no watch.

Updated Jul 20269 min read

Marathon runner holding a steady, patient pace on a long city road.Train

How to Run a Sub-4-Hour Marathon

A sub 4 hour marathon is 5:41 per km, 9:09 per mile. Get the pace, splits, long-run build, and a realistic sub 4 hour marathon training plan. Free, no signup.

Updated Jul 20268 min read

Serious amateur marathoner holding a brisk, controlled goal pace on an open road.Train

How to Run a Sub-3:30 Marathon

A sub 3:30 marathon is 4:58 per km, 8:00 per mile. Get the pace, splits, mileage, and a sub 3:30 marathon training plan built around goal pace. Free, no signup.

Updated Jul 20268 min read

Elite-amateur marathoner driving a hard, relentless pace on an open road.Train

How to Run a Sub-3-Hour Marathon

A sub 3 hour marathon is 4:16 per km, 6:52 per mile. Get the pace, the splits, the weekly mileage, and how to fuel past 30 km. Free predictor, no signup.

Updated Jul 20268 min read

Marathoner pushing a hard, controlled qualifying effort on an open road.Predict

Boston Marathon Qualifying Times by Age

Boston Marathon qualifying times by age and gender, plus the real cutoff buffer you need to actually get in. Check your goal against your standard. Free, no signup.

Updated Jul 202610 min read

Runner wearing a GPS sports watch mid-run on an open outdoor trail.Predict

Is the Garmin Race Predictor Accurate?

Is the Garmin race predictor accurate? For a 5K, often close. For a marathon, it leans too fast. See what it uses, where it drifts, and a free fix, no signup.

Updated Jul 20268 min read

Runner wearing a GPS sports watch during a steady outdoor endurance run.Predict

Is the COROS Race Predictor Accurate?

Is the COROS race predictor accurate? EvoLab splits your fitness four ways but still drifts by distance. See where it misses, plus a free fix, no signup.

Updated Jul 20268 min read

Runner wearing a wrist smartwatch during an outdoor run, screen unreadable.Predict

Can the Apple Watch Predict Your Race Time?

Apple watch race predictor truth: the watch shows a Cardio Fitness (VO2 max) number, not a finish time. See what it can and cannot tell you. Free, no signup.

Updated Jul 20268 min read

Runner moving at a relaxed, easy aerobic effort on an open outdoor path.Train

Heart Rate Zones for Running, Explained

Heart rate zones running guide: the 5 zones by percent of max heart rate, what each one does, and how to set yours with the talk test. Free, no lab, no signup.

Updated Jul 20269 min read

Runner moving at a relaxed, conversational pace on a quiet morning trail.Train

Zone 2 Running: The Complete Guide

Zone 2 running training, explained: how slow easy running should feel, why it builds your aerobic base, and how much of your week it should be. Free, no signup.

Updated Jul 20269 min read

Masters-age runner moving at a relaxed, easy aerobic pace outdoors.Train

What Should Your Zone 2 Heart Rate Be by Age?

Zone 2 heart rate by age: a clean by-age chart, why the formulas are only a starting point, and how to refine your real Zone 2 with field tests. Free, no signup.

Updated Jul 20268 min read

Runner holding a steady, comfortably hard tempo pace on an open road.Train

Lactate Threshold Training for Runners

Lactate threshold training for runners: what threshold is, why it predicts your race time, how to find your pace, and the workouts that raise it. Free, no signup.

Updated Jul 20268 min read

Runner pushing an all-out final effort during a hard training test.Train

The Max Heart Rate Myth (220 Minus Age)

Max heart rate running guide: why 220 minus age is wrong for most runners, the real spread by age, and how to find your true max safely. Free, no signup.

Updated Jul 20269 min read

Runner moving along a high mountain trail with thin, high-altitude air.Race day

How Altitude Changes Your Race Time

Altitude running pace adjustment, made simple. See how thin air slows your race, the rough penalty by elevation, and what acclimating can fix. Free, no signup.

Updated Jul 20269 min read

Runner holding a steady pace on a gym treadmill under bright indoor lighting.Race day

Treadmill vs Outdoor Pace: The Real Conversion

Treadmill pace vs outdoor running: a flat belt is a little easier, and a 1 percent incline matches the open road. See the clean conversion table. Free, no signup.

Updated Jul 20268 min read

Runner in winter layers running along a frosty road with visible breath.Race day

Does Cold Weather Slow Your Running Pace?

Running in cold weather pace, explained: the temperature sweet spot for racing, what cold really costs you in seconds, and how to dress for it. Free, no signup.

Updated Jul 20269 min read

Trail runner navigating a rocky, root-covered forest path.Race day

Trail vs Road: Why Your Pace Doesn't Transfer

Trail running pace vs road: why off-road pace runs slower, how surface and climbing add time, and why you should pace trails by effort. Free, no signup.

Updated Jul 20269 min read

Runner moving through thick morning humidity with a sweat-soaked shirt.Race day

Dew Point: The Hidden Number That Wrecks Your Pace

Dew point running pace, explained: why dew point beats temperature, the danger thresholds, and how to adjust your pace on a humid day. Free, no signup.

Updated Jul 202610 min read

Runners of clearly different ages racing together on an open road.Predict

Age-Grading Explained: Compare Your Time at Any Age

Age graded running calculator basics: what an age-graded percentage means, how to read your score, and the bands from local to world class. Free, no signup.

Updated Jul 20268 min read

Diverse group of runners starting a timed 5K race in a park.Predict

What's a Good 5K Time by Age?

A good 5K time by age and gender, with real race data for average and good times across every decade. See where you stand and find your own ceiling. Free, no signup.

Updated Jul 20268 min read

Pack of runners holding a hard, even effort down a city street.Predict

What's a Good 10K Time by Age?

Good 10K time by age and gender with real benchmarks for average and good finishes every decade. See where you stand. Free, no signup.

Updated Jul 20268 min read

Large field of half marathon runners spread across a city bridge.Predict

What's a Good Half Marathon Time by Age?

A good half marathon time by age and gender, with real benchmark data for average and good finishes across every decade. Find your own ceiling. Free, no signup.

Updated Jul 20269 min read

Marathon runners moving through a city street course in a large field.Predict

What's a Good Marathon Time by Age?

Good marathon time by age and gender with real data for average and good finishes every decade. See where you stand. Free, no signup.

Updated Jul 202610 min read

Diverse crowd of marathon finishers of different ages crossing the line.Predict

Average Marathon Time by Age and Gender

The real average marathon time by age and gender, with median and percentile finish times from 34 million results. See where you sit in the pack. Free, no signup.

Updated Jul 20269 min read

True beginner runner mixing short jogging bursts with walking on a park path.TrainNew

How Long Does It Take to Train for a 5K?

How long to train for a 5K? Timelines for new, returning, and experienced runners and what sets the clock. Free race predictor, no signup.

Updated Jul 20269 min read

Runner extending an easy long run along an open suburban road.TrainNew

How Long Does It Take to Train for a 10K?

How long to train for a 10k depends on your base. See realistic timelines for runners who can run a 5k, are returning, or train often. Free, no signup.

Updated Jul 20269 min read

Runner deep into a long endurance training run on a quiet country road.TrainNew

How Long Does It Take to Train for a Half Marathon?

How long to train for a half marathon depends on your long run. See realistic timelines by base and the minimum safe runway to reach 13.1 miles. Free, no signup.

Updated Jul 20269 min read

Runner lacing up running shoes on a porch before a scheduled run.TrainNew

How Many Days a Week Should You Run?

How many days a week should I run? Most runners need 3 to 5, scaled to goal and experience. See the chart and why steady weeks win. Free predictor, no signup.

Updated Jul 20268 min read

Runner cruising an easy aerobic base run along a quiet open road.TrainNew

Base Building: The Phase Most Runners Skip

Base building in running: what the phase builds, how long it lasts by goal distance, and why skipping it caps speed work. Free, no signup.

Updated Jul 20269 min read

Ultrarunner moving along a rugged mountain trail during a long effort.TrainNew

Your First 50K: Bridging the Gap From Marathon to Ultra

First 50K ultramarathon training for marathon runners: volume, long runs, fueling, and pace changes to bridge the gap safely. Free, no signup.

Updated Jul 20268 min read

Runner holding a steady, easy pace along a long open road.TrainNew

How Many Miles a Week Should You Run?

How many miles per week should I run? Most runners need 20 to 50, scaled to goal distance. See the chart and the safe way to add them. Free, no signup.

Updated Jul 202610 min read

Runner doing a guided hip strength exercise in a physiotherapy studio.TrainNew

Return to Running After Injury: A Safe, Staged Comeback

A return to running after injury plan: a staged walk-to-run schedule, green-light readiness criteria, and the mistakes that cause re-injury. Free, no signup.

Updated Jul 202610 min read

Runner enjoying a relaxed, easy shakeout run during a lighter week.TrainNew

Deload Weeks: Why Cutting Back Makes You Faster

Deload week running explained: cut volume 20 to 40 percent every 3 to 4 weeks so adaptation catches up. See the chart and why it works. Free, no signup.

Updated Jul 202610 min read

Runner performing a hip strengthening exercise in a physio-style gym.TrainNew

Runner's Knee: Causes, Fixes, and How to Prevent It

Runner's knee is the most common running injury. Learn what causes patellofemoral pain, the fixes that work, and how to prevent it. Free, no signup.

Updated Jul 20269 min read

Runner doing a resistance-band lateral walk to strengthen hips and glutes.TrainNew

IT Band Syndrome: Why It Flares and How to Come Back

IT band syndrome in runners causes sharp pain on the outside of the knee. Learn why it flares, the fixes that work, and how to return. Free, no signup.

Updated Jul 20269 min read

Marathon runner squeezing an energy gel into their mouth mid-race.Race dayNew

How Many Gels for a Marathon? Carbs-Per-Hour Guide

How many gels for a marathon do you need? Use the carbs-per-hour research and your finish time to build a real gel plan. Free race predictor, no signup.

Updated Jul 20268 min read

Runner eating a large bowl of pasta at home the night before a race.Race dayNew

Carb Loading Before a Marathon: The Simple Math

Carb loading before a marathon made simple. Learn the grams-per-kg target, the best 1 to 3 day window, and what to eat. Free race predictor, no signup.

Updated Jul 20268 min read

Runner in race gear eating a simple breakfast at a kitchen table.Race dayNew

What to Eat Before a Race: The Morning Plan

What to eat before a race, hour by hour. Get the carb target, the timing, and the foods to skip so your stomach cooperates. Free predictor, no signup.

Updated Jul 20268 min read

Marathon runner drinking from a handheld soft flask on an open road.Race dayNew

Marathon Hydration Strategy: How Much to Drink

Marathon hydration strategy made simple. Learn how much to drink, when to use sodium, and how to avoid both dehydration and overdrinking. Free predictor.

Updated Jul 20268 min read

Half marathon runner taking an energy gel near the halfway point.Race dayNew

Half Marathon Fueling: Do You Even Need Gels?

Half marathon fueling made simple. Find out if you need gels, how many to carry, and how your finish time changes the answer. Free predictor, no signup.

Updated Jul 20268 min read

Runner mid-stride on an open road showing a quick, light foot strike.TrainNew

Running Cadence 180: Is the Magic Number Real?

Running cadence 180 steps per minute gets called ideal, but real data shows a wide range. See where the number came from and how to raise yours free.

Updated Jul 20268 min read

Runner holding a relaxed, efficient stride with a natural arm swing.TrainNew

How to Improve Running Economy (Proven Methods)

How to improve running economy with the training methods backed by real studies. See what running economy is, why it beats VO2 max, and what works. Free.

Updated Jul 20268 min read

Runner performing a heavy barbell back squat in a gym.TrainNew

Strength Training for Runners: What Actually Works

Strength training for runners made simple. See the key lifts, how often to train, and the real studies on injury and speed. Free race predictor, no signup.

Updated Jul 20268 min read

Runner accelerating through a fast, relaxed stride on a track.TrainNew

Running Form Drills That Actually Help (Backed by Research)

Running form drills worth your time, backed by real studies, not just tradition. See what each one fixes and how to add them free, no signup needed.

Updated Jul 20268 min read

Runner cross training on a road bike along a quiet paved route.TrainNew

Cross Training for Runners: What Actually Transfers

Cross training for runners, ranked by what really transfers to your running. See cycling, swimming, and pool running compared. Free, no signup needed.

Updated Aug 20268 min read

Beginner runner walking then breaking into a jog on a park path.TrainNew

Couch to 5K Training Plan: Your 8-Week Walk-to-Run Guide

A couch to 5k training plan you can actually finish: the 8-week walk-to-run schedule, why week 3 feels hardest, and how to keep going. Free, no signup.

Updated Aug 20268 min read

Marathon runner surging ahead of the pack in a crowded race start.Race dayNew

First Marathon Mistakes That Cost Runners the Most

The most common first marathon mistakes: going out too fast, no fuel plan, peaking too early, and new gear on race day. Free finish predictor, no signup.

Updated Aug 20268 min read

Beginner runner in ordinary clothing on a long training run outdoors.TrainNew

Beginner Half Marathon Training Plan: A 12-Week Build

A beginner half marathon training plan: the base you need first, a realistic 12-week build, and a fair first goal. Free half marathon predictor, no signup.

Updated Aug 20268 min read

True beginner walking then jogging for the first time in a park.TrainNew

How to Start Running: A Gentle Guide for True Beginners

How to start running from zero: the gentle walk-to-run on-ramp, what week 1 feels like, and how often beginners train. Free 5K predictor, no signup needed.

Updated Aug 20268 min read

Runner racing a 5K at hard, near-maximum controlled effort on the road.Race dayNew

How to Pace a 5K: Even Effort vs. the Fast-Start Trap

Learn how to pace a 5K with near-even effort, a small controlled fast start, and km-by-km targets. Free 5K time predictor, no signup, no watch needed.

Updated Aug 20268 min read

Runner holding steady controlled discomfort through the middle of a 10K.Race dayNew

How to Pace a 10K: Controlled Discomfort in Thirds

Learn how to pace a 10k by splitting the race into thirds, avoiding the mid-race sag, and holding controlled discomfort. Free 10K time predictor, no signup.

Updated Aug 20268 min read

Half marathon runner holding a patient, controlled pace in the early miles.Race dayNew

How to Pace a Half Marathon: Even to Slight Negative

Learn how to pace a half marathon with even or slightly negative splits and strict first-5K discipline. Free half marathon time predictor, no signup needed.

Updated Aug 20268 min read

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