Sports Science Evidence Base

Every article is grounded in peer-reviewed research and linked to a relevant calculator — so you can apply the science to your own numbers immediately.

Health Science

Caffeine Half-Life: Exactly How Long Caffeine Stays in Your System

8 min readCaffeine Half-Life Calculator
Sleep Science

Sleep Cycles Per Night: How Many You Need and Why It Matters

9 min readSleep Cycle Calculator
Performance Science

VO₂max by Age: Complete Chart, Norms, and What Your Score Means

10 min readVO₂max Calculator
Cycling Science

FTP Cycling: What Is a Good Score? (W/kg Chart by Ability Level)

9 min readFTP Calculator
Strength Science

1RM Percentage Chart: How to Use Your One-Rep Max for Training

9 min read1RM Calculator
Cycling Science

1x vs 2x Drivetrain: The Engineering Mathematics Every Cyclist Should Understand

5 min readCycling Gear Ratio Calculator
Athletic Performance

ACL Tears Are Largely Preventable. Most Teams Still Are Not Doing the 20 Minutes That Proves It.

5 min read1RM Calculator
Athletic Performance

Active Recovery at 35–40% VO₂max Clears Lactate Three Times Faster Than Rest. Here Is Why It Works.

5 min readRecovery Need Estimator
Athletic Performance

Elite Sprinters Almost Never Have Two Copies of the ACTN3 XX Genotype. Elite Endurance Athletes Almost Always Do. This Is Not Coincidence — It Is the Most Replicated Sports Genomics Finding in the Literature.

5 min readFor athletes calculating their maximum natural muscle potential from structural measurements — a evidence-based ceiling that doesn't require a genetic test:
Sports Science

Why Your Caloric Deficit Stops Working After 8 Weeks — and It's Not a Willpower Problem

5 min readIf you want to calculate your current TDEE with activity-level breakdowns — and recalculate at intervals during a cut phase as body weight and training load change:
Athletic Performance

The Autoimmune Protocol (AIP) Diet: What Athletes With Inflammatory Conditions Need to Know

5 min readPaleo Diet Macros Calculator
Athletic Performance

How Long After Drinking Is It Safe to Train? The Pharmacology Most Athletes Get Wrong.

5 min readIf you want to calculate an athlete's personal BAC elimination curve — including clearance timeline to zero BAC, rehydration window, and sleep quality impact by drink count and body weight:
Athletic Performance

Two Drinks After Training Aren't Just Empty Calories — They're Actively Sabotaging Your Tendons

5 min readEmpty Calories from Alcohol Calculator
Athletic Performance

Alcohol Has 7 Calories Per Gram. That's Not Even the Worst Part for Body Composition.

5 min readIf you want to calculate the exact caloric load and ethanol content from your weekly drinking pattern — and see how it maps against your fat loss deficit:
Athletic Performance

The Physiology of "Just a Few Drinks" — What's Actually Happening to Your Recovery

5 min readIf you want to understand how quickly your body metabolises alcohol based on weight, sex, drink count, and time — and when you'll be fully cleared:
Athletic Performance

Same Drink, 30% Higher BAC: The Physiology Behind Why Female Athletes Eliminate Alcohol Differently

5 min readAlcohol Metabolism Calculator
Cycling Science

Why Your Cycling Calorie Calculator Lies at Altitude — And What to Do About It

5 min readCycling Calorie Calculator
Athletic Performance

Altitude Training Masks Don't Simulate Altitude. Here's What They Actually Do.

5 min readVO2max Calculator
Athletic Performance

Why Elite Runners Spend 4 Weeks at 2,400m Before Major Races — The Physiology of Altitude Adaptation

5 min readIf you want to calculate recovery readiness scores after an altitude camp — where accumulated training stress and acclimatisation demand are significantly higher than sea-level training:
Athletic Performance

Why Fit Athletes Collapse Above 3,000m (And How to Prevent It)

5 min readOutdoor Safety Risk Calculator
Athletic Performance

Android vs Gynoid Fat: Why Where You Store Fat Matters More Than How Much You Have

5 min readBody Fat Percentage Calculator
Athletic Performance

Vitamin C Is the Most Important Supplement for Tendon Health. But You Are Probably Taking It at Completely the Wrong Time — and the Difference Is Not Trivial.

5 min readFor athletes calculating the daily collagen dose and timing protocol for joint and tendon repair — separating the cofactor role of vitamin C from its adaptation-blunting antioxidant effect:
Athletic Performance

The Light in Your Phone is Delaying Your Sleep by 90 Minutes. That's Your Recovery Window Gone.

5 min readMelatonin Timing Calculator
Athletic Performance

The Adaptogen That Actually Has RCT Evidence: KSM-66 Ashwagandha and What It Does to Athletes

5 min readRecovery Need Estimator
Athletic Performance

Most Elite Athletes Retire Financially Unprepared. The Problem Starts With How Sports Treats Peak Earning Years.

5 min readThe same compound growth mathematics that governs training adaptation applies to long-term financial accumulation — and the athlete's compressed earning window makes starting earlier disproportionately more valuable.
Athletic Performance

The Athlete's Heart: Why Your Enlarged Cardiac Chambers Are a Feature, Not a Bug

5 min readHeart Rate Zone Calculator
Athletic Performance

Your BCAA Supplement Is Missing 6 Essential Amino Acids — and That Gap Costs You Muscle

5 min readProtein Intake Calculator
Athletic Performance

Exercise Is the Most Potent Legal Stimulus for Brain Growth That Exists. The Mechanism Is Specific.

5 min readFor athletes tracking VO₂max and aerobic fitness levels as a quantifiable target for the exercise dose range associated with sustained BDNF-mediated cognitive benefits:
Athletic Performance

The Plant Alkaloid With Metformin-Like Effects — What Athletes Need to Know

5 min readKeto Macro Calculator
Athletic Performance

Why Your Muscles Fail at High Intensity — And the Amino Acid That Delays It.

5 min readIf you coach athletes in middle-distance running, rowing, or cycling events where the 1–10 minute glycolytic window determines performance:
Athletic Performance

Before the Alarm Clock Existed, Humans Slept in Two Phases — And Athletes Might Benefit From Knowing Why

5 min readSleep Cycle Calculator
Strength & Muscle

Building Muscle at 20% of Your 1RM: The Physiology Behind Blood Flow Restriction Training.

5 min readFor athletes and coaches needing to set accurate BFR working loads based on 20–40% of true 1RM:
Athletic Performance

The Equation You're Using to Calculate Calorie Needs Is Wrong for 20% of People — By Design

5 min readIf you want to build structured daily meal distributions from an empirically-calibrated calorie target — adjusting as body weight response reveals your true metabolic rate:
Health Science

Your Body Composition Reading Is Only as Accurate as the Method You Trust — Here's the Error Each One Carries

5 min readIf you want a field-based body fat estimate using circumference measurements — with error range context and the conditions under which the estimate is most accurate:
Athletic Performance

Why Body Fat Percentage Is a More Useful Health Marker Than BMI — and How to Measure It Without Expensive Equipment

5 min readIf you want to calculate your body fat percentage using the US Navy circumference method — with body fat category classification and an estimate of your fat-free mass:
Cycling Science

Masters Athletes Have Lower Fracture Risk Than Sedentary Peers — Unless They're Doing the Wrong Sports.

5 min readFor masters athletes assessing their seasonal vitamin D status and sun exposure requirements — a key input in the calcium absorption and bone mineral density equation:
Athletic Performance

The Forgotten Mineral That Lowers SHBG and Raises Free Testosterone

5 min readVitamin D Calculator
Athletic Performance

The Pre-Milk Supplement That High-Load Athletes Should Know About

5 min readProtein Intake Calculator
Athletic Performance

Your Autonomic Nervous System Has a Resonance Frequency. Training It Changes Your Heart Rate Variability More Than Most Supplements.

5 min readHeart Rate Zone Calculator
Athletic Performance

Caffeinated Energy Gels Work Best in the Second Half of a Race — But Most Athletes Use Them Earliest. The Adenosine Science Behind Why Timing Is Everything.

5 min readFor athletes building a timed gel schedule with strategic placement of caffeinated vs non-caffeinated gels across a race:
Athletic Performance

Coffee Before Training Will Dehydrate You — Except It Won't

5 min readCaffeine Half-Life Calculator
Health Science

The Maths of Four Coffees: Why Caffeine Accumulates More Than You Think

5 min readCaffeine Half-Life Calculator
Health Science

The 200mg Caffeine Limit in Pregnancy Is Evidence-Based. The Reasoning Behind It Is More Important Than the Number.

5 min readCaffeine Metabolism Tracker
Athletic Performance

The '6 Hours Before Bed' Caffeine Rule Understates the Problem for Half the Population.

5 min readFor athletes and coaches calculating optimal sleep timing and wake windows based on sleep cycle completion:
Athletic Performance

Your Pre-Workout Caffeine Isn't Just Waking You Up — It's Reprogramming Your Nervous System

5 min readCaffeine Pre-Workout Calculator
Athletic Performance

Your Pre-Workout Caffeine Isn't Working — And the Reason Is More Interesting Than Tolerance

5 min readIf you want to calculate your optimal caffeine dose based on bodyweight, habitual intake, event duration, and timing — including a cycling protocol to preserve the ergogenic effect:
Athletic Performance

You've Been Using Caffeine Wrong Before Your A-Race — The Sensitivity Reset Protocol

5 min readCaffeine Metabolism Tracker
Cycling Science

Eating the Same Macros Every Day Is Leaving Performance Gains and Fat Loss on the Table Simultaneously.

5 min readFor athletes calculating precise macro targets on low-carbohydrate rest days within a carb cycling protocol — where a near-keto macro split optimises fat oxidation and insulin sensitivity:
Athletic Performance

Carbohydrate Loading Is Not Just 'Eating More Pasta'. The Protocol That Actually Maximises Race-Day Glycogen.

5 min readFor athletes building a carbohydrate-loading meal plan across the 48-hour pre-race window — distributing 9–12g/kg carbohydrate across 5–6 meals at a custom high-carb macro split:
Athletic Performance

The Shoe That Changed Marathon Times Overnight — And What Actually Makes It Work

5 min readRunning Pace Calculator
Athletic Performance

Your Muscles Weren't the First to Fail at Hour 3. Your Brain Made That Decision First.

5 min readMacro Meal Generator
Athletic Performance

CGM for Non-Diabetic Athletes: What Your Postprandial Glucose Is Actually Telling You

5 min readMacro Meal Generator
Athletic Performance

Chews vs Gels vs Liquid Carbohydrate: Which Fuelling Format Wins on Race Day?

5 min readEnergy Gel Calculator
Athletic Performance

Plant-Based Athletes Optimising Omega-3 Through Chia Are Getting a Worse Deal Than They Think

5 min readProtein Intake for Muscle Gain
Sports Nutrition

Exercise Is Medicine — But Only When the Nutritional Context Supports It

5 min readIf you want to generate a personalised nutrition protocol for a specific chronic condition — including type 2 diabetes, cardiovascular disease, hypertension, or metabolic syndrome — with macronutrient targets adjusted for activity level and bodyweight:
Athletic Performance

Morning People and Evening People Are Not Just Personality Types. They Have Measurably Different Hormonal Environments at 6am vs 6pm — and Most Athletes Are Training at the Wrong One.

5 min readFor athletes calibrating heart rate training zones — accounting for the time-of-day confounding that shifts max HR and zone thresholds between morning and afternoon testing:
Athletic Performance

It's Not Just When You Eat — It's When Your Circadian Clock Expects You To

5 min readIntermittent Fasting Window Calculator
Athletic Performance

Cluster Sets: The Intraset Rest Trick That Lets You Lift Heavier for Longer

5 min read1RM Calculator
Athletic Performance

Coeliac Disease in Athletes: The Silent Deficiency That's Wrecking Performance

5 min readChronic Disease Nutrition Guide
Cycling Science

Your Watts Tell You What. Your Power Profile Tells You Who.

5 min readFTP Calculator
Athletic Performance

Adults Have Brown Fat. Cold Exposure Activates It. Here Is What That Actually Does to Body Composition.

5 min readBody Fat Percentage Calculator
Athletic Performance

Cold Water Immersion Recovers You Faster. It Also Blunts Hypertrophy. Here's When Each Outcome Matters.

5 min readFor coaches quantifying training stress and deciding when recovery intervention vs adaptation protection should take priority:
Athletic Performance

Winter Training Doesn't Just Feel Harder. The Cold Is Actively Working Against Your Physiology.

5 min readOutdoor Safety Risk Calculator
Athletic Performance

Collagen Has a DIAAS Score of Zero. Here's Why Serious Athletes Should Still Take It.

5 min readCollagen Dosage for Joints
Athletic Performance

The One Supplement Protocol Most Athletes Have Never Heard Of — With Solid Evidence Behind It

4 min readIf you want to calculate your personalised collagen dosing based on bodyweight, injury history, and training load — including timing guidance for the pre-exercise protocol:
Cycling Science

You're Riding the Wrong Chainring — Why Most Sportive Cyclists Should Drop to Compact

5 min readCycling Gear Ratio Calculator
Cycling Science

The 1% Principle in Elite Sport: Why Consistent Marginal Gains Beat Annual Training Overhauls

5 min readThe same mathematics that governs compound interest in investing governs training adaptation accumulation — consistent marginal gains compound non-linearly, and reversal events cost disproportionately.
Athletic Performance

Compression Tights: Legitimate Recovery Tool or Expensive Placebo?

5 min readRecovery Need Estimator
Athletic Performance

If You're Lifting and Running in the Same Session, Molecular Biology Explains Why One Adaptation Is Undermining the Other — and What Session Ordering Can Do About It.

5 min readFor athletes planning nutrient timing across concurrent training days — calculating meal composition to optimally bridge endurance and resistance sessions and attenuate the AMPK interference window:
Sports Science

The Strongest People in the World Train Two Qualities at Once. Here's Why Conjugate Periodisation Defies Everything You Were Taught About Programming.

5 min readWilks Score Calculator
Athletic Performance

Your Ferritin Came Back Low. You Started Iron Supplements. Three Months Later — Still Low.

5 min readIron Needs Calculator
Athletic Performance

The Hormonal Spike That Happens Every Morning — And Why It Matters for Athletes Who Train Early

5 min readSleep Cycle Calculator
Cycling Science

Every Road Bike Ships With the Wrong Crank Length for Most Riders

5 min readCycling Gear Ratio Calculator
Athletic Performance

Your Turmeric Latte is Doing Almost Nothing. Here's Why Curcumin Delivery Form Changes Everything.

5 min readCollagen Dosage for Joints
Athletic Performance

Cyclical Keto for Hybrid Athletes: Getting Fat Adaptation Without Sacrificing High-Intensity Power

5 min readKeto Macro Calculator
Cycling Science

You Can Save More Watts by Tucking Your Elbows Than by Buying Aero Wheels. The Physics Proves It.

5 min readCycling Calorie Calculator
Cycling Science

Most Cyclists Are Fuelling Their Rides Completely Wrong — Here's the Calculation That Changes Everything

5 min readIf you want to calculate your actual calorie expenditure for a specific ride based on power output, rider weight, elevation, and drafting conditions:
Cycling Science

Most Cyclists Under-Fuel Long Training Rides by 40–60%. The Bonk That Follows Is Not a Sign of Low Fitness. It Is a Predictable Consequence of a Calculable Fuelling Deficit.

5 min readFor cyclists calculating gel requirements and a timed fuelling schedule for long training rides and events — ensuring carbohydrate intake matches expenditure rate before the glycogen depletion threshold is crossed:
Athletic Performance

Two Athletes. Identical Caffeine Protocol. Completely Different Results. Here's Why.

5 min readIf you want to model your personal caffeine clearance curve based on metaboliser type (fast/intermediate/slow), dose, and timing — including when caffeine concentration drops below sleep-disrupting threshold:
Cycling Science

Why Elite Cyclists Are Eating Dark Chocolate Before Time Trials (It's Not What You Think)

5 min readCycling Calorie Calculator
Athletic Performance

Losing 2% of Body Weight in Sweat Reduces Strength by Up to 8%. The Numbers Coaches Ignore.

5 min readElectrolyte Loss Calculator
Athletic Performance

The Week You Stop Training Is the Week Your Body Gets Stronger — If You Do It Right

5 min readRecovery Need Estimator
Athletic Performance

Muscle Memory Is Not a Metaphor. Here's the Cellular Mechanism That Makes Retraining Faster Than Building From Scratch.

5 min readFor coaches managing training load in the critical return-to-training window after a detraining period — where accumulated fatigue from rapid reloading can exceed connective tissue readiness:
Sports Nutrition

The Third-Trimester Brain Surge: Why 200mg of DHA Is the Floor, Not the Target

5 min readPregnancy Nutrient Calculator
Athletic Performance

The Dietary Inflammatory Index: Is Your Diet Fuelling Recovery or Systemic Inflammation?

5 min readZone Diet Blocks Calculator
Athletic Performance

The Most Overlooked Legal Performance-Enhancing Intervention in Endurance Sport Costs Less Than £2 Per Serving and Has Been in Your Kitchen All Along.

5 min readFor runners and cyclists tracking pace economy across training blocks — and determining whether performance changes reflect fitness gains or supplementation effects:
Athletic Performance

You Might Be Eating Enough Protein — But Not Absorbing Enough. Digestive Enzymes Explain the Gap.

5 min readProtein Intake Calculator
Sports Nutrition

The Soreness You Feel 48 Hours After Training Is Not a Sign of a Good Workout. It Is an Inflammatory Cascade.

5 min readRecovery Need Estimator
Athletic Performance

There Is a Hard Ceiling on How Much Carbohydrate Your Gut Can Absorb From a Standard Gel. Breaking Through It Requires a Second Transporter That Most Gel Formulations Don't Engage.

5 min readFor athletes calculating whether their event duration requires 60g/hr (single-transporter) or 60–90g/hr (dual-transporter) fuelling — and identifying the right gel formulation before race day:
Strength & Muscle

Same Rep Range Every Session? Research Said Stop Doing That 20 Years Ago.

5 min readWilks Score Calculator
Athletic Performance

Specialising Your 10-Year-Old Is the Fastest Route to a 14-Year-Old Who Quits Sport Forever

5 min readPediatric Growth & Dosage Calculator
Athletic Performance

The Exercise That Reduces Hamstring Injury Risk by 51% — And Almost Nobody Does It

5 min readOne Rep Max (1RM) Calculator
Athletic Performance

Drinking More Water During a Race Won't Fix This — And Sometimes Makes It Worse

5 min readIf you want to calculate your estimated sweat rate, sodium loss per hour, and fluid replacement targets for your specific conditions:
Cycling Science

Endurance Athletes Are Still Under-Consuming Protein — And the Science Shows It Costs Them Speed.

5 min readProtein Intake Calculator
Athletic Performance

Energy Gels vs Real Food in Ultra-Endurance Events: The Physiology Is Identical. The Practical Differences Are Not.

5 min readFor athletes calculating gel requirements for the gel-dominant phase of long events before transitioning to real food:
Athletic Performance

Taking an Energy Gel Without Water Isn't Just Uncomfortable — It Physiologically Delays the Carbohydrate Reaching Your Muscles. Here Is Exactly Why.

5 min readFor athletes planning gel intake alongside fluid requirements — ensuring each gel is paired with adequate water to prevent the osmolality-driven GI distress that ends races:
Sports Science

Textbooks Teach ATP-PCr, Glycolysis, and Oxidative Metabolism as Three Separate Systems. They Are Not. Understanding Why Changes How You Should Design Training Across All Sports.

5 min readFor runners modelling race pace across distances and calculating optimal split strategies based on energy system-appropriate pacing targets:
Athletic Performance

The Training Day That Destroys Kidneys: What Every Coach Needs to Know About Rhabdo

5 min readOutdoor Safety Risk Calculator
Athletic Performance

Exogenous Ketones: What the Evidence Actually Shows for Athletic Performance

5 min readKeto Macro Calculator
Sports Nutrition

Fasted Cardio Burns More Fat During the Session. It Does Not Burn More Fat Overall.

5 min readFTP Calculator
Health Science

Your Natural Muscle Ceiling Is Not Where You Think It Is — The Science of Genetic Potential

5 min readIf you want to calculate your current FFMI and see how far you are from your natural muscle ceiling — using both the FFMI model and the Casey Butt structural formula:
Athletic Performance

Taking Your First Energy Gel at the Start Line Is a Mistake. So Is Waiting Until You Feel Hungry. The Science of Pre-Emptive Fuelling.

5 min readFor athletes building a race-day fuelling schedule with evidence-based first-gel timing and automatically spaced subsequent intervals:
Wealth Optimization

Should a Fitness Business Buy or Lease Its Space? The Financial Calculation Most Coaches Skip.

5 min readIf you want to model the monthly repayment on a commercial property purchase — and compare it directly against current lease costs to calculate the ownership break-even point:
Strength & Muscle

This Training Device Automatically Overloads Your Eccentric Phase Beyond 1RM — No Spotter Required

5 min read1RM Calculator
Athletic Performance

Foam Rolling Before a Run Does Not Improve Performance. But the Runners Who Skip It Pay a Different Price — and the Science Explains Both Sides of That Trade-Off.

5 min readFor runners calculating training paces and monitoring how movement restriction affects their ability to sustain target intensities:
Cycling Science

Most Amateur Cyclists Are Riding in the Wrong Gear — Here's the Physics Behind Why

4 min readIf you want to calculate your exact gear ratios, optimal cadence zones, and projected speed for any chainring/cassette combination:
Athletic Performance

The HERITAGE Study Reveals Why Two Athletes on Identical Training Plans Get Completely Different Results

5 min readGenetic Potential Calculator
Athletic Performance

Every Endurance Athlete Knows Protein Matters. Almost None Know Their Biggest Immune Nutrient Is Quietly Depleted at the Finish Line.

5 min readProtein Intake Calculator
Athletic Performance

Athletes Have Been Using Glycaemic Index Wrong for 40 Years

5 min readMacro Meal Generator
Athletic Performance

Glycerol Hyperhydration: The Pre-Race Fluid Trick Most Athletes Have Never Heard Of

5 min readElectrolyte Loss Calculator
Athletic Performance

The Bonk Is Not Random. It Is Predictable. Every Endurance Athlete Who Has Hit the Wall Did So Because of a Calculable Carbohydrate Deficit — Not Because They Didn't Train Hard Enough.

5 min readFor athletes calculating the carbohydrate intake and gel count required to prevent glycogen depletion — building the pre-emptive fuelling plan before the bonk becomes a late-race problem:
Health Science

Grip Strength Predicts Cardiovascular Death More Accurately Than Blood Pressure. The 140,000-Person Evidence.

5 min readGenetic Potential Calculator — Max Natural Muscle Mass
Athletic Performance

Elite Endurance Athletes Have a Measurably Different Gut. Here's What's in It — and Why It Matters.

5 min readFor athletes and coaches building structured meal plans across different dietary patterns — and wanting to diversify fibre sources across training and rest days:
Athletic Performance

The Most Underused Component of Endurance Race Preparation Is Not a Training Session. It Is Practising Your Nutrition Protocol in Training — and Most Athletes Never Do It.

5 min readFor athletes building the gel protocol they need to practise in training before executing on race day:
Athletic Performance

The Genetic Condition That Makes Iron Supplementation Dangerous for 1 in 200 Athletes

5 min readIron Needs Calculator
Athletic Performance

Athletes Who Train in Heat Gain a Physiological Advantage That Persists in Cool Conditions. Here's the Mechanism.

5 min readFor athletes and coaches calculating sweat-rate-adjusted electrolyte replacement during heat training blocks — particularly as acclimatisation increases hourly fluid and mineral loss:
Athletic Performance

When Core Temperature Crosses 39°C, the Most Important Organ Failing Is Not Your Muscles. It Is Your Gut — and Once the Intestinal Barrier Breaks Down, the Consequences Go Far Beyond GI Cramps.

5 min readFor athletes planning hydration strategy for hot-weather racing — calculating sweat rate and sodium losses to protect both performance and intestinal barrier function:
Athletic Performance

Your 3:30 Marathon Pace Was Built in October. It's June Now. Here's What Changes.

5 min readMarathon Race Predictor
Sports Nutrition

HMB: The Most Misunderstood Muscle Supplement Has a Very Specific Use Case

5 min readProtein Intake Calculator
Athletic Performance

Most Athletes Are Measuring HRV. Most Athletes Are Measuring It Wrong. The Errors That Make Your Morning HRV Score Meaningless — and the Protocol That Makes It Actionable.

5 min readFor athletes quantifying training load and recovery need — giving objective context to what their suppressed or elevated HRV readings are actually reflecting:
Strength & Muscle

There Are Three Proposed Mechanisms of Muscle Growth. One Dominates. The Other Two Are Widely Misunderstood — and One May Not Work the Way the Industry Claims.

5 min readFor coaches and athletes calculating 1RM to set accurate load targets across all rep ranges — ensuring both tension-dominant and metabolic-stress-dominant protocols use the correct percentage of true maximum:
Cycling Science

Altitude Tents Are No Longer Just for Pro Cyclists. Here's What the Evidence Actually Says.

5 min readVO2max Calculator
Cycling Science

There's a Respiratory Limiter in Competitive Cyclists and Runners That Interval Training Never Touches. Most Athletes Don't Know It Exists.

5 min readVO2max Calculator
Athletic Performance

The Intermittent Fasting Mistake That's Silently Undermining Your Training Adaptations

4 min readIf you want to calculate your optimal eating window timing relative to your training schedule — including recommended meal timing and protein distribution:
Strength & Muscle

The Most Widely Taught Breathing Cue in the Weight Room Is Physiologically Backwards. 'Exhale on the Effort' Reduces Spinal Stability at Precisely the Moment You Need It Most.

5 min readFor powerlifters and strength athletes calculating relative strength benchmarks across bodyweights and comparing progress using bodyweight-normalised coefficients:
Athletic Performance

Carbohydrate During Training: The 75-Minute Threshold That Changes Everything

5 min readEnergy Gel Calculator
Strength & Muscle

Your Wilks Score Is Lying to You — Here's the Formula That Replaced It

5 min readWilks Score Calculator
Athletic Performance

Your Ferritin Is Low. You're Taking Iron Supplements. Why Isn't It Working? The Answer Is in the Biology, Not the Dose.

5 min readFor athletes and coaches calculating personalised iron requirements — accounting for training type, sweat loss, and menstrual status — and determining whether supplementation is indicated and at what dose:
Athletic Performance

Runners Who Can't Explain Their Fatigue Should Check This First — Before Blaming Overtraining

5 min readIf you want to estimate your daily iron requirement based on training load, mileage, diet type, and gender — and see whether your current intake is likely to be sufficient:
Athletic Performance

Your Athlete Isn't Burnt Out. Their Thyroid Is Starved of Iron. Here's the Overlooked Mechanism.

5 min readIron Needs Calculator
Sports Nutrition

Keto vs Balanced. High Carb vs High Protein. After 40 Years of Diet Wars and Billions in Research Funding, the Metabolic Ward Data Has a Clear Answer — and It Annoys Everyone.

5 min readFor athletes comparing macro ratio approaches at their specific caloric intake — seeing what keto, balanced, and high-protein splits actually produce in g/day before choosing:
Cycling Science

Two Athletes, Same Zone 2 Target — One Is Undertrained, One Is Overtrained. Here's Why.

5 min readHeart Rate Zone Calculator
Athletic Performance

Fat Adaptation Is Real — But the Research on Keto and Endurance Performance Is Not What You've Been Told

5 min readIf you want to calculate your keto macro targets adjusted for training load, event duration, and fat adaptation phase — including a timeline for metabolic transition:
Athletic Performance

L-Carnitine and Fat Burning: What the Physiology Promises and What the Trials Deliver

5 min readKeto Macro Calculator
Cycling Science

The NO₂ Hack Most Cyclists Ignore: L-Citrulline Malate and the Nitric Oxide Shortcut

5 min readCycling Calorie Calculator
Athletic Performance

LT1, LT2, and MLSS: Why Coaches and Athletes Keep Confusing the Three Thresholds That Define Training Zones

5 min readIf you want to estimate your FTP and build training zones anchored to LT1/LT2 thresholds rather than arbitrary percentages:
Athletic Performance

Lightning Risk for Outdoor Athletes: The Evidence-Based Protocol That Could Save Your Life

5 min readOutdoor Safety Risk Calculator
Athletic Performance

Hitting Your Macro Targets Isn't Enough — How You Distribute Them Across the Day Changes the Outcome

5 min readIf you want to generate a personalised meal plan that distributes your daily macro targets across the right number of meals with training-day and rest-day adjustments:
Athletic Performance

Athletes Are Taking Magnesium for Sleep — But Most Are Using the Wrong Form at the Wrong Time

5 min readIf you want to calculate your personalised magnesium requirement based on training load, sweat rate, diet type, and sleep quality goals:
Athletic Performance

Not All Magnesium Is Equal: Why Threonate Crosses the Blood-Brain Barrier When Glycinate Doesn't

5 min readMagnesium Intake Estimator
Athletic Performance

Low Magnesium Slows Post-Exercise Glucose Uptake. Most Athletes Are Never Told This Connection.

5 min readMagnesium Intake Estimator
Athletic Performance

Your 5K Time Doesn't Predict Your Marathon — And Aerobic Decoupling Explains Why

5 min readMarathon Race Predictor
Athletic Performance

Most Marathon Runners Carry Either Too Many Gels or Too Few. The Calculation That Fixes This Takes About 90 Seconds.

5 min readFor runners calculating exact gel count, carb target, and timing schedule for marathon race day:
Athletic Performance

Marine vs Bovine Collagen: Which Source Actually Works for Athletes?

5 min readCollagen Dosage for Joints Calculator
Athletic Performance

Massage Isn't Just a Luxury. It Signals the Same Mitochondrial Pathways as Exercise. The Evidence Is Striking.

5 min readRecovery Need Estimator
Athletic Performance

A 3:15 Marathon at 55 Might Be More Impressive Than 2:45 at 28. World Masters Athletics Has the Maths.

5 min readMarathon Race Predictor
Athletic Performance

Barry Sears Said 40-30-30. The Mediterranean Diet Says Something Different — And the Data Takes Sides

5 min readZone Diet Blocks Calculator
Athletic Performance

Athletes Are Overdosing Melatonin — The Chronobiology Evidence Says 0.5mg Works Better Than 5mg

5 min readMelatonin Timing Calculator
Athletic Performance

Taking Melatonin at the Wrong Time Makes Jet Lag Worse — Here's the Timing Protocol That Actually Works

4 min readIf you want to calculate the optimal melatonin timing and dosing for your specific travel route, time zone difference, and competition schedule:
Athletic Performance

Training Load Prescription Assumes a 24-Hour Hormonal Cycle. Half of All Athletes Have a 28-Day One. The Gap in Programme Design Is Significant and Largely Unaddressed.

5 min readFor coaches tracking VO₂max estimates across training phases — distinguishing genuine fitness decline from luteal-phase performance decrements driven by elevated core temperature and ventilation:
Athletic Performance

You Were Cognitively Tired Before the Workout Started. That's Why It Felt Impossibly Hard.

5 min readRecovery Need Estimator
Athletic Performance

Two Athletes Take Identical Protein Supplements. One Absorbs 40% More Usable Amino Acids Than the Other. The Difference Is Not the Supplement — It Is the Gut Microbiome Processing It.

5 min readFor athletes calculating their protein intake targets — understanding both the dose required and how meal distribution affects net amino acid availability:
Athletic Performance

Barefoot Running Science: What Harvard Got Right — And What the Minimalist Movement Got Wrong

5 min readRunning Pace Calculator
Strength & Muscle

You're Leaving Hypertrophy on the Table After Every Set. The Myo-Reps Method Fixes That.

5 min readOne Rep Max (1RM) Calculator
Athletic Performance

Most Athletes Are Breathing Wrong — and It's Limiting Performance in Ways They Can't Measure.

5 min readFor runners identifying the easy and aerobic pace zone where nasal-only breathing training is practical and beneficial:
Athletic Performance

How Much Muscle Can You Actually Build Each Year? The Rate-Based Model the Fitness Industry Obscures

5 min readGenetic Potential Calculator
Athletic Performance

41% of Elite Endurance Athletes Eat Gluten-Free. The Science Says Most Probably Should Not.

5 min readPaleo Diet Macros
Sports Nutrition

You Train for One Hour and Sit for Fourteen. That Gap Is Destroying Your Fat Loss Results.

5 min readBody Fat Percentage Calculator
Cycling Science

The Fastest Time Trial Riders Don't Go Hard Early — And the Physics Proves Why

5 min readFTP Calculator
Athletic Performance

Why Elite Athletes Are Targeting NAD⁺ — And Whether the Science Holds Up

5 min readFTP Calculator
Athletic Performance

Powerlifters Periodise Their Training Across the Year. Most Forget to Periodise Their Nutrition. Here's What an Optimised Strength Nutrition Calendar Looks Like.

5 min readMacro Meal Generator
Athletic Performance

You're Hitting Your Protein Targets and Still Under-Recovering. Omega-3s May Be Why.

5 min readIf you're calculating protein intake targets for athletes in strength or hypertrophy phases:
Athletic Performance

Open Water Swimmers Are Not Drowning From Hypothermia — They're Dying From Cold Shock. Here's the Difference.

5 min readOutdoor Safety Risk Calculator
Athletic Performance

The Temperature at Which Athletic Performance Stops Declining and Starts Becoming Dangerous

5 min readIf you want to assess your outdoor training or race-day heat risk based on current conditions — integrating temperature, humidity, wind speed, and solar load into a single WBGT-based risk category:
Athletic Performance

The Athlete Who Is Always Tired Is Not Always Overtrained. The Distinction Determines the Treatment.

5 min readFor coaches monitoring standardised submaximal heart rate benchmarks across training blocks as an early-warning system for accumulating fatigue:
Athletic Performance

The Paleo Diet Argument Sounds Compelling Until You Look at What Paleolithic Athletes Actually Ate

5 min readIf you want to calculate your personalised paleo macro targets adjusted for training volume, body weight, and athletic goal — with food substitutions that maintain paleo principles while meeting athletic carbohydrate needs:
Strength & Muscle

Elite Sprinters Do a Heavy Back Squat Before Their Warm-Up Race. Most Coaches Think It's Counterproductive. The Science Calls It the Single Most Effective Neural Primer Available.

5 min readFor athletes calculating the 1RM strength baseline needed to generate meaningful PAPE — heavy enough that the conditioning set causes potentiation, not just fatigue:
Sports Nutrition

The Fitness Industry Sells Peri-Menopausal Women Cardio and Calorie Cuts. The Science Says They Need the Opposite.

5 min readBody Fat Calculator
Sports Nutrition

Creatine: The Complete Evidence Review — Dosing, Loading, Brain, Ageing, and Which Form Actually Works

16 min readCreatine Loading Calculator

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