[{"content":"Apex Run surfaces a lot of data. Here\u0026rsquo;s what the numbers actually mean.\nPerformance Metrics # VO2 Max — The maximum volume of oxygen your body can use per minute per kilogram of body weight (mL/kg/min). It\u0026rsquo;s the gold standard measure of aerobic fitness. Apex Run reads this from Apple Health, where it\u0026rsquo;s estimated by Apple Watch from your workout data. A rising VO2 Max over months of consistent training is a reliable sign of improving fitness.\nRunning Power — An estimate of the mechanical power output of your running, in watts. More consistent than pace on varied terrain.\nGAP (Grade Adjusted Pace) — Your pace adjusted to remove the effect of hills. Running uphill at 6:00/km takes roughly the same effort as running 5:00/km on flat ground. GAP normalizes this so you can compare efforts across hilly and flat courses. Apex Run shows a GAP chart in the run detail view.\nEfficiency Factor (EF) — A measure of how efficiently your cardiopulmonary system converts effort into forward motion.\nFormula: EF = GAP (m/s) ÷ Average Heart Rate (bpm)\nTo remove the effect of hills, EF uses Grade Adjusted Pace rather than raw pace. The result represents how many meters you travel per heartbeat. As fitness improves, you\u0026rsquo;ll run faster at the same heart rate — reflected as a gradual rise in EF over time.\nTypical range: 1.00 – 2.50 (higher = better aerobic efficiency) Long-term trend: A rising EF confirms aerobic development is working Watch out for: A significant EF drop at your usual effort may suggest fatigue, dehydration, or heat stress Because EF depends on your individual max HR and running form, it\u0026rsquo;s most useful as a personal trend — don\u0026rsquo;t compare your EF number to other runners.\nPace Stability Index (PSI) — Apex Run\u0026rsquo;s own metric measuring how consistently you hold your pace across a run. Stable rhythm generally means better energy distribution and lower risk of hitting the wall in long-distance races.\nFormula: PSI = (1 − GAP Standard Deviation ÷ GAP Average) × 100%\nPSI Interpretation \u0026gt; 90% Very steady rhythm, excellent energy distribution 85 – 90% Good rhythm, handles terrain changes well \u0026lt; 85% Large pace swings — try focusing on cadence to find steadier rhythm Note: In interval or fartlek workouts, drastic pace switching is the goal, so a low global PSI is expected and fine. Focus on segment performance instead.\nRunning Form Metrics # In modern training, pace and heart rate alone don\u0026rsquo;t tell the full story. Running form metrics — captured by Apple Watch\u0026rsquo;s motion sensors — quantify how your body moves, revealing technique, energy efficiency, and injury risk.\nThe core goals of monitoring these metrics:\nImprove Running Economy — run faster and further with less energy Prevent Injury — optimize landing mechanics to reduce impact forces Cadence — Total steps per minute (spm), counting both feet. Cadence is the cornerstone of running dynamics: increasing it is the most direct way to improve form, reduce knee and hip stress, and lower injury risk.\nTarget: 170 – 180 spm or above for most runners Low cadence often correlates with overstriding (foot landing too far in front of center of mass), which creates a braking effect and raises injury risk Stride Length — Distance covered between two consecutive ground contacts. Since Speed = Cadence × Stride Length, running faster requires increasing one or both.\nDon\u0026rsquo;t intentionally overstride. Reaching too far forward places your foot ahead of your center of mass, creating a braking force. An optimal stride length is the natural result of a powerful push-off combined with high cadence — let it extend naturally rather than forcing it.\nStride length is highly individual (correlated with height and pace), so there\u0026rsquo;s no single \u0026ldquo;best value.\u0026rdquo; Focus on maintaining cadence above 170 spm and let stride length take care of itself.\nGround Contact Time (GCT) — How long your foot stays on the ground per step, in milliseconds. Shorter GCT means a lighter, more elastic stride. Faster running naturally produces shorter GCT, but shorter is better at any pace.\nGCT Interpretation \u0026lt; 240 ms Excellent 240 – 270 ms Average \u0026gt; 270 ms Long — try increasing cadence Vertical Oscillation — How much your torso bounces up and down per step, in centimeters. Running is about moving forward, not upward. Excessive oscillation wastes energy and increases landing impact on the lower limbs.\nTarget: Below 10 cm Elite runners: Typically 6 – 8 cm Duty Factor — The percentage of a full gait cycle (one step per foot) that a single foot spends on the ground. It\u0026rsquo;s the boundary between running and walking: below 50% means there\u0026rsquo;s a flight phase (both feet off the ground) — that\u0026rsquo;s running. Above 50% means no flight phase — that\u0026rsquo;s walking.\nLower values indicate a longer flight phase and a more elastic, bouncy stride, usually reflecting better running economy.\nDuty Factor Level \u0026lt; 30% Elite 30 – 39% Advanced runner 40 – 50% Recreational / Jogger \u0026gt; 50% Race walking or hiking Vertical Ratio — Vertical oscillation divided by stride length, expressed as a percentage. A lower value means more energy is converted into horizontal displacement (forward motion) rather than vertical displacement (bounce). It\u0026rsquo;s one of the best single-number summaries of running economy.\nVertical Ratio Level \u0026lt; 6.0% Elite 6.0 – 8.0% Good / Advanced 8.1 – 10.0% Average \u0026gt; 10.0% Needs improvement — stride too short or bounce too high Training Load # Training Load — A rolling measure of how much stress your training is placing on your body, based on workout intensity and duration over recent weeks.\nACWR (Acute:Chronic Workload Ratio) — The core model Apex Run uses to evaluate whether your training is \u0026ldquo;healthy.\u0026rdquo;\nAcute Load (last 7 days) — represents current fatigue Chronic Load (last 28 days) — represents long-term fitness baseline Ratio = Acute ÷ Chronic ACWR Zone Meaning 0.8 – 1.3 🟢 Productive Sweet spot. Acute load slightly above chronic — stimulates adaptation while minimizing injury risk. Maintain current rhythm. 1.3 – 1.5 🟠 High Exertion Functional overreaching. A significant breakthrough attempt. Monitor closely; follow with a recovery week. \u0026gt; 1.5 🔴 Overreaching Danger zone. Weekly load increased too fast (\u0026gt;150% of long-term average). Rest or reduce load immediately. \u0026lt; 0.8 🔵 Recovery Recent load well below habitual level. Good after a major race, but long-term maintenance causes detraining. Current version calculates load based on distance. Short high-intensity runs (like intervals) may be slightly underestimated. Heart-rate-based load (TRIMP) is planned for a future version.\nTraining Load Trend — The direction your overall load is moving. Gradual increases of 10% or less per week are generally safe. Sharp spikes are what ACWR flags.\nSee also: Training Zones — heart rate zones and pace zones in detail · 80/20 Training Structure — how to balance your training load across intensity levels\n","externalUrl":null,"permalink":"/learn/glossary/","section":"Running Reference","summary":"","title":"Running Glossary","type":"learn"},{"content":" Heart Rate Zones # Heart rate zones divide your cardiovascular effort into bands, each producing different training adaptations. Apex Run uses 5 zones.\nSetting Your Zones # Zones are calculated as percentages of your maximum heart rate (max HR). Apex Run lets you set max HR two ways:\nFormula estimate — Enter your date of birth; Apex Run uses the standard formula (220 − age) as a starting point. Manual entry — If you\u0026rsquo;ve measured your max HR through a field test or know it from experience, enter it directly in Settings → Heart Rate Zones. The Five Zones # Zone % of Max HR Name What it develops Zone 1 50–60% Recovery Active recovery, blood flow without stress Zone 2 60–70% Easy / Aerobic Base Aerobic efficiency, fat metabolism, the foundation of endurance Zone 3 70–80% Tempo Lactate threshold — the highest pace you can sustain for ~1 hour Zone 4 80–90% Threshold VO2 Max development, race-specific fitness Zone 5 90–100% Maximum Neuromuscular power, anaerobic capacity Reading Zone Data in Apex Run # Run Detail — The heart zone section shows what percentage of a run you spent in each zone, as a horizontal bar. Insights — The Training Structure card on the Summary tab shows your recent zone distribution across all runs. Training Structure # Apex Run maps your zone distribution across recent runs to show whether your training follows the 80/20 rule — the pattern consistently found in elite endurance athletes. See the 80/20 Training Structure page for the full breakdown.\nThe Training Structure card in the Insights tab color-codes your effort distribution:\n🔵 Easy (Zone 1–2) — Target 75–80% of total training time 🟢 Moderate (Zone 3) — Target 10–15% 🔴 Hard (Zone 4–5) — Target 5–10% Pace Zones # Pace zones define training intensity by speed rather than heart rate. Based on Jack Daniels\u0026rsquo; running formula, each zone targets a specific physiological adaptation and corresponds to a specific training purpose.\nSetting Your Pace Zones # In Settings → Training Pace Zone, enter a recent race result (distance and finish time). Apex Run derives your five training paces from this using standard formulas.\nThe Five Pace Zones # E — Easy Pace\nUsed for the majority of your training. Builds aerobic base and promotes recovery between hard sessions. You should be able to hold a conversation at this effort. Most of your weekly mileage — long runs, warm-ups, cool-downs — should be at Easy pace.\nM — Marathon Pace\nYour goal marathon race pace. Used for marathon-specific tempo runs and race simulation workouts. Bridges Easy and Threshold — specific enough to build race fitness, steady enough to accumulate significant volume.\nT — Threshold Pace\nComfortably hard — the fastest pace you can sustain for roughly 60 minutes. Improves your lactate clearance capacity and endurance sustainability. Used in tempo runs (20–40 min continuous) and cruise intervals (shorter reps with brief recoveries).\nI — Interval Pace\nApproximately your 5K race effort. Targets VO2 Max directly — the ceiling of your aerobic system. Used in track-style intervals (800m–1200m repeats) with adequate recovery between reps. Demanding: limit this work to once a week.\nR — Repetition Pace\nFaster than interval pace — 1500m to mile race effort or quicker. Improves running economy and neuromuscular coordination (speed skill). Used in short, fast repeats (200m–400m) with full recovery. The goal is quality mechanics, not cardiovascular load.\nThe Grey Zones: What to Avoid # Between each named zone are gaps — paces that don\u0026rsquo;t target any specific adaptation efficiently. Training in these gaps is common but ineffective: you accumulate fatigue without getting the full benefit of either adjacent zone.\nGrey Zone Between Why to Avoid Easy–Marathon E and M Tiring without the aerobic base benefit of Easy or the race-specific stimulus of Marathon pace. Slow down to Easy. Marathon–Threshold M and T Too slow for lactate threshold training, too fast for marathon-specific benefits. Clarify the session purpose. Threshold–Interval T and I High fatigue accumulation with vague benefits — neither reaching VO2 Max nor efficiently clearing lactate. Stick to defined zones. Interval–Repetition I and R Lacks the speed for neuromuscular adaptation, but form tends to break down and lactate accumulates. High injury risk. The Pace Zone Distribution chart in Run Detail helps you see exactly where your effort landed. If you find yourself consistently in the grey zones, adjust your training plan to hit the intended targets cleanly.\nSee also: 80/20 Training Structure — how to balance time across zones · Running Glossary — definitions for GAP, EF, ACWR, and other metrics\n","externalUrl":null,"permalink":"/learn/training-zones/","section":"Running Reference","summary":"","title":"Training Zones","type":"learn"},{"content":"The most counterintuitive truth in endurance training: running slower makes you faster.\nDecades of research on elite endurance athletes — from Olympic marathoners to world-class triathletes — consistently shows the same pattern. The best performers spend roughly 80% of their training at low intensity and only 20% at moderate-to-high intensity. This is called polarized training, or the 80/20 rule.\nWhy Low Intensity Dominates # Running easy feels unproductive. The pace is comfortable, your breathing is relaxed, and it doesn\u0026rsquo;t feel like \u0026ldquo;real\u0026rdquo; training. But this is where the aerobic engine is built:\nCapillary density — More blood vessels grow around muscle fibers, improving oxygen delivery. Mitochondrial density — More energy-producing structures per cell, increasing fat oxidation capacity. Cardiac efficiency — Your heart pumps more blood per beat (stroke volume) at lower effort. Recovery — Low-intensity running promotes blood flow without adding meaningful stress to the system. These adaptations accumulate slowly — over months, not weeks. They\u0026rsquo;re the foundation that all other training sits on. Hard sessions only work if the base is there.\nThe Black Hole: The Most Common Mistake # Most recreational runners fall into what sports scientists call the \u0026ldquo;black hole\u0026rdquo; — spending most of their time at moderate intensity. This means:\nToo fast for aerobic base development and recovery Too slow for genuine high-intensity adaptations (VO2 Max, lactate threshold) The result: chronic fatigue, slow progress, and a frustrating plateau. It feels like you\u0026rsquo;re working hard. You are. You\u0026rsquo;re just not adapting efficiently.\nIf you can\u0026rsquo;t hold a conversation on your \u0026ldquo;easy\u0026rdquo; run, you\u0026rsquo;re probably in the black hole. Slow down.\nThe Three Training Areas # Apex Run maps your heart rate into three physiological areas to make the 80/20 picture immediately visible:\n🔵 Easy — Zone 1–2 (60–75% max HR)\nThe bulk of your training. You can speak in full sentences. At this effort, fat is the primary fuel source and recovery is possible even while running. Most runners should be here for at least 75–80% of their total weekly training time.\nIf this feels embarrassingly slow at first, that\u0026rsquo;s normal. Your easy pace will naturally get faster as your aerobic base improves — without any increase in effort.\n🟢 Moderate — Zone 3 (75–85% max HR)\nTempo and marathon pace effort. Breathing deepens and conversation becomes labored. This zone has a place in training — but a small one (10–15%). It\u0026rsquo;s demanding enough to limit recovery while not providing the specific high-intensity stimulus of true hard work.\nUsed intentionally: marathon-pace long runs, threshold tempo runs.\n🔴 Hard — Zone 4–5 (85–100% max HR)\nIntervals, track work, race efforts. Breathing is rapid and conversation is impossible. This is where VO2 Max and speed are built — but only 5–10% of total training should live here. More than this and recovery is compromised, reducing the quality of every other session.\nHow to Check Your Distribution in Apex Run # The Training Structure card in the Insights tab shows your zone distribution across recent runs as a color-coded bar. Green means your distribution is close to the 80/20 ideal. If your chart is heavy on blue-green (moderate zone), the fix is straightforward: slow down your easy runs.\nIf you have too little Easy (🔵):\nSet a heart rate ceiling for easy runs — stop or walk if you exceed it. Ignore pace entirely on easy days. Let heart rate govern speed. Accept that easy days feel genuinely easy. That\u0026rsquo;s the point. If you have too little Hard (🔴):\nAdd one dedicated interval or tempo session per week. Keep it short and sharp — quality over quantity. Make sure recovery between hard sessions is adequate (48–72 hours minimum). The Long Game # The 80/20 pattern requires patience. To understand how Apex Run defines the individual heart rate zones and training pace zones, see Training Zones.\nIn the short term, running more easy miles feels like going backwards. Over a season of consistent training, it produces a higher aerobic ceiling — which raises the pace at which you can sustain every other zone.\nElite athletes didn\u0026rsquo;t arrive at 80/20 because they lacked ambition. They use it because it works. The goal is to accumulate as much aerobic stress as possible while staying recovered enough to absorb it.\n","externalUrl":null,"permalink":"/learn/training-structure/","section":"Running Reference","summary":"","title":"80/20 Training Structure","type":"learn"},{"content":" What Is Pace? # Pace is how long it takes you to run one unit of distance. It\u0026rsquo;s the inverse of speed.\nSpeed asks: how far can I go in one minute? (e.g., 200 meters/minute) Pace asks: how long does it take me to cover one unit? (e.g., 5:00 per kilometer) Runners use pace rather than speed because it\u0026rsquo;s more intuitive for planning: you know roughly how long a race will take because you know your target pace per km (or per mile).\nPace Formats # Apex Run displays pace in minutes:seconds per kilometer (min/km) or minutes:seconds per mile (min/mi), depending on your Distance Unit setting (Settings → General → Distance Unit).\nA pace of 5:30/km means it takes 5 minutes and 30 seconds to run one kilometer.\nQuick Reference # Pace (min/km) Pace (min/mi) Approx. 5K time 4:00 6:26 20:00 4:30 7:14 22:30 5:00 8:03 25:00 5:30 8:51 27:30 6:00 9:39 30:00 6:30 10:28 32:30 7:00 11:16 35:00 The Pace Relationship # Any run can be described by three values. Know any two and you can calculate the third:\nPace = Time ÷ Distance Time = Pace × Distance Distance = Time ÷ Pace Example: You want to run a 10K in 50 minutes. What pace do you need? Pace = 50 min ÷ 10 km = 5:00/km\nExample: You ran for 45 minutes at 5:30/km. How far did you go? Distance = 45 min ÷ 5.5 min/km = 8.18 km\nUsing the Pace Calculator in Apex Run # The Pace Calculator lives in the Profile tab under Runner\u0026rsquo;s Toolkit. Enter any two of the three values (Distance, Time, Pace) and the third is automatically calculated and highlighted.\nThis is useful for:\nPlanning a race: \u0026ldquo;I want to finish in X time — what pace is that?\u0026rdquo; Pacing a long run: \u0026ldquo;My long run is Y km — at easy pace, how long will I be out?\u0026rdquo; Analyzing a workout: \u0026ldquo;I covered Z km in W minutes — what was my average pace?\u0026rdquo; Average Pace vs. Instant Pace # Average pace — Total time divided by total distance for the whole run. This is what Apex Run shows in the main metrics section.\nInstant pace — Your pace at any specific moment. Shown in the pace chart, where you can tap to inspect individual points. Instant pace fluctuates with hills, traffic stops, and natural speed variation.\nSplit pace — Average pace for a defined portion of the run (e.g., each kilometer). Shown in the splits section, useful for evaluating pacing strategy.\n","externalUrl":null,"permalink":"/learn/pace-guide/","section":"Running Reference","summary":"","title":"Pace Guide","type":"learn"},{"content":" Why Use a Running Pace Calculator? # Whether you\u0026rsquo;re training for your first 5K or aiming for a personal best in the marathon, knowing your running pace is essential. A pace calculator takes the guesswork out of your race strategy by instantly determining:\nYour Target Pace: If you have a specific finish time in mind, calculate exactly how fast you need to run each kilometre or mile. Your Finish Time: Wondering what your finishing time will be if you run a 5:30 min/km pace? Our tool estimates your total time instantly. Your Distance: If you ran for 45 minutes at a steady pace, find out exactly how far you travelled. How to Calculate Running Pace # Your running pace is the average amount of time it takes to cover a specific distance (usually a mile or a kilometre). The mathematical formula is simple:\nPace = Time ÷ Distance\nFor example, if it takes you 50 minutes to run 10 kilometres, your pace is 50 ÷ 10 = 5:00 min/km. Our calculator handles all the complicated conversions between hours, minutes, and seconds so you can focus entirely on your training plan.\nPlanning for Popular Race Distances # Understanding how your pace scales across different distances is crucial for avoiding burnout on race day. Use the Estimated Finish Times table above to see how a consistent pace translates to standard distances:\n5K (5 kilometres / 3.1 miles): A fast, high-intensity distance. Often used as a benchmark for your aerobic capacity. 10K (10 kilometres / 6.2 miles): Requires a balance of speed and endurance. Your 10K pace is typically slightly slower than your 5K pace. Half Marathon (21.1 kilometres / 13.1 miles): An endurance event where pacing strategy becomes critical to avoid \u0026ldquo;hitting the wall.\u0026rdquo; Marathon (42.2 kilometres / 26.2 miles): The ultimate test of aerobic endurance. Even a 5-second difference per kilometre can heavily impact your final finish time. By regularly tuning your target pace based on your recent training runs, you can set realistic, achievable goals for your upcoming races.\nFrequently Asked Pacing Questions # Q: How fast do I need to run a 25-minute 5K?\nTo run a sub-25 minute 5K, you need to maintain an average pace of 5:00 min/km (or about 8:03 min/mile).\nQ: What pace is a sub-4 hour marathon?\nBreaking the 4-hour marathon barrier requires an average pacing of 5:41 min/km (or 9:09 min/mile) for the entire 42.2 kilometres. It\u0026rsquo;s often recommended to train at a slightly faster pace to account for water station slowdowns.\nQ: How fast do I need to run a 50-minute 10K?\nYou will need to run exactly 5:00 min/km (or 8:03 min/mile) to hit 50 minutes flat.\nQ: What pace do I need for a 2-hour half marathon?\nTo break the 2-hour mark in a half marathon (21.1 km), you need to maintain an average pace of 5:41 min/km (or 9:09 min/mile). Fun fact: this is the exact same pace required for a sub-4 hour full marathon!\nQ: What is a \u0026ldquo;good\u0026rdquo; running pace for a beginner?\nFor a beginner, a conversational pace (where you can speak full sentences without gasping) is ideal. This typically falls anywhere between 6:00 to 7:30 min/km (9:30 to 12:00 min/mile), but this varies greatly based on age, fitness level, and terrain. Always prioritize consistency over speed when starting out!\nQ: Is there a smarter way to predict my race times than doing the math?\nAbsolutely! While a simple pace calculator is great for basic math, a real race prediction requires analyzing your personal training history. The Apex Run app includes a built-in Race Predictor feature that automatically evaluates your past runs, current fitness level, and recovery metrics to forecast your finish times for 5Ks, 10Ks, half marathons, and full marathons—without you calculating a thing!\n","externalUrl":null,"permalink":"/learn/pace-calculator/","section":"Running Reference","summary":"","title":"Pace Calculator","type":"learn"},{"content":"If you\u0026rsquo;ve ever stood at a starting line wondering what pace you should hold, you know the anxiety of race pacing. Will you start too fast and hit the wall, or start too slow and miss your goal?\nThe Apex Run Race Predictor removes this guesswork entirely. By automatically analyzing your real-world running data, it forecasts your exact finish times for everything from a 5K to a full Marathon.\nHow Does it Work? Riegel\u0026rsquo;s Formula # At its core, the predictor is powered by Riegel\u0026rsquo;s Formula, a mathematically proven method developed by researcher Peter Riegel in 1977 to predict race times across different endurance distances.\nThe formula is elegantly simple:\nT2 = T1 × (D2 / D1)^1.06\nWhere:\nT1 is your known time for a baseline run (e.g., your fastest recent 10K). D1 is the distance of that baseline run. D2 is the distance of your upcoming race (e.g., a Marathon). T2 is your predicted finish time for the new race. The exponent 1.06 accounts for the natural fatigue curve—you mathematically lose a predictable amount of speed as a race gets longer.\nThe Magic: Using Your Last 6 Weeks # The biggest problem with manual pace calculators is choosing the right \u0026ldquo;baseline\u0026rdquo; run (T1). If you choose a personal best from a year ago when you were fitter, your marathon prediction will be dangerously fast. If you choose an easy jog, it will be far too slow.\nInstead of asking you to input arbitrary PRs, Apex Run automatically scans your last 6 weeks of training. It mathematically identifies your most representative efforts—filtering out easy recovery jogs and interval rests—and naturally calibrates Riegel\u0026rsquo;s Formula to your exact, current fitness level.\nBecause your fitness changes constantly, your predicted finish times organically update every time you log a run.\nUnderstanding Your Prediction # Why is the prediction sometimes slower than my all-time PB?\n“PB represents your peak, prediction reflects your current state.”\nYour fitness naturally fluctuates with your training loops—moving through Base, Peak, and Recovery cycles. Because Apex focuses on your most recent training performance, a prediction might appear slower than your all-time best if you are currently doing mostly easy runs or are in a recovery block.\nThis is completely normal! As you incorporate more high-intensity workouts and approach your peak phase, the prediction will trend back upwards to match your race-day readiness.\nCheck your Race Predictor in Apex Run today to see what you are currently capable of!\n","externalUrl":null,"permalink":"/learn/race-predictor/","section":"Running Reference","summary":"","title":"Race Predictor","type":"learn"},{"content":"Today was scheduled for a long slow distance (LSD) run. The goal was simple: get the distance in while keeping the intensity strictly within the aerobic development zone (Zone 2). I ended up with exactly 21.21km — a very satisfying and memorable number on the watch.\nFighting the Summer Heat and Cardiac Drift # Starting early is the only way to survive July running, but even then, the sun rises fast and the humidity is relentless. Here is how the run unfolded:\nFirst 10km: Felt fantastic and locked in. Heart rate stayed beautifully within my target Zone 2 range (around 135–142 bpm), and the rhythm was smooth. After 10km: The temperature rose quickly. This is where cardiac drift kicked in — the heart has to work harder to pump blood to the skin for cooling, causing the heart rate to climb even if the speed doesn\u0026rsquo;t change. The Adjustment: To prevent my heart rate from spiking into Zone 3 and beyond, I had to dial back my pace significantly. It took some discipline to slow down and embrace a slower stride, but keeping the stress on the aerobic system (rather than muscle fatigue) is what summer base building is all about. A tough but rewarding morning. Paces might be slower in the summer, but the heart doesn\u0026rsquo;t lie — the effort was there, and these hot miles will pay off when autumn arrives.\n","date":"18 July 2026","externalUrl":null,"permalink":"/log/aerobic-base-july/","section":"Running Log","summary":"A half-marathon LSD (21.21km) with a very interesting number, fighting summer heart rate drift, and dialing back the pace to stay in Zone 2.","title":"21.21km: Summer LSD under the Heat","type":"log"},{"content":"","date":"18 July 2026","externalUrl":null,"permalink":"/","section":"Apex Run","summary":"","title":"Apex Run","type":"page"},{"content":"","date":"18 July 2026","externalUrl":null,"permalink":"/log/","section":"Running Log","summary":"","title":"Running Log","type":"log"},{"content":"","date":"5 June 2026","externalUrl":null,"permalink":"/diary/","section":"Dev Diary","summary":"","title":"Dev Diary","type":"diary"},{"content":"The Maffetone Method has one central claim: train at the right heart rate consistently, and your easy pace will quietly get faster over months. You don\u0026rsquo;t chase speed. You let the aerobic base build, and speed comes as a side effect.\nI wasn\u0026rsquo;t doing formal MAF training. But reading about it left a question I couldn\u0026rsquo;t shake: I already have heart rate data for every run. Could I see this same signal in my own numbers, from a different angle?\nA different angle on the same idea # The Zone 2 Average Pace is simple: the time-weighted average pace during the minutes of a run where your heart rate was in Zone 2 — between 73 and 80 percent of max, by default. It\u0026rsquo;s not a strict MAF pace. You\u0026rsquo;d need a dedicated test protocol for that. But it\u0026rsquo;s watching the same thing: what does your aerobic effort actually cost you, in terms of pace, right now?\nThe number lives at the bottom of the Heart Rate Zones card on each run.\nSix months of easy runs # When I looked at the trend, my Zone 2 pace was faster than it was six months ago. Not dramatically — but measurably. The aerobic work had added up quietly, in the background, across runs I hadn\u0026rsquo;t thought of as training.\nThat\u0026rsquo;s the thing about slow running. You don\u0026rsquo;t feel it happening. You just eventually notice it did.\n","date":"5 June 2026","externalUrl":null,"permalink":"/diary/zone2-pace/","section":"Dev Diary","summary":"MAF training theory says run slow enough and your easy pace gets faster. I already had the heart rate data. I just needed to look at it differently.","title":"Running slower, getting faster","type":"diary"},{"content":"I crossed a half marathon finish line. The chip time logged automatically. Heart rate, cadence, splits — all there.\nSomewhere in my camera roll: the finish arch, a sweaty post-race selfie, the medal my kid insisted on holding.\nTwo different places. The race lived in both, or neither.\nRaces aren\u0026rsquo;t just longer runs. They have a morning, a crowd, a finish line you\u0026rsquo;ve been thinking about for months. The data captures what happened — the photos are what it felt like.\nTrophy Room is where those two things finally live together. The cover photo sits right in the run — the first thing you see when you open it. The gallery of race-day shots below. The GPS trace and the medal photo, side by side, like they should be.\nAnd somewhere in your profile: a grid of every race you\u0026rsquo;ve ever run. Not a list of distances and times — a wall of memories. The ones you trained for. The ones that hurt. The ones you\u0026rsquo;d run again tomorrow.\n","date":"28 May 2026","externalUrl":null,"permalink":"/diary/trophy-room/","section":"Dev Diary","summary":"After crossing a half marathon finish line, the chip time logged automatically, the GPS trace was perfect — and the finisher photo was somewhere else entirely. Trophy Room puts them back together.","title":"The photos were on my phone. The run was in the app.","type":"diary"},{"content":"Race reports have always shown 5km splits. I\u0026rsquo;ve been reading them for years without thinking twice about it.\nThen after my last half marathon, I looked at the splits section and thought — wait, why don\u0026rsquo;t we have this in Apex Run?\nSo now we do. Any run over 10km gets a 5K Splits view — automatically grouped into 5-kilometer blocks. Pace, heart rate, split time. The average pace line sits in the middle; orange blocks were faster, blue were slower.\nSame format race reports have used forever. Turns out it works just as well for a Sunday long run.\n","date":"12 May 2026","externalUrl":null,"permalink":"/diary/5k-splits/","section":"Dev Diary","summary":"Race reports have always shown 5km splits. I’ve been reading them for years without thinking twice about it — until after my last half marathon, when I finally thought: why don’t we have this in Apex Run?","title":"Stolen from the race report","type":"diary"},{"content":"Numbers look the same. A 10km on Tuesday and a 10km on Thursday — same distance, similar pace, identical in a list. But they were completely different runs. Different neighborhoods, different shapes, different feelings.\nSwitch to gallery mode and you see them as they actually were.\nEach card shows the GPS route of that run — just the line, no map background, clean against white. Distance, average heart rate, and stride length sit below. The date is in the corner.\nScroll through a month and you get a visual diary. The big loop on the 19th. The out-and-back on the 22nd. The track session that drew a perfect oval. You recognize your runs the way you remember them — by where you went.\nBuilt for outdoor runners who explore. If every run is the same route, the list view is fine. If your runs look different because your runs are different, this one\u0026rsquo;s for you.\n","date":"27 April 2026","externalUrl":null,"permalink":"/diary/run-grid/","section":"Dev Diary","summary":"Numbers can’t tell you which run was the hilly loop, the long out-and-back, or the lazy lap around the lake. Your GPS route can. Gallery mode shows your run list as a stream of route maps — one glance and you know exactly which run was which.","title":"Your runs, drawn","type":"diary"},{"content":"Same friend.\nAfter the interval share template shipped, he started using Running Facts for his easy runs — sent me a screenshot a few weeks later, said it was exactly what he wanted. Then last month, another message. This time it was an outdoor interval.\nThe share card showed average pace. No work pace. No rest pace. Heart rate collapsed into a single number. Work time hidden inside total duration. \u0026ldquo;This could be any run,\u0026rdquo; he said.\nHe was right again.\nTwo states, one average # Running Facts assumes a single-state run. One pace, one heart rate, everything averaging cleanly across the whole distance. For an easy 8km, that works fine.\nAn interval run is always two things alternating: effort and recovery. Collapsing that into one average pace turns 4'58\u0026rsquo;\u0026rsquo; work and 7'27\u0026rsquo;\u0026rsquo; rest into something in the middle that describes neither. Same problem with heart rate, same problem with time.\nWhat the card shows now # The outdoor interval template keeps the bar chart at the top — same visual language as before, orange work bars and gray rest bars, the pattern of the session at a glance. Below it, a two-column table: left side is work, right side is rest. Work Pace next to Rest Pace. Work HR next to Rest HR. Work Time next to total Duration. The layout is the workout.\nNow when he shares an interval, it looks like one.\n","date":"25 April 2026","externalUrl":null,"permalink":"/diary/outdoor-interval-share-template/","section":"Dev Diary","summary":"Same friend. He liked Running Facts for his easy runs. Then he finished an outdoor interval and sent me another screenshot — average pace, no work pace, no rest pace, nothing split. So I built an interval edition.","title":"The facts it couldn't show","type":"diary"},{"content":"I was hiking up a hill with my watch recording it as a hike. Somewhere near the top I started running — just felt like it — and never bothered switching the activity type. Finished the whole descent as a run, saved it as a hike.\nApex Run only focuses on running. It doesn\u0026rsquo;t pull in hiking or walking data automatically. That run just didn\u0026rsquo;t exist in my log.\nThe fix # There\u0026rsquo;s now an import option that lets you bring in a hiking or walking workout from the last 180 days and treat it as a run. It\u0026rsquo;s a one-time correction for workouts that ended up under the wrong type.\nThe imported run is marked with its source — \u0026ldquo;HealthKit (Hiking)\u0026rdquo; or \u0026ldquo;HealthKit (Walking)\u0026rdquo; — so you always know where it came from. It gets set to Easy run type since mixed-activity workouts don\u0026rsquo;t fit neatly into anything harder. And because hiking and walking data typically doesn\u0026rsquo;t carry cadence, stride, or ground contact time, the running dynamics card stays hidden for these runs — no point showing a blank.\nNothing is written back to HealthKit. Your original workout stays exactly as it was.\nIt won\u0026rsquo;t happen often. But when it does, at least the run counts.\n","date":"13 April 2026","externalUrl":null,"permalink":"/diary/import-hiking-as-run/","section":"Dev Diary","summary":"I climbed a hill recorded as a hiking workout, then broke into a run without switching the activity type. Apex Run only tracks runs — so that effort just disappeared. This feature exists because of that day.","title":"I started hiking. Then I started running.","type":"diary"},{"content":"After a long run, I\u0026rsquo;d open the splits view and stare at 20-something pace numbers, trying to remember the average so I could mentally sort which were fast and which were slow. It\u0026rsquo;s a small friction, but it adds up every single time.\nOne day it clicked: just draw the line.\nA dashed vertical line now sits at your average pace. Each split bar is colored by which side it falls on — orange if you were faster than average, blue if you were slower. No numbers to compare. No mental math. The whole run\u0026rsquo;s rhythm is right there.\nEspecially useful for long runs, where the pacing story tends to get interesting after km 10 or 15. A string of blue bars late in the run tells you something. So does a cluster of orange ones early.\n","date":"10 April 2026","externalUrl":null,"permalink":"/diary/splits-avg-line/","section":"Dev Diary","summary":"After a long run, scrolling through 20+ splits and mentally comparing each pace to the average is tedious. So I drew a line. Orange bars are faster than average. Blue bars are slower. Now you see the whole run’s rhythm instantly.","title":"Fast or slow, at a glance","type":"diary"},{"content":"New share template just dropped: the elevation profile runs across the top of the card as a filled curve, colored by heart rate zone as you moved through the run.\nBlue where you were easy. Green through aerobic effort. Yellow as it pushed toward threshold.\nIf you run outdoors with any real undulation — rolling hills, a long climb, a trail with constant ups and downs — this one\u0026rsquo;s for you. The shape of the curve shows the terrain. The color shows how your body responded to it. The whole story of the run in a single glance.\n","date":"5 April 2026","externalUrl":null,"permalink":"/diary/elevation-hr-share-template/","section":"Dev Diary","summary":"A share card that draws your elevation profile as a curve — then colors it by heart rate zone. The shape tells you where the terrain went. The color tells you how hard your body worked to get there.","title":"One line, two stories","type":"diary"},{"content":"For a while, every time I wanted to run at 180 spm I\u0026rsquo;d go find an MP3. A metronome track, a playlist with the right BPM, anything I could use to keep my feet honest. It worked, but searching for a new one every time felt like a solved problem I kept re-solving.\nOne day in the middle of that search, the thought landed: why isn\u0026rsquo;t this just in the app?\nA metronome, not a music player # Apex Run\u0026rsquo;s Cadence Metronome is a synthesized audio click — nothing fancy, just a clean tone that fires at the exact rate you set. BPM range is 100–220, defaulting to 170. The controls are deliberately simple: a large BPM number, ±1 buttons, a slider. Set it and run.\nWhat mattered most was getting the audio right. The metronome plays in the background with the screen locked, and it mixes with whatever you\u0026rsquo;re already listening to — music, podcasts, nothing — without interrupting it. The beat scheduling runs against the audio hardware clock, so timing stays accurate even when the app isn\u0026rsquo;t in the foreground.\nIt\u0026rsquo;s a free feature. No Pro gating. A metronome should just work.\nOn the lock screen too # In v1.5, a dedicated widget brings the metronome to the home screen and lock screen — current BPM target, start/stop control, no need to open the app. Set your cadence once, start it from your lock screen, go.\nThe MP3 folder on my phone is a lot less crowded now.\n","date":"1 April 2026","externalUrl":null,"permalink":"/diary/cadence-metronome/","section":"Dev Diary","summary":"Every time I wanted to run at 180 spm, I’d go find an MP3. One day in the middle of that search, the thought landed: why isn’t this just in the app?","title":"Stop searching for the beat","type":"diary"},{"content":"Nutrition facts exist because someone decided that what goes into your food deserves a complete, standardized breakdown — not just the headline number.\nRunning data felt the same way to me. A share card with distance and pace is fine. But there\u0026rsquo;s so much more in a single run: calories, elevation, heart rate, cadence, stride, power, intensity. Most of it never makes it to the share.\nThe format that already worked # The nutrition facts label is one of the most legible information displays ever designed. Dense but scannable. Every number has a label. The hierarchy is clear. It doesn\u0026rsquo;t feel cluttered because the format is familiar — you know how to read it before you even start.\nSo I borrowed it.\nThe Running Facts share template lays out your run metrics in the same table format: rows of labels and values, clean black lines on white, nothing omitted. Pace, duration, calories, elevation, average and max heart rate, cadence, stride, power, intensity — all of it in one card. A small heart rate chart sits at the top for the shape of the run; the rest is just the facts.\nFor the data runners # Not everyone wants this much on a share. But for the runner who cares about cadence and power and wants to send something that shows the full picture — this is the template. Every number, nothing hidden.\nNutrition facts don\u0026rsquo;t summarize. They list. That\u0026rsquo;s the idea.\n","date":"25 March 2026","externalUrl":null,"permalink":"/diary/running-facts/","section":"Dev Diary","summary":"Nutrition facts exist because what goes into your food deserves a complete breakdown. Running data felt the same way — so I borrowed the format.","title":"Nutrition facts, but for your run","type":"diary"},{"content":"The first version of Best Effort was just numbers. Open a run, scroll to the Best Effort card, see your fastest 1K, 5K, 10K, half marathon times. Clean and correct.\nEvery time I looked at it, I wanted to tap it. Not because anything was wrong — but because a time like 24:20 always made me wonder: where on the route did that happen? Was it the flat stretch near the start, or did I somehow run my fastest 5K in the back half?\nSo I built the answer.\nWhere did that happen? # Tap any best effort and it opens the full map with the segment pinned directly on the route. Numbered markers show where each effort started and ended, the route highlights the exact stretch, and the pace chart below lights up the same window. Switch between distances using the pill selector at the bottom and the map updates in place.\nThe number was always right. Now you can see where it came from.\n","date":"15 March 2026","externalUrl":null,"permalink":"/diary/best-effort/","section":"Dev Diary","summary":"The first version of Best Effort was just numbers. Every time I looked at it, I wanted to tap it — to see where on the route that fastest split actually happened.","title":"The number that made me want to tap","type":"diary"},{"content":"A few days ago, my friend sent me a screenshot of his interval run share. Standard card — total distance, duration, average pace. He followed it up with a message: \u0026ldquo;this tells me nothing.\u0026rdquo;\nHe was right. He\u0026rsquo;d just done 7 × 1km repeats. The share card made it look like a slow jog.\nThe problem with a single number # An interval run isn\u0026rsquo;t one thing. It\u0026rsquo;s a structure — alternating effort and recovery, repeated. The whole point is the pattern: how fast were the work intervals, how consistent were they, how much rest in between. A single average pace flattens all of that into noise.\nFor a 10km easy run, average pace is a fine summary. For intervals, it\u0026rsquo;s nearly useless.\nWhat the template shows # The interval share template centers on a bar chart. Orange bars are work intervals; gray bars are rest. Bar height encodes pace — taller means faster. A few key pace labels float above standout bars so you can read the numbers without it getting cluttered.\nBelow the chart, three stats: total intervals, fastest pace, and total time at high intensity. Together they give you the shape of the workout at a glance — how many reps, how fast at peak, how much hard effort in total.\nFor the friend who complained # He does intervals every week. Now when he shares, you can see the alternating pattern, spot the rep where he pushed hardest, and tell immediately that this wasn\u0026rsquo;t a jog — it was a workout.\nThat\u0026rsquo;s all a share card needs to do.\n","date":"2 March 2026","externalUrl":null,"permalink":"/diary/interval-share-template/","section":"Dev Diary","summary":"A friend complained that sharing his interval run looked identical to any easy jog. He was right. So I built a share template that actually shows the structure of an interval workout — work bars, rest bars, and the numbers that matter.","title":"A share card that actually shows the workout","type":"diary"},{"content":"Opening an app just to check a number you already half-know is a small friction, but it adds up. Did I hit my distance goal this week? How far was yesterday\u0026rsquo;s run? These are one-second questions that shouldn\u0026rsquo;t require a four-tap answer.\nApex Run has two home screen widgets for exactly this.\nLatest Run # A glance at your most recent run — distance, pace, duration, date — without unlocking anything beyond your home screen. Available in small and medium sizes. Small gives you the headline numbers; medium adds a bit more detail.\nUseful for the morning after a run, when you want to remember what you actually did before the day wipes it.\nWeekly Stats # The stats widget shows your key training numbers for the current week, alongside a sparkline — a small trend curve of a metric(can be configured in widget settings). At a glance you can see not just where you are this week, but whether you\u0026rsquo;re trending up, holding steady, or backing off.\nTap the widget and it opens directly to the Stats View inside the app for the full breakdown.\nAlso available in small and medium sizes.\nWhy widgets work for running # Running is a habit measured in weeks and months. The home screen is something you look at dozens of times a day. Putting your training data there — passively, without any action required — means you\u0026rsquo;re always loosely aware of where you are in your week. That awareness, low-effort as it is, has a way of keeping you honest.\n","date":"8 February 2026","externalUrl":null,"permalink":"/diary/widgets/","section":"Dev Diary","summary":"Two widgets that put your running data on the home screen — a latest run glance and a weekly stats summary with a trend sparkline. No app launch required.","title":"Your training, on the home screen","type":"diary"},{"content":"Some runners finish a workout, glance at average pace, and move on. That\u0026rsquo;s completely fine.\nAnd then there are the others — the ones who want to know exactly what happened at kilometer 4, what their heart rate was doing in the back half, whether their cadence held up on the climb. For those runners, Apex Run has a split detail view that doesn\u0026rsquo;t hold back.\nEverything, per split # Tap any split in your run and you get a dedicated screen for that segment. The metrics section covers the full picture:\nTiming \u0026amp; Distance — start time and end time (relative to your run start), duration, split distance, and cumulative distance to the end of that split.\nPace — average pace, grade-adjusted pace (GAP) if GPS data is available, and max pace within the split.\nHeart Rate — average and max BPM, plus average and max intensity as a percentage of your max HR.\nForm — step count, average cadence, and average stride length.\nElevation — total ascent and descent for that split.\nFor Pro users, two additional metrics appear: Pace Stability Index and Running Efficiency.\nEverything is calculated from the raw sensor data within that split\u0026rsquo;s window — not interpolated from the whole run.\nHeart rate zones and charts # Below the metrics, a heart rate zones breakdown shows how your time in that split was distributed across zones — a segmented color bar with a per-zone legend showing percentage and duration.\nFor splits longer than one minute, three charts appear: pace over time (with elevation overlay), heart rate over time (with elevation overlay), and an elevation profile. Each one zoomed to just that split, so the detail actually shows.\nWho it\u0026rsquo;s for # Not everyone wants this much. For casual review, the standard split table is enough.\nBut if you\u0026rsquo;re the kind of runner who wonders why kilometer 7 felt different from kilometer 6 — and wants actual numbers to look at — this view exists for you.\n","date":"5 February 2026","externalUrl":null,"permalink":"/diary/detailed-splits/","section":"Dev Diary","summary":"Some runners just want the numbers. All of them. Apex Run’s split detail view calculates every metric for each individual split — pace, heart rate zones, cadence, elevation, and more — for the data lovers in the room.","title":"Splits, all the way down","type":"diary"},{"content":"VO2 max is the number most coaches point to when they want a single measure of aerobic fitness. It predicts race performance better than any individual workout metric. It responds to training over weeks and months in a way that tells you whether what you\u0026rsquo;re doing is actually working.\nAnd in Apple Health, it\u0026rsquo;s buried three taps deep, detached from any run, sitting in a list of samples with timestamps and no context.\nThe data exists. It just isn\u0026rsquo;t where it should be.\nHow Apple calculates it — and why the connection is lost # Apple Watch estimates VO2 max using heart rate response during outdoor runs. After you finish a run, the watch processes the data and, if conditions were right, writes a new VO2 max sample to HealthKit. That sample carries a timestamp, a value, and nothing else — no link back to the workout that produced it.\nSo even though the reading appears within minutes of your run finishing, it carries no reference back to the workout that produced it. Just a timestamp and a number.\nApex Run closes that gap. When a VO2 max sample appears in HealthKit within a few minutes of a run ending, the app associates that reading with the run. Open the run detail, and your VO2 max for that day is right there — alongside pace, heart rate, and everything else from that workout.\nWhat you can do with it # A single VO2 max reading isn\u0026rsquo;t very interesting. A series of them, attached to real runs, starts to tell a story.\nYou can see whether your aerobic fitness tracked upward during a consistent training block, or held flat during a recovery week. You can notice that your VO2 max estimate tends to come in higher on your harder efforts, or that it dropped slightly after a period of fatigue. It becomes part of the record of your training — not an isolated number floating in a health dashboard.\nVO2 max belongs with your runs. That\u0026rsquo;s where the context is.\n","date":"15 January 2026","externalUrl":null,"permalink":"/diary/vo2max-on-your-run/","section":"Dev Diary","summary":"VO2 max is the single number that best captures your aerobic fitness — but Apple buries it in the Health app, disconnected from any specific run. Apex Run reads it from HealthKit and ties it back to the run that produced it.","title":"Bringing VO2 max to your run","type":"diary"},{"content":"For most of my running life, every app showed me the same thing: distance, duration, pace. That trio is a reasonable default. It\u0026rsquo;s also a blunt instrument.\nWhen I started a heart-rate base-building block last spring, I didn\u0026rsquo;t care about pace at all — the whole point was to ignore pace and stay in zone 2. But every time I scrolled my run list, pace was right there, judging me. I had to mentally filter out the number I was training myself to stop chasing.\nWhat you see shapes what you think about. A run list isn\u0026rsquo;t just a log — it\u0026rsquo;s a daily signal of what your training is for.\nChoosing your two # Besides Distance (always displayed), the run list in Apex Run lets you pick exactly two metrics to display on each run card. The options cover everything the app tracks:\nDuration Pace Avg. heart rate Calories Power Stride length Cadence Two slots. Pick the ones that reflect your current training focus. If you\u0026rsquo;re deep in a base phase, you might want distance, duration, and average heart rate. If you\u0026rsquo;re chasing a 5K PR, maybe pace, cadence, and heart rate. If you\u0026rsquo;re experimenting with power-based training, swap pace out for watts.\nThe configuration lives in Settings and takes ten seconds to change.\nWhy it matters more than it sounds # Metrics you don\u0026rsquo;t care about right now aren\u0026rsquo;t neutral — they\u0026rsquo;re noise. Seeing a slow pace when you\u0026rsquo;re deliberately running easy, or seeing low calorie burn when you\u0026rsquo;re focused on long-slow-distance, creates a small friction every time you open the app.\nRemoving that friction means your run list becomes a clean record of the thing you\u0026rsquo;re actually building. A month of heart-rate data, lined up in a list, tells a story that a month of mixed signals can\u0026rsquo;t.\nChange the metrics when your training focus changes. The app should reflect where you are, not where you were.\n","date":"11 January 2026","externalUrl":null,"permalink":"/diary/customize-metric-display/","section":"Dev Diary","summary":"Distance and pace aren’t always what you care about. During a heart-rate base-building block, I wanted HR front and center. During a power training cycle, I wanted watts. The run list should show you what matters right now — not a fixed default.","title":"Your run list, your metrics","type":"diary"},{"content":"I built Apex Run for one reason: running deserves a dedicated tool. Not a general fitness tracker that also handles cycling and swimming — something built entirely around gathering and analyzing running data, for runners who actually care about the numbers.\nMost running apps make you start fresh. You download something new, and it greets you with an empty screen. Your entire running history — years of early mornings, long runs, race days — sits in Apple Health, and the app just ignores it.\nThe very first thing I wanted from Apex Run was for it to feel immediately useful. Not a blank slate waiting to be filled — a picture of who you already are as a runner, starting to take shape the moment you open it.\nHow syncing works # When you open Apex Run for the first time, it begins syncing your Apple Health history right away — starting from your most recent runs and working backward through time. Recent data arrives first, so you\u0026rsquo;re not staring at an empty screen while the app catches up.\nIf you have years of history, the full sync may take a while to complete in the background. That\u0026rsquo;s fine — you can start exploring your recent data immediately. And if you ever need to continue sync, there\u0026rsquo;s a manual trigger in Settings that picks up where it left off.\nEvery run you\u0026rsquo;ve ever recorded through Apple Watch or a third-party app that writes to Apple Health is included:\nAll workout routes and GPS tracks Heart rate, pace, cadence, and power data Personal bests at standard distances (1K through marathon), calculated using a sliding window over your full history Cumulative stats: total distance, total time, longest run Why it matters # A running app that only knows about the last few weeks of your training is missing the point. The most meaningful numbers — your VO2 Max trend over six months, your long-run progression, whether your fitness is actually improving — only become visible over time.\nZero Cold Start means Apex Run earns your trust on day one by respecting the history you\u0026rsquo;ve already built.\n","date":"10 January 2026","externalUrl":null,"permalink":"/diary/zero-cold-start/","section":"Dev Diary","summary":"I built Apex Run for one reason: running deserves a dedicated tool. Not a general fitness tracker that also handles cycling and swimming — something built entirely around gathering and analyzing running data, for runners who actually care about the numbers.","title":"Zero cold start","type":"diary"},{"content":"","externalUrl":null,"permalink":"/categories/","section":"Categories","summary":"","title":"Categories","type":"categories"},{"content":"","externalUrl":null,"permalink":"/learn/","section":"Running Reference","summary":"","title":"Running Reference","type":"learn"},{"content":"","externalUrl":null,"permalink":"/tags/","section":"Tags","summary":"","title":"Tags","type":"tags"}]