Ability.ICU operates as a mathematical intelligence layer atop your raw endurance sensor streams. Before our predictive algorithms can generate meaningful insights, you must anchor your personal physiological parameters and connect your telemetry pipelines.
đ Telemetry Ingestion Architecture
â đ˛
Sensors & Devices
Garmin, Wahoo, Power Meters
→
âī¸ đ
Cloud Sync
Intervals.icu / Strava APIs
→
âī¸ đ§
Ability.ICU Parser
NP, TSS, hrSS, W', EF
→
đ đ¯
Dashboard & PMC
Fitness, Fatigue & Form
1. Key Baselines You Must Define
Navigate to Profile Settings → Heart Rate Zones & Thresholds or launch the interactive Setup Guide Wizard to establish these values:
⥠FTP (Functional Threshold Power)
Expressed in Watts. The maximum quasi-steady power you can maintain for ~60 minutes. Every training zone (Z1âZ7), Normalized Power calculation, and Training Stress Score (TSS) is scaled against this number.
â¤ī¸ LTHR (Lactate Threshold Heart Rate)
Expressed in beats per minute (bpm). Your heart rate at lactate balance (typically 85â92% of Max HR). Powers our Heart Rate Stress Score (hrSS) and Joe Friel 5-Zone cardiac model.
đ W' (W-Prime / Anaerobic Work Capacity)
Expressed in kilojoules (kJ), typically 12â28 kJ. Your finite anaerobic battery tank above Critical Power. Allows real-time modeling of battery depletion and reconstitution during hard climbs or sprints.
đ Max & Resting Heart Rate
Used to calculate Heart Rate Reserve (HRR) via the Karvonen method. Critical for accurate Banister TRIMP exponential stress weighting.
đĄ Best Practice: When to Re-Test Baselines
Re-evaluate your FTP and LTHR every 6 to 8 weeks, especially at the conclusion of a structured build mesocycle. In Ability.ICU, updating your FTP automatically applies to all new workouts, and you can choose whether to recalculate historical training scores in your profile preferences.
2. Connecting Ingestion Sources
1
Intervals.icu Integration
Enter your Intervals Athlete ID and API key in Settings → Integrations for instant, high-frequency synchronization of power records, wellness metrics, and calendar items.
2
Strava OAuth Link
Authorize Strava with 1 click to automatically stream new public cycling, running, and swimming sessions into your Ability.ICU feed the moment you end recording.
3
Direct FIT / TCX Upload
Have a raw workout file from Garmin, Wahoo, or GoldenCheetah? Navigate to Activities → Create or Import to parse 1Hz sensor streams locally.
The "Today" page (/today) is your primary launchpad each morning. It synthesizes complex multi-week trends into immediate, actionable answers to three vital daily questions:
- How ready is my body to train today? (Form status, TSB gauge, acute fatigue).
- What is on my scheduled training menu? (Structured workout, planned TSS, interval targets).
- What key events or team sessions are approaching? (Countdown to squad camps, target races, or gran fondos).
đ§ Daily Training Decision Matrix
đĸ Fresh & Ready (TSB > +5)
Your body is supercompensated and fully recovered. Ideal window for high-intensity VO2max intervals, breakthrough power tests, or race execution.
đĄ Productive Fatigue (TSB -10 to -25)
The sweet spot for physiological adaptation. Normal training fatigue is present. Execute scheduled endurance or threshold sessions as planned.
đ´ Excessive Fatigue (TSB < -30)
Overreaching threshold reached. If combined with high RPE or poor sleep, convert intense intervals into active recovery (Z1 spin) or complete rest.
Workout Pairing & Compliance
When you complete a workout that was scheduled on your calendar, Ability.ICU automatically compares the Planned TSS vs. Completed TSS and Target Duration vs. Actual Duration. A compliance score is computed, letting you and your coach monitor adherence without manual data entry.
View today's readiness and scheduled program:
Check your training targets and power zones for today.
Open Today Dashboard →
Random training produces random results. The Training Center (/training) enables full classical and block periodization. You can plan individual workouts, schedule multi-week mesocycles (Base, Build, Peak, Taper), and track targeted weekly hours and TSS volumes.
đ
The 3:1 Mesocycle Periodization Model
Week 1: Progressive Load
Target: 450 TSS
Build foundational volume
Week 2: Overload
Target: 520 TSS
Introduce intensity intervals
Week 3: Peak Overload
Target: 590 TSS
Highest structural strain
Week 4: Deload & Recovery
Target: 280 TSS
Supercompensation adaptation
How to Schedule a Planned Workout
- Navigate to the Training Calendar.
- Click on any future date cell.
- Choose an existing workout from your library or type a new workout with estimated duration (minutes) and targeted TSS.
- Watch your future PMC line adjust automatically: Ability.ICU projects your upcoming CTL and TSB based on your scheduled sessions!
âšī¸ Forecasted PMC Trajectories
When you schedule future workouts on your calendar, the Performance Management Chart renders dashed projection curves into the future. This lets you precisely simulate a 2-week race taper before you execute it, ensuring your Form (TSB) hits +15 to +20 on race morning!
Ready to structure your upcoming weeks?
Open the calendar to schedule workouts, blocks, and targets.
Open Training Calendar →
The Workout Builder (/workouts/builder) allows athletes and coaches to author sophisticated, multi-step structured training programs with exact power targets, duration, cadence constraints, and coach notes.
đģ Declarative Workout Syntax Example
Sweet Spot Over-Unders
Warmup:
- 10m ramp 50-75% FTP 90rpm "Gradual spin to activate legs"
Main Set:
3x:
- 3m 95% FTP 92rpm "Under interval"
- 2m 105% FTP 96rpm "Over threshold burst"
- 2m 55% FTP 85rpm "Active recovery valley"
Cooldown:
- 10m 50% FTP 85rpm "Easy cool down spin"
Key Features of the Builder
- Real-Time Intensity Profiler: As you type or adjust intervals, Ability.ICU calculates estimated duration, Normalized Power (NP), Intensity Factor (IF), and estimated TSS in real time.
- Multi-Format Export: Export your workout directly to
.MRC (Computrainer), .ERG, or .ZWO (Zwift / Wahoo / Garmin) for indoor trainer execution.
- Cadence & HR Targets: Specify optional target RPM and target % LTHR alongside power steps.
Every completed workout contains high-resolution telemetry. Ability.ICU transforms raw GPS, power, cadence, and heart rate streams into clinical diagnostics on the Activity View.
đ Efficiency Factor (EF) & Aerobic Decoupling
Efficiency Factor (EF = NP / HR)
Measures how many Watts of mechanical power you generate per single heartbeat. As aerobic fitness improves, EF rises: you produce more power at lower cardiac cost.
Cardiac Drift / Decoupling (< 5%)
Compares EF in the 1st half of a steady workout vs the 2nd half. Decoupling under 5% proves superior aerobic durability; drift above 5% indicates hydration deficits, heat stress, or aerobic ceiling exhaustion.
Breakthrough Detection
Whenever you surpass your rolling season peak power for key benchmark durations (5 seconds, 1 minute, 5 minutes, 20 minutes, or 60 minutes), Ability.ICU flags the workout with an automated Breakthrough Badge, prompting an optional FTP adjustment recommendation.
Explore your activity feed and diagnostic streams:
Review past workouts, laps, and peak power achievements.
View Activities →
Sensors only measure mechanical output (Watts and heartbeats); they cannot measure your mental state, muscle soreness, or systemic life stress. Ability.ICU bridges this gap with Carl Foster's validated Session RPE (sRPE) model.
đ§ Borg CR-10 Subjective Exertion Spectrum
1-2
Very Easy
3-4
Moderate
5-6
Hard / FTP
7-8
Very Hard
9-10
Maximal / Fail
The Fatigue Gap Diagnostic Formula
sRPE Load = Borg Rating (1â10) × Duration (minutes)
Fatigue Gap = Normalized sRPE Load - Normalized Sensor TSS
â ī¸ Detecting The Danger Signal: High RPE + Low Power
If an easy Zone 2 recovery ride feels like an 8/10 on the Borg scale and your heart rate refuses to rise, your Fatigue Gap will spike into the red. This is the hallmark clinical indicator of autonomic nervous system exhaustion or sub-clinical viral infection. Stop training immediately and schedule a 48-hour recovery window.
The Performance Management Chart (PMC) is the gold standard mathematical engine for endurance training. It quantifies your chronic training history as a dual-component impulse-response model:
đ CTL (Fitness)
42-Day Time Constant
Represents your cumulative aerobic engine. Rises slowly over months of consistent volume; drops slowly when you rest.
đĨ ATL (Fatigue)
7-Day Time Constant
Represents immediate stress from workouts over the past week. Spikes rapidly during hard blocks; sheds rapidly in 4â7 days of rest.
⥠TSB (Form)
Formula: CTL - ATL
Your racing readiness. Positive numbers reflect fresh legs. Negative numbers reflect fatigue adaptation.
đ¯ The Golden TSB Performance Zones
| TSB Range |
Status Name |
Physiological Implication & Recommendation |
| > +25 |
Transition / Detraining |
Too rested. Aerobic fitness (CTL) is actively declining. Re-introduce training stress. |
| +10 to +25 |
Race Ready / Peaked |
Optimal for target race day! High freshness with maximal preserved fitness. |
| -10 to +10 |
Neutral / Maintenance |
Good for weekend group rides, tempo maintenance, or transitioning between mesocycles. |
| -10 to -30 |
Productive Training |
Optimal training zone! Drives steady aerobic adaptations without excessive breakdown. |
| < -30 |
High Risk / Overreaching |
Elevated risk of injury, immune suppression, and hormonal fatigue. Schedule recovery. |
Explore mathematical modeling and decay equations:
Read the complete mathematical derivation of the PMC.
Deep-Dive PMC Science →
Two riders with identical FTP (e.g. 280W) can be completely different athletes: one may have a 1,400W sprint and struggle on 20-minute climbs, while the other can sustain 350W for 5 minutes but cannot sprint past 800W. Ability.ICU supports dual power profiling architectures:
⥠Critical Power (CP) & W'
A 2-parameter mathematical asymptote: CP is your true aerobic boundary, and W' is your finite anaerobic fuel tank (in kJ). When you exceed CP, W' depletes; when you pedal below CP, W' reconstitutes.
Ideal for: Time trialists, gravel racers, triathletes, steady endurance.
đŦ 4-Day Performance (4DP)
Evaluates power across 4 distinct metabolic domains:
- NM (5-second): Neuromuscular explosive sprint power.
- AC (1-minute): Anaerobic Glycolytic capacity.
- MAP (5-minute): Maximal Aerobic Power (VO2max ceiling).
- FTP (20-minute): Sustained lactate threshold power.
Coaches can manage multiple athletes or full squads from a single unified cockpit on the Coaching Dashboard (/coaching).
1
Invite Athletes
Enter the athlete's email address to send a coaching link. Once accepted, the athlete appears in your roster with real-time status indicators.
2
Assign Training
Coaches gain write access to the athlete's Training Calendar, allowing direct placement of workouts, intervals, and target notes.
3
Monitor Readiness
Receive real-time warnings if an athlete enters deep fatigue (TSB < -30), logs an elevated Fatigue Gap, or fails workout targets.
Open the Coaching Dashboard:
Oversee your linked athletes, invites, and squad statuses.
Open Coaching Hub →
Ability.ICU combines high-performance sports analytics with collaborative community capabilities, backed by enterprise-grade privacy controls.
đĨ Clubs & Feed
Join institutional clubs, follow peers, post kudos, and participate in club forums. Verified club badges ensure legitimate team ownership.
đĄī¸ Guardian Oversight Mode
A protective interface for athletes under 21. Parents or health guardians can monitor training load and health metrics in a read-only mirror interface, safeguarding young athletes.
Data Sovereignty & Privacy
Your data is your property. You can download all telemetry, activities, and PMC history in raw JSON, FIT, or CSV format at any time via Profile Settings → Account & Data Management.
Explore community clubs and team feeds:
Connect with fellow athletes and discover verified cycling clubs.
Explore Clubs →