Question 1

Where can I learn more about the science and AI behind AthleteSpace?

Accepted Answer

Learn more about our scientific foundations and AI methodology on our Science & AI page.

Question 2

What is AthleteSpace?

Accepted Answer

AthleteSpace is a free training app for running, triathlon, cycling, HYROX, swimming and functional fitness. It builds a plan for your goal, adapts it every day to the workouts you complete and, if you connect a watch or ring, to your sleep and recovery. An AI coach answers questions about any session.

Question 3

What happens when I miss a workout?

Accepted Answer

Nothing breaks. Each night the coach revises the coming days from what you actually did, so the week re-balances around the missed session and your race date stays where it is. You can also tell the coach why you missed it (sick, travelling, a long day) and it adjusts the next sessions to match. Every change comes with its reason written out.

Question 4

What science is AthleteSpace based on?

Accepted Answer

AthleteSpace is built on widely used endurance training models: the fitness-fatigue model (long-term Fitness, short-term Fatigue and Form, the gap between them), training load from power or pace relative to your threshold, Banister TRIMP (heart-rate impulse), and session RPE. These approaches rest on decades of peer-reviewed research, and the Science page lists the key papers.

Question 5

Who builds AthleteSpace?

Accepted Answer

One person: Bruno Artacho, an endurance athlete and engineer in Nashville with a PhD in AI, who previously built AI systems at Amazon and Google. AthleteSpace does not invent new physiology. It applies published, peer-reviewed training models, and every plan passes the same fixed safety rules before you see it.

Question 6

How does AthleteSpace measure training stress?

Accepted Answer

We calculate training stress using the best available data for each session. When power or pace data is available, we use intensity relative to your personal threshold. When it is not, we fall back to heart-rate physiology models or perceived effort. AI ensures everything is converted into a single, consistent training load scale.

Question 7

What are Fitness, Fatigue, Form and Training Load?

Accepted Answer

Training Load measures how demanding one workout was. Fitness is your long-term load, built over about six weeks. Fatigue is your short-term load from the last week or so. Form is Fitness minus Fatigue: positive means fresh, very negative means you are carrying a lot of fatigue.

Question 8

Why not just track heart rate, pace, or mileage?

Accepted Answer

Single metrics are often misleading. Physiological stress is not linear, and the same pace or heart rate can represent very different strain depending on fatigue, heat, terrain, and fitness. AthleteSpace uses non-linear, science-backed models that better reflect how the body actually responds to training.

Question 9

Does AthleteSpace work if my data is incomplete?

Accepted Answer

Yes. AthleteSpace is designed for real-world training. If some sensors are missing or unreliable, AI automatically selects appropriate fallback models and maintains continuity in your fitness and fatigue tracking.

Question 10

How does the AI coach work?

Accepted Answer

The AI coach analyzes your training load, recovery trends, and recent patterns to provide context-aware recommendations. It helps answer questions like when to push, when to back off, and when recovery matters more than intensity, using both data and established training principles.

Question 11

Does AthleteSpace replace a human coach?

Accepted Answer

No. AthleteSpace is a decision-support tool. It helps athletes and coaches make better-informed choices, improves consistency, and highlights risk or opportunity, but it does not replace human judgment or coaching relationships.

Question 12

How does AthleteSpace use Apple Health and HealthKit?

Accepted Answer

On iOS devices, AthleteSpace uses Apple HealthKit to read your workout data, heart rate, active energy burned, running distance, and cycling distance. When you allow it, workouts you record in AthleteSpace are also saved to Apple Health, including the route. All HealthKit data is used solely to provide personalized training insights and performance analysis. Your health data is never shared with third parties or used for advertising. You can connect or disconnect Apple Health at any time in Settings > Integrations.

Question 13

What data does AthleteSpace collect?

Accepted Answer

With your explicit consent, AthleteSpace collects training and wellness data from connected platforms such as activity details, heart rate, recovery indicators, and training load metrics. We only collect data you authorize and only for performance and training insight purposes.

Question 14

How is my data used?

Accepted Answer

Your data is used solely to generate personalized training insights, fitness and fatigue trends, and AI-driven recommendations. AthleteSpace does not sell or share individual user data with advertisers or third parties.

Question 15

Is my data secure?

Accepted Answer

Yes. We use secure communication protocols and encrypted storage to protect your data. Access is limited to systems required to provide the service you've authorized.

Question 16

Does AthleteSpace provide medical advice?

Accepted Answer

No. AthleteSpace does not provide medical diagnosis or treatment. All insights are for training and performance purposes only. Always consult a qualified healthcare professional for medical concerns.

Question 17

Is AthleteSpace free to use?

Accepted Answer

Yes. AthleteSpace is free: no subscriptions, no in-app purchases and no paid features. No ads, and we never sell your data. Fair-use limits on coach chat and form analysis keep it free for everyone.

Question 18

Can I use AthleteSpace inside Claude?

Accepted Answer

Yes. Add the AthleteSpace connector to Claude and ask for a running plan in the chat: you get every week, every run, training paces and predicted race times, with no account needed. Setup takes a minute:

Frequently asked questions

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