Terms of service
Last updated 7 September 2026
These terms cover your use of Sinew, training-plan software run by Jeremy Ettlinger. By signing in you accept them. If you do not, do not sign in. Questions go to jeremy.ettlinger@gmail.com.
What Sinew is right now
Early software, offered free to a small number of coaches while it is being built with them. Features may change or be withdrawn, and there is no uptime commitment. You will be given reasonable notice and a way to export your data before anything is withdrawn that would lose your work.
Your account
You need a Google account to sign in, you must be at least 18, and you are responsible for what happens under your account. Tokens you generate to connect an AI client carry your full access to your own data, so treat them like passwords and revoke any you no longer use.
Athlete information
You are responsible for having the right to record what you record. Only enter information about an athlete that they know you keep and would expect a coach to keep. Do not enter medical records, health-insurance information, government identifiers, payment details, or information about anyone under 18. If an athlete asks you to remove what you hold about them, you can delete it yourself at any time.
Plans are not medical advice
Sinew helps you write and compare training plans, including candidate plans drafted by an AI model. Those drafts are suggestions and nothing more. They are not medical, physiotherapy, or nutritional advice, they are not reviewed by anyone qualified before they reach you, and they can be wrong in ways that would injure someone. You are the practitioner: every plan an athlete follows is one you have read and judged suitable for that person. Neither Sinew nor its author is responsible for injury or loss arising from a plan you adopt.
Who owns what
Your plans, playbooks, notes and athlete records are yours. You grant only the permission needed to store and display them back to you and to run the service. Sinew owns its own software. The exercise library is from wger, used under CC BY-SA 4.0.
Acceptable use
Do not use Sinew to break the law, to store someone else's information without a basis for holding it, to attack or overload the service, or to try to reach another practitioner's data. Accounts doing any of these can be suspended.
No warranty, and the limit of liability
Sinew is provided as-is, with no warranty of any kind. It may be unavailable, and despite daily backups it may lose data, so keep your own copy of anything you cannot afford to lose; you can export everything from Settings at any time. To the fullest extent the law allows, the author is not liable for lost profits, lost data, or any indirect or consequential loss. Nothing here limits liability that cannot legally be limited.
Ending it
You can delete your account whenever you like from Settings; deletion is reversible for 30 days and permanent after that. Access may be ended if these terms are broken, with notice and a chance to export first except where that is impossible.
How your data is handled is described in the privacy policy.