Terms & Conditions

Terms & Conditions of the online store and privacy policy. The Seller is Adrian Kostera, Sevenum (Netherlands), KVK 83562303, VAT NL003838850B77, contact: adrian@adriankostera.com.

§ 1. General

The store is operated by Adrian Kostera, a sole proprietorship registered in the Netherlands (KVK 83562303, VAT NL003838850B77), hereinafter the “Seller”.

These Terms set out the rules for the sale of digital and physical products and services offered in the store at adriankostera.com.

The Buyer may be a natural person with full legal capacity, a legal person or an organisational unit.

§ 2. Products and services

Training plans — an individual coaching service delivered on a monthly basis (subscription), including the preparation and management of the plan via the TrainingPeaks platform and contact as defined by the chosen package.

Diet plans — individual nutrition plans prepared on the basis of a completed form; selected packages are delivered on a monthly basis.

eBook and PlayBook — digital content (PDF/EPUB files) delivered electronically.

Printed book — a physical product shipped to the address provided.

§ 3. Prices and payment

Prices shown in the store include applicable taxes. Prices are presented in Polish zloty (PLN) or euro (EUR) depending on the site version and market.

Payments are processed by Stripe. By paying, the Buyer accepts the payment provider’s terms.

The contract is concluded upon successful payment (for subscriptions — the first payment).

§ 4. Subscriptions

Training plans and selected diet packages are subscriptions that renew automatically each month until cancelled.

The Buyer may cancel a subscription at any time — via the subscription-management link (Stripe portal) received by e-mail, or by contacting the Seller.

Cancellation takes effect at the end of the current, paid billing period. Amounts for a started period are non-refundable (subject to § 6).

§ 5. Delivery

Digital content (eBook, PlayBook) is made available immediately after payment is confirmed — via a download page or e-mail.

Plans and diets are delivered after the Buyer completes the intake form; the first cycle is usually prepared within a few business days.

The printed book is shipped to the address given at checkout, within the timeframe stated in the confirmation.

§ 6. Right of withdrawal

A consumer has the right to withdraw from the contract within 14 days without giving a reason, unless the law provides otherwise.

For digital content delivered immediately, by agreeing to the start of performance before the withdrawal period ends the Buyer acknowledges the loss of the right of withdrawal once the file is made available.

For individual services (plans, diets) prepared to order and tailored to the Buyer, the right of withdrawal may not apply once performance has begun.

For the printed book, the right of withdrawal applies under general rules; the cost of returning the goods is borne by the Buyer.

§ 7. Complaints

Complaints should be sent to adrian@adriankostera.com. The Seller will handle a complaint within 14 days.

In the event of a defect in a digital or physical product, the Buyer has the rights arising from generally applicable law.

§ 8. Personal data — Privacy Policy

The data controller is the Seller. Data is processed to fulfil orders, manage subscriptions, provide contact and — with consent — for marketing.

Scope of data: e-mail address, data necessary to provide the service (e.g. from the training/diet form) and, for the book, a shipping address. Payment data is processed solely by Stripe; the Seller does not store card data.

Data recipients: Stripe (payments), Netlify (hosting), Google (statistics — Google Analytics), TrainingPeaks (plan delivery). Data may be processed outside the EEA under standard safeguards.

Legal bases: performance of the contract, legal obligation (e.g. accounting), legitimate interest and consent.

The Buyer has the right to access, rectify, erase, restrict, port and object to the processing of their data, and to lodge a complaint with a supervisory authority. Contact: adrian@adriankostera.com.

§ 9. Final provisions

Matters not covered here are governed by Dutch law.

The Seller may amend these Terms for important reasons; orders placed before a change are governed by the Terms in force at the time of purchase.

These Terms do not constitute legal advice and may require adjustment by the Seller to a specific legal situation.

Last updated: August 2026.