Triathlon coaching email after a Strava activity update

Triathlon coaching email after a Strava activity update

An n8n workflow that listens to Strava. When an activity is updated, it flattens the activity's data into text, asks a
Google Gemini chat model to answer as a triathlon coach, turns the answer into HTML and emails it to you.

What is inside

• workflow.json: the workflow as n8n exports it, fifteen nodes: eight that run, two spare ones that are not
  connected and five sticky notes. It holds no credential.
• README.md: these notes.

What we changed from the original copy

• The credential links are gone: the Strava, Google Gemini, SMTP, Gmail and WhatsApp accounts. Select your own.
• Google Gemini Chat Model named models/gemini-2.0-flash-exp. Google's deprecations page, read on 12 November 2026,
  says the gemini-2.0-flash family shut down on 1 June 2026 and names gemini-3.6-flash as its replacement. The model
  is now models/gemini-3.6-flash. The 2.0 experimental name is not on that page, so it may have been retired
  earlier.
• The email addresses in Send Email and Gmail are now <YOUR_EMAIL_ADDRESS> and <YOUR_SENDER_ADDRESS>.
• The note that asked for donations and carried the author's links is now a title. The text of the other notes stays.
• Nothing else. The Code nodes needed no repair.

Before you start

• An n8n instance that Strava can reach over the internet, on n8n Cloud or your own server. The trigger registers a
  webhook with Strava, so a local address does not work.
• A Strava account and an API application, made at https://www.strava.com/settings/api. n8n's Strava credential asks
  for the application's client ID and secret.
• A Google Gemini API key.
• An SMTP account for sending the email, and the addresses to send from and to.

Set it up

1. In n8n, create a workflow, open its menu and choose Import from File. Pick workflow.json.
2. Add a Strava OAuth2 credential with your application's client ID and secret, and select it in Strava Trigger. The
   credential's default scopes are activity:read_all and activity:write.
3. Add a Google Gemini (PaLM) credential with your API key and select it in Google Gemini Chat Model.
4. Add an SMTP credential and select it in Send Email. Replace <YOUR_EMAIL_ADDRESS> with the address that receives
   the notes and <YOUR_SENDER_ADDRESS> with the address you send from. Keep the angle brackets out.
5. Save, then press Publish. n8n registers the webhook with Strava when the workflow goes live.
6. Edit an activity in Strava, such as its title. A few moments later the coaching notes arrive by email.

Strava allows one webhook subscription for each application. If the application already has one, the trigger stops
with that message. Its option Delete If Exist removes the old subscription, and that is a destructive step.

How a run goes

1. Strava Trigger fires on an activity update. With its resolveData setting on, which is the node's default, it also
   fetches the activity from Strava and adds it as object_data, so the data holds the full record.
2. Code adds a field named myNewField set to 1 to each item. It came with the file and changes nothing that matters.
3. Combine Everything flattens the data into lines of text, one name: value line each.
4. Fitness Coach is an AI Agent. Its prompt describes a triathlon coach with notes for pool and open water swims, rides
   and runs, brick workouts and recovery, then ends with the activity text. Google Gemini Chat Model is the model it
   uses.
5. Structure Output splits the answer into headings, paragraphs and lists. Conver to HTML joins them into one HTML
   string.
6. Send Email sends that HTML with the subject New Activity on Strava.

Gmail and WhatsApp Business Cloud sit in the file with no connection to anything. The note beside them says the
answer could go by WhatsApp, email or a blog. To use one, connect it after Conver to HTML, and fill in what it asks.

Change the look

• The coach: the prompt in Fitness Coach. It names no goals and no athlete profile, so add yours there.
• The model: Google Gemini Chat Model.
• Which activities start a run: the Event and Object in Strava Trigger. Set the event to Create to coach each new
  upload.
• The email: the subject and sender in Send Email.

Good to know

• The trigger's event is update. Strava, on its webhook page read on 12 November 2026, sends an update when an
  activity's title, type or privacy changes. A new upload sends a create event. To coach every new activity, set the
  event to Create in Strava Trigger.
• Strava gives each application one subscription. The one this trigger makes covers every athlete who authorised your
  application.
• The answer is in plain markdown. Structure Output turns bold headings, * bullets and numbered lists into HTML. Other
  markdown, such as tables or # headings, arrives as plain text.
• The prompt asks the coach to use the athlete's goals and profile, and the workflow sends none. The advice rests on the
  one activity.
• Strava's API agreement, read on 12 November 2026, says a user's Strava data may only be shown to that user and not
  shared with third parties without consent. Here the activity data goes to Google's Gemini. Use it on your own
  account, and read the agreement before you use it for anyone else.
• The advice is general. Check it before you change your training because of it.
• Google lists gemini-2.5-pro and gemini-2.5-flash for shutdown on 1 December 2026, so the model name will need
  a change if you pick one of those.
• Your data: each activity's data goes to Google, and the email goes through your SMTP server.
• Credentials: the JSON holds none.