Build your Mission Bay Triathlon plan
Your coach opens with the Mission Bay Triathlon set for October (an estimate until the date is announced), asks about your week and your fitness, then writes every session of your Olympic-distance triathlon plan. Free, and you can start as a guest. About 51 weeks to go.
Start your Mission Bay Triathlon plan- Formats
- International, Sprint
- Terrain
- Flat
- Field
- The International distance is capped at 300 athletes
Mission Bay Triathlon distances
- International 0.6 mi swim, 21.1 mi bike, 5.6 mi run
- Sprint 0.3 mi swim, 10.6 mi bike, 3.1 mi run
Course
The Mission Bay Triathlon course
The Mission Bay Triathlon is one of San Diego's oldest, with its 38th edition in 2026, and it is raced on the calm water and flat shoreline of Mission Bay, with the bike heading out to Fiesta Island. The International distance is a 1,000-meter swim, 34K bike and 9K run, and the sprint is 500 meters, 17K and 5K; wave starts begin at 6:40 a.m., with colored caps by wave.
Read the full course notes
The protected bay swim is about as gentle as open water gets, and the bike laps around Fiesta Island are flat and fast, so it is a ride about holding a steady position rather than climbing. The run follows the bayside paths on the same flat ground, and the San Diego 5K runners share the bay course. Course maps, lap counts and the wave plan are posted on the race site before race week.
- Terrain
- Flat
- Formats
- International, Sprint
- Field
- The International distance is capped at 300 athletes
- Race-day conditions
- October in San Diego usually means 61–75 °F days, with a mild, often cloudy start and sun later in the morning. NOAA's San Diego Bay gauge averages about 69 °F in October, so most athletes swim in a wetsuit (the title sponsor makes them). Light winds are typical, but sea breezes can pick up on the open Fiesta Island loop, so hold a stable, aero position.
What to train for
This is a fast, flat race, so train for speed you can hold: on the bike, ride 3 to 4 x 8 to 10 minutes at goal effort on flat roads, staying aero, and count laps in training the way you will around Fiesta Island.
Practice wave starts and sighting in open water, swimming the first 200 meters hard and then settling.
Run 4 to 6 x 1K at 10K pace on flat paths, and finish each week with a brick: 45 minutes on the bike straight into 15 to 20 minutes at goal run pace. If the swim is ever cancelled for water quality, the organizers replace it with a short run, so a few run-bike-run sessions are useful insurance.
Sample week
A sample Mission Bay Triathlon training week
A week from the middle of the build, about six weeks out. Your plan sets the real distances and paces from your own fitness and adjusts them every week as you train.
- Monday
- Swim, 45 min: drills and technique
- Tuesday Key session
- Bike, 1 h with threshold intervals
- Wednesday
- Swim, 45 min: steady intervals at race effort
- Easy run, 40 min
- Thursday Key session
- Run, 40 min with tempo segments
- Friday
- Rest, or 20 minutes of mobility
- Saturday Key session
- Long ride, 1 h 30 min, then a 20 min run off the bike
- Sunday
- Long run, 1 h easy
Taper
Tapering for the Mission Bay Triathlon
Start the taper seven to ten days before race day. Trim the volume in all three sports, keep short race-pace efforts in each, and do one last short brick so running off the bike still feels familiar. The course is flat, so pacing decides the day: rehearse your goal pace in short segments during race week.
Also in Claude
Ask Claude for this plan
Add AthleteSpace to Claude once, then paste this prompt and put in your own numbers.
Build me a Olympic-distance triathlon season for the XTERRA WETSUITS Mission Bay Triathlon & 5K in October. I train about [hours] hours a week, [days] days a week.
Mission Bay Triathlon training questions
How long should I train for the Mission Bay Triathlon?
Most athletes give a Olympic-distance triathlon twelve to sixteen weeks of focused training on top of an existing base. The coach counts back from your actual race date, so if you have less time than that it builds the best plan the remaining weeks allow rather than pretending you have longer.
What is the Mission Bay Triathlon course like?
Flat. The Mission Bay Triathlon is one of San Diego's oldest, with its 38th edition in 2026, and it is raced on the calm water and flat shoreline of Mission Bay, with the bike heading out to Fiesta Island.
How cold is the water at the Mission Bay Triathlon?
October in San Diego usually means 61–75 °F days, with a mild, often cloudy start and sun later in the morning. NOAA's San Diego Bay gauge averages about 69 °F in October, so most athletes swim in a wetsuit (the title sponsor makes them). Light winds are typical, but sea breezes can pick up on the open Fiesta Island loop, so hold a stable, aero position.
When should I start tapering for the Mission Bay Triathlon?
Start the taper seven to ten days before race day. Trim the volume in all three sports, keep short race-pace efforts in each, and do one last short brick so running off the bike still feels familiar. The course is flat, so pacing decides the day: rehearse your goal pace in short segments during race week.
Do I need an account to get a Mission Bay Triathlon training plan?
Start as a guest and save a free account later. Your coach writes your Olympic-distance triathlon plan and adapts it every week as you log your training. No card.