Triathlon Plan

AI-built triathlon training plan

Q: What's the right starting distance?

Sprint unless you have a deep prior base. Sprint teaches you to compete in triathlon, manage transitions and nutrition without long-duration pressure. Coming from running with 5+ years and already swimming 1500 m comfortably? You could start with Olympic, but the first race — Sprint or Olympic — teaches you more about logistics than any training. Starting with 70.3 without a Sprint is suboptimal: it dramatically increases DNF (Did Not Finish) risk.

Q: How long do I need to prepare for a 70.3 or an Ironman?

70.3 : 16-24 weeks with a previous Olympic and solid aerobic base (6+ months training triathlon regularly). Otherwise, plan 28-32 weeks. Ironman : 24-32 weeks with a completed Half Ironman and minimum 12 months base. Without that prior base, the recommended plan is to first prep 70.3 (16-24 weeks), race it, then start Ironman 6-12 months later.

Q: How many hours per week will I train?

Depends on distance and block. Sprint : 5-7 h/week (the entire plan). Olympic : 7-10 h/week (load blocks 10-12 h). 70.3 : 8-12 h/week average (load blocks 14-16 h). Ironman : 10-15 h/week average (load blocks 18-22 h). Ironman demands a structured life: 6-7 sessions/week, minimum 1 double session (morning + evening) one day per week.

Q: Do I need a human coach beyond the AI plan?

For beginners and Sprint/Olympic, EntrenAI covers 90 %. For 70.3, the plan is complete but we recommend at least one in-person swim session with a coach to correct technique (the discipline with the largest gain potential). For Ironman, we recommend a human coach if you're racing for category/Kona qualification — a personalized coach can dial in the final 5-10 % no standard plan reaches. To participate and enjoy Ironman, EntrenAI is enough.

Q: How are injuries handled during prep?

Reporting acute joint pain, EntrenAI deactivates the affected discipline and compensates with the other two. Leg injury (tibia, knee, ankle)? The plan reduces run volume and increases swim + bike. Shoulder (swim-related)? Reduce swim, increase bike + run. Missing 2+ consecutive weeks in any discipline triggers a step-back and event date reassessment if realistic . Never race with acute pain: a mismanaged injury ends an event.

Q: What if I only have 4-5 hours/week? Can I do a 70.3?

Honestly, not recommended. With 4-5 h/week it's very hard to reach 70.3 properly prepared — you'll likely finish but with frustrating times and high injury risk. With those hours, Olympic is feasible. If your goal is 70.3 and you only have 5 h/week, plan to first prep an Olympic (12-16 weeks), race it, and then negotiate 8-10 h/week in your personal/professional life for 70.3.

Q: Is race-day nutrition really that specific?

Critical. Carbs: 60-90 g/h on bike, 30-60 g/h on run (stomach tolerates less running due to impact). Salts: 500-1000 mg sodium/h in heat or long events. Hydration: 500-750 ml/h temperate, 1000-1500 ml/h heat. And rule number one: nothing new on race day . Every product (gel, drink, bar) must have been tested in long training sessions.

Q: Do I need a tri bike or is a road bike enough?

Road bike with clip-on aerobars is perfectly fine for Sprint and Olympic. For 70.3 and Ironman, a specific tri/TT bike saves 20-40 W at race speed (15-25 minutes on a 90 km loop). The upgrade is worth it for podium-chasers or athletes racing multiple 70.3/Ironman. To participate and enjoy, a road bike with clips + basic aero helmet is enough.

Sprint, Olympic, 70.3 or Ironman. EntrenAI structures the three disciplines (swim, bike, run) into an integrated plan, manages cross-discipline interference, validates that the distance is realistic for your level and applies the right peaking for your goal date.

Updated September 14, 2026

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100+ athletes

thousands of plans generated

What is an AI-built triathlon training plan?

Triathlon is a multi-discipline event with four standardized distances:

Sprint — 750 m swim + 20 km bike + 5 km run (1-1:30 h for amateurs)
Olympic / Standard — 1500 m + 40 km + 10 km (2-3 h)
70.3 / Half Ironman — 1900 m + 90 km + 21.1 km (5-7 h)
Ironman — 3800 m + 180 km + 42.2 km (10-15 h)

Each distance demands a completely different plan. Sprint and Olympic resemble "three short workouts per week per discipline"; 70.3 and Ironman require specific blocks with long sessions in each discipline and total volume that can hit 15-20 hours per week in load blocks.

Three triathlon-specific factors the plan must manage:

Cross-discipline interference (Hickson effect, 1980). Doing heavy strength alongside endurance compromises both; running 90 minutes one day and swimming the next with leg DOMS is counterproductive. EntrenAI distributes sessions respecting 24-48 h separation between disciplines that share neuromuscular stimulus.
Run-after-bike hinge (brick). The last 20 % of the run split in triathlon happens with pre-fatigued legs. Without specific "brick" sessions (consecutive bike-run), race day brings muscular collapse. EntrenAI schedules at least 1 brick per week in load blocks.
Strict safety restrictions. The data is unambiguous: 66 % of triathlon deaths happen during the swim segment, mostly in open water, and almost all in athletes with limited swimming experience. For Sprint, the plan requires that you can swim 400 m continuous before starting the specific block. For Ironman, it requires a completed half marathon + 12 months aerobic base + 25 km/week running + a previous Half Ironman.

The distances, side by side

Same engine, three different races: the volume, the brick session and how much the bike matters all change. Pick yours and you will see the times per leg, the transition and the split of hours.

Distance	Weeks	Hours/week	Long session	Bricks	Who for
Sprint	12	6-10	2 h bike	Every 2 weeks	First triathlon or a better time
Olympic	14	7-12	3 h bike	Every 2 weeks	You have done a sprint
70.3	16	9-14	4.5 h bike	Weekly in the specific block	12 months of base in all three

How the plan works

Your AI-generated plan

1. Distance validation. In the onboarding questionnaire, EntrenAI validates whether your goal is realistic for your level:

Sprint: you need to swim 400 m continuously without stopping. Without that base, the plan first suggests an 8-12 week swimming program.
Olympic: requires a completed Sprint or equivalent aerobic base (3-4 months training the three disciplines).
70.3: requires a completed Olympic or equivalent (6+ months base, comfortable 1500 m swim, 60+ km/week cycling).
Ironman: requires a completed Half Ironman, 12+ months aerobic base, completed half marathon, sustained 25 km/week running, 100+ km/week cycling in load blocks.

Asking for a distance you don't have the base for, the system blocks you or suggests an intermediate. This is for safety — not technical difficulty.

2. Discipline distribution. Approximately:

Swim: 20-25 % of total time (the shortest distance discipline but most technical)
Bike: 45-55 % (highest absolute volume)
Run: 25-30 % (high neuromuscular cost, can't accumulate as much volume without injury)
Strength: 5-10 % (short 30-45 min sessions, complementary)

3. Total weekly volume by distance and level:

Sprint beginner: 4-6 h/week
Sprint intermediate/advanced: 6-9 h/week
Olympic: 7-12 h/week
70.3: 10-16 h/week (in load blocks)
Ironman: 12-22 h/week (in load blocks)

4. Block periodization. Typical plan for a goal date:

Aerobic base block (4-8 weeks): focus on Z1-Z2 volume on bike and run, technique + aerobic base in swimming. No hard intervals.
Build block (4-6 weeks): sweet spot in cycling, tempo and threshold in running, threshold in swimming appear. Regular brick sessions (bike→run).
Specific block (4-6 weeks): goal distance simulations at intensities close to race pace. Open water mandatory if the event is open water.
Taper / peaking (1-3 weeks depending on distance): -50 % volume, intensity held. Expected race day improvement: 2-7 % (Travis, 2020).

5. Brick sessions. Essential. Consecutive bike-run or swim-bike with no significant rest:

Standard bike-run brick: 60-90 min bike + 15-30 min transition run
Long brick (70.3/Ironman): 3-4 h bike + 40-60 min run with last 15-20 min at goal pace
Swim-bike: less common since swim-to-bike transition is less neuromuscularly demanding

6. Fatigue management. More critical than in single-sport contexts. Three disciplines accumulate muscular, joint and systemic fatigue in compound fashion. EntrenAI calculates your daily readiness score and, when it drops, swaps the most demanding session for an easier one (a long run becomes mid-Z2, a swim threshold set becomes EN2). Deloads happen every 3 weeks (1 in 4) instead of every 4 (single-sport).

The transition, drawn: what you practise every two weeks

A 3-minute T1 is 2 minutes given away. The plan includes a transition session every two weeks with the bike on a real rack; this is the order you rehearse.

Leave the water walking fast, not running
Wetsuit down to the waist as you move
Helmet BEFORE touching the bike
Run with the bike by the saddle to the mount line

Dismount before the line, never on it
Rack the bike; helmet off ONLY afterwards
Elastic laces: no sitting down
The first 500 m slower than the body asks for

Who is this plan for?

Four main profiles:

First Sprint triathlon. 12-16 week plan. 4-5 sessions/week, 5-7 total hours. Mandatory base: swim 400 m without stopping before starting. Focus on learning T1 (swim-bike) and T2 (bike-run) transitions, gear setup, simulating with bottle on the bike. Manageable training distances: 1000-1500 m swim, 40-60 km bike/week, 15-25 km run/week.
Improve my Olympic. 16-20 week plan. 5-6 sessions/week, 8-12 total hours. Zone-based structure appears: cycling sweet spot, swim T-pace, running VO2max intervals. 1-2 bricks/week. Typical volume: 2 swim sessions (4000-6000 m), 2-3 bike (100-150 km), 3 run (30-50 km).
First 70.3 / Half Ironman. 16-24 week plan. 5-7 sessions/week, 10-16 hours. Load blocks with long sessions (long run 90 min, long ride 4 h, long swim 2500 m). Weekly long brick (3 h bike + 45 min run). Open water mandatory in last 6-8 weeks. 70.3 simulation test 4 weeks before the event.
Ironman. 20-32 week plan. 6-8 sessions/week, 12-22 hours in load blocks. Very high volume: long run up to 30 km, long ride up to 6 h, long swim up to 4000 m. Massive brick every 2 weeks (4-5 h bike + 1 h run). Three long simulations at 6, 4 and 2 weeks from event. The plan requires a completed Half Ironman and prior validation of 12 months of base.

Coming from a single discipline (running or cycling)? EntrenAI prioritizes the first 2 months on learning to swim (the most technical discipline and where most can be improved). Never competed? It recommends starting with Sprint regardless of your aerobic base — transition complexity, nutrition and competition stress are new variables only learned by competing.

Sample plan

Your first weeks, in detail

Week 8

Olympic intermediate — peak load week of build block

Day	Session type	Detail	Duration
Monday	Swim threshold	Warm-up 600 m + main: 8×100 m at T-pace (1:35/100 m) with 20s rest + 4×200 m at EN2 (1:40/100 m) with 30s rest + 200 m cool-down. Total: 2200 m. Low cardio, technique focus.	60 min
Tuesday	Run tempo	15 min Z1 warm-up + 25 min in Tempo zone (~85 % VDOT) + 10 min cool-down. Cadence and breathing focus.	55 min
Wednesday	Bike sweet spot	15 min Z2 warm-up + 3×15 min @ 90 % FTP with 5 min Z1 rest + 10 min cool-down. Cadence 85-90 rpm. Key bike session of the week.	85 min
Thursday	Swim aerobic + drills	Warm-up 400 m + 4×100 m drills + 5×300 m at EN2 (1:40/100 m) with 30s rest + 200 m cool-down. Total: 2300 m. Comfortable aerobic volume.	60 min
Friday	Run VO2max intervals	15 min Z1 warm-up + 6×800 m at Interval pace (95 % VDOT) with 200 m jog recovery + 10 min cool-down.	55 min
Saturday	Brick: long bike + short run	Bike 2 h Z2 with 2×15 min @ Sweet Spot intercalated + fast transition (shoe change, no eating stop) + Run 25 min Z2-Z3 (first 5 min feel terrible, then stabilize). Total: 2:30 h. Block key session.	150 min
Sunday	Long run	12 km Z2 (~70 % VDOT). Last segment in race goal zone (low Z3). Hydrate every 30 min, gel from 60 min.	75 min

Week 14

70.3 — specific block, 4 weeks from event (T-pace 1:30/100 m, FTP 250 W, VDOT 50)

Day	Session type	Detail	Duration
Monday	Open water swim simulation	In pool without touching wall: warm-up 800 m + 2500 m continuous at EN2 (1:35/100 m) + 200 m cool-down. Total: 3500 m. Sighting every 6 strokes.	70 min
Tuesday	Mid tempo run	15 min warm-up + 35 min Tempo (~85 % VDOT) + 10 min cool-down. Hold constant cadence.	65 min
Wednesday	Bike threshold	20 min warm-up + 2×20 min @ 95 % FTP with 8 min Z1 rest + 10 min cool-down.	85 min
Thursday	Swim speed + run recovery	Morning: pool 800 m warm-up + 12×50 m at SP1 (1:25/100 m) with 30s rest + 200 m cool-down. Total: 1800 m, 50 min. Afternoon: 30 min very easy Z1-Z2 run (recovery) + mobility.	85 min total
Friday	Rest or light cross-training	Full rest or 30 min Z1 bike. Recovery + stretching + mobility.	—
Saturday	Massive brick: reduced 70.3 simulation	Bike 3.5 h with 30 min @ Sweet Spot + 60 min @ Z2 + 30 min @ Sweet Spot + 1 h Z2 → transition → Run 50 min with 30 min in race goal zone (low Z3) + 20 min cool-down. Hydration and nutrition SIMULATING THE RACE exactly. Total: 4:20 h.	260 min
Sunday	Active recovery + easy swim	Morning: 1500 m swim at EN1 (1:40/100 m) very easy, focus on feel. Afternoon: 30 min outdoor walk.	60 min

These examples are real extracts from the EntrenAI planning engine. Your personal plan adjusts to your level, equipment and availability.

Equipment needed

EntrenAI automatically substitutes any exercise if you don’t have the gear.

Road or triathlon bike with clip-on aerobars (minimum for Sprint, important for 70.3+)
Aero helmet optional (important for 70.3 and Ironman, 20-40 W savings at race speed)
Wetsuit (required in waters <22°C; in warm water, use thin suit or skin)
Tri suit / triathlon onesie (swim, ride and run in the same suit)
Open water goggles (wide field of view, anti-fog)
Bike shoes with SPD-SL or similar cleats + lightweight running shoes (for T2, fast-transition footwear)
Multisport waterproof watch (Garmin Forerunner 945+, Garmin Fenix, Apple Watch Ultra)
Bottles, gels, salts, elastic laces for shoes (for faster transitions)

Common mistakes

What most people get wrong (and how to avoid it)

1
Underestimating the swim
It's the highest-risk discipline (66 % of deaths happen there) and a bad day there compromises the rest of the triathlon. Many people with strong bike and run base assume swimming 'will work itself out'. It won't: poor swimming gets you to T1 with elevated heart rate, accumulated lactate and no nutrition. The first 8-12 weeks have a high swim share. And whenever the event is open water, 3-5 specific open water sessions are mandatory.
2
Disrespecting distance restrictions
EntrenAI validates your level against the goal distance. Never run a half marathon and asking for an Ironman? The system blocks it. Not capricious: the injury-and-DNF rate in triathletes who skip distances exceeds 60 %. With 6 months of triathlon training, your next step is Olympic, not 70.3. After a 70.3, wait 12-18 months before Ironman.
3
Skipping brick sessions
80 % of amateur triathletes 'don't have time' for a weekly brick. And all suffer muscular collapse on the second leg of the run. The first 10-15 minutes running after biking are a unique physiological sensation ('heavy' legs, vasoconstriction shifts, etc.) only trained with specific sessions. Minimum 1 brick/week in load blocks, 2 in specific block.
4
Improvised race-day nutrition
Amateur triathletes show up to 70.3 having never tested a single gel or specific carbohydrate drink in their long sessions. Race day, the stomach rejects the sugar and you're nauseous from hour 3. The rule: **all race nutrition must have been tested in long training sessions**. EntrenAI prescribes simulated nutrition in every massive brick: 60-90 g carbs/h on bike, 30-60 g/h on run, salts in heat.
5
Excessive volume close to the event
The last 10-14 days don't add fitness — they only subtract recovery. The Travis (2020) protocol says: -50 % volume, intensity held with short sessions, last hard session 7 days before. Anxious people who train hard until day -3 arrive exhausted and post worse times than their real fitness. EntrenAI auto-blocks long sessions in the final week.
6
Not rehearsing T1 and T2 transitions
T1 (swim → bike) and T2 (bike → run) are disciplines themselves. In Sprint, losing 60 seconds in T1 can mean the difference between top-10 and top-50. The mechanics (peeling off the wetsuit, foot-on-cleat saddle jump, running shoe change without stopping) train. EntrenAI includes specific transition sessions in the last 4 weeks: 5×T1 with simulated wetsuit + 5×T2 with real shoe change.
7
Ignoring strength deficit
Triathletes are usually thin but weak. Without enough muscle mass, long sessions (especially the long run in Ironman) cause early muscular collapse. 1-2 short strength sessions/week (squat, deadlift, single-leg, core) during base + maintenance in specific block — no more, due to interference, but no less either.

Triathlon plans by goal and level

Frequently asked questions

Sprint unless you have a deep prior base. Sprint teaches you to compete in triathlon, manage transitions and nutrition without long-duration pressure. Coming from running with 5+ years and already swimming 1500 m comfortably? You could start with Olympic, but the first race — Sprint or Olympic — teaches you more about logistics than any training. Starting with 70.3 without a Sprint is suboptimal: it dramatically increases DNF (Did Not Finish) risk.

70.3: 16-24 weeks with a previous Olympic and solid aerobic base (6+ months training triathlon regularly). Otherwise, plan 28-32 weeks. Ironman: 24-32 weeks with a completed Half Ironman and minimum 12 months base. Without that prior base, the recommended plan is to first prep 70.3 (16-24 weeks), race it, then start Ironman 6-12 months later.

Depends on distance and block. Sprint: 5-7 h/week (the entire plan). Olympic: 7-10 h/week (load blocks 10-12 h). 70.3: 8-12 h/week average (load blocks 14-16 h). Ironman: 10-15 h/week average (load blocks 18-22 h). Ironman demands a structured life: 6-7 sessions/week, minimum 1 double session (morning + evening) one day per week.

For beginners and Sprint/Olympic, EntrenAI covers 90 %. For 70.3, the plan is complete but we recommend at least one in-person swim session with a coach to correct technique (the discipline with the largest gain potential). For Ironman, we recommend a human coach if you're racing for category/Kona qualification — a personalized coach can dial in the final 5-10 % no standard plan reaches. To participate and enjoy Ironman, EntrenAI is enough.

Reporting acute joint pain, EntrenAI deactivates the affected discipline and compensates with the other two. Leg injury (tibia, knee, ankle)? The plan reduces run volume and increases swim + bike. Shoulder (swim-related)? Reduce swim, increase bike + run. Missing 2+ consecutive weeks in any discipline triggers a step-back and event date reassessment if realistic. Never race with acute pain: a mismanaged injury ends an event.

Honestly, not recommended. With 4-5 h/week it's very hard to reach 70.3 properly prepared — you'll likely finish but with frustrating times and high injury risk. With those hours, Olympic is feasible. If your goal is 70.3 and you only have 5 h/week, plan to first prep an Olympic (12-16 weeks), race it, and then negotiate 8-10 h/week in your personal/professional life for 70.3.

Critical. Carbs: 60-90 g/h on bike, 30-60 g/h on run (stomach tolerates less running due to impact). Salts: 500-1000 mg sodium/h in heat or long events. Hydration: 500-750 ml/h temperate, 1000-1500 ml/h heat. And rule number one: nothing new on race day. Every product (gel, drink, bar) must have been tested in long training sessions.

Road bike with clip-on aerobars is perfectly fine for Sprint and Olympic. For 70.3 and Ironman, a specific tri/TT bike saves 20-40 W at race speed (15-25 minutes on a 90 km loop). The upgrade is worth it for podium-chasers or athletes racing multiple 70.3/Ironman. To participate and enjoy, a road bike with clips + basic aero helmet is enough.