Half Ironman 70.3

The Half Ironman: Long Course Excellence

The Half Ironman (70.3 miles total) is where triathlon becomes a true endurance test. This isn't about speed—it's about sustainable power, smart pacing, and flawless execution over 4-6 hours. This plan assumes you've completed an Olympic distance triathlon and are ready for the step up to long course racing.

The Long Course Mindset

Half Ironman racing is fundamentally different from shorter distances. You're no longer racing hard—you're racing smart. Every decision compounds over hours. A bad nutrition choice at mile 20 of the bike will destroy your run. Starting the swim too aggressively will cost you watts on the bike.

Patience is everything: The race is won by steady effort, not heroic surges.

Fueling is non-negotiable: You'll burn 3,000-4,500 calories. Your body can only store about 2,000. Do the math—you must fuel consistently.

The bike sets up the run: You can ride yourself off the bike easily. Discipline on the bike makes or breaks your day.

The Training Framework

Your training will require 10-15 hours per week at peak, with single sessions lasting 3-5 hours. This demands careful time management, recovery prioritization, and family coordination.

Swimming (2-3 sessions/week): Building from 2,500m to 4,000m+ sessions. Focus on endurance, stroke efficiency, and open water confidence. Your goal is to exit the water ready to ride hard.

Cycling (3-4 sessions/week): Progressing to rides of 4-5 hours. You'll develop the muscular endurance to maintain watts in the aero position for 3 hours. Includes tempo work, long steady rides, and brick sessions.

Running (3-4 sessions/week): Building to 35-40 miles per week with long runs reaching 13-16 miles. Focus on running off tired legs with regular brick runs.

The Four Phases

Foundation (Weeks 1-6): Build consistent volume without intensity. Long rides reach 2-2.5 hours, long runs build to 90 minutes. Swimming focuses on technique and endurance. Weekly training time builds from 8 to 12 hours.

Build One (Weeks 7-11): Add quality work. Long rides extend to 3-4 hours with tempo intervals. Run volume peaks at 35 miles/week. Swimming includes threshold sets. Weekly training peaks at 12-14 hours. First serious brick workouts appear.

Build Two (Weeks 12-15): Race-specific work. Long rides reach 4-5 hours at race effort. Brick runs extend to 60-90 minutes. You'll practice race-day nutrition on every long workout. This is your highest training stress.

Peak & Race (Weeks 16-18): Final race-effort workouts in week 16, then a careful two-week taper. Volume drops 50% but you maintain fitness with short, quality efforts. Arrive at race day fresh and confident.

Critical Training Principles

The long ride is sacred: Your 4-5 hour rides teach your body to metabolize fat, your mind to stay focused when tired, and your nutrition strategy to work under stress.

Brick intensity matters: Not all brick runs need to be easy. Include some at race pace to teach your body what half marathon pace feels like off the bike.

Practice everything: Your long workouts are dress rehearsals. Wear race day gear, use race day nutrition, practice your pacing. Learn what works now, not on race day.

Sleep is training: You can't recover from 12-hour training weeks on 6 hours of sleep. Prioritize 8-9 hours nightly during peak training.

Race Week Preparation

Six days out: Last quality workout—30-minute tempo effort in each sport. Nothing long, nothing easy—just a reminder to your body that you're fit.

Three days out: Complete rest or 20 minutes easy swimming. Start carb loading (not overeating, loading).

Race morning: Wake up 3 hours before race start. Eat your practiced breakfast. Sip water consistently until 30 minutes before the start.

Race Day Strategy

Swim (1.9km): Start conservatively. The swim is about positioning for the bike, not winning. Find draft when possible. Smooth is fast. Exit ready to ride hard.

T1: Take your time. Get your nutrition sorted. Make sure everything is where it should be before you leave transition.

Bike (90km): First 30km—settle in, find your watts, start fueling immediately. Middle 40km—steady effort, consistent nutrition every 15 minutes. Final 20km—prepare mentally for the run, keep fueling, maintain power.

T2: Your legs will feel wooden. This is normal. Walk if needed. Get your run shoes on, grab your fuel, start controlled.

Run (21.1km): First 5km—let your legs remember how to run. Don't chase pace, chase effort. Middle 10km—settle into rhythm, maintain nutrition. Final 6km—this is where you empty the tank. You've trained for this. Finish strong.

The 70.3 Truth

This race will test everything you've built—your endurance, your discipline, your mental toughness, your nutritional strategy. There will be dark moments, usually between miles 50-60 when your mind starts asking uncomfortable questions. Remember: you've done the work. Trust your training. Stay present. Keep moving forward.

The finish line of a Half Ironman feels different than any other race. It's earned through months of early mornings, long weekends, and unwavering commitment. When you cross it, you'll understand why people call themselves Ironman athletes. Because you are one.