01·Course Characteristics
A fast downstream swim gives way to a relentless, wind-swept bike and a scorching, shade-free run. Jacksonville tests your thermal tolerance and constant pedaling endurance rather than your climbing legs.
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02·Course by Section
A point-to-point downstream swim starting at Metropolitan Park and ending near Memorial Park. Guided by an incoming tide, athletes experience exceptionally fast times but must carefully navigate river currents around massive bridge pilings.
A flat, two-loop course featuring early technical 90-degree turns and the brief but steep Acosta Bridge climb. The remainder of the course demands constant, uninterrupted pedaling along exposed, wind-swept highways with rough asphalt.
A three-loop marathon traversing historic Riverside, concrete riverwalks, and three taxing crossings of the Main Street Bridge. The course is highly exposed to the intense Florida sun with virtually zero shade during the hottest afternoon hours.
03·AVG beginners' Training Timeline
This 28-week plan is engineered to prepare you for Jacksonville's unique challenges. We front-load foundational aerobic volume before transitioning to specific flat-line pedaling endurance, followed by targeted heat acclimation and joint preparation for the concrete run, culminating in a precision taper.
Aerobic Foundation
Build a robust aerobic base and initial durability to handle the high-volume training of a full-distance event.
Relentless Pedaling Endurance
Develop core strength and muscular endurance for continuous, aero-position pedaling with zero coasting.
Heat & Specific Build
Integrate heat adaptation protocols and long, concrete-simulating runs to prepare for the Florida climate.
Taper & Sharpen
Reduce volume to shed cumulative fatigue while maintaining high intensity to peak for race day.
Adapts to your fitness, schedule & recovery every week.
Personalize this timeline04·Race-Day Execution
With afternoon humidity averaging 76 percent and temperatures peaking at 35°C, prioritize pre-cooling at every single aid station. Utilize ice, cold sponges, and cold water over your head and torso to manage your rising core temperature from the very start of the run.
Carb-load thoroughly with 8 to 10 g of carbohydrates per kg of body weight for 48 hours pre-race. On the course, target 600 to 1,000 mL of fluid and 800 to 1,200 mg of sodium per hour to combat the elevated sweat rates caused by oppressive Florida humidity.
Avoid over-biking on the deceptively flat 180 km bike course, which offers no natural rest breaks and demands constant pedaling. Run a highly conservative pace during the first 5 to 10 km of the marathon to prevent early heat illness.
Securely mount all nutrition bottles on your bike to prevent them from ejecting on rough highway pavement and sharp turns. Use official race shuttles to travel the 1.5 to 2 miles from the transition zone at Memorial Park to the point-to-point swim start at Metropolitan Park.
The swim takes place in the St. Johns River with an average water temperature of approximately 67°F (19.4°C), making it wetsuit legal. Because this point-to-point, 2.4-mile course runs downstream and is aided by an incoming tide, you can expect exceptionally fast swim times. However, you must stay alert and navigate carefully around the currents near the Main Street, Acosta, and Fuller Warren bridge pilings.
The 112-mile bike course is flat and fast with a total elevation gain of 873 to 1,604 feet, but it is deceptively taxing. Aside from a 5 percent grade climb over the Acosta Bridge in the first mile, you will face flat, exposed stretches that demand constant pedaling with no opportunities to coast. Additionally, you must prepare for rough asphalt on Philips Highway, technical 90-degree turns, and strong headwinds or crosswinds along Nocatee Parkway and the A1A Scenic Highway.
You should prepare for high heat and oppressive humidity, with morning lows of 71°F (21.5°C) rising to a median afternoon high of 87°F (30.5°C) and peaks up to 95°F (35°C). The average humidity of 76 percent severely impairs sweat evaporation, which significantly raises your risk of dehydration and heat illness. The run course is especially challenging as it is almost entirely exposed to the intense Florida sun with virtually no shade.
Due to the extreme heat and humidity, your sweat rate can increase by 15 to 25 percent, meaning you should target 600 to 1,000 mL (20 to 34 oz) of fluid and 800 to 1,200 mg of sodium per hour. Be sure to securely mount all nutrition bottles on your bike to prevent them from ejecting on the rough pavement and sharp 90-degree turns. On the run, prioritize pre-cooling at every aid station with ice, cold sponges, and water while keeping your pace conservative early on to manage your core temperature.
The run is a rolling, 26.2-mile, three-loop marathon course on paved city streets, sidewalks, and the concrete Riverwalk. You will traverse historic Riverside, downtown Jacksonville, and cross the blue Main Street Bridge three times, which accounts for the course's 301 to 435 feet of elevation gain. While the course offers almost no shade from the intense sun, the multi-loop format provides incredible spectator support, especially near the Riverfront Plaza finish line.
Your Personalized Plan
FE26 builds your plan around your Strava data, your real schedule, and the exact demands of IRONMAN Jacksonville— then adapts every week to how you actually perform.
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