01·Course Characteristics
A scenic single-loop peninsula course in Aichi Prefecture defined by intense humidity, heavy coastal headwinds, and a flat but completely unshaded point-to-point run.
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02·Course by Section
A calm single-loop swim in the highly protected waters of Atsumi Bay. Athletes will experience minimal ocean swells, though coastal winds can introduce minor surface chop.
A fast, scenic loop showcasing beautiful shorelines with high-quality smooth asphalt. It features sharp U-turns near the wind power plant and a short but notoriously steep 11% ramp near Cape Irago.
An extremely flat point-to-point run through local parks and coastal industrial zones, crossing the Mikawa Port Great Bridge. Shade is virtually non-existent along wide dockside roads, leaving you fully exposed to the sun and coastal winds.
03·AVG beginners' Training Timeline
This 16-week progression is designed to build the specific physical capacities required to handle Aichi's humid conditions and coastal winds. By starting with a strong aerobic foundation, building strength for the 11% ramp, and ending with heat-acclimation runs, you will arrive at Toyohashi fully prepared to conquer the elements.
Aerobic Base & Adaptability
Develop early cardiovascular resilience and high-cadence swim consistency.
Strength & Wind Resistance
Build low-cadence climbing power for the steep Cape Irago ramp and sustained aero power for wind.
Heat & Endurance Specifics
Incorporate heat-adaptation runs and target pacing under simulated high-humidity conditions.
Taper & Sharpen
Reduce volume while maintaining brief high-intensity intervals to peak for the humid race day.
Adapts to your fitness, schedule & recovery every week.
Personalize this timeline04·Race-Day Execution
With afternoon humidity reaching 90% and temperatures rising to 28°C, thermal management is key. Pour water over your head and shoulders at every aid station along the unshaded run to drop your core temperature.
Aim for 500-750 ml of sodium-rich fluids per hour on the bike to counter heavy sweat rates in high humidity. Do not skip the early aid stations on the run, as the point-to-point dock roads offer zero shade.
Save your legs on the flat bike loop by pacing conservatively through the heavy coastal winds and dropping into your easiest gear on the 11% Cape Irago ramp. Maintain a steady, controlled rhythm on the flat, exposed run.
A deep-section rear wheel is fast on the flat asphalt, but choose a moderate front wheel depth to handle the peninsula's coastal crosswinds. Book lodging near Toyohashi Station and utilize the official morning shuttles to T1 at Shiroya Beach Park, as transition areas are split 24 km apart.
The average water temperature in Atsumi Bay is around 21°C (69.8°F) in early June, making wetsuits highly recommended and fully legal. The single-loop 1.9 km swim is held in calm, protected waters with no major ocean swells, though wind can sometimes cause minor surface chop.
The 90.1 km single-loop bike course is moderately difficult, featuring a mostly flat and fast profile with a total elevation gain of 500m to 670m. However, you must prepare for heavy wind exposure along the Pacific coast and a short, notoriously steep ramp of up to 11% gradient near Cape Irago. There are also a few technical sections, including sharp U-turns and narrow roads through agricultural villages.
The 21.1 km run is a fast, flat, point-to-point course with under 50m of total elevation gain, with the only notable climb being the Mikawa Port Great Bridge. However, it is highly demanding due to thermal stress, as the wide dockside roads of the Jinno Wharf are almost entirely unshaded. You will be fully exposed to the sun and potential coastal winds in afternoon temperatures reaching up to 28°C (82°F).
With high humidity levels between 75% and 90% and afternoon temperatures approaching 28°C (82°F), a proactive hydration strategy is essential. You should aim to consume 500–750 ml of fluid rich in sodium per hour on the bike to prevent cramping before starting the unshaded run. On-course aid stations will be stocked with water, sports drinks, and gels to support your race.
This race features a split-transition layout, with T1 located at Shiroya Beach Park in Tahara and T2 located at Toyohashi Sports Park, which is roughly 24km away. To manage this logistics setup smoothly, it is highly recommended to book your lodging near Toyohashi Station. From there, you can easily utilize the official event shuttle buses to transport yourself and your gear to the start line on race morning.
Your Personalized Plan
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