💧 3 Hydration Strategies for Your First 70.3 Ironman Bike Course

While you're likely focused on the last few training sessions and the gear you'll need, one important aspect is often overlooked–your hydration strategy. When you leave this to race day without a plan, you're doing a disservice to the months of training it took to get here. 

The bike portion of any Ironman event is statistically the longest, and nutrition and hydration becomes critical for surviving the impending half-marathon waiting for you at the end. You can race without being conscious of your hydration until suddenly a loss of 2% body weight due to dehydration can start to reduce your performance by 10-20% (think of the cramping–ouch). 

That could be the difference between a 6-hour Half-Ironman and a 7-hour Half-Ironman.

Three hydration strategies for the bike

The Free Spirit 🌀

Your body is smarter than you think. While it might seem casual, it's backed by science – your body's thirst mechanism is surprisingly accurate at maintaining proper hydration levels (just don't ignore it). Rather than following strict timing, you drink when thirsty and adjust based on how you feel. 

The Setup:

• Two bottles of water on the bike. 

• Stopping at aid stations as needed.

Best for: The triathlete who doesn't overthink and is confident listening to their body.

The Just-in-Time 🛩️

Like fighter jets dumping their auxiliary fuel tanks before a dogfight, this strategy is about keeping your weight low and maximizing speed. Plan on stopping at every aid station for a rolling NASCAR pit stop and tossing any unnecessary weight. 

The Setup:

• One quick-refillable Torpedo or reservoir that's topped up at each aid station throughout the race.

• Sipping to thirst.

• Plan to stretch each refill 15 miles and refill at each of the 3 aid stations.

• Flexibility to take on extra water at aid stations during hot days.

• At a 20mph average speed, expect a new bottle every 45 minutes.

Best for: The triathlete who prefers structure, eliminating guesswork, and minimizing weight during climbs.

The Camel 🐫 

"Two is one, and one is none" is the motto of these pack-mules. One water bottle? Nah. Two water bottles? Nah. Four water bottles? Now we're talking. These prepper athletes are ready to finish the race even if a zombie apocalypse happens while they're out on the bike course. This approach also works if you have a sensitive stomach and want complete control over your nutrition.

The Setup:

• 4 XL bottles, including a reservoir for refilling.

• Sipping to thirst.

• No planned stops except for emergencies or equipment issues.

• Complete nutrition independence (hell yeah 🇺🇸)

Best for: The triathlete with a sensitive stomach, racing in a hot and humid venue, or the anxious type.

The Bottle Line

The goal isn't to match fluid loss ounce for ounce during the race—that's impossible and unnecessary.

Some dehydration is normal and expected during a 70.3. Your Mission is to minimize its negative effects for as long as possible, keeping yourself in that sweet spot where you're still performing at your best.

Test these strategies during your long training rides. The one that feels most natural is likely your best bet. Remember that the 6-hour finish time you're dreaming about depends as much on your hydration strategy as it does on your training.

Now, you'll get there with a hydration strategy that works for you. Good luck out there–try not to break a leg.