How to use
- Enter the inputs.
- Sanity-check the outputs.
- Use the result as a planning anchor, not a promise.
Jump to
Tool
Inputs → outputs
This page is intentionally practical: get numbers first, then read the how-to.
Inputs
- • Bike duration (hh:mm)
- • Run duration (hh:mm)
- • Carbs bike (g/h)
- • Carbs run (g/h)
- • Sodium bike (mg/h) (optional)
- • Sodium run (mg/h) (optional)
- • Fluid bike (ml/h) (optional)
- • Fluid run (ml/h) (optional)
Outputs
- • Total carbs (g)
- • Total sodium (mg)
- • Total fluid (ml)
Export
Print or share the tool
Useful outputs beat generic SEO copy. Print a PDF or share this page before race week.
Tip: print or save as PDF for race week.
Example presets
Prefill with a realistic scenario
Pick an example to prefill the calculator, then tweak inputs for your own training week.
Loading 70.3 fueling planner…
Quick answers
The 60-second version
Snippet-ready answers to common questions. Use the calculator above for the numbers.
Should I fuel the same on bike and run?
Usually no. The run is higher impact and many athletes tolerate less. Practice bricks to find your run target.
How early should I start fueling?
Start early on the bike, then keep it steady. On the run, use a simpler, tolerable schedule.
Do I need to drink to thirst?
Thirst is useful but not perfect in heat. Practice a plan and adjust to conditions; avoid extremes.
Assumptions
What this tool assumes
- • Hourly targets are based on what you tolerate in training (not a prescription).
- • Bike fueling is typically easier than run fueling — don’t assume equal tolerance.
Limitations
What can break it
- • Does not replace professional nutrition guidance for medical conditions.
- • Heat and sweat rate can change fluid/sodium needs dramatically.
Related
Use this with a plan
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FAQs
Should I fuel the same on bike and run?
Usually no. The run is higher impact and many athletes tolerate less. Practice bricks to find your run target.
How early should I start fueling?
Start early on the bike, then keep it steady. On the run, use a simpler, tolerable schedule.
Do I need to drink to thirst?
Thirst is useful but not perfect in heat. Practice a plan and adjust to conditions; avoid extremes.
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