Inputs
Body weight
70kg
40130
Sweat loss / hour
0.90kg/hr
Net weight loss per hour of activity. 1 kg sweat ≈ 1 L fluid.
0.22.5
LightModerateHeavyElite
Classification: Moderate sweater
How to measure›
- 01. Weigh nude before activity.
- 02. Train at race intensity for a known time (60+ min ideal).
- 03. Track fluid drunk during the session (mL).
- 04. Towel off, weigh nude again.
- 05. Sweat rate (L/hr) = (Δ kg + fluid L) ÷ hours
Session duration
2hrs
Sweat saltiness
Salty crust on cap or stinging eyes mid-effort? Bump up one.
Heat exposure
Carb intensity
Bottle size
Per Bottle
500 mlDose exact. Use a kitchen scale (0.01 g resolution) for the minerals.
Table salt (NaCl)
1.04 g
≈ 1/8 tsp
Potassium chloride (KCl)
0.25 g
≈ 1/8 tsp
Magnesium citrate (Calm)
0.13 g
≈ 1/8 tsp
Dextrose (glucose)
44.4 g
≈ 3.7 tbsp
Water
500 ml
Delivers per bottle
Na
410 mg
K
133 mg
Mg
10 mg
CHO
44.4 g
Per hour
1.4
bottles to drink
Fluid675 ml
Na553 mg
CHO60 g
Session total
3
bottles to prep
Fluid1.4 L
Na1106 mg
CHO120 g
!
Sanity check. Sodium concentration of this formula: 819 mg/L. Carb concentration: 8.9% (target 4–8%). Drink to thirst — do not force-fluid past the per-hour target.