Leadville Trail 100 Run
Race across the sky. 100 miles between 9,200 and 12,600 feet of elevation. Hope Pass twice. 30 hour cutoff.
Leadville is cold and high, but sodium needs do not drop the way the temperature suggests. Altitude adds 1 to 2 liters of respiratory fluid loss over the race, so add 200 to 300 mL of fluid per hour at elevation and plan 5 to 10 percent more sodium than a sea-level estimate. The aid stations list no broth, so carry your own sodium for the overnight miles.
Leadville 100 Fueling Plan
For a 165 lb athlete finishing Leadville 100 in about 25 hr, plan roughly 60 g of carbs, 550 mg of sodium (750 mg for a salty sweater) and 600 ml of fluid per hour. That is about 1,500 g of carbs and 13,800 mg of sodium across the race.
| Finish time | Carbs | Sodium | Fluid |
|---|---|---|---|
| Front of field18 hr | 60 g/hr1,080 g total | 550 mg/hrsalty sweater 750 mg | 600 ml/hr10.8 L total |
| Mid-pack25 hr | 60 g/hr1,500 g total | 550 mg/hrsalty sweater 750 mg | 600 ml/hr15 L total |
| Back of pack29 hr 30 min | 60 g/hr1,770 g total | 550 mg/hrsalty sweater 750 mg | 600 ml/hr17.7 L total |
Computed by the free sodium and carb calculators for a 165 lb athlete in mild conditions. Fluid is a planning figure for what to carry, not a drinking schedule: on the day, drink to thirst. Your own numbers move with body weight and sweat rate.
Where The Sodium Math Bends
Leadville 100 starts at 10,144 ft, tops out at 12,537 ft at Hope Pass (mile 46.1) and finishes at 10,144 ft. Cramping tends to cluster on the long climbs and the descents that follow them.
- Mile 0, Start, Leadville, 10,144 ft
- Mile 10.6, Carter Summit, 10,699 ft
- Mile 20.5, Turquoise Lake Dam, 9,896 ft
- Mile 26, Outward Bound, 9,538 ft
- Mile 31.8, Half Pipe, 9,802 ft
- Mile 40.3, Twin Lakes, 9,255 ft
- Mile 46.1, Hope Pass, 12,537 ft
- Mile 52.2, Winfield, 10,232 ft
- Mile 58.3, Hope Pass, inbound, 12,537 ft
- Mile 64, Twin Lakes, inbound, 9,240 ft
- Mile 78.3, Outward Bound, inbound, 9,534 ft
- Mile 84.2, Turquoise Lake Dam, inbound, 9,930 ft
- Mile 99.7, Finish, 10,144 ft
| Climb | Miles | Gain | Avg grade |
|---|---|---|---|
| Carter Summit, outbound | 5.6 to 10.2 | 948 ft | 3.9% |
| Hope Pass, north side | 41.8 to 46.1 | 3,332 ft | 14.7% |
| Hope Pass, south side (inbound) | 56 to 58.3 | 2,450 ft | 20.2% |
| Colorado Trail out of Twin Lakes (inbound) | 63.5 to 67.6 | 1,406 ft | 6.5% |
| Turquoise Lake roads (inbound) | 85.4 to 89.4 | 880 ft | 4.2% |
What's On Course
Aid stations stock water, Neversecond gels and high-carbohydrate drink mix, Skratch hydration, bars and chews, Pickle Juice products, bananas, figs, pretzels, chips and Coke; no broth is listed. On the 2026 course, rerouted around the Willow Fire, the last aid was Turquoise Lake Dam at mile 84.2, leaving 15.5 miles to the finish with none. Crews may meet runners only at Outward Bound, the Pipeline crew spot and Twin Lakes. The organizer has not yet published the 2027 course.
| Mile | Station | Cutoff | Carry in |
|---|---|---|---|
| 10.6 | Carter SummitMini aid: limited drinks and food | 160 g carbs, 1,450 mg sodium1,600 ml fluid over 10.6 mi | |
| 20.5 | Turquoise Lake DamFull aid; drop bags | 10:15 AM Sat | 150 g carbs, 1,350 mg sodium1,500 ml fluid over 9.9 mi |
| 26 | Outward BoundFull aid; drop bags; crew access | 11:15 AM Sat | 85 g carbs, 750 mg sodium850 ml fluid over 5.5 mi |
| 31.8 | Half PipeFull aid; drop bags | 12:15 PM Sat | 85 g carbs, 800 mg sodium850 ml fluid over 5.8 mi |
| 40.3 | Twin Lakes VillageFull aid; drop bags; crew access by shuttle | 2:15 PM Sat | 125 g carbs, 1,150 mg sodium1,250 ml fluid over 8.5 mi |
| 45.4 | Hope PassFull aid | 4:45 PM Sat | 75 g carbs, 700 mg sodium750 ml fluid over 5.1 mi |
| 52.2 | Winfield turnaroundFull aid; drop bags | 6:50 PM Sat | 100 g carbs, 950 mg sodium1,000 ml fluid over 6.8 mi |
| 59 | Hope Pass, inboundFull aid | 100 g carbs, 950 mg sodium1,000 ml fluid over 6.8 mi | |
| 64 | Twin Lakes Village, inboundFull aid; drop bags; crew access by shuttle; pacers may join | 11:00 PM Sat | 75 g carbs, 700 mg sodium750 ml fluid over 5 mi |
| 72.6 | Half Pipe, inboundFull aid; drop bags | 2:00 AM Sun | 130 g carbs, 1,200 mg sodium1,300 ml fluid over 8.6 mi |
| 78.3 | Outward Bound, inboundFull aid; drop bags; crew access | 3:45 AM Sun | 85 g carbs, 800 mg sodium850 ml fluid over 5.7 mi |
| 84.2 | Turquoise Lake Dam, inboundFull aid; drop bags; last aid before the finish | 5:30 AM Sun | 90 g carbs, 800 mg sodium900 ml fluid over 5.9 mi |
| 99.7 | Finish, Leadville | Under 30 hr (big buckle under 25 hr) | 235 g carbs, 2,150 mg sodium2,350 ml fluid over 15.5 mi |
Carry in is what a mid-pack average sweater (25 hr finish) uses between the previous station and this one at an even pace. Climbs take longer than their share of the distance, so carry more into a climbing section.
Source: Leadville Trail 100 Run race page, 2026 Willow Fire reroute, 2026
35-78°F · low humidity
Climate
mild
Humidity
low
Cutoff
30 hours
10-yr avg high
67°F
10-yr avg low
39°F
Record high / low
76° / 34°F
Years with rain
50%
The Cumulative Deficit Window
Leadville is dry, cold at altitude, and long enough that sodium deficit compounds through the night. The altitude-driven hyperventilation increases respiratory water loss, often 1-2 liters extra over a full race. Sweat sodium concentration drops slightly with heat acclimation, but most Leadville athletes do not heat-acclimate (they elevation-acclimate instead), so the salty-sweater profile shows up under-recognized. The two Hope Pass climbs (to the summit at about mile 46 outbound and mile 58 inbound on the 2026 course) are the cramping windows; the overnight cold around 1-4 AM is the hyponatremia window for athletes who keep drinking but stop eating salty calories.
Key Considerations
- Altitude increases respiratory water loss beyond sweat loss; add 200-300 mL fluid per hour at elevation versus what the calculator suggests.
- Sodium needs do not drop as much as temperature suggests; cold-weather underfueling sodium is the most common Leadville crewing mistake.
- The overnight stretch between Twin Lakes and Outward Bound is the hyponatremia window. Switch from plain water to electrolyte drinks after Twin Lakes inbound.
- The aid stations list Pickle Juice, chips and pretzels but no broth, so carry your own sodium for the night. On the 2026 course the last aid was at mile 84.2, 15.5 miles from the finish.
Who Finishes, And How Fast
Leadville Trail 100 Run 2026 results
Men winner · 2026
Adrian Macdonald
15:47:23Willow Fire reroute
Women winner · 2026
McKendree Hickory
19:39:12debut, 10th overall
Finish rate ~50%
Free Tools, Pre-Filled For Leadville 100
Tap any tool. We pre-load your event, climate, and sweat profile. Adjust your weight and finish target and the plan generates instantly.
Sodium plan
Per-hour sodium and fluid targets for Leadville 100 conditions.
Carb fueling
Hourly carb targets and a fuel menu calibrated to your weight and the Leadville 100 duration.
Heat protocol
10-14 day adaptation plan if you're racing into a warmer climate.
Hydration audit
Weigh-in test that converts a 60-minute training session into a measured sweat rate.
Caffeine timing
Pre-race dose, mid-race top-ups, and race-week taper protocol for Leadville 100 timing.
Dig Into The Science
Beetroot Powder and Altitude Training: The Science
Dietary nitrate improves oxygen economy at altitude, where reduced partial pressure amplifies every performance deficit.
Stop Leg Cramps: Supplement Protocol & Risk Calculator
Leg cramps have two causes: electrolyte depletion and neuromuscular fatigue. Score yours with the free calculator, then load the 5 supplements that fix both.
Potassium for Endurance Athletes: Cramps and Targets
Potassium drives muscle contraction, fluid balance, and nerve signaling. Endurance athletes lose 100 to 300 mg per hour in sweat.
Your Leadville 100 Plan,
Built From Real Data.
Pro unlocks a per-leg sodium, fluid, and carb schedule keyed to the actual course: Leadville to Twin Lakes, Twin Lakes to Hope Pass, and Hope Pass to the finish, with a climb-specific dose bump for the Hope Pass ascent.
- Your sweat rate, from a weigh-in test or your best estimate
- Per-leg sodium, fluid, and carb schedule keyed to the course profile
- Branded, printable PDF
- Post-race feedback capture so the next plan is sharper
Per race
Every race
Unlimited race plans today. Strava connection and the multi-event calendar are still in development.
Free tools stay free, always
About Leadville 100
Does altitude change my sodium needs?
Indirectly yes. Altitude does not change your sweat sodium concentration, but it increases total fluid loss (respiratory plus sweat), which means more sodium leaves the body even at the same intensity. Plan 5-10% higher than your calculator output for events above 8,000 feet.
How much fluid per hour should I take at Leadville?
Most finishers fall in the 18-24 oz per hour range when moving. Increase to 24-28 oz on the Hope Pass climbs where workload is highest. Drop to 15-18 oz overnight when ambient temperature is in the 30s.
When do most Leadville cramping incidents happen?
Two windows. First, the descent off Hope Pass toward Winfield, when sodium intake on the climb fell short. Second, the late climbs after mile 80 (Powerline and Sugarloaf on the standard course, the Turquoise Lake roads to mile 89 on the 2026 reroute), when the cumulative deficit catches up. Pre-dose 600 mg sodium at the base of each major climb.