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Running · HartbeespoortOm Die Dam Ultra Marathon training plan
The Om Die Dam Ultra Marathon is 50 km in Hartbeespoort, next held on 13 March 2027. A 21-week block for it starts on Monday 19 October 2026, and at 1 160 m the race-day paces have to come down for anybody who trains at the coast. For a club athlete on 45 km a week with a 1:55 half marathon behind them, the plan expects a finish around 4:53:31.
Build my own Om Die Dam 50 km plan — freeThe date, distance and altitude are filled in for you. See the whole block free before you unlock it.
The race
| Distance | 50 km |
|---|---|
| Where | Hartbeespoort |
| Altitude | 1 160 m |
| Next edition | Saturday, 13 March 2027 (expected — not yet confirmed with the organiser) |
Not yet confirmed by the organiser, so it is shown as expected rather than fact. Last checked 2026-09-11. Check the official entry page before booking anything.
Your calendar to race day
A 21-week block, laid out against the 13 March 2027 race date:
| Block starts | Monday 19 October 2026 — week 1 |
|---|---|
| Harder sessions arrive | Monday 14 December 2026 — week 9 |
| Peak weeks begin | Monday 8 February 2027 — week 17 |
| Taper begins | Monday 22 February 2027 — week 19 |
| Race day | Saturday, 13 March 2027 |
Volume rises no more than 10% a week and every fourth week is lighter. The full week-by-week table for this distance is on the 16-week 50 km ultra plan page.
Race-day targets
| The race | 5:41/km for the first third, then hold or lift Start slower than feels right. On a long day the race does not begin until two thirds in, and every place lost in the first hour comes back. Nothing lost in the last hour ever does. |
|---|---|
| Expected finish | 4:53:31 — Run 4:53:31 |
Worked out for a club athlete on 45 km a week with a 1:55 half marathon behind them. Yours come from your own time trial.
Predict your Om Die Dam 50 km time
Filled in with an example. Type your own numbers and it recalculates.
| Distance | 50 km |
|---|---|
| Race altitude | 1 160 m |
| Even-pace halfway | 2:21:24 |
| Your fitness (VDOT) | 38.3 |
Flat-course physiology plus an altitude correction. Hills, heat and pacing are not modelled, and past the marathon the time follows how real ultra fields finish: allow for the course.
The full predictor for this race →
The altitude, for or against you
At 1 160 m, a coastal athlete who races to their training pace will blow up. Somebody who trains high arrives adapted. Steady race pace for a club athlete on 45 km a week with a 1:55 half marathon behind them:
| Where you train | Pace in training · pace on race day |
|---|---|
| Training at the coast | 5:41/km · 5:56/km |
| Training in Johannesburg (1 753 m) | 6:10/km · 5:56/km |
Roughly 2% per 300 m above 500 m, corrected only for the difference between where you train and where you race. A planning estimate — individuals vary.
Common questions
When should I start training for the Om Die Dam 50 km?
For a 21-week block, on Monday 19 October 2026. Starting later still works — the plan shortens the base phase to fit — but inside about six weeks the block stops being able to add fitness and becomes about arriving healthy.
What finish time should I expect at the Om Die Dam 50 km?
For a club athlete on 45 km a week with a 1:55 half marathon behind them, about 4:53:31. Past the marathon this follows how real Comrades and Two Oceans fields finish (about 2.5× a marathon for Comrades), not the pure fitness model, which is far too optimistic that far out. Heat, fuelling and pacing the first half still decide the day. Your own prediction comes from your own time trial.
Does altitude matter at the Om Die Dam 50 km?
Yes. At 1 160 m the plan slows race pace by about 4.4% for an athlete who trains at the coast. Somebody who trains in Johannesburg is already adapted and needs a much smaller adjustment.