Belo Horizonte's wet season runs roughly October to March, heaviest November through January. That covers your entire peak block (Oct 5 – Nov 22) and quite possibly race day itself. Build the adaptation in August and September, while it is still optional — the failure mode is your first treadmill long run being a forced one in November.
Treadmill
- Set 1% incline to offset the missing air resistance. Do not go steeper — incline shifts load onto the soleus and Achilles, the opposite of what you want.
- Expect 15–30 s/km slower at the same heart rate. Indoor heat, humidity and no cooling airflow all push HR up. Because you train to an HR cap, the treadmill self-corrects your pace — let it. This is not lost fitness.
- Genuinely good for the tendon: flat, consistent, no camber, no potholes. Kinder than crowned roads.
- Its one downside: an identical stride thousands of times. Nudge pace or incline slightly every 5–10 minutes rather than locking one speed for an hour.
- Use it for Tuesday and the easy runs; keep Sunday outdoors when you can, for specificity and fuelling practice. If a storm forces the long run indoors, break it into blocks.
- Ramp in now: two or three easy 6–8 km treadmill runs across August and September and it stops being a novelty.
Running in the rain
- Two pairs of shoes on rotation. Soaked shoes need 24h+ to dry; repeatedly running in them causes blisters and accelerates midsole breakdown. Newspaper inside speeds drying — never a heat source.
- Anti-chafe balm — nipples, inner thighs, underarms. Chafing, not cold, is what ruins wet long runs.
- Brimmed cap beats a hood: keeps rain out of your eyes without killing peripheral vision. Technical fabric only, never cotton.
- Longer warm-up. Your Achilles protocol already says never start cold; in cool rain that stops being advice and becomes the rule.
- Wet ground shortens your stride and adds constant slip-correction, loading the calf differently. Expect higher perceived effort at the same pace, and avoid painted lines, metal covers and smooth tile.
- Lightning is a treadmill day, not a judgment call.
- Skip the cold-rain run if the morning Achilles score is 4+. Cold plus a stiff tendon is a bad combination.
When weather breaks the week
With four fixed days against a wet season, treat the days as movable within the week — if Wednesday storms, run Thursday. Protect the clear day on either side of the long run before you protect anything else. Keep the long run and the race separated, and do not make up missed kilometres. Miss a run, let it go.