I would offer to share running routes, but I highly doubt anyone reading this will ever be running in Lamezia, where most of my running has occurred. My bestie even made a heart-shaped route that a few of us ran the morning of my wedding (well, heart shaped if you blur your eyes a lot, but I knew what she meant!). As for my running in other Italian cities, I haven't run anything someone else wouldn't figure out.
Anyway, here's some Italian running vocab!
Runner: Corridore (m); Corridortrice (f) (but most women just use the masculine, much like with jobs (such as lawyer or doctor))
Sprinter: Velocista (m.); Scattista (m.)
Harrier/off-road runner: Corridore campestre (m.)
Road runner (person, not the animal): Podista (but this can also mean walker, or race walker)
Road runner (the animal, just for kicks): Corridore delle strade (literally, runner of the streets, but it means the animal, Geococcyx californianus, uccello della famiglia dei cuculidi (bird of the family cuculidi))
Track (the sport): Corsa su pista
Track meet: Gara di atletica leggera
Track and field: Gare di atletica
Distance runner: Corridore di lunga distanza
Marathon runner: Maratoneta (m.) (so, il maratoneta)
Jogger: Persona chi/che fa jogging OR Persona chi/che fa footing
Runner's high: Sballo del corridor (m.)
Track (the place where we run ovals repeatedly): Pista (or Pista da corsa) (see above, track (the sport) translates roughly as "running on a track")
Track/path of a race: Percorso
To run: Correre (see translations below)
To run (to travel or cover a distance): Percorrere (see sample sentence below)
Do not run (at a pool, in case of fire): Non correre
To run a race: Partecipare ad una gara
Race (noun): Gara
Run (noun): Corsa
Runs (noun): Corse -- there's no worry about using this term and having someone thing you mean "the runs" in any bowel sense, there's no translation of that slang as far as I know, to say "the runs" in that sense, your choices are diarrea OR dissenteria; no false friends here!
Warm-ups, tracksuit (clothing): Tuta
Starting line: Linea di partenza
Finish line (if you're emphasizing the line part): Linea del traguardo
Half-marathon: Mezza maratona
Bib: Pettorina (not the same word as is used on a baby, bavaglino)
Stride (as in gait): Falcata
Stride (as in footstep): Passo
To train: Allenarsi
I am (in) training: Sto allenando (same if you're male or female)
To stretch: Allungare OR Fare stretching
To cross-train: Allenare/allenarsi in diverse discipline (somehow, my gut says maybe Italians don't use this expression, maybe they say "cross-train" or their translations of "bike" or "row" or "lift weights" or "swim" or whatever)
To warm up: Riscaldarsi
Warm-up (noun): Riscaldamento
Cool-down (noun): Defaticamento
Sports drink: Bevanda isotonica
Wine (since we're speaking Italian): Vino
A few sentences pulled from wordreference.com:
The marathon runner collapsed from exhaustion as soon as he crossed the finishing line.
Il maratoneta svenne per la stanchezza appena passata la linea d'arrivo.
Track-and-field athletes include runners, sprinters, and pole vaulters.
Tra gli atleti di atletica leggera ci sono i corridori, velocisti e saltatori con l'asta.
We're organizing a run for charity this weekend.
Questo fine settimana faremo una gara di beneficenza.
Those greasy tacos I ate at 2 in the morning gave me the runs.
Quei taco unti che ho mangiato alle due di notte mi hanno fatto venire la diarrea.
(Sorry, the translation sentence made me laugh, I had to include it for you.)
The marathon race is one of the highlights of the Olympic Games.
La maratona è il clou dei giochi olimpici.
He runs three miles every morning.
Percorre tre miglia tutte le mattine.
Fa tre miglia tutte le mattine.
I need to stretch my legs before I run the race.
Ho bisogno di allungare le gambe prima di correre in gara.
And for extra fun, conjugation of "to run" (correre) (in Italian, you customarily omit the pronoun, but I've included it anyway):
I run: Io corro
You run: Tu corri
He/she/it/you (formal) runs: lui/lei/egli/Lei corre
We run: Noi corriamo
You (pl) run: Voi correte
They run: Loro corrono
Past (for these other tenses, I'm only including I/we, most likely to be useful):
I ran: Io ho corso
We ran: Noi abbiamo corso
I will run: Io correrò
We will run: Noi correreremo (this word is just fun to say, and always makes me think of San Remo, a big Italian music festival)
I would run: Io correrei
We would run: Noi correremmo
I am running: Sto correndo
We are running: Stiamo correndo
Run (telling you, informal): Corri!
Run (you, formal): Corra!
Run (us, let's run!): Corriamo!
Now any runner is set to go to Italy and communicate the basics! Prego!