Hills
Hill reps and vert work, because flat is a lie.
The hill
Flat is a lie most runners tell themselves. Hills are where you get strong, find your form, and learn to suffer a little on purpose.
The session
warm 15 min easy reps 6–10 × 60–90s up recover jog back down cool 10 min easy
Why it works
Vert builds the engine and the legs at once. One hill session a week is worth two flat tempos.