CoachFrom the Coach guide
One of the week's hard days.
A hard session: tempo, intervals, hills or fartlek.
What it is for
Quality sessions make you faster. Each kind trains a different part of your fitness.
Which kind
The session title says which kind it is. Run club is often a tempo or an interval session.
The usual session
Before race-specific training, your hard run is cruise intervals: 5 × 6 min a little slower than tempo pace, with 1 min of walking or easy jogging between. It is hard enough to train you and easy to repeat. Later weeks also use tempo runs. Coach chooses this repeatable session to balance training and recovery.
Why plans use it
Plans have up to 2 each week, never on back-to-back days, with easy days around them.
When runs miss their target
If 2 hard runs in a row are slower than planned or cut short, Coach changes the next one. When your fatigue is low, it is the same session again. When your fatigue is building, it is an easier session, and the week does not get longer. If 2 hard runs in a row feel easy at their pace, Coach plans a threshold test to check your paces. Hot days and run club sessions do not count. Coach chooses these responses to balance training with your recovery.
Not the same as
Long run: easy effort, for longer. A quality session is short and hard.