The best prompts include a few of: duration, discipline, equipment, body focus, intensity, constraint. You don't need all of them — just enough to paint a picture.
Good patterns
Duration + discipline + focus: "30-minute yoga flow focused on hips."
Duration + equipment + body part: "45 minutes of dumbbells, upper body push."
Discipline + context: "Climbing warm-up, 10 minutes."
Goal + time: "Lower back mobility, under 15 minutes."
Constraint-led: "No jumping, quiet bodyweight HIIT, 20 minutes."
Combine disciplines in one routine
"Yoga warm-up into kettlebell strength circuit, 40 minutes."
"Mobility flow followed by a short run intervals session."
"Stretch, core, and easy cardio — 25 minutes total."
Ask around a condition
"Something gentle for a tight lower back."
"Recovery routine after a heavy leg day."
"My shoulder's been sore — upper body without overhead pressing."
Speak like a trainer would
"Push-focused session, moderate intensity, end with a stretch."
"Sport prep for tennis — dynamic warm-up and shoulder activation."
What doesn't work as well
Too vague: "Workout." You'll get something, but less tailored. Add a length or focus.
Impossible combinations: "Full-body max strength in 5 minutes." The AI will do its best but will compromise on one of the constraints.
Iterate with editing
If the first result isn't quite right, edit it in place. See Editing a routine by talking to it.