Tempo (Rep Cadence)
Also known as: Tempo Notation, TUT Prescription, Eccentric:Pause:Concentric:Pause
A four-number notation (e.g. 3-1-1-0) specifying how many seconds each phase of a rep should take: eccentric (lowering), bottom pause, concentric (lifting), top pause. Tempo is the primary tool for prescribing time-under-tension explicitly.
Formula
Tempo notation: [eccentric]-[bottom pause]-[concentric]-[top pause]
3-1-1-0 = 3s lowering, 1s pause at bottom, 1s lifting, 0s at top
5-0-X-0 = 5s lowering, no pause, eXplosive lifting, no pause ("X" = max speed)
Total rep time = sum of the four numbers (use rep speed × reps for total TUT)Example
Squat at 3-2-1-0 for 8 reps = (3+2+1+0) × 8 = 48 seconds of time-under-tension per set. Compare to a regular squat at ~2-0-1-0 for 8 reps = 24 s TUT — same exercise, same reps, double the stimulus duration.
How Afitpilot Uses This
Afitpilot's plan generator can prescribe tempo in the session prescription. Tempo prescriptions are displayed in the session UI; we don't yet auto-verify the athlete actually hit the tempo (would require video or accelerometer). Tempo prescriptions feed into the prescribed duration of a session, which affects the AU calculation indirectly through sRPE × duration.
Tempo applications by training goal
| Who / Context | Value | Note |
|---|---|---|
| Hypertrophy | 3-1-1-0 to 4-0-2-0 | Higher TUT per rep; favours metabolic stress and mechanical tension |
| Maximal strength | 2-0-X-0 | Controlled eccentric, explosive concentric; max force production |
| Power / speed | 1-0-X-0 | Minimise eccentric time; train rate of force development |
| Tendon adaptation | 3-0-3-0 or 5-0-5-0 | Heavy slow resistance for tendinopathy rehab (Beyer 2015) |
| Active aging (60+) | 3-1-2-0 default | Controlled tempo reduces injury risk vs. rushed reps |
Known Limitations
- •Tempo compliance is hard to enforce without video. Athletes asked to do 5-second eccentrics typically drift to 2-3 seconds over a set as fatigue accumulates, and we can't detect this.
- •The classical 4-number notation is more granular than most athletes need or can execute. Many programs simplify to "3s down, explosive up" or just a TUT target.
- •Tempo prescriptions don't fit time-based exercises (planks, holds) or speed-based exercises (sprints, jumps) — the notation is specific to repetition-based resistance training.
- •Adding tempo to a heavy compound lift (e.g. 5-0-1-0 squats at RPE 8) substantially changes the recovery cost. We don't currently adjust the rest period or load suggestion when tempo is prescribed.
Science Context
Tempo as an explicit programming variable was popularised by Charles Poliquin in the 1990s, who introduced the four-number notation that became standard in strength coaching. The research base is moderate: time-under-tension matters for hypertrophy at the extremes (very fast vs. very slow reps differ in stimulus), but within the 1-6 second per rep range, total volume and proximity to failure matter more than tempo (Schoenfeld 2015). The strongest evidence for tempo manipulation is in tendon rehab: heavy slow resistance protocols (Kongsgaard 2009, Beyer 2015) show clear benefits over rushed eccentrics for tendinopathy.