Training to Failure: When It Helps and When It Hurts
TL;DR: Failure is useful for isolation exercises but costly for compounds. Stop 1-3 reps shy of failure on big lifts; push closer on machines and isolations.
Rules
- Use failure on isolations; stay 1–2 RIR on compounds for safety.
- Failure increases fatigue—use sparingly (last set only).
- Track RIR to manage stimulus-to-fatigue ratio.