HIT vs 5/3/1. Which actually builds muscle?

The honest score

• Strength gains: Carpinelli & Otto's meta-analysis of 70+ studies found one set to failure produces equivalent strength gains to multiple-set protocols in both novices and trained lifters.
• Hypertrophy: Westcott & Winnett (n=1,644) — no significant difference between single-set and multi-set when both groups train to failure.
• Time cost: 5/3/1 ≈ 4h/week. HIT ≈ 15 min/week.
• Joint wear: 5/3/1 uses barbells with momentum. HIT's 10/10 cadence removes it.

When 5/3/1 wins

If you compete in powerlifting and need to peak a 1RM on command, 5/3/1's percentage-based grind is purpose-built. If you love spending time under the bar, you'll enjoy it more.

When HIT wins

If you want maximum strength & muscle per minute spent, and you're training for the next 40 years rather than the next powerlifting meet — HIT wins decisively. The recovery window matters more than the work itself.

What Intensiq does that programs can't

• Detects true failure via time-under-load + form drift, not a percentage chart.
• HRV-based readiness — your next session moves when your nervous system needs it to.
• Auto-progression only bumps load when the previous set hit honest failure.