Calculate your one rep max (1RM) using the proven Epley formula. Determine maximum strength for powerlifting, weightlifting, and strength training program design.
1. What is One Rep Max (1RM)?Your one repetition maximum (1RM) represents the maximum load you can lift for a single repetition with proper biomechanical form. This metric serves as the gold standard for assessing absolute strength capacity and is fundamental for periodized training program design, load progression, and strength sport competition preparation in powerlifting, Olympic weightlifting, and strongman athletics.Formula: Epley Formula - 1RM = Weight × (1 + Reps/30)
2. Periodization Training Intensity Zones Based on 1RM| % of 1RM | Rep Range | Training Adaptation | Rest Period |
|---|
| 90-100% | 1-3 reps | Maximal Strength | 3-5 min |
| 80-90% | 3-6 reps | Strength Power | 2-4 min |
| 65-80% | 6-12 reps | Hypertrophy | 1-3 min |
| 50-65% | 12+ reps | Muscular Endurance | 30-90 sec |
3. Evidence-Based Safety Protocols for Maximal Strength Testing✅ Essential Safety Protocols- • Progressive warm-up protocol (general → specific)
- • Qualified spotter with proper technique
- • Optimal recovery state (48-72h post-training)
- • Biomechanically sound movement patterns
- • Multi-joint compound exercises only
- • Proper breathing techniques (Valsalva maneuver)
❌ Risk Factors to Avoid- • Testing under accumulated fatigue
- • Compensatory movement patterns
- • Single-joint isolation exercises
- • Frequent maximal attempts (monthly)
- • Novice lifters without technique mastery
- • Inadequate neuromuscular preparation
4. Alternative 1RM Prediction FormulasEpley Formula (Most Popular)1RM = Weight × (1 + Reps/30)Best for: 1-10 reps, most accurate for powerlifting movements
Brzycki Formula1RM = Weight × (36/(37-Reps))Best for: 2-10 reps, conservative estimates
Lombardi Formula1RM = Weight × Reps^0.10Best for: Higher rep ranges (10-15 reps)
O'Conner Formula1RM = Weight × (1 + Reps/40)Best for: Beginner to intermediate lifters
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