One Repetition Maximum (1RM) Calculator
Estimate maximum load for one repetition using validated formulas
Aviso Médico Importante
Esta calculadora es una herramienta educativa y de apoyo a la decisión clínica. Los resultados NO sustituyen la evaluación médica profesional, los exámenes de laboratorio ni el juicio clínico. Siempre consulte a un profesional de salud calificado para el diagnóstico, tratamiento y decisiones clínicas. Los cálculos se basan en fórmulas validadas científicamente, pero pueden no ser aplicables a todos los pacientes.
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What is 1RM?
One Repetition Maximum (1RM) is the maximum weight that can be lifted for one complete repetition of an exercise with proper form. It is used to determine training intensities and track strength progress.
How to Calculate
Enter the weight you lifted and the number of repetitions you performed (before failure). Choose a formula (Brzycki is most common). The calculator estimates your 1RM and provides training percentages for different intensity zones.
Limitations
These formulas provide estimates and accuracy decreases above 10 repetitions. Direct 1RM testing is more accurate but carries injury risk. Always use proper form and have a spotter. Consult a fitness professional before maximum strength testing.
FAQ
References
- 1. Brzycki M. Strength Testing—Predicting a One-Rep Max from Reps-to-Fatigue. Journal of Physical Education, Recreation & Dance. 1993;64(1):88-90.
- 2. Epley B. Poundage Chart. Boyd Epley Workout. Lincoln, NE: University of Nebraska Press; 1985.
- 3. Lander J. Maximums based on reps. NSCA Journal. 1985;6:60-61.
- 4. Baechle TR, Earle RW. Essentials of Strength Training and Conditioning. 3rd ed. Champaign, IL: Human Kinetics; 2008.