1RM Calculator & Strength Zones

"Strength Without the Risk." The Journey Endurance Strength Lab uses the industry-standard Brzycki Formula to estimate your 1-Rep Max (1RM) without the heavy toll of testing to failure. By analyzing your sub-maximal lifts, we calculate a theoretical ceiling to help frame your training zones.

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A Note on Auto-Regulation: While this tool provides precise data, your body is the ultimate feedback loop. Use these numbers as a baseline, but always prioritize Rate of Perceived Exertion (RPE) and technical breakdown over the spreadsheet. A calculated max is a target, not a rule.