Atlas Stone Calculator

The deadlift is the best predictor of atlas stone performance because both movements require similar posterior chain strength (glutes, hamstrings, lower back). The initial floor-to-lap portion of a stone lift is essentially a modified deadlift. Studies of strongman competitors show a strong correlation (r=0.85+) between deadlift 1RM and max stone lifted.

The calculator errs on the conservative side, especially for beginners. Atlas stones require specific technique that takes time to develop. A lighter stone allows you to practice proper form without risking bicep tears or lower back injuries. Once you have 10+ sessions with stones, you can progress to heavier weights more quickly.

Experience dramatically affects stone lifting efficiency. A beginner might use only 40% of their deadlift due to technique limitations, while an elite competitor can leverage 50%+ because their movement patterns are optimized. The calculator adjusts the deadlift ratio based on your reported experience level.

Tacky is allowed in most competitions and highly recommended for training heavy stones. Without tacky, grip becomes the limiting factor rather than strength. For technique work with lighter stones, you can train without tacky to build grip strength, but always use it when approaching competition weights.

Competition platforms typically range from 48" to 56" (122-142cm). Start training at the standard 52" (132cm) height. Once comfortable, practice with both higher and lower platforms to prepare for any competition setup. Higher platforms require more extension, while lower platforms demand faster transitions.

When you lap a stone, your abdominals and thighs create a shelf. Athletes with more body mass tend to have a larger natural shelf, which reduces the muscular demand during the lapping phase and lets them redirect more energy to the shoulder. A 220 lb athlete can generally lap a stone that is a higher percentage of their deadlift than a 165 lb athlete with the same deadlift number. This is a consistent pattern across competition data, not just theory.

Lap-loading means pulling the stone onto your lap from the floor, using your legs and a tacky wrap to hold it against your body. Shouldering means extending from the lap position to drive the stone onto one shoulder and stand up. These are two separate skills. Many beginners can lap a stone they cannot shoulder because the shoulder phase requires more explosive extension and core stability. The calculator targets a weight you can complete the full movement with, not just the lap phase.

The ratios are calibrated for spherical atlas stones, which have a specific center-of-mass and tacky surface interaction. Kegs are lighter per diameter and shift their center of mass when tilted, making the movement easier per pound. Sandbags are generally harder because they have no rigid shell to brace against. If you want a rough estimate for those events, start with 10 to 15 percent adjustments from this calculator’s output, then verify with actual practice reps before committing to a competition weight.

Most intermediates can add 10 to 20 lbs to their working stone every four to six weeks when training the event once per week. Progress depends on both strength gains and technique consolidation. If you can complete five clean reps to shoulder on your current stone, you are ready to move up. If you are still grinding single reps, stay at that weight for another cycle. Stone progress is slower than barbell progress but more consistent once technique is locked in.