Every calculator on TalkGym uses a published formula or chart, named and linked on its page:
- One-rep max: NSCA, "Training Load Chart" (percent of 1RM by repetitions); Epley (1985) and Brzycki one-rep max equations, as summarized in "One-repetition maximum" (Wikipedia).
- RPE: Zourdos et al., "Novel resistance training-specific RPE scale measuring repetitions in reserve," J Strength Cond Res 30(1):267-275 (2016).
- Race prediction: Peter S. Riegel, "Athletic Records and Human Endurance," American Scientist 69(3):285-290 (1981).
- Heart rate: American Heart Association, "Target Heart Rates Chart" (reviewed Aug 12, 2024); Tanaka, Monahan and Seals, "Age-predicted maximal heart rate revisited," J Am Coll Cardiol 37(1):153-156 (2001); Cleveland Clinic, "Exercise Heart Rate Zones Explained" (Oct 6, 2025).
- Bars and plates: International Weightlifting Federation, equipment.
- Powerlifting scores: International Powerlifting Federation, "The IPF GL Coefficients for Relative Scoring" (March 2020); DOTS coefficients as published in Kopayev, Onyshchenko and Stetsenko, "Evaluation of Wilks, Wilks-2, DOTS, IPF and GoodLift formulas" (via Inch Calculator).
Pace and distance numbers are plain arithmetic (1 mile = 1.609344 km). Calculators run in your browser. Checked October 17, 2026. These tools are for training guidance, not medical advice.