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The research behind Ægir Iron

Every published source a number, a rule or a piece of guidance in Ægir Iron rests on, and what each one is used for.

This list is generated from the bibliography inside the app, the same one behind its Sources screen, so it cannot fall behind the code. Most sources link to the paper, dataset or page. Where a number is our own decision rather than a published finding, it is listed under our own numbers with the work it is anchored to, so nobody mistakes it for something a study reported.

203 published sources and 59 numbers of our own, from the bibliography inside the app.

Weekly volume and targets

  1. Meta-analysis Androulakis-Korakakis P, Fisher JP, Steele J (2020). The Minimum Effective Training Dose Required to Increase 1RM Strength in Resistance-Trained Men: A Systematic Review and Meta-Analysis. Sports Med. 2020;50(4):751-765.
    • Trained lifters still gain strength on a few weekly sets of a lift, so the targets are for size, not a strength minimum
  2. Study Androulakis-Korakakis P, Michalopoulos N, Fisher JP, Keogh J, Loenneke JP, Helms E, Wolf M, Nuckols G, Steele J (2021). The Minimum Effective Training Dose Required for 1RM Strength in Powerlifters. Front Sports Act Living. 2021;3:713655.
    • Powerlifters report making strength gains on a few weekly sets of each competition lift
  3. Review Currier BS, D'Souza AC, Singh MAF, et al. (2026). American College of Sports Medicine Position Stand. Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults: An Overview of Reviews. Med Sci Sports Exerc. 2026;58(4):851-872.
    • A second, independent basis for the ~10 sets per muscle per week landmark (137 systematic reviews)
  4. Meta-analysis Pelland JC, Remmert JF, Robinson ZP, Hinson SR, Zourdos MC (2026). The Resistance Training Dose Response: Meta-Regressions Exploring the Effects of Weekly Volume and Frequency on Muscle Hypertrophy and Strength Gains. Sports Med. 2026;56(2):481-505 (epub 2025-12-04).
    • Counting an indirect set as a fraction of a set (the fractional volume model)
    • More weekly volume keeps adding muscle, with diminishing returns (sooner for strength than for size)
  5. Book Potach DH, Chu DA (2016). Program design and technique for plyometric training. In: Haff GG, Triplett NT (eds), Essentials of Strength Training and Conditioning, 4th ed.. Human Kinetics. 2016:471-520.
    • Foot contacts per plyometric session: about 80 to 100 for a beginner, 100 to 120 intermediate, 120 to 140 advanced
  6. Study Schoenfeld BJ, Contreras B, Krieger J, et al. (2019). Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men. Med Sci Sports Exerc. 2019;51(1):94-103.
    • Why ~10 sets is a productive floor rather than a ceiling
  7. Meta-analysis Schoenfeld BJ, Ogborn D, Krieger JW (2017). Dose-response relationship between weekly resistance training volume and increases in muscle mass: a systematic review and meta-analysis. J Sports Sci. 2017;35(11):1073-1082.
    • The ~10 hard sets per muscle per week landmark the weekly targets are anchored to

Which muscles an exercise trains

  1. Study Albarello JCDS, Cabral HV, Leitão BFM, Halmenschlager GH, Lulic-Kuryllo T, Matta TTD (2022). Non-uniform excitation of pectoralis major induced by changes in bench press inclination leads to uneven variations in the cross-sectional area measured by panoramic ultrasonography. J Electromyogr Kinesiol. 2022;67:102722.
    • Reviewed, not used: the incline grows the upper pec, which the body figure cannot show on its own
  2. Study Andersen LL, Kjaer M, Andersen CH, Hansen PB, Zebis MK, Hansen K, et al. (2008). Muscle activation during selected strength exercises in women with chronic neck muscle pain. Phys Ther. 2008;88(6):703-711.
    • A lateral raise credits the traps as a helper
  3. Study Andersen V, Fimland MS, Brennset O, et al. (2014). Muscle activation and strength in squat and Bulgarian squat on stable and unstable surface. Int J Sports Med. 2014;35(14):1196-1202.
    • Single-leg squats credit a small share of obliques for the anti-rotation demand
  4. Study Andersen V, Fimland MS, Wiik E, Skoglund A, Saeterbakken AH (2014). Effects of grip width on muscle strength and activation in the lat pull-down. J Strength Cond Res. 2014;28(4):1135-1142.
    • Reviewed, not used: lat pull-down grip width
  5. Study Arauz PG, Garcia G, Llerena J, Kao I (2026). Biomechanical and neuromuscular differences between the snatch and clean in elite weightlifters. J Biomech. 2026;195:113106.
    • A snatch credits the shoulders as a prime mover and a clean as a helper
  6. Meta-analysis Arntz F, Mkaouer B, Markov A, Schoenfeld BJ, Moran J, Ramirez-Campillo R, et al. (2022). Effect of Plyometric Jump Training on Skeletal Muscle Hypertrophy in Healthy Individuals: A Systematic Review With Multilevel Meta-Analysis. Front Physiol. 2022;13:888464.
    • Jumps keep the quads as the lead share
  7. Study Barbalho M, Coswig V, Souza D, Serrão JC, Hebling Campos M, Gentil P (2020). Back Squat vs. Hip Thrust Resistance-training Programs in Well-trained Women. Int J Sports Med. 2020;41(5):306-310.
    • A hip thrust credits the quads a helper share only
  8. Study Bautista D, Durke D, Cotter JA, Escobar KA, Schick EE (2020). A Comparison of Muscle Activation Among the Front Squat, Overhead Squat, Back Extension and Plank. Int J Exerc Sci. 2020;13(1):714-722.
    • An overhead squat credits traps 0.5 and shoulders 0.3
  9. Study Bernasconi SM, Tordi NR, Parratte BM, Rouillon JD (2009). Can shoulder muscle coordination during the support scale at ring height be replicated during training exercises in gymnastics?. J Strength Cond Res. 2009;23(8):2381-2388.
    • Reviewed, not used: the swallow on rings and its training drills
  10. Study Bozkurt Ö, Erdağ D, Tinazci C, Burgul N, Bekiroğulları H (2026). Mechanobiological and neuromuscular responses to foot-position variations during front and back squat exercises. Front Physiol. 2026;16:1727141.
    • Reviewed, not used: heel and forefoot elevation in the squat
  11. Study Cadeo GM, Fujita RA, Villalba MM, Silva NRS, Júnior CI, Pearcey GEP, et al. (2023). Myoelectric activity and improvements in strength and hypertrophy are unaffected by the ankle position during prone leg curl exercise - a within person randomized trial. Eur J Sport Sci. 2023;23(11):2200-2209.
    • Reviewed, not used: ankle position in the leg curl
  12. Study Calatayud J, Borreani S, Colado JC, Martin F, Tella V, Andersen LL (2015). Bench press and push-up at comparable levels of muscle activity results in similar strength gains. J Strength Cond Res. 2015;29(1):246-253.
    • Push ups credit the same muscles as a bench press
  13. Study Camara KD, Coburn JW, Dunnick DD, Brown LE, Galpin AJ, Costa PB (2016). An Examination of Muscle Activation and Power Characteristics While Performing the Deadlift Exercise With Straight and Hexagonal Barbells. J Strength Cond Res. 2016;30(5):1183-1188.
    • The trap bar deadlift credits more quads and less hamstrings and lower back than a straight bar
  14. Study Campos YAC, Vianna JM, Guimarães MP, Oliveira JLD, et al. (2020). Different Shoulder Exercises Affect the Activation of Deltoid Portions in Resistance-Trained Individuals. J Hum Kinet. 2020;75:5-14.
    • A chest fly credits the front delt as much as a bench press does
  15. Study Chaves SFN, Rocha-Júnior VA, Encarnação IGA, Martins-Costa HC, et al. (2020). Effects of Horizontal and Incline Bench Press on Neuromuscular Adaptations in Untrained Young Men. Int J Exerc Sci. 2020;13(6):859-872.
    • Reviewed, not used: the incline grows the upper pec, which the body figure cannot show on its own
  16. Study Christian JR, Gothart SE, Graham HK, Barganier KD, Whitehead PN (2023). Analysis of the Activation of Upper-Extremity Muscles During Various Chest Press Modalities. J Strength Cond Res. 2023;37(2):265-269.
    • Reviewed, not used: incline against decline, with no flat comparison
  17. Study Cogley RM, Archambault TA, Fibeger JF, Koverman MM, Youdas JW, Hollman JH (2005). Comparison of muscle activation using various hand positions during the push-up exercise. J Strength Cond Res. 2005;19(3):628-633.
    • A diamond push up credits the triceps as a prime mover beside the chest
  18. Study Collings TJ, Horsman A, Hams AH, McGill A, Watts D, Hambly MJ, et al. (2026). Hip Adductor Muscle Forces during Strength Training and Rehabilitation Exercises. Med Sci Sports Exerc. 2026;58(8):1751-1763.
    • A deadlift from the floor credits the adductors 0.5, conventional as well as sumo
    • A Copenhagen plank credits adductors 1
  19. Study Conley MS, Stone MH, Nimmons M, Dudley GA (1997). Specificity of resistance training responses in neck muscle size and strength. Eur J Appl Physiol Occup Physiol. 1997;75(5):443-448.
    • Only direct neck work credits the neck
  20. Study Contreras B, Vigotsky AD, Schoenfeld BJ, Beardsley C, Cronin J (2015). A Comparison of Gluteus Maximus, Biceps Femoris, and Vastus Lateralis Electromyographic Activity in the Back Squat and Barbell Hip Thrust Exercises. J Appl Biomech. 2015;31(6):452-458.
    • A hip thrust or glute bridge credits hamstrings 0.3 and quads 0.3
  21. Study Coratella G, Tornatore G, Longo S, Esposito F, Cè E (2020). Specific prime movers' excitation during free-weight bench press variations and chest press machine in competitive bodybuilders. Eur J Sport Sci. 2020;20(5):571-579.
    • Reviewed, not used for the decline bench or the machine; with a second study, sets the incline triceps share
  22. Study Coratella G, Tornatore G, Longo S, Esposito F, Cè E (2022). An Electromyographic Analysis of Romanian, Step-Romanian, and Stiff-Leg Deadlift: Implication for Resistance Training. Int J Environ Res Public Health. 2022;19(3):1903.
    • Reviewed, not used: Romanian against stiff-leg deadlift
  23. Study Coratella G, Tornatore G, Longo S, Esposito F, Cè E (2020). An Electromyographic Analysis of Lateral Raise Variations and Frontal Raise in Competitive Bodybuilders. Int J Environ Res Public Health. 2020;17(17):6015.
    • A lateral raise credits the traps as a helper; a front raise does not
  24. Study Coratella G, Tornatore G, Longo S, Toninelli N, Padovan R, Esposito F, et al. (2023). Biceps Brachii and Brachioradialis Excitation in Biceps Curl Exercise: Different Handgrips, Different Synergy. Sports (Basel). 2023;11(3):64.
    • A reverse curl credits the forearms as a prime mover; a hammer curl scores as a curl
  25. Study de Almeida Paz I, Frigotto MF, Cardoso CA, Rabello R, Rodrigues R (2022). Hip abduction machine is better than free weights to target the gluteus medius while minimizing tensor fascia latae activation. J Bodyw Mov Ther. 2022;30:160-167.
    • Reviewed, not used: gluteus medius in hip abduction
  26. Study Delgado J, Drinkwater EJ, Banyard HG, Haff GG, Nosaka K (2019). Comparison Between Back Squat, Romanian Deadlift, and Barbell Hip Thrust for Leg and Hip Muscle Activities During Hip Extension. J Strength Cond Res. 2019;33(10):2595-2601.
    • Reviewed, not used: squat, Romanian deadlift and hip thrust at 1RM
  27. Review Di Fonza D, Di Claudio G, Colantuono G, Persichini L, Cerulo N, Sangregorio B, et al. (2026). Electromyographic Analysis of Latissimus Dorsi Activation During Common Resistance Training Exercises: A Narrative Review. J Funct Morphol Kinesiol. 2026;11(3):315.
    • A pullover credits the chest as a prime mover beside the lats; pulldown grip width moves nothing
  28. Study Dickie JA, Faulkner JA, Barnes MJ, Lark SD (2017). Electromyographic analysis of muscle activation during pull-up variations. J Electromyogr Kinesiol. 2017;32:30-36.
    • Reviewed, not used: pull-up grips
  29. Study Dunnick DD, Brown LE, Coburn JW, Lynn SK, Barillas SR (2015). Bench Press Upper-Body Muscle Activation Between Stable and Unstable Loads. J Strength Cond Res. 2015;29(12):3279-3283.
    • Reviewed, not used: an unstable hanging load keeps the bench press shares
  30. Study Ebben WP, Simenz C, Jensen RL (2008). Evaluation of plyometric intensity using electromyography. J Strength Cond Res. 2008;22(3):861-868.
    • Reviewed, not used: plyometric exercises ranked by muscle activity
  31. Study Erdağı K, Poyraz N (2020). The determination of the cross-sectional area of the lumbar erector spinae muscles of Olympic style weightlifting athletes by using MRI. J Back Musculoskelet Rehabil. 2020;33(3):405-412.
    • Reviewed, not used: weightlifters' lower back size
  32. Study Escamilla RF, Babb E, DeWitt R, Jew P, Kelleher P, Burnham T, et al. (2006). Electromyographic analysis of traditional and nontraditional abdominal exercises: implications for rehabilitation and training. Phys Ther. 2006;86(5):656-671.
    • Rollouts and hanging raises credit lats 0.3
  33. Study Escamilla RF, Francisco AC, Kayes AV, Speer KP, Moorman CT (2002). An electromyographic analysis of sumo and conventional style deadlifts. Med Sci Sports Exerc. 2002;34(4):682-688.
    • Sumo credits the quads as a prime mover, and the adductors are measured in both deadlift styles
  34. Study Farias DA, Willardson JM, Paz GA, Bezerra ES, Miranda H (2017). Maximal Strength Performance and Muscle Activation for the Bench Press and Triceps Extension Exercises Adopting Dumbbell, Barbell, and Machine Modalities Over Multiple Sets. J Strength Cond Res. 2017;31(7):1879-1887.
    • A dumbbell press credits the triceps a smaller share than a barbell or machine press
  35. Study Fenwick CM, Brown SH, McGill SM (2009). Comparison of different rowing exercises: trunk muscle activation and lumbar spine motion, load, and stiffness. J Strength Cond Res. 2009;23(5):1408-1417.
    • A standing bent-over row credits the lower back as a helper
  36. Study Fischer J, Burger C, Manieu Seguel JA, Rodoplu C, Paternoster FK, Tilp M, Konrad A (2025). Acute muscle excitation response across various bench press ranges of motion. Sci Rep. 2025;15(1):14105.
    • Reviewed, not used: board, pin and floor presses keep the bench press shares
  37. Study Frouin A, Le Sant G, Barbier L, Jacquemin E, McNair PJ, Ellis R, et al. (2024). Individual distribution of muscle hypertrophy among hamstring muscle heads: Adding muscle volume where you need is not so simple. Scand J Med Sci Sports. 2024;34(3):e14608.
    • Reviewed, not used: hamstring growth from leg curls and stiff-leg deadlifts
  38. Study Geisler S, Havers T, Isenmann E, Schulze J, Lourens LK, Nowak J, et al. (2023). Effects of Expertise on Muscle Activity during the Hang Power Clean and Hang Power Snatch Compared to Snatch and Clean Pulls - An Explorative Analysis. J Sports Sci Med. 2023;22(4):778-789.
    • The lifts and the pulls share the legs, hips and traps
  39. Review Glassbrook DJ, Helms ER, Brown SR, Storey AG (2017). A Review of the Biomechanical Differences Between the High-Bar and Low-Bar Back-Squat. J Strength Cond Res. 2017;31(9):2618-2634.
    • A low-bar squat credits more glutes and lower back than a high-bar one
  40. Study Gottschall JS, Hastings B, Becker Z (2018). Muscle Activity Patterns do not Differ Between Push-Up and Bench Press Exercises. J Appl Biomech. 2018;34(6):442-447.
    • Push ups from the knees or the toes, and a push up against a bench press, share one set of muscles
  41. Study Gundersen AH, van den Tillaar R, Falch HN, Fredriksen AB, Larsen S (2025). A Biomechanical Comparison Between Conventional, Sumo, and Hex-Bar Deadlifts Among Resistance Trained Women. J Strength Cond Res. 2025;39(3):281-288.
    • The trap bar deadlift is the knee-dominant pull and credits the adductors with the straight bar
  42. Study Hanen NC, Ben Mansour K, Ertel GN, Duchene Y, Gauchard GC (2025). Biomechanical analysis of conventional and sumo deadlift. Front Bioeng Biotechnol. 2025;13:1597209.
    • Sumo credits the quads as a prime mover
  43. Study Hecker KA, Carlson LA, Lawrence MA (2019). Effects of the Safety Squat Bar on Trunk and Lower-Body Mechanics During a Back Squat. J Strength Cond Res. 2019;33(Suppl 1):S45-S51.
    • Reviewed, not used: the safety squat bar lowered leg activity at a lighter load
  44. Study Helland C, Hole E, Iversen E, Olsson MC, Seynnes O, Solberg PA, et al. (2017). Training Strategies to Improve Muscle Power: Is Olympic-style Weightlifting Relevant?. Med Sci Sports Exerc. 2017;49(4):736-745.
    • Cleans and snatches credit the quads as a helper, not a prime mover
  45. Study Hernández-Belmonte A, Martínez-Cava A, Buendía-Romero Á, Franco-López F, Pallarés JG (2023). Free-Weight and Machine-Based Training Are Equally Effective on Strength and Hypertrophy: Challenging a Traditional Myth. Med Sci Sports Exerc. 2023;55(12):2316-2327.
    • Reviewed, not used: Smith machine and machine presses keep the free-weight shares
  46. Study Hindle B, Lorimer A, Winwood P, Brimm D, Keogh JWL (2021). The biomechanical characteristics of the strongman atlas stone lift. PeerJ. 2021;9:e12066.
    • Reviewed, not used: atlas stone kinematics
  47. Study Hindle BR, Lorimer A, Winwood P, Brimm D, Keogh JWL (2021). The Biomechanical Characteristics of the Strongman Yoke Walk. Front Sports Act Living. 2021;3:670297.
    • Reviewed, not used: yoke walk kinematics
  48. Review Hindle BR, Lorimer A, Winwood P, Keogh JWL (2019). The Biomechanics and Applications of Strongman Exercises: a Systematic Review. Sports Med Open. 2019;5(1):49.
    • Tabulates the carry EMG the strongman shares use
  49. Study Ikeda Y, Miyatsuji K, Kawabata K, Fuchimoto T, Ito A (2009). Analysis of trunk muscle activity in the side medicine-ball throw. J Strength Cond Res. 2009;23(8):2231-2240.
    • A rotational throw or side slam credits obliques 0.7
  50. Study Işiklar Ç, Paköz B, Turgut E (2026). Shoulder muscular activation during common kettlebell exercises: a randomized cross-sectional surface EMG study. Physiother Theory Pract. 2026, online ahead of print.
    • Reviewed, not used: shoulder muscles in kettlebell swings and presses
  51. Study Jaeggi JS, Achermann B, Lorenzetti SR (2024). Female Lower Body Muscle Forces: A Musculoskeletal Modeling Comparison of Back Squats, Split Squats and Good Mornings. J Funct Morphol Kinesiol. 2024;9(2):68.
    • Reviewed, not used: split squat and back squat muscle forces
  52. Study Kennedy D, Casebolt JB, Farren GL, Fiaud V, Bartlett M, Strong L (2024). Electromyographic differences of the gluteus maximus, gluteus medius, biceps femoris, and vastus lateralis between the barbell hip thrust and barbell glute bridge. Sports Biomech. 2024;23(12):2935-2949.
    • Reviewed, not used: hip thrust against glute bridge
  53. Study Kikuchi N, Nakazato K (2017). Low-load bench press and push-up induce similar muscle hypertrophy and strength gain. J Exerc Sci Fit. 2017;15(1):37-42.
    • Push ups credit the same muscles as a bench press
  54. Study Kinoshita M, Maeo S, Kobayashi Y, Eihara Y, Nishizawa N, Kusagawa Y, et al. (2026). Hypertrophic Effects of Single- versus Multi-Joint Exercise: A Direct Comparison between Knee Extension and Leg Press. Med Sci Sports Exerc. 2026;58(7):1566-1580.
    • A leg press credits the glutes as a prime mover and the adductors as a helper
  55. Study Kinoshita M, Maeo S, Kobayashi Y, Eihara Y, Ono M, Sato M, et al. (2023). Triceps surae muscle hypertrophy is greater after standing versus seated calf-raise training. Front Physiol. 2023;14:1272106.
    • Reviewed, not used: standing against seated calf raises
  56. Study Kleiber T, Kunz L, Disselhorst-Klug C (2015). Muscular coordination of biceps brachii and brachioradialis in elbow flexion with respect to hand position. Front Physiol. 2015;6:215.
    • A reverse curl credits the forearms as a prime mover
  57. Study Kohiruimaki R, Maeo S, Kanehisa H (2019). Suspended Push-up Training Augments Size of not only Upper Limb but also Abdominal Muscles. Int J Sports Med. 2019;40(12):789-795.
    • A push up on rings credits the abs and obliques as well as the pressing muscles
  58. Study Kohler JM, Flanagan SP, Whiting WC (2010). Muscle activation patterns while lifting stable and unstable loads on stable and unstable surfaces. J Strength Cond Res. 2010;24(2):313-321.
    • A dumbbell or kettlebell overhead press credits the triceps a smaller share than a barbell press
  59. Study Kotarsky CJ, Christensen BK, Miller JS, Hackney KJ (2018). Effect of Progressive Calisthenic Push-up Training on Muscle Strength and Thickness. J Strength Cond Res. 2018;32(3):651-659.
    • Reviewed, not used: push ups against the bench press
  60. Study Krzysztofik M, Golas A, Wilk M, Stastny P, Lockie RG, Zajac A (2020). A Comparison of Muscle Activity Between the Cambered and Standard Bar During the Bench Press Exercise. Front Physiol. 2020;11:875.
    • Reviewed, not used: a cambered bar keeps the bench press shares
  61. Study Kubo K, Ikebukuro T, Yata H (2019). Effects of squat training with different depths on lower limb muscle volumes. Eur J Appl Physiol. 2019;119(9):1933-1942.
    • A full back squat credits the glutes as a prime mover, the adductors more than a bystander, and the hamstrings only as a helper
  62. Study Larsen S, Gomo O, van den Tillaar R (2020). A Biomechanical Analysis of Wide, Medium, and Narrow Grip Width Effects on Kinematics, Horizontal Kinetics, and Muscle Activity on the Sticking Region in Recreationally Trained Males During 1-RM Bench Pressing. Front Sports Act Living. 2020;2:637066.
    • A close grip bench credits the triceps one step above a standard bench
  63. Study Larsen S, Wolf M, Schoenfeld BJ, Sandberg NØ, Fredriksen AB, Kristiansen BS, et al. (2025). Dumbbell versus cable lateral raises for lateral deltoid hypertrophy: an experimental study. Front Physiol. 2025;16:1611468.
    • Reviewed, not used: dumbbell against cable lateral raises
  64. Study Lauver JD, Cayot TE, Scheuermann BW (2016). Influence of bench angle on upper extremity muscular activation during bench press exercise. Eur J Sport Sci. 2016;16(3):309-316.
    • Reviewed, not used: the decline bench keeps the bench press shares
  65. Study Lehman GJ (2005). The influence of grip width and forearm pronation/supination on upper-body myoelectric activity during the flat bench press. J Strength Cond Res. 2005;19(3):587-591.
    • A close grip bench credits the triceps one step above a standard bench
  66. Study Lockie RG, Callaghan SJ, Moreno MR, et al. (2017). An Investigation of the Mechanics and Sticking Region of a One-Repetition Maximum Close-Grip Bench Press versus the Traditional Bench Press. Sports (Basel). 2017;5(3):46.
    • Reviewed, not used: close grip bench bar mechanics
  67. Study Lusk SJ, Hale BD, Russell DM (2010). Grip width and forearm orientation effects on muscle activity during the lat pull-down. J Strength Cond Res. 2010;24(7):1895-1900.
    • Reviewed, not used: lat pull-down grip width and forearm orientation
  68. Study Lyons BC, Mayo JJ, Tucker WS, Wax B, Hendrix RC (2017). Electromyographical Comparison of Muscle Activation Patterns Across Three Commonly Performed Kettlebell Exercises. J Strength Cond Res. 2017;31(9):2363-2370.
    • A kettlebell or dumbbell snatch or clean credits the swing's hips
  69. Study Maddigan ME, Button DC, Behm DG (2014). Lower-limb and trunk muscle activation with back squats and weighted sled apparatus. J Strength Cond Res. 2014;28(12):3346-3353.
    • A sled push keeps calves 0.5 and no lower back
  70. Study Maeo S, Huang M, Wu Y, Sakurai H, Kusagawa Y, Sugiyama T, et al. (2021). Greater Hamstrings Muscle Hypertrophy but Similar Damage Protection after Training at Long versus Short Muscle Lengths. Med Sci Sports Exerc. 2021;53(4):825-837.
    • Reviewed, not used: seated against prone leg curls
  71. Study Maeo S, Wu Y, Huang M, Sakurai H, Kusagawa Y, Sugiyama T, et al. (2023). Triceps brachii hypertrophy is substantially greater after elbow extension training performed in the overhead versus neutral arm position. Eur J Sport Sci. 2023;23(7):1240-1250.
    • Reviewed, not used: overhead against neutral triceps extensions
  72. Review Malíř R, Chrudimský J, Šteffl M, Stastny P (2023). A Systematic Review of Dynamic, Kinematic, and Muscle Activity during Gymnastic Still Rings Elements. Sports (Basel). 2023;11(3):50.
    • Reviewed, not used: still rings elements
  73. Study McAllister MJ, Schilling BK, Hammond KG, Weiss LW, Farney TM (2013). Effect of grip width on electromyographic activity during the upright row. J Strength Cond Res. 2013;27(1):181-187.
    • An upright row credits the biceps as a helper
  74. Study McCaw ST, Melrose DR (1999). Stance width and bar load effects on leg muscle activity during the parallel squat. Med Sci Sports Exerc. 1999;31(3):428-436.
    • A squat credits the hamstrings 0.3, a helper
    • Reviewed, not used: a sumo squat credits the adductors more than a back squat
  75. Study McGill SM, Cannon J, Andersen JT (2014). Muscle activity and spine load during pulling exercises: influence of stable and labile contact surfaces and technique coaching. J Electromyogr Kinesiol. 2014;24(5):652-665.
    • Reviewed, not used: spine load across pulling exercises
  76. Study McGill SM, Marshall LW (2012). Kettlebell swing, snatch, and bottoms-up carry: back and hip muscle activation, motion, and low back loads. J Strength Cond Res. 2012;26(1):16-27.
    • A kettlebell swing keeps glutes 0.9 and lower back 0.5
  77. Study McGill SM, McDermott A, Fenwick CM (2009). Comparison of different strongman events: trunk muscle activation and lumbar spine motion, load, and stiffness. J Strength Cond Res. 2009;23(4):1148-1161.
    • Farmer's, suitcase and yoke carries credit the back, lats and hips
  78. Study McKenzie A, Crowley-McHattan Z, Meir R, Whitting J, Volschenk W (2022). Bench, Bar, and Ring Dips: Do Kinematics and Muscle Activity Differ?. Int J Environ Res Public Health. 2022;19(20):13211.
    • Reviewed, not used: dips keep chest and triceps both as prime movers, and the ring dip no extra chest
  79. Study McKenzie A, Crowley-McHattan Z, Meir R, Whitting J, Volschenk W (2022). Fatigue Increases Muscle Activations but Does Not Change Maximal Joint Angles during the Bar Dip. Int J Environ Res Public Health. 2022;19(21):14390.
    • Reviewed, not used: the bar dip works the chest and triceps
  80. Study Mendonça TP, Aidar FJ, Matos DG, et al. (2021). Force production and muscle activation during partial vs. full range of motion in Paralympic Powerlifting. PLoS One. 2021;16(10):e0257810.
    • Reviewed, not used: board, pin and floor presses keep the bench press shares
  81. Study Morin T, Doguet V, Nordez A, Caillet A, Lacourpaille L (2025). Minimal Role of Hamstring Hypertrophy in Strength Transfer Between Nordic Hamstring and Stiff-Leg Deadlift: A Blinded Randomized Controlled Trial. J Strength Cond Res. 2025;39(9):924-932.
    • Reviewed, not used: the stiff-leg deadlift grows the hamstrings
  82. Study Muyor JM, Rodríguez-Ridao D, Oliva-Lozano JM (2023). Comparison of Muscle Activity between the Horizontal Bench Press and the Seated Chest Press Exercises Using Several Grips. J Hum Kinet. 2023;87:23-34.
    • Reviewed, not used: the chest press machine keeps the bench press shares
  83. Study Nagao H, Ishii Y (2021). Characteristics of the Shrug Motion and Trapezius Muscle Activity During the Power Clean. J Strength Cond Res. 2021;35(12):3288-3295.
    • The Olympic pull credits the traps 0.9
  84. Review Oliva-Lozano JM, Muyor JM (2020). Core Muscle Activity During Physical Fitness Exercises: A Systematic Review. Int J Environ Res Public Health. 2020;17(12):4306.
    • Reviewed, not used: core muscle activity across fitness exercises
  85. Study Padovan R, Toninelli N, Longo S, Tornatore G, Esposito F, Cè E, et al. (2026). High-Density Surface Electromyography Excitation in Front vs. Back Overhead Press Prime Movers. J Hum Kinet. 2026;103:81-96.
    • Reviewed, not used: pressing in front of and behind the neck
  86. Study Paoli A, Gentil P, Moro T, Marcolin G, Bianco A (2017). Resistance Training with Single vs. Multi-joint Exercises at Equal Total Load Volume: Effects on Body Composition, Cardiorespiratory Fitness, and Muscle Strength. Front Physiol. 2017;8:1105.
    • Reviewed, not used: single-joint against multi-joint training
  87. Study Paoli A, Marcolin G, Petrone N (2009). The effect of stance width on the electromyographical activity of eight superficial thigh muscles during back squat with different bar loads. J Strength Cond Res. 2009;23(1):246-250.
    • Reviewed, not used: a sumo squat credits the adductors more than a back squat
  88. Study Patterson JM, Vigotsky AD, Oppenheimer NE, Feser EH (2015). Differences in unilateral chest press muscle activation and kinematics on a stable versus unstable surface while holding one versus two dumbbells. PeerJ. 2015;3:e1365.
    • Reviewed, not used: a single arm dumbbell press credits no obliques
  89. Study Paz GA, Almeida L, Ruiz L, Casseres S, Xavier G, Lucas J, et al. (2020). Myoelectric Responses of Lower-Body Muscles Performing Squat and Lunge Exercise Variations Adopting Visual Feedback With a Laser Sensor. J Sport Rehabil. 2020;29(8):1159-1165.
    • Reviewed, not used: squat and lunge activity with visual feedback
  90. Study Plotkin DL, Rodas MA, Vigotsky AD, McIntosh MC, Breeze E, Ubrik R, et al. (2023). Hip thrust and back squat training elicit similar gluteus muscle hypertrophy and transfer similarly to the deadlift. Front Physiol. 2023;14:1279170.
    • A hip thrust or glute bridge credits hamstrings 0.3 and quads 0.3
  91. Review Rabello R, Bertozzi F, Hauschild de Freitas IL, Molinari T, Roncada C, Sforza C, et al. (2024). Activation of the three deltoid muscle portions during common strengthening exercises: A systematic review. J Bodyw Mov Ther. 2024;40:1309-1325.
    • A chest fly credits the front delt as much as a bench press does, and more on an incline
  92. Study Rodríguez-Ridao D, Antequera-Vique JA, Martín-Fuentes I, Muyor JM (2020). Effect of Five Bench Inclinations on the Electromyographic Activity of the Pectoralis Major, Anterior Deltoid, and Triceps Brachii during the Bench Press Exercise. Int J Environ Res Public Health. 2020;17(19):7339.
    • An incline press keeps the front delt one step above a flat bench, not Primary
  93. Study Rosaci G, Nigro F, Cortesi M, Ciacci S, Bartolomei S, Fantozzi S (2025). Electromyographic Analysis of the Support Scale in Gymnastics and Its Related Preconditioning Strengthening Exercises. J Strength Cond Res. 2025;39(6):680-686.
    • A planche credits biceps 0.5 and chest 0.5
  94. Study Roth R, Donath L, Faude O, Cresswell AG (2020). Trunk muscle activity during different types of low weighted squat exercises in normal and forefoot standing conditions. J Sports Sci. 2020;38(24):2774-2781.
    • An overhead squat credits obliques 0.3
  95. Study Saeterbakken AH, Fimland MS (2013). Effects of body position and loading modality on muscle activity and strength in shoulder presses. J Strength Cond Res. 2013;27(7):1824-1831.
    • A dumbbell or kettlebell overhead press credits the triceps a smaller share than a barbell press
  96. Study Saeterbakken AH, Mo DA, Scott S, Andersen V (2017). The Effects of Bench Press Variations in Competitive Athletes on Muscle Activity and Performance. J Hum Kinet. 2017;57:61-71.
    • Reviewed, not used for grip width or the decline; with a second study, sets the incline triceps share
  97. Study Saeterbakken AH, Stien N, Pedersen H, Solstad TEJ, Cumming KT, Andersen V (2021). The Effect of Grip Width on Muscle Strength and Electromyographic Activity in Bench Press among Novice- and Resistance-Trained Men. Int J Environ Res Public Health. 2021;18(12):6444.
    • Reviewed for grip width: the basis for close grip triceps 0.7, not used for the wide grip
  98. Study Saeterbakken AH, van den Tillaar R, Fimland MS (2011). A comparison of muscle activity and 1-RM strength of three chest-press exercises with different stability requirements. J Sports Sci. 2011;29(5):533-538.
    • A dumbbell press credits the triceps a smaller share than a barbell or machine press
  99. Review Sahinis C, Amiridis IG, Enoka RM, Kellis E (2025). Differences in activation amplitude between semitendinosus and biceps femoris during hamstring exercises: A systematic and critical review with meta-analysis. J Sports Sci. 2025;43(11):1054-1069.
    • Reviewed, not used: which hamstring works in which exercise
  100. Study Santos PDG, Vaz JR, Correia PF, Valamatos MJ, Veloso AP, Pezarat-Correia P (2021). Intermuscular Coordination in the Power Clean Exercise: Comparison between Olympic Weightlifters and Untrained Individuals-A Preliminary Study. Sensors (Basel). 2021;21(5):1904.
    • Reviewed, not used: muscle synergies in the power clean
  101. Study Santos PDG, Vaz JR, Correia PF, Valamatos MJ, Veloso AP, Pezarat-Correia P (2020). Muscle Synergies Reliability in the Power Clean Exercise. J Funct Morphol Kinesiol. 2020;5(4):75.
    • Reviewed, not used: reliability of power clean muscle synergies
  102. Review Schoenfeld BJ, Grgic J, Haun C, Itagaki T, Helms ER (2019). Calculating Set-Volume for the Limb Muscles with the Performance of Multi-Joint Exercises: Implications for Resistance Training Prescription. Sports (Basel). 2019;7(7):177.
    • Crediting a compound lift to the muscles that help, not only the prime mover
  103. Study Serner A, Jakobsen MD, Andersen LL, Hölmich P, Sundstrup E, Thorborg K (2014). EMG evaluation of hip adduction exercises for soccer players: implications for exercise selection in prevention and treatment of groin injuries. Br J Sports Med. 2014;48(14):1108-1114.
    • A Copenhagen plank credits adductors 1
  104. Study Signorile JF, Rendos NK, Heredia Vargas HH, Alipio TC, Regis RC, Eltoukhy MM, et al. (2017). Differences in Muscle Activation and Kinematics Between Cable-Based and Selectorized Weight Training. J Strength Cond Res. 2017;31(2):313-322.
    • Reviewed, not used: cable against selectorized machine presses
  105. Study Solstad TE, Andersen V, Shaw M, Hoel EM, Vonheim A, Saeterbakken AH (2020). A Comparison of Muscle Activation between Barbell Bench Press and Dumbbell Flyes in Resistance-Trained Males. J Sports Sci Med. 2020;19(4):645-651.
    • Reviewed, not used: the one study finding less front delt in a fly than a bench press
  106. Study Tanimoto M, Arakawa H, Sato M, Nagano A (2023). Lateral Force and EMG Activity in Wide- and Narrow-Grip Bench Press in Various Conditions. Sports (Basel). 2023;11(8):154.
    • A close grip bench credits the triceps 0.7, not the 0.9 it had
  107. Study Trebs AA, Brandenburg JP, Pitney WA (2010). An electromyography analysis of 3 muscles surrounding the shoulder joint during the performance of a chest press exercise at several angles. J Strength Cond Res. 2010;24(7):1925-1930.
    • An incline press keeps the front delt one step above a flat bench, not Primary
  108. Study Uysal A, Karaduman B, Soslu R, Lök S, Govindasamy K, Tejaswi J, et al. (2026). Effects of grip variation on biceps brachii and brachioradialis electromyographic activity during concentric and eccentric phases of the barbell curl exercise. BMC Sports Sci Med Rehabil. 2026, online ahead of print.
    • Reviewed, not used: biceps and brachioradialis by contraction phase
  109. Study Vantrease WC, Townsend JR, Sapp PA, Henry RN, Johnson KD (2021). Maximal Strength, Muscle Activation, and Bar Velocity Comparisons Between Squatting With a Traditional or Safety Squat Bar. J Strength Cond Res. 2021;35(Suppl 1):S1-S5.
    • A specialty-bar squat credits the back squat's muscles
  110. Study Vigotsky AD, Harper EN, Ryan DR, Contreras B (2015). Effects of load on good morning kinematics and EMG activity. PeerJ. 2015;3:e708.
    • Reviewed, not used: good morning muscle activity by load
  111. Study Vissing K, Brink M, Lønbro S, Sørensen H, Overgaard K, Danborg K, et al. (2008). Muscle adaptations to plyometric vs. resistance training in untrained young men. J Strength Cond Res. 2008;22(6):1799-1810.
    • A jump credits adductors 0.4 and keeps hamstrings 0.5
  112. Study Wang Y, Zhao X, Zhang L, Gao X, Zheng Z, Wang S (2026). Unilateral low-load blood flow restriction vs. high-load training in the Bulgarian split squat: a randomized within-subject design on strength, hypertrophy, and asymmetry. Front Physiol. 2026;17:1786733.
    • Reviewed, not used: Bulgarian split squat training
  113. Study Welsch EA, Bird M, Mayhew JL (2005). Electromyographic activity of the pectoralis major and anterior deltoid muscles during three upper-body lifts. J Strength Cond Res. 2005;19(2):449-452.
    • A chest fly credits the front delt as much as a bench press does
  114. Study Youdas JW, Amundson CL, Cicero KS, Hahn JJ, Harezlak DT, Hollman JH (2010). Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or perfect-pullup rotational exercise. J Strength Cond Res. 2010;24(12):3404-3414.
    • Reviewed, not used: the chin-up and the pull-up
  115. Study Youdas JW, Baartman HE, Gahlon BJ, Kohnen TJ, Sparling RJ, Hollman JH (2020). Recruitment of Shoulder Prime Movers and Torso Stabilizers During Push-Up Exercises Using a Suspension Training System. J Sport Rehabil. 2020;29(7):993-1000.
    • A push up on rings credits the trunk and leaves the pressing muscles as they are
  116. Study Youdas JW, Boor MM, Darfler AL, Koenig MK, Mills KM, Hollman JH (2014). Surface electromyographic analysis of core trunk and hip muscles during selected rehabilitation exercises in the side-bridge to neutral spine position. Sports Health. 2014;6(5):416-421.
    • A side plank credits glutes 0.5 and abs 0.3
  117. Study Zebis MK, Skotte J, Andersen CH, Mortensen P, Petersen HH, Viskaer TC, et al. (2013). Kettlebell swing targets semitendinosus and supine leg curl targets biceps femoris: an EMG study with rehabilitation implications. Br J Sports Med. 2013;47(18):1192-1198.
    • A kettlebell swing keeps hamstrings 0.7

What counts as a hard set

  1. Study Lasevicius T, Ugrinowitsch C, Schoenfeld BJ, et al. (2018). Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy. Eur J Sport Sci. 2018;18(6):772-780.
    • A very long set of a movement you cannot add load to counts as less than a full set
  2. Study Morton RW, Oikawa SY, Wavell CG, et al. (2016). Neither load nor systemic hormones determine resistance training-mediated hypertrophy or strength gains in resistance-trained young men. J Appl Physiol. 2016;121(1):129-138.
    • A set counts the same whatever the load on it, when taken near failure
  3. Review Schoenfeld BJ, Grgic J, Van Every DW, Plotkin DL (2021). Loading Recommendations for Muscle Strength, Hypertrophy, and Local Endurance: A Re-Examination of the Repetition Continuum. Sports (Basel). 2021;9(2):32.
    • The near-failure "hard set" every counted working set is assumed to be

Recovery

  1. Study Damas F, Phillips SM, Libardi CA, et al. (2016). Resistance training-induced changes in integrated myofibrillar protein synthesis are related to hypertrophy only after attenuation of muscle damage. J Physiol. 2016;594(18):5209-5222.
    • Muscle damage from the same session shrinks as training goes on (the repeated-bout effect), so one fixed recovery timeline is a simplification
  2. Review Hooper SL, Mackinnon LT (1995). Monitoring overtraining in athletes. Recommendations. Sports Med. 1995;20(5):321-327.
    • Rating sleep, soreness, stress and fatigue each day as a self-reported read on recovery (the readiness sliders)
  3. Study MacDougall JD, Gibala MJ, Tarnopolsky MA, MacDonald JR, Interisano SA, Yarasheski KE (1995). The time course for elevated muscle protein synthesis following heavy resistance exercise. Can J Appl Physiol. 1995;20(4):480-486.
    • The Body Map recovery timeline (protein synthesis peaks around 24 hours and is back near baseline by about 36)

Training load (ACWR)

  1. Review Gabbett TJ (2016). The training-injury prevention paradox: should athletes be training smarter and harder?. Br J Sports Med. 2016;50(5):273-280.
    • Where the acute:chronic workload ratio comes from
  2. Study Gabbett TJ, Hulin B, Blanch P, Chapman P, Bailey D (2019). To Couple or not to Couple? For Acute:Chronic Workload Ratios and Injury Risk, Does It Really Matter?. Int J Sports Med. 2019;40(9):597-600.
    • The other side of the coupling argument
  3. Study Hulin BT, Gabbett TJ, Lawson DW, Caputi P, Sampson JA (2016). The acute:chronic workload ratio predicts injury: high chronic workload may decrease injury risk in elite rugby league players. Br J Sports Med. 2016;50(4):231-236.
    • The original case for the ratio, which the app cites and does not adopt as injury prediction
  4. Review Impellizzeri FM, Tenan MS, Kempton T, Novak A, Coutts AJ (2020). Acute:Chronic Workload Ratio: Conceptual Issues and Fundamental Pitfalls. Int J Sports Physiol Perform. 2020;15(6):907-913.
    • Why every load zone is worded as a description of load and never as injury risk
  5. Study Impellizzeri FM, Woodcock S, Coutts AJ, Fanchini M, McCall A, Vigotsky AD (2021). What Role Do Chronic Workloads Play in the Acute to Chronic Workload Ratio? Time to Dismiss ACWR and Its Underlying Theory. Sports Med. 2021;51(3):581-592.
    • A reanalysis finding a ratio built on a random chronic load is as associated with injury as the real one
  6. Commentary Lolli L, Batterham AM, Hawkins R, et al. (2019). Mathematical coupling causes spurious correlation within the conventional acute-to-chronic workload ratio calculations. Br J Sports Med. 2019;53(15):921-922.
    • Why the app shows the uncoupled ratio (this week left out of the baseline)
  7. Study Murray NB, Gabbett TJ, Townshend AD, Blanch P (2017). Calculating acute:chronic workload ratios using exponentially weighted moving averages provides a more sensitive indicator of injury likelihood than rolling averages. Br J Sports Med. 2017;51(9):749-754.
    • The EWMA ratio is more sensitive than the rolling one (cited for sensitivity only)
  8. Study Pritchard H, Barnes M, Keogh J, McGuigan M (2016). The effectiveness of Prilepin's chart for powerlifting strength improvements in resistance trained males. Poster, NSCA National Conference, New Orleans.
    • Where the Analytics intensity zones draw their lines: below 70, 70 to 80, 80 to 90 and 90 percent and up are the rows of Prilepin's chart. The zones use its boundaries only and quote none of its rep numbers
  9. Meta-analysis Qin W, Li R, Chen L (2025). Acute to chronic workload ratio (ACWR) for predicting sports injury risk: a systematic review and meta-analysis. BMC Sports Sci Med Rehabil. 2025;17(1):285.
    • The most recent pooled read on whether the ratio predicts injury
  10. Review Soligard T, Schwellnus M, Alonso JM, et al. (2016). How much is too much? (Part 1) International Olympic Committee consensus statement on load in sport and risk of injury. Br J Sports Med. 2016;50(17):1030-1041.
    • Consensus background on training load
  11. Commentary Williams S, West S, Cross MJ, Stokes KA (2017). Better way to determine the acute:chronic workload ratio?. Br J Sports Med. 2017;51(3):209-210.
    • The exponentially weighted (EWMA) version of the ratio shown beside the rolling one
  12. Commentary Windt J, Gabbett TJ (2019). Is it all for naught? What does mathematical coupling mean for acute:chronic workload ratios?. Br J Sports Med. 2019;53(16):988-990.
    • The coupled and uncoupled ratios, and how far apart they can drift

RPE and one-rep max estimates

  1. Method Brzycki M (1993). Strength testing: predicting a one-rep max from reps-to-fatigue. J Phys Educ Recreat Dance. 1993;64(1):88-90.
    • Why rep-based estimates are not trusted past 10 reps
  2. Method Epley B (1985). Poundage Chart. Boyd Epley Workout, Lincoln, NE.
    • The reps-only one-rep max estimate, used when a set carries no RPE
  3. Meta-analysis Halperin I, Malleron T, Har-Nir I, Androulakis-Korakakis P, Wolf M, Fisher J, Steele J (2022). Accuracy in Predicting Repetitions to Task Failure in Resistance Exercise: A Scoping Review and Exploratory Meta-analysis. Sports Med. 2022;52(2):377-390.
    • Why every one-rep max estimate in the app trusts an RPE only at 7 or harder
  4. Review Helms ER, Cronin J, Storey A, Zourdos MC (2016). Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training. Strength Cond J. 2016;38(4):42-49.
    • Using an RPE and rep count to read a percentage of your max
  5. Study LeSuer DA, McCormick JH, Mayhew JL, Wasserstein RL, Arnold MD (1997). The accuracy of prediction equations for estimating 1-RM performance in the bench press, squat, and deadlift. J Strength Cond Res. 1997;11(4):211-213.
    • Rep-based one-rep max formulas misestimate a max from a single reps-to-fatigue set (all seven tested underestimated the deadlift)
  6. Method Tuchscherer M (2008). The Reactive Training Manual (the reps by RPE to %1RM chart). Reactive Training Systems.
    • The chart behind RPE-based prescriptions, the RPE-aware one-rep max, and the 10-rep limit on estimates
  7. Study Zourdos MC, Klemp A, Dolan C, et al. (2016). Novel Resistance Training-Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve. J Strength Cond Res. 2016;30(1):267-275.
    • RPE as reps in reserve, which the RPE-aware one-rep max estimate is built on

Bodyweight movements

  1. Study Ebben WP, Wurm B, VanderZanden TL, et al. (2011). Kinetic Analysis of Several Variations of Push-Ups. J Strength Cond Res. 2011;25(10):2891-2894.
    • A push up moves about 64 percent of bodyweight (peak force on a force plate)
  2. Study Gouvali MK, Boudolos K (2005). Dynamic and Electromyographical Analysis in Variants of Push-Up Exercise. J Strength Cond Res. 2005;19(1):146-151.
    • Push up variants and their share of bodyweight (66.4 percent for a standard push up)
  3. Method Low S (n.d.). Estimates by the math: a general comparison of barbell squats to pistol squats. Eat Move Improve (online).
    • A pistol squat lifts about 88.5 percent of bodyweight
    • With Winter, the 0.90 bodyweight fraction the Strength Level pistol band is graded on
  4. Study Melrose D, Dawes J (2015). Resistance Characteristics of the TRX Suspension Training System at Different Angles and Distances from the Hanging Point. J Athl Enhancement. 2015;4(1).
    • Inverted and ring rows as a share of bodyweight, by body angle
  5. Study Suprak DN, Dawes J, Stephenson MD (2011). The Effect of Position on the Percentage of Body Mass Supported During Traditional and Modified Push-up Variants. J Strength Cond Res. 2011;25(2):497-503.
    • Incline, decline and knee push ups as a share of bodyweight
  6. Book Winter DA (2009). Biomechanics and Motor Control of Human Movement (segment mass tables). Wiley.
    • Summing body segment masses to estimate the share of you a movement lifts, where nobody has measured it

Bar speed

  1. Study González-Badillo JJ, Sánchez-Medina L (2010). Movement velocity as a measure of loading intensity in resistance training. Int J Sports Med. 2010;31(5):347-352.
    • Bar speed falls in a near-straight line as load rises, and a one-rep max has a typical speed (bench press about 0.17 m/s)
  2. Review Jovanović M, Flanagan EP (2014). Researched applications of velocity based strength training. J Aust Strength Cond. 2014.
    • Reading a one-rep max off a fitted load-velocity line at a per-lift threshold speed
  3. Meta-analysis Nagatani T, Latella C, Yang J, Kendall KL, Vial S, Comfort P, Drinkwater EJ, Haff GG (2026). The Effectiveness of Cluster vs. Rest-Redistribution Set Configurations to Maintain Movement Velocity During Resistance Training: A Systematic Review and Bayesian Network Meta-analysis. Sports Med Open. 2026;12(1).
    • Why a cluster set is used: rest inside the set keeps bar speed from falling as far as it does across the same reps done straight
  4. Study Pareja-Blanco F, Rodríguez-Rosell D, Sánchez-Medina L, et al. (2017). Effects of velocity loss during resistance training on athletic performance, strength gains and muscle adaptations. Scand J Med Sci Sports. 2017;27(7):724-735.
    • Velocity loss within a set as a fatigue signal: stopping at 20 percent loss matched 40 percent for squat strength with less fatigue, while 40 percent built more muscle

Meet scores and strength standards

  1. Method DOTS formula (2019). DOTS relative strength score for powerlifting. Formula coefficients (2019).
    • Relative strength score on the Meets chart, the share card and Strength Level
  2. Method ExRx.net (n.d.). Strength Standards. exrx.net.
    • Publisher of the Kilgore standards, the published tradition the Strength Level bands sit in. The bands are ours, not calculated from these tables
  3. Study Fahey TD (2026). Body-mass normalization of powerlifting performance: development and independent validation of sex- and age-specific regression-residual scores. Eur J Appl Physiol. 2026.
    • Why DOTS and IPF GL are the fairest of the meet scores: the least tied to bodyweight in 760,048 meet entries
    • Why Strength Level grades against a scaled bodyweight: a plain bodyweight multiple still correlates about 0.47 with body mass
  4. Study Flores FJ, Redondo JC (2020). Analysis of the percentage ratio between the weight lifted in the snatch and in the clean and jerk by international elite weightlifters. Int J Adv Res. 2020;8(4):901-905.
    • A consistency check between the two Olympic Elite bands: the snatch runs about 80 percent of the clean and jerk for men and 82 for women
    • The program wizard's check that a snatch is not lagging its clean and jerk (0.81, the midpoint of the two)
  5. Method International Powerlifting Federation (2020). IPF GL (Goodlift) points. IPF.
    • The official IPF score on the Meets chart
  6. Method International Weightlifting Federation (2025). Sinclair coefficients, 2025-2028 Olympiad (men's and women's tables). Published by the Alberta Weightlifting Association, hosted by the Polish Weightlifting Federation.
    • Weightlifting relative strength on the Meets chart, the meet form and Strength Level
  7. Method Kilgore L (2023). Strength Standard Tables (review draft for the book Barbell Sports). Kilgore Academy.
    • The published tradition the Strength Level bands sit in, and the tables they are measured against. The bands are ours, not calculated from these tables
  8. Study Latella C, Van den Hoek D, Teo WP (2018). Factors affecting powerlifting performance: an analysis of age- and weight-based determinants of relative strength. International Journal of Performance Analysis in Sport.
    • A second published comparison for the men's masters age factors: relative strength by age group in Powerlifting Australia competitors (comparison only)
  9. Dataset Meston E and contributors (n.d.). OpenWeightlifting meet results database (public domain). github.com/euanwm/OpenWeightlifting.
    • Checking the snatch and clean and jerk Advanced and Elite bands against what competitive weightlifters lift, and testing whether the bodyweight adjustment holds for those two lifts
    • Measuring how the snatch and clean and jerk change with age, from the US masters bands, for the age-adjusted Strength Level grade
  10. Study Montenegro S, Wicker P, Wiedenmann T, Rappelt L, Donath L (2026). Percentile-Based Normative Standards for Strength Assessment Beyond Linear Bodyweight Multipliers in Competitive Powerlifters. Sports Med Open. 2026;12(1):136.
    • Relative strength falls with bodyweight at every percentile (faster for women in the squat and bench), so Strength Level grades against a scaled bodyweight
  11. Dataset OpenPowerlifting project (n.d.). OpenPowerlifting meet results database (CC0). openpowerlifting.org.
    • Checking the Advanced and Elite bands against what competitive lifters lift
    • Measuring how strength scales with bodyweight, per sex, for the Strength Level adjustment
    • Measuring how strength changes with age, per sex, for the age-adjusted Strength Level grade
  12. Method The OpenPowerlifting Project (n.d.). AGE_COEFFICIENTS table, crates/coefficients/src/mcculloch.rs. gitlab.com/openpowerlifting/opl-data.
    • Cross-checking the junior age factors of the age-adjusted Strength Level grade against the Foster coefficients (comparison only; no factor was taken from it)
  13. Method Wilks R (2020). Wilks-2 relative strength coefficients (2020 revision). Formula coefficients (2020).
    • Wilks score on the Meets chart
  14. Method World Raw Powerlifting Federation (2017). McCulloch coefficients for Masters. WRPF, Moscow.
    • Cross-checking the masters age factors of the age-adjusted Strength Level grade against the coefficients masters powerlifting uses (comparison only; no factor was taken from it)

Trend lines

  1. Method Theil H; Sen PK (1968). Estimates of the Regression Coefficient Based on Kendall's Tau (with Theil 1950). J Am Stat Assoc. 1968;63(324):1379-1389.
    • The outlier-resistant trend line on every progress chart, and the plateau detector

Pre-built programs

  1. Method All Pro (bodybuilding.com forum poster); spreadsheet extended by tr3pid (n.d.). All Pro's Simple Beginner Routine. LiftVault spreadsheet (original at workout-calculator.com).
    • Three days of the same seven lifts at 100, 90 and 80 percent, the 8-to-12 rep ladder over five weeks, and the 10 percent step for a passed test
  2. Book Bromley A (2021). Peak Strength: Competitive Performance Roadmap (Bullmastiff, pp. 154-166). Self-published (Base Strength book 2); free excerpt on empire-barbell.com.
    • Bullmastiff: Base and Peak phases in three-week waves, the main-lift AMRAP that adds one percent of the max per rep over target, and volumizing variations
  3. Method Bui J (n.d.). PHUL Advanced (6 Day, 13 Week). LiftVault spreadsheet.
    • The 13-week, six-day powerbuilding tables off a real 1RM, with deloads in weeks 4 and 8, an eased week 12 and singles in week 13, and the 3 + AMRAP sets
  4. Method Campbell B (n.d.). PHUL Workout: Power Hypertrophy Upper Lower. Muscle & Strength.
    • PHUL: upper and lower power days at 3 to 5 reps, then upper and lower hypertrophy days at 8 to 12, with no percentages
    • Named as the program PHUL Advanced takes its idea from
  5. Method Candito J (n.d.). Candito 6 Week Strength Program. Candito Training HQ (free spreadsheet).
    • The six-week peaking block: conditioning, strength, a heavy week-5 top set and a week-6 double at 97 percent of a true 1RM
  6. Method Hadim M (n.d.). StrongLifts 5x5. stronglifts.com.
    • The A/B novice linear progression: squat every session, 5x5 (deadlift 1x5), adding 5 lb a workout (10 lb deadlift)
  7. Method LeFever C (n.d.). GZCLP: a linear progression derived from the GZCL Method. The Fitness Wiki (r/Fitness).
    • GZCLP: T1/T2/T3 tiers over a four-day rotation, the T1 ladder 5x3 -> 6x2 -> 10x1 and the T2 ladder 3x10 -> 3x8 -> 3x6
  8. Method LeFever C (2016). Jacked & Tan 2.0. Swole at Every Height (blog).
    • Jacked & Tan 2.0: two six-week blocks of daily rep maxes (10RM down to a single), drop sets off a training max then off the day's rep max, and Max Rep Sets
  9. Method LeFever C (2016). Volume Dependent Intensity Progression. Swole at Every Height (blog).
    • VDIP: max rep sets at 85 percent (T1) and 65 percent (T2) of a training max, and the Tiered Volume Goals that turn a lift's total reps into +10 lb, +5 lb, hold or a reduction next week
  10. Method LeFever C (2024). The Rippler (GZCL Free Compendium, October 9, 2024 update). GZCL Free Compendium (spreadsheet).
    • The Rippler: T1 "Two Up, One Down" off a 2RM, T2 three-week waves off a 5RM, T3 max rep sets off a 10RM with a three-weekly add by total reps, and the week 12 test
  11. Method LeFever C (2022). General Gainz Body Building. Swole at Every Height (blog).
    • General Gainz Body Building: a four-day superset body-part split run off rep maxes (a heavy 6RM with follow-up sets, then 15 to 20 rep T3 work), with no percentages
  12. Method Norton L (n.d.). PHAT: Power Hypertrophy Adaptive Training. biolayne.com.
    • PHAT: two power days and three hypertrophy days, speed sets at 65 to 70 percent of a 3 to 5 rep max, everything trained twice a week
  13. Method nSuns (Reddit user) (n.d.). nSuns 5/3/1 LP (5-day). Community spreadsheet; summarised on The Fitness Wiki.
    • The 5-day LP tables: a 9-set T1 and an 8-set T2 each day off a 90 percent training max, advanced weekly from the 1+ top set
  14. Method r/Fitness moderators (n.d.). r/Fitness Basic Beginner Routine. The Fitness Wiki (r/Fitness).
    • The A/B 3x5+ beginner routine, adding 2.5 lb upper and 5 lb lower per session, with the rep-out doubling the next jump
  15. Book Rippetoe M, Baker A (2014). Practical Programming for Strength Training (3rd edition). The Aasgaard Company.
    • The Texas Method: volume 5x5 at 90 percent of Friday, a light day at 80 percent of Monday, one heavy set of five on Friday, deadlift 1x5 on Monday and power cleans on Friday, with Glenn Pendlay credited as its origin
  16. Method Risley K (2026). Doug Hepburn Powerbuilding Methods. Lift Vault spreadsheet.
    • Doug Hepburn's power and pump phases: one weight held for the phase (80, 90 or 60 percent of a 1RM), a rep added each session from 8x2 to 8x3, 5 to 8 singles, 3x6 to 3x8 or 6x3 to 6x5, then 5 to 10 lb added
    • The add after each phase, 10 lb on the bar for squat and deadlift and 5 lb for bench and press
  17. Method Risley K (2026). Russian Squat Program + Routine Spreadsheet (Original and Masters Versions). Lift Vault spreadsheet.
    • The Russian Squat Routine's six-week, three-day grid at 80 percent of a 1RM or more (6x2 alternating with 6x3 up to 6x6, then 5x5 at 85, 4x4 at 90, 3x3 at 95, 2x2 at 100) ending on a max attempt at 105 to 110 percent, and the spreadsheet's three-lift version with its bench and deadlift grid and back extension
    • The Masters version: eight weeks, two days, each session opening with 3 at 60 and 2 at 70 percent, day 1 at 6x2 and day 2 climbing to a single at 100 with optional attempts at 105 and 110
  18. Method Risley K (2026). Lyle McDonald Generic Bulking Routine - Hypertrophy. Lift Vault spreadsheet.
    • The Generic Bulking Routine: four days, lower Monday and Thursday, upper Tuesday and Friday, main lifts 3 to 4 sets of 6 to 8, secondary 2 to 3 of 10 to 12, arm work 1 to 2 of 12 to 15, rest 3 minutes, 2 minutes and 90 seconds, an eight-week grid then a two-week deload, and 5 lb added on squat, bench and row once every set reaches 8
  19. Method Sheiko BI (n.d.). Sheiko powerlifting method and numbered routines. Method; set out in English in Sheiko BI, Powerlifting: Foundations and Methods (2018).
    • The preparatory cycle built to his method: competition lifts nearly every day, 50 to 85 percent of a competition best, sets of two to five, walked-up warm-ups
  20. Book Smith CW (2012). The Juggernaut Method 2.0: Strength, Speed, and Power for Every Athlete. Juggernaut Training Systems (e-book).
    • The Juggernaut Method: four waves of 10s, 8s, 5s and 3s, each run as accumulation, intensification, realization and deload, off a 90 percent training max
  21. Method Smolov S (n.d.). Smolov squat routine (base mesocycle), and the Smolov Jr compression. Soviet coaching method; popularised in English in Powerlifting USA (2001).
    • The base mesocycle (4x9, 5x7, 7x5, 10x3 at 70 to 85 percent of a true 1RM) and Smolov Jr (6x6, 7x5, 8x4, 10x3), with the published pound jumps turned into percentage steps
  22. Book Starr B (1976). The Strongest Shall Survive: Strength Training for Football. Fitness Products Ltd..
    • The 5x5 lineage StrongLifts is described as building on (history only; no number comes from it)
  23. Method u/Cammorak (n.d.). Dumbbell Stopgap. r/Fitness, archived on The Fitness Wiki.
    • The A/B dumbbell routine run as a double progression: three sets up to ten reps, then the next dumbbell
  24. Method u/gregariousHermit (n.d.). Dumbbell Stopgap PPL. r/Fitness, archived on The Fitness Wiki.
    • The six-day dumbbell push/pull/legs, three sets up to twelve reps then the next dumbbell
  25. Method u/m092 (Concept Wednesday); r/bodyweightfitness wiki (n.d.). The Minimalist Routine. r/bodyweightfitness wiki.
    • The four-exercise circuit (walking lunges, push-ups, rows, plank shoulder taps), two to six rounds, 8 to 10 reps as the bar for a harder variation
  26. Method u/Metallicdpa (n.d.). A Linear Progression Based PPL Program for Beginners. r/Fitness, archived on The Fitness Wiki.
    • The six-day linear-progression PPL: a heavy barbell 5+ lift each day progressed every session, then 8 to 12 rep accessories
  27. Book Wendler J (2009). 5/3/1: The Simplest and Most Effective Training System to Increase Raw Strength. Self-published (Jim Wendler LLC).
    • The 5/3/1 program: the four-week wave, percentages of a training max set at 90 percent, the AMRAP top set, and the per-cycle increments (5 lb upper, 10 lb lower)
    • Boring But Big: 5x10 at 50 percent after the main work
    • The training max and AMRAP progression nSuns 531 LP descends from
  28. Method Wendler J (program); r/Fitness wiki (page) (n.d.). 5/3/1 for Beginners. The Fitness Wiki (r/Fitness), companion page to Wendler's own article.
    • The 5/3/1 for Beginners template: two main lifts a day over three-week cycles, First Set Last 5x5, and 5 lb upper / 10 lb lower training-max increments

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