Untrained men trained for eight weeks in a low, intermediate or high repetition-maximum zone. Maximal strength improved most in the low-repetition group, repetitions at a submaximal load improved most in the high-repetition group, and only the low and intermediate zones produced fibre hypertrophy.

• Campos GE, Luecke TJ, Wendeln HK, Toma K, Hagerman FC, Murray TF, Ragg KE, Ratamess NA, Kraemer WJ, Staron RS. (2002). Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. View source

A review of the repetition continuum argues that the conventional mapping of heavy loads to strength, moderate loads to hypertrophy and light loads to endurance is not fully supported by current research. The authors propose instead that muscular adaptations can be obtained, and in some cases optimised, across a wide spectrum of loading zones.

• 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. View source

Men trained one limb at 20% of one-rep max and the contralateral limb at 40, 60 or 80% with volume load matched over twelve weeks. All loads increased strength and cross-sectional area, but the 20% condition was suboptimal for both while 80% was clearly superior for strength and size.

• Lasevicius T, Ugrinowitsch C, Schoenfeld BJ, Roschel H, Tavares LD, De Souza EO, Laurentino G, Tricoli V. (2018). Effects of different intensities of resistance training with equated volume load on muscle strength and hypertrophy View source

Well-trained men were randomly assigned to a split routine training each muscle once a week or a whole-body routine training each muscle five days a week, with volume matched. One-rep-max strength changes were the same, while the higher-frequency routine produced greater muscle thickness in the forearm flexors and vastus lateralis.

• Zaroni RS, Brigatto FA, Schoenfeld BJ, Braz TV, Benvenutti JC, Germano MD, Marchetti PH, Aoki MS, Lopes CR. (2019). High Resistance-Training Frequency Enhances Muscle Thickness in Resistance-Trained Men View source

A systematic review and meta-analysis restricted to well-trained populations found no clear difference in maximal strength development between training frequencies over six to twelve weeks. The authors suggest volume can therefore be distributed across shorter, more frequent sessions rather than condensed into one or two.

• Cuthbert M, Haff GG, Arent SM, Ripley N, McMahon JJ, Evans M, Comfort P. (2021). Effects of Variations in Resistance Training Frequency on Strength Development in Well-Trained Populations and Implications for In-Season Athlete Training: A Systematic Review and Meta-analysis View source

A meta-analysis of twenty-five studies on weekly training frequency found no significant difference between higher and lower frequencies once weekly volume was equated, including in resistance-trained participants and for both upper and lower body. Non-volume-equated studies favoured higher frequency only modestly.

• Schoenfeld BJ, Grgic J, Krieger J. (2019). How many times per week should a muscle be trained to maximize muscle hypertrophy? A systematic review and meta-analysis of studies examining the effects of resistance training frequency. View source

A meta-analysis of 157 randomised trials modelled resistance training dosage as sets times repetitions times exercises times intensity times frequency times duration and found a non-linear dose-response for strength. Increasing dosage beyond the identified plateau did not maintain or increase the rate at which strength developed.

• Lyristakis P, Wundersitz D, Cousins S, Huynh M, Zadow E, Gordon BA. (2026). The Influence of Individual Resistance Training Variables on Muscle Strength: A Systematic Review and Meta-analysis. View source

Retrospective growth modelling of training records from a large sample undergoing once-weekly single-set training to momentary failure found strength gains trending asymptotically, reaching a practical plateau by roughly one to two years. Substantial gains still accrued, around 30 to 50% in the first year.

• Steele J, Fisher JP, Giessing J, Androulakis-Korakakis P, Wolf M, Kroeske B, Reuters R. (2023). Long-Term Time-Course of Strength Adaptation to Minimal Dose Resistance Training Through Retrospective Longitudinal Growth Modeling. View source

Adults trained three days a week for sixteen weeks and then dropped to either one third or one ninth of that dose for a further thirty-two weeks. Both maintenance doses preserved fibre hypertrophy in young adults but not in older ones, while strength was largely retained even through complete detraining.

• Bickel CS, Cross JM, Bamman MM. (2011). Exercise dosing to retain resistance training adaptations in young and older adults. View source

Untrained men trained for eight weeks and then dropped to either one or two sessions per week with volume load roughly halved. Both reduced-training groups held their half-squat one-rep max and quadriceps cross-sectional area, while the group that stopped entirely lost both.

• Tavares LD, de Souza EO, Ugrinowitsch C, Laurentino GC, Roschel H, Aihara AY, Cardoso FN, Tricoli V. (2017). Effects of different strength training frequencies during reduced training period on strength and muscle cross-sectional area. View source

A multi-experiment study of powerlifting athletes and coaches concluded that a minimum effective dose approach means 3 to 6 working sets of one to five repetitions each week per powerlift. Those sets were spread across 1 to 3 sessions per week using loads above 80% of one-rep max.

• 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. View source

A systematic review and meta-analysis of the minimum effective training dose in resistance-trained men found that a single set performed between one and three times per week was enough to produce significant one-rep-max gains. Loads of roughly 70 to 85% of one-rep max taken to a high intensity of effort produced suboptimal but real squat and bench press increases.

• 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. View source

Resistance-trained individuals squatting more than twice bodyweight trained lower body at twelve, eighteen or twenty-four weekly sets for eight weeks. Muscle thickness and fat-free mass did not differ by weekly set number, and the middle dose produced the largest back-squat one-rep-max increase.

• Aube D, Wadhi T, Rauch J, Anand A, Barakat C, Pearson J, Bradshaw J, Zazzo S, Ugrinowitsch C, De Souza EO. (2022). Progressive Resistance Training Volume: Effects on Muscle Thickness, Mass, and Strength Adaptations in Resistance-Trained Individuals View source

Resistance-trained males either held lower-limb weekly set volume constant or added four or six sets per week every two weeks across twelve weeks. Both progression groups gained more back-squat one-rep-max strength than the constant group, and the six-set progression beat the four-set one, while hypertrophy did not differ between groups.

• Enes A, DE Souza EO, Souza-Junior TP. (2024). Effects of Different Weekly Set Progressions on Muscular Adaptations in Trained Males: Is There a Dose-Response Effect? View source

Resistance-trained men performed one, three or five sets per exercise per session for eight weeks. Strength and endurance rose equally in all three groups, while hypertrophy followed a dose-response with increasingly greater gains at higher volumes.

• Schoenfeld BJ, Contreras B, Krieger J, Grgic J, Delcastillo K, Belliard R, Alto A. (2019). Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men View source

A meta-analysis of weekly set volume and strength gain found a graded dose-response, with medium and high weekly set counts more effective than low ones and low weekly sets producing the smallest pre-to-post difference. For well-trained individuals the authors judged either a medium or a high weekly set dose appropriate.

• Ralston GW, Kilgore L, Wyatt FB, Baker JS. (2017). The Effect of Weekly Set Volume on Strength Gain: A Meta-Analysis. View source

A review of the session rating-of-perceived-exertion method found the validity, reliability and internal consistency of the method confirmed across several sports and physical activities, in men and women, across age categories and expertise levels. The authors note some recommend combining it with a physiological measure such as heart rate.

• Haddad M, Stylianides G, Djaoui L, Dellal A, Chamari K. (2017). Session-RPE Method for Training Load Monitoring: Validity, Ecological Usefulness, and Influencing Factors View source

A systematic review of longitudinal studies on training load and fatigue markers found athletes at increased risk of injury and illness at key stages of training and competition, including periods of training load intensification and periods of accumulated load. The authors note wide disagreement in how load, fatigue, injury and illness are defined across the literature.

• Jones CM, Griffiths PC, Mellalieu SD. (2017). Training Load and Fatigue Marker Associations with Injury and Illness: A Systematic Review of Longitudinal Studies View source

A cross-sectional survey of competitive resistance-trained athletes found that most respondents had experienced an unexplained decrease in performance, usually lasting between one week and one month, with general fatigue the most frequent symptom. In the large majority of cases the episode coincided with non-training stressors, and the most severe cases were more often in athletes training to muscle failure.

• Grandou C, Wallace L, Coutts AJ, Bell L, Impellizzeri FM. (2021). Symptoms of Overtraining in Resistance Exercise: International Cross-Sectional Survey. View source

A systematic review of attempts to induce overreaching or overtraining through resistance exercise concluded that a lack of standardised methodology prevents consistent diagnosis. No marker other than a sustained decrease in performance has been established as a reliable indicator.

• Grandou C, Wallace L, Impellizzeri FM, Allen NG, Coutts AJ. (2020). Overtraining in Resistance Exercise: An Exploratory Systematic Review and Methodological Appraisal of the Literature. View source

A scoping review of overreaching and overtraining in strength sports found that short periods of high-volume or high-intensity training can produce functional overreaching, while chronic high volume or intensity can produce non-functional overreaching. It found minimal evidence that true overtraining syndrome has occurred in these populations.

• Bell L, Ruddock A, Maden-Wilkinson T, Rogerson D. (2020). Overreaching and overtraining in strength sports and resistance training: A scoping review. View source

Untrained young men had their limbs randomly assigned to continuous training or to a condition where weekly sets and frequency were cut at the midpoint and endpoint of an eight-week program. Muscle thickness and strength-endurance rose the same in both, with no time by condition interaction.

• Pancar Z, Ilhan MT, Darendeli MK, Karaca B, Ikidag MA, Tasdogan AM, Ulema MS, Alkhamees NH, Al-Mhanna SB, Batrakoulis A. (2026). Effects of deload periods in resistance training on muscle hypertrophy and strength endurance in untrained young men using a randomized within subject design. View source

A position stand on progression models recommends that intermediate and advanced lifters use a wider loading range with eventual emphasis on heavy loading, taken with 3 to 5 minute rest periods between sets at a moderate contraction velocity.

• American College of Sports Medicine. (2009). American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. View source

A systematic review with Bayesian meta-analysis of inter-set rest and hypertrophy found a small hypertrophic benefit to rest intervals longer than 60 s, probably mediated by preserved volume load. It detected no appreciable further difference in hypertrophy beyond 90 s.

• Singer A, Wolf M, Generoso L, Arias E, Delcastillo K, Echevarria E, Martinez A, Androulakis Korakakis P, Refalo MC, Swinton PA, Schoenfeld BJ. (2024). Give it a rest: a systematic review with Bayesian meta-analysis on the effect of inter-set rest interval duration on muscle hypertrophy View source

Fifteen men trained each arm on a cable curl with the shoulder either flexed or extended for ten weeks, matched for resistance profile. Muscle thickness and one-rep-max strength rose in both conditions with no significant differences at proximal, mid or distal regions of the biceps brachii or in the brachialis.

• Attarieh P, Nunes JP, Khani S, Negahdar S, Goli A, Nazarirad H, Nazarirad S, Mojtahedi S, Nosaka K, Soori R. (2025). Comparison Between Shoulder Flexed and Extended Positions in Elbow Flexion Resistance Training on Regional Hypertrophy and Maximum Strength: Preacher versus Bayesian Cable Curls. View source

Recreationally trained women performed nine weeks of either inclined biceps curls or preacher curls. Only the preacher curl group grew significantly, at the distal measurement site, and no statistically significant differences appeared between regions when analysed by group or region.

• Zabaleta-Korta A, Fernández-Peña E, Torres-Unda J, Francés M, Zubillaga A, Santos-Concejero J. (2023). Regional Hypertrophy: The Effect of Exercises at Long and Short Muscle Lengths in Recreationally Trained Women. View source

A Bayesian meta-analysis of twelve studies on mean muscle length during training found trivial differences in regional hypertrophy between proximal, mid-belly and distal sites. Training at longer muscle lengths showed an increasing trend toward distal sites, but the authors caution the shorter and longer conditions differed by only a small average muscle length.

• Varovic D, Wolf M, Schoenfeld BJ, Steele J, Grgic J, Mikulic P. (2025). Does Muscle Length Influence Regional Hypertrophy? A Systematic Review and Meta-Analysis. View source

A Bayesian meta-analysis of range of motion found a trivial standardised effect favouring full range over partial range across hypertrophy, strength, power and body-composition outcomes. Sub-group analysis suggested a hypertrophy benefit to partial range training at long muscle lengths, and a specificity effect whereby training in the range being tested produced greater strength adaptation.

• Wolf M, Androulakis-Korakakis P, Fisher J, Schoenfeld B, Steele J (2023). Partial Vs Full Range of Motion Resistance Training: A Systematic Review and Meta-Analysis View source

Rugby players completed eight weeks of volume-load-matched lower-body training differing only in whether the main exercise was a bilateral back squat or a unilateral step-up. Both groups improved their trained exercise and also showed transfer to the untrained one.

• Appleby BB, Cormack SJ, Newton RU. (2019). Specificity and Transfer of Lower-Body Strength: Influence of Bilateral or Unilateral Lower-Body Resistance Training. View source

A meta-analysis of nine studies found no difference in muscle hypertrophy between unilateral and bilateral resistance training, while bilateral training produced greater bilateral strength and unilateral training greater unilateral strength. The authors describe the strength result as following the principle of specificity.

• Kassiano W, Nunes JP, Costa B, Ribeiro AS, Loenneke JP, Cyrino ES. (2025). Comparison of Muscle Growth and Dynamic Strength Adaptations Induced by Unilateral and Bilateral Resistance Training: A Systematic Review and Meta-analysis. View source

Resistance-trained men completed eight weeks of identical programming differing only in whether the squat, bench press, prone bench pull and shoulder press used barbells or machines. Strength and cross-sectional area rose similarly in both, with no difference in joint discomfort.

• 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. View source

A meta-analysis of thirteen studies comparing free-weight and machine-based strength training found strength changes specific to the modality tested, with no differences between modalities in direct comparison for dynamic strength, isometric strength, jump performance or hypertrophy. The authors conclude the choice comes down to individual preference and goals.

• Haugen ME, Vårvik FT, Larsen S, Haugen AS, van den Tillaar R, Bjørnsen T. (2023). Effect of free-weight vs. machine-based strength training on maximal strength, hypertrophy and jump performance - a systematic review and meta-analysis. View source

A position stand on progression models recommends sequencing exercises to preserve exercise intensity, placing large muscle group work before small, multiple-joint before single-joint, and higher-intensity before lower-intensity work.

• American College of Sports Medicine. (2009). American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. View source

A review of exercise order found that total repetitions, and therefore volume, are greater when an exercise is placed at the beginning of a session regardless of how much muscle mass it involves. The authors recommend ordering exercises by priority of importance to the training goal rather than by muscle group size.

• Simão R, de Salles BF, Figueiredo T, Dias I, Willardson JM. (2012). Exercise order in resistance training. View source

A meta-analysis of eleven exercise-order studies found no overall difference in strength between orders, but strength gains in a given exercise favoured performing that exercise at the start of the session. Hypertrophy was unaffected by order.

• Nunes JP, Grgic J, Cunha PM, Ribeiro AS, Schoenfeld BJ, de Salles BF, Cyrino ES. (2021). What influence does resistance exercise order have on muscular strength gains and muscle hypertrophy? A systematic review and meta-analysis. View source

Strength-trained men completed a crossover trial in which two training blocks were each followed by a taper week with the same volume reduction but either raised or lowered intensity. The taper improved power in both conditions, with the higher-intensity taper tending to produce the more favourable strength and power changes.

• Pritchard HJ, Barnes MJ, Stewart RJ, Keogh JW, McGuigan MR. (2019). Higher- Versus Lower-Intensity Strength-Training Taper: Effects on Neuromuscular Performance. View source

Powerlifters were matched on relative strength and randomly assigned to an overreach week followed by either a one-week step taper or a three-week exponential taper. The step taper favoured skeletal muscle adaptations while the exponential taper appeared to favour neuromuscular performance.

• Travis SK, Zwetsloot KA, Mujika I, Stone MH, Bazyler CD. (2021). Skeletal Muscle Adaptations and Performance Outcomes Following a Step and Exponential Taper in Strength Athletes. View source

Interviews with elite raw powerlifters concluded that lifters benefit from continuing to strength train before an important event with reduced volume and maintained intensity. Only exercises that directly assist competition performance were kept in the program during the taper.

• Pritchard HJ, Tod DA, Barnes MJ, Keogh JW, McGuigan MR. (2016). Tapering Practices of New Zealand's Elite Raw Powerlifters. View source

Powerlifters completing a peaking block finished with a one-week step taper and then either 2 or 4 days of complete training cessation. Both maintained or improved maximal strength, with bench press and competition total rising after the shorter cessation.

• Burke BI, Carroll KM, Travis SK, Stone ME, Stone MH. (2023). Two Days Versus Four Days of Training Cessation Following a Step-Taper in Powerlifters. View source

Elite raw powerlifters reported cutting training volume by 58.9% during the taper while holding intensity. Surveyed weightlifters cut volume by 43.1%, strongman athletes by 45.5%, and Highland Games athletes by 34%.

• Pritchard HJ, Tod DA, Barnes MJ, Keogh JW, McGuigan MR. (2016). Tapering Practices of New Zealand's Elite Raw Powerlifters. View source
• Winwood PW, Keogh JWL, Travis SK, Pritchard HJ. (2023). The Tapering Practices of Competitive Weightlifters. View source
• Winwood PW, Dudson MK, Wilson D, Mclaren-Harrison JKH, Redjkins V, Pritchard HJ, Keogh JWL. (2018). Tapering Practices of Strongman Athletes. View source
• Winwood PW, Keogh JWL, Travis SK, Grieve I, Pritchard HJ. (2024). The Training and Tapering Practices of Highland Games Heavy Event Athletes. View source

Surveys of competitive weightlifters, strongman competitors and Highland Games heavy event athletes report mean taper lengths of 8.0, 8.6 and 5.2 days respectively. Step and linear tapers were the models these athletes used most.

• Winwood PW, Keogh JWL, Travis SK, Pritchard HJ. (2023). The Tapering Practices of Competitive Weightlifters. View source
• Winwood PW, Dudson MK, Wilson D, Mclaren-Harrison JKH, Redjkins V, Pritchard HJ, Keogh JWL. (2018). Tapering Practices of Strongman Athletes. View source
• Winwood PW, Keogh JWL, Travis SK, Grieve I, Pritchard HJ. (2024). The Training and Tapering Practices of Highland Games Heavy Event Athletes. View source

A review of peaking for powerlifting performance reports that strength athletes routinely taper or stop training before competition, but that the evidence base for how to do it in strength and power sport is thin and largely borrowed from endurance sport. The authors describe practitioners as working by trial and error rather than from an established protocol.

• Travis SK, Mujika I, Gentles JA, Stone MH, Bazyler CD. (2020). Tapering and Peaking Maximal Strength for Powerlifting Performance: A Review. View source

Men grouped by relative squat strength completed eleven weeks of block periodization. Every group improved, but percent change favoured the weakest group by a large to very large margin while the strongest group produced the highest absolute loaded jump heights.

• Wetmore AB, Moquin PA, Carroll KM, Fry AC, Hornsby WG, Stone MH. (2020). The Effect of Training Status on Adaptations to 11 Weeks of Block Periodization Training. View source

Previously untrained participants had their legs randomized to progress overload either by adding load or by adding repetitions over ten weeks. Both routes produced the same increases in one-rep-max leg extension strength and vastus lateralis cross-sectional area.

• Chaves TS, Scarpelli MC, Bergamasco JGA, Silva DGD, Medalha Junior RA, Dias NF, Bittencourt D, Carello Filho PC, Angleri V, Nóbrega SR, Roberts MD, Ugrinowitsch C, Libardi CA. (2024). Effects of Resistance Training Overload Progression Protocols on Strength and Muscle Mass. View source

A position stand on progression models recommends that when training at a specific repetition-maximum load, a 2 to 10% increase in load be applied once the lifter can perform the current workload for one to two repetitions beyond the target. It frames progressive overload as a triggered step rather than a fixed weekly increase.

• American College of Sports Medicine. (2009). American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. View source

In volume-equated programs, undulating periodization produced greater one-rep-max gains than linear periodization, but a subgroup analysis showed this held only for trained individuals. Previously untrained lifters gained the same from either model, and hypertrophy did not differ.

• Moesgaard L, Beck MM, Christiansen L, Aagaard P, Lundbye-Jensen J. (2022). Effects of Periodization on Strength and Muscle Hypertrophy in Volume-Equated Resistance Training Programs: A Systematic Review and Meta-analysis. View source

A systematic review of subjective and objective autoregulation methods found that every autoregulation protocol it reviewed increased one-rep-max strength, with effect sizes ranging from small to large. Subjective methods such as reps-in-reserve RPE and flexible undulating periodization and objective methods such as velocity targets were both effective.

• Larsen S, Kristiansen E, van den Tillaar R. (2021). Effects of subjective and objective autoregulation methods for intensity and volume on enhancing maximal strength during resistance-training interventions: a systematic review. View source

Amateur rugby players completed matched training blocks with intensity prescribed either from barbell velocity or from rating of perceived exertion. Both improved squat, bench press and countermovement jump, and the velocity-prescribed block produced the larger improvements.

• Shattock K, Tee JC. (2022). Autoregulation in Resistance Training: A Comparison of Subjective Versus Objective Methods. View source

Resistance-trained men followed a mixed-session periodized program for ten weeks either with or without a perceived-recovery scale adjusting daily volume. The autoregulated group accumulated more total volume but gained no more muscle thickness, strength or power.

• Bartolomei S, Francesco L, Latini D, Hoffman JR. (2024). Autoregulation Does Not Provide Additional Benefits to a Mixed Session Periodized Resistance Training Program in Trained Men. View source

A meta-analysis comparing autoregulated load prescription with percentage-based prescription found no significant difference in one-rep-max strength. Within the same review, velocity-loss thresholds at or below 25% favoured strength while thresholds above 20 to 25% favoured hypertrophy.

• Hickmott LM, Chilibeck PD, Shaw KA, Butcher SJ. (2022). The Effect of Load and Volume Autoregulation on Muscular Strength and Hypertrophy: A Systematic Review and Meta-Analysis. View source

Cardiac rehabilitation patients were randomly assigned to load prescribed by a reps-in-reserve rating of perceived exertion or by a percentage of estimated one-rep max, with everything else matched. Strength rose in both groups with no between-group difference and trivial effect sizes either way.

• Gismondi A, Iellamo F, Caminiti G, Sposato B, Gregorace E, D'Antoni V, Di Biasio D, Vadalà S, Franchini A, Mancuso A, Morsella V, Volterrani M. (2024). Rate of Perceived Exertion Based on Repetitions in Reserve Versus Percentage of One-Repetition Maximum for Resistance Training Prescription in Cardiac Rehabilitation: A Pilot Study. View source

A methods review argues that using reps in reserve on its own assumes identical RIR values correspond to equivalent physiological stimuli across different repetition ranges and intensities, an assumption that does not necessarily hold. It proposes a proportion-based level of effort, the share of a set's repetition capacity actually used, as a more complete description.

• Pareja-Blanco F, Loturco I. (2026). Level of Effort: A Practical Approach for Resistance Training Monitoring and Prescription. View source

A rating-of-perceived-exertion scale defined by how many repetitions remain at the end of a set is proposed as a more precise tool than a session-level rating. It adjusts load automatically to match the lifter's capability set to set and gauges intensity better at near-limit loads.

• Helms ER, Cronin J, Storey A, Zourdos MC. (2016). Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training View source

In a randomized crossover comparing percentage-based, RPE, reps-in-reserve and velocity-based prescription at the same relative load, percentage-based prescription regularly drove sets to failure while reps-in-reserve and velocity-based prescription preserved training volume. No condition differed in next-day neuromuscular fatigue or soreness.

• Cowley N, Nicholson V, Timmins R, Munteanu G, Wood T, García-Ramos A, Owen C, Weakley J. (2025). The Effects of Percentage-Based, Rating of Perceived Exertion, Repetitions in Reserve, and Velocity-Based Training on Performance and Fatigue Responses. View source

Older adults asked to stop at 2 and 4 reps in reserve underestimated the repetitions they had left by 2.1 and 1.6 reps, while a 6-rep-in-reserve target was accurate. The authors conclude that predicted RIR may lack precision for prescribing load but remains useful for monitoring volume.

• Gómez-Redondo P, Alcazar J, Valenzuela PL, Ara I, Alegre LM, Mañas A. (2025). Validity of repetitions in reserve for prescribing resistance exercise in older adults. View source

Experienced and novice lifters estimated 3 and 1 reps in reserve in the back squat at 70% of one-rep max with no difference in accuracy between the groups, corroborated objectively by mean propulsive velocity and rating of perceived exertion. The authors suggest familiarity with high-effort sets matters more than years of training.

• Droguett FAB, Festa RR, Quintana NAT, Gomez-Lopez J, Ojeda ÁH, Farias-Valenzuela C, Giakoni-Ramírez F, Jofré-Saldía E. (2025). Objective Accuracy in Estimating Repetitions in Reserve in the Back Squat: An Analysis between Experienced vs. Novice Subjects. View source

A series of meta-regressions treating proximity to failure as a continuous variable in reps in reserve found that strength gains were similar across a wide range of RIR, while muscle hypertrophy improved as sets were terminated closer to failure. The authors conclude the optimal proximity to failure may differ between the two outcomes.

• Robinson ZP, Pelland JC, Remmert JF, Refalo MC, Jukic I, Steele J, Zourdos MC. (2024). Exploring the Dose-Response Relationship Between Estimated Resistance Training Proximity to Failure, Strength Gain, and Muscle Hypertrophy: A Series of Meta-Regressions View source

Evidence on minimal effective dosing indicates that meaningful strength can be gained and existing muscle maintained with relatively low weekly volumes once a training base exists, so a small number of hard weekly sets per muscle can sustain progress during busy periods. Maintenance requires far less volume than continued maximal growth.

• Iversen VM, Norum M, Schoenfeld BJ, Fimland MS (2021). No Time to Lift? Designing Time-Efficient Training Programs for Strength and Hypertrophy: A Narrative Review View source

A systematic review and meta-analysis comparing superset to traditional resistance-training prescriptions found that supersets substantially reduce total training time and raise training density while producing largely comparable chronic adaptations, alongside higher acute metabolic and perceptual demand. Pairing exercises can save time without clearly compromising outcomes.

• Zhang X, Weakley J, Li H, Li Z (2025). Superset Versus Traditional Resistance Training Prescriptions: A Systematic Review and Meta-analysis Exploring Acute and Chronic Effects on Mechanical, Metabolic, and Perceptual Variables View source

A narrative review on time-efficient training concluded that trainees short on time can preserve strength and hypertrophy by emphasizing multi-joint exercises, using techniques such as supersets, drop sets, and shorter rest to compress sessions, and that a reduced volume can maintain gains once a base is built. Efficiency comes from prioritizing high-yield exercises and set structures.

• Iversen VM, Norum M, Schoenfeld BJ, Fimland MS (2021). No Time to Lift? Designing Time-Efficient Training Programs for Strength and Hypertrophy: A Narrative Review View source

A meta-analysis of repetition duration found that hypertrophy is similar across a wide range of lifting tempos, from roughly 0.5 to 8 seconds per repetition, and that very slow tempos offer no advantage and can reduce the load or volume that can be handled. Time under tension per se is not a primary hypertrophy driver within normal ranges.

• Schoenfeld BJ, Ogborn D, Krieger JW (2015). Effect of Repetition Duration During Resistance Training on Muscle Hypertrophy: A Systematic Review and Meta-Analysis View source

A review of warm-up strategies concluded that an active warm-up combining general aerobic work with task-specific preparation can enhance subsequent performance, largely through raised muscle temperature and post-activation potentiation, while excessive warm-up volume can cause fatigue. Warm-up should prime without draining.

• McGowan CJ, Pyne DB, Thompson KG, Rattray B (2015). Warm-Up Strategies for Sport and Exercise: Mechanisms and Applications View source

A meta-analysis found that protein supplementation augments gains in muscle mass and strength during prolonged resistance training, with benefits plateauing beyond a total intake of roughly 1.6 grams of protein per kilogram of body mass per day. Adequate protein is a support variable for training-induced adaptation.

• Morton RW, Murphy KT, McKellar SR, et al. (2018). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength View source

Observational work found that higher chronic life stress is associated with slower short-term recovery of muscular performance following resistance exercise, so psychological stress can prolong the fatigue produced by training. Recovery capacity is influenced by factors beyond the training session itself.

• Stults-Kolehmainen MA, Bartholomew JB (2012). Psychological stress impairs short-term muscular recovery from resistance exercise View source

Reviews of sleep and muscle indicate that inadequate sleep is associated with impaired recovery, reduced muscle protein synthesis signaling, and blunted strength expression, making sufficient sleep an important support for resistance-training adaptation. Chronic short sleep works against the recovery that training gains depend on.

• Knowles OE, Drinkwater EJ, Urwin CS, Lamon S, Aisbett B (2018). Inadequate sleep and muscle strength: Implications for resistance training View source

A meta-analytical review found that acute sleep loss impairs physical performance, with effects tending to be larger for tasks performed later in the day and for sustained or endurance efforts. Sleep deprivation degrades the ability to express and recover from training.

• Craven J, McCartney D, Desbrow B, et al. (2022). Effects of Acute Sleep Loss on Physical Performance: A Systematic and Meta-Analytical Review View source

An earlier meta-analysis of concurrent training reported that interference is greater when endurance volume and frequency are high and when the endurance mode is running rather than cycling, with hypertrophy and power more affected than pure strength. Managing endurance dose is the main lever for limiting interference.

• Wilson JM, Marin PJ, Rhea MR, Wilson SM, Loenneke JP, Anderson JC (2012). Concurrent training: a meta-analysis examining interference of aerobic and resistance exercises View source

An updated meta-analysis found that adding aerobic training to resistance training does not compromise gains in muscle size and generally does not impair maximal strength, but it can attenuate explosive strength and power, with running tending to interfere more than cycling. The interference effect is modest and mode-dependent.

• Schumann M, Feuerbacher JF, Sunkeler M, et al. (2022). Compatibility of Concurrent Aerobic and Strength Training for Skeletal Muscle Size and Function: An Updated Systematic Review and Meta-Analysis View source

A systematic review found that the one-repetition maximum (1RM) test is a highly reliable measure of maximal strength when the protocol is standardized, showing very high test-retest reliability across both upper- and lower-body exercises and trained and untrained participants. Standardized 1RM assessment is therefore a dependable basis for prescribing and tracking load.

• Grgic J, Lazinica B, Schoenfeld BJ, Pedisic Z (2020). Test-Retest Reliability of the One-Repetition Maximum (1RM) Strength Assessment: a Systematic Review View source

A controlled trial found that stopping sets at a lower velocity-loss threshold (around 20% bar-speed loss) produced strength gains similar to a higher threshold (around 40%) while performing far fewer repetitions and generating less fatigue; the higher velocity-loss condition produced somewhat more hypertrophy but more fatigue. Bar-speed drop is a usable proxy for effort and fatigue.

• Pareja-Blanco F, Rodriguez-Rosell D, Sanchez-Medina L, et al. (2017). Effects of velocity loss during resistance training on athletic performance, strength gains and muscle adaptations View source

A controlled trial inserting a one-week deload at the midpoint of a nine-week supervised resistance-training program found the deload appeared to negatively influence measures of lower-body muscle strength, while leaving lower-body hypertrophy, power and local muscular endurance unaffected. A planned reduction is therefore not free when strength is the outcome being tracked.

• Coleman M, Burke R, Augustin F, et al. (2024). Gaining more from doing less? The effects of a one-week deload period during supervised resistance training on muscular adaptations View source

A cross-sectional survey of 246 competitive strength and physique athletes found that every respondent deloaded within training, integrating a deload into the programme every 5.6 plus or minus 2.3 weeks, with a typical deload lasting 6.4 plus or minus 1.7 days. Deloads were pre-planned to manage energy and fatigue, implemented by reducing volume and load while leaving training frequency and exercise selection unchanged.

• Rogerson D, Nolan D, Korakakis PA, Immonen V, Wolf M, Bell L (2024). Deloading Practices in Strength and Physique Sports: A Cross-sectional Survey View source

A controlled trial found that progressing training by adding repetitions produced hypertrophy and strength gains similar to progressing by adding load, provided sets were taken near failure. Progressive overload can be delivered through either variable without loss of adaptation.

• Plotkin D, Coleman M, Van Every D, et al. (2022). Progressive overload without progressing load? The effects of load or repetition progression on muscular adaptations View source

A meta-analysis found that periodized resistance training produces greater maximal strength gains than non-periodized training, and reviews indicate both undulating and linear models work with no consistent superiority of one over the other. Structured variation of volume and intensity beats holding the same prescription indefinitely.

• Williams TD, Tolusso DV, Fedewa MV, Esco MR (2017). Comparison of Periodized and Non-Periodized Resistance Training on Maximal Strength: A Meta-Analysis View source

A narrative review of time-efficient program design concluded that exercise selection should be built from bilateral, multi-joint exercises taken through full dynamic movements, and that a program needs at least one leg-pressing exercise, one upper-body pulling exercise and one upper-body pushing exercise. Whether those are performed with machines or free weights is a matter of goals, availability and preference rather than of effectiveness.

• Iversen VM, Norum M, Schoenfeld BJ, Fimland MS (2021). No Time to Lift? Designing Time-Efficient Training Programs for Strength and Hypertrophy: A Narrative Review View source

Hypertrophy within a muscle is regionally non-uniform, and which regions grow depends on how the muscle is loaded rather than only on how much. A systematic review of range of motion found that different range configurations preferentially grew different muscles and different sites within a muscle, and a within-subject trial found that changing set structure in a single exercise grew the rectus femoris at some measurement sites and not others.

• Kassiano W, Costa B, Nunes JP, Ribeiro AS, Schoenfeld BJ, Cyrino ES (2023). Which ROMs Lead to Rome? A Systematic Review of the Effects of Range of Motion on Muscle Hypertrophy View source
• Varović D, Žganjer K, Vuk S, Schoenfeld BJ (2021). Drop-Set Training Elicits Differential Increases in Non-Uniform Hypertrophy of the Quadriceps in Leg Extension Exercise View source

Trials on partial range-of-motion training show that partials performed in the lengthened (stretched) position elicit hypertrophy comparable to, and in some measures greater than, full range of motion, whereas partials in the shortened position are inferior. Muscle length at which the exercise is loaded matters more than range per se.

• Pedrosa GF, Lima FV, Schoenfeld BJ, et al. (2022). Partial range of motion training elicits favorable improvements in muscular adaptations when carried out at long muscle lengths View source

A systematic review of range of motion found that full range of motion is at least as effective as partial range for hypertrophy and often superior, and that training which emphasizes the lengthened (stretched) portion of the movement is particularly effective for muscle growth. Partial reps performed at long muscle lengths can rival full-ROM training.

• Kassiano W, Costa B, Nunes JP, Ribeiro AS, Schoenfeld BJ, Cyrino ES (2023). Which ROMs Lead to Rome? A Systematic Review of the Effects of Range of Motion on Muscle Hypertrophy View source

A systematic review of inter-set rest concluded that both short and long rest can build muscle, and that in trained participants measured sensitively the evidence leans toward long rest - the reviewed trials split short from long at 60 seconds. Shorter rest is more time-efficient but can reduce the work completed in later sets.

• Grgic J, Lazinica B, Mikulic P, Krieger JW, Schoenfeld BJ (2017). The effects of short versus long inter-set rest intervals in resistance training on measures of muscle hypertrophy: A systematic review View source

A controlled trial in resistance-trained men found that resting 3 minutes between sets produced greater strength and muscle thickness gains than resting 1 minute, because longer rest preserved the volume-load completed in subsequent sets. Very short rest can compromise the total work performed.

• Schoenfeld BJ, Pope ZK, Benik FM, Hester GM, Sellers J, Nooner JL, Schnaiter JA, Bond-Williams KE, Carter AS, Ross CL, Just BL, Henselmans M, Krieger JW (2016). Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men View source

A large network meta-analysis of resistance-training prescriptions in healthy adults concluded that higher training loads are most effective for maximizing muscular strength, while hypertrophy is driven more by total volume, and that performing multiple weekly sets outperforms single-set training. Load and volume act on strength and size somewhat differently.

• Currier BS, Mcleod JC, Banfield L, et al. (2023). Resistance training prescription for muscle strength and hypertrophy in healthy adults: a systematic review and network meta-analysis View source

A meta-analysis found that low-load and high-load resistance training produce similar muscle hypertrophy when every set is taken to momentary muscular failure, whereas maximal strength gains clearly favour heavier loads. Growth is load-tolerant across the spectrum of loading ranges the trials covered, which split low from high at 60% of one repetition maximum; maximal strength is not.

• Schoenfeld BJ, Grgic J, Ogborn D, Krieger JW (2017). Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-analysis View source

A meta-analysis comparing sets performed to failure versus stopping short found no significant difference in strength or hypertrophy when training volume was equated. Training to failure increased perceived effort and fatigue without clearly superior adaptations.

• Grgic J, Schoenfeld BJ, Orazem J, Sabol F (2022). Effects of resistance training performed to repetition failure or non-failure on muscular strength and hypertrophy: A systematic review and meta-analysis View source

A meta-analysis found only a trivial advantage for training to set failure over stopping short of it for hypertrophy, with no moderating effect of volume load or relative load, and no advantage at all when the comparison was restricted to momentary muscular failure. Higher velocity-loss thresholds, which are theoretically closer to failure, did not reliably produce more growth either.

• Refalo MC, Helms ER, Trexler ET, Hamilton DL, Fyfe JJ (2023). Influence of Resistance Training Proximity-to-Failure on Skeletal Muscle Hypertrophy: A Systematic Review with Meta-Analysis View source

A meta-analysis on strength found that once weekly training volume is equated, resistance-training frequency has no meaningful independent effect on maximal strength gains. Distributing the same volume over more sessions did not by itself increase strength.

• Grgic J, Schoenfeld BJ, Davies TB, Lazinica B, Krieger JW, Pedisic Z (2018). Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis View source

A meta-analysis of frequency studies found that training a muscle group twice per week produced greater hypertrophy than once per week. When total weekly volume is equated, however, the added benefit of frequency largely reflects the ability to accumulate more quality volume rather than frequency itself.

• Schoenfeld BJ, Ogborn D, Krieger JW (2016). Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis View source

A meta-regression of the resistance-training dose literature found a graded dose-response between weekly set volume and both hypertrophy and strength: the posterior probability that gains increase with volume was 100% for each. Both best-fit models show diminishing returns, considerably more pronounced for strength than for size, and neither identifies a point past which volume stops helping. The dose is also a per-muscle accounting construct rather than a count of hard sets of one lift - sets are classified direct or indirect, and an indirect set is credited 0.5 of a set under the fractional method the authors found best supported.

• 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 View source

A systematic review comparing moderate and high hypertrophy volumes classified under 12 weekly sets per muscle as low, 12-20 as moderate and over 20 as high, and found no difference between moderate and high volumes for the quadriceps or the biceps brachii, with an advantage for high volume only in the triceps brachii. It concluded that 12-20 weekly sets per muscle group is the standard recommendation for trained lifters.

• Baz-Valle E, Balsalobre-Fernandez C, Alix-Fages C, Santos-Concejero J (2022). A Systematic Review of The Effects of Different Resistance Training Volumes on Muscle Hypertrophy View source

A meta-regression of 15 studies found a graded dose-response between weekly resistance-training volume and hypertrophy: each additional weekly set per muscle was associated with roughly a 0.37% greater gain in muscle size, and higher weekly set categories produced meaningfully larger gains than lower ones. The relationship is positive but shows diminishing returns rather than being unlimited.

• 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 View source