The role of supervision in resistance training
An exploratory systematic review and meta-analysis
Keywords:Supervision, strength, muscle, training
Background: The body of resistance training literature appears heavily focused upon investigating efficacy of interventions by dint of most incorporating supervision (SUP). Authors have suggested that a lack of SUP within strength training results in inadequate workout quality and diminished results yet, since many people choose to perform resistance training unsupervised (UNSUP), it seems important to understand effectiveness of resistance training under such ecologically valid conditions. That is, the extent to which SUP might impact adaptation. Objective: To collectively explore the effects of SUP upon performance/function and body composition outcomes. Design: Exploratory systematic review and meta-analysis. Search and Inclusion: A systematic literature search using a Boolean search strategy was conducted with PubMed/MEDLINE, Scopus, and CINAHL in December 2020 and was supplemented with additional ‘snowballing’ searches. To be included in our analysis, studies had to be experimental trials including at least one performance/functional measure (e.g., strength, speed, power, function, endurance, and cardiorespiratory fitness) and/or body composition measure (body fat percentage, fat mass, and fat free mass). After search and screening, 12 studies were eligible for inclusion including 301 participants in SUP groups and a further 276 participants in UNSUP groups. Results: The cluster robust main model for all performance/function effects (57 across 12 clusters [median = 4, range = 1-12 effects per cluster]) revealed a small, standardised point estimate favouring SUP, though with relatively poor precision for the interval estimate that ranged from a trivial to a moderate effect favouring SUP (0.28 [95%CI = 0.02 to 0.55]). For sub-grouped outcome types there was very poor precision of robust estimates for speed, power, function, and endurance, with all ranging from large effects supporting UNSUP to large effects supporting SUP. However, for strength there was a small, standardised point estimate favouring SUP though with moderate precision for the interval estimate that ranged from a trivial effect favouring SUP to a moderate effect favouring SUP (0.40 [95%CI = 0.06 to 0.74]). The cluster robust main model for all body composition effects (18 across 6 clusters [median = 3, range = 1-6 effects per cluster]) revealed a trivial standardised point estimate favouring SUP that was relatively precise in the interval estimate ranging only trivial effects in either direction (0.07 [95%CI = -0.01 to 0.15]). Conclusions: The results of the present systematic review and exploratory meta-analysis suggest that, broadly speaking, SUP resistance training might produce a small effect on increases in performance/function, most likely in strength, compared to UNSUP, and has little to no impact on body composition outcomes. However, the lack of role and purpose within supervision as well as the lack of parity in UNSUP exercise interventions make providing a conclusive and overarching recommendation difficult.
Schoenfeld BJ, Grgic J, Ogborn D, Krieger JW. Strength and hypertrophy adaptations be-tween low-vs. high-load resistance training: a systematic review and meta-analysis. J Strength Cond Res. 2017;31:3508–3523.
Schoenfeld BJ, Ogborn DI, Krieger JW. Effect of repetition duration during resistance training on muscle hypertrophy: a systematic review and meta-analysis. Sports Med. 2015;45:577–585.
Schoenfeld BJ, Ogborn D, Krieger JW. Dose-response relationship between weekly resistance training volume and increases in muscle mass: A systematic review and meta-analysis. J Sports Sci. 2017;35:1073–1082.
Schoenfeld BJ, Grgic J, Krieger J. 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. J Sports Sci. 2019;37:1286–1295.
Nunes JP, Grgic J, Cunha PM, Ribeiro AS, Schoenfeld BS, de Salles BF, Cyrino ES. What influ-ence does resistance exercise order have on muscular strength gains and muscle hypertro-phy? A systematic review and meta-analysis. Eur J Sport Sci. 2021;21(2):149-157.
Schoenfeld BJ, Grgic J. Effects of range of motion on muscle development during resistance training interventions: A systematic review. SAGE Open Med. 2020;8: 2050312120901559.
Davies T, Orr R, Halaki M, Hackett D. Effect of training leading to repetition failure on muscu-lar strength: a systematic review and meta-analysis. Sports Med. 2016. 1;46(4):487-502.
Schoenfeld BJ, Grgic J. Does training to failure maximize muscle hypertrophy? Strength Cond J. 2019;41:108–113.
Grgic J, Schoenfeld BJ, Orazem J, Sabol F. Effects of resistance training performed to repeti-tion failure or non-failure on muscular strength and hypertrophy: a systematic review and meta-analysis. J Sport Health Sci. 23;S2095-2546(21)00007-7.
Halperin I, Malleron T, Har-Nir I, Androulakis-Korakakis P, Wolf M, Fisher J, Steele J. Accuracy in predicting repetitions to task failure in resistance exercise: a scoping review and explorato-ry meta-analysis. Sports Med. 2021; Online ahead of print
Ratamess NA, Faigenbaum AD, Hoffman JR, Kang J. Self-selected resistance training intensity in healthy women: the influence of a personal trainer. J Strength Cond Res. 2008;22(1):103–111.
Dias MRC, Simão RF, Saavedra FJ, Ratamess NA. Influence of a personal trainer on self-selected loading during resistance exercise. J Strength Cond Res. 2017;31(7):1925–1930.
Kraemer WJ, Ratamess NA, French DN. Resistance training for health and performance. Curr Sports Med Rep. 2002;1(3):165–171.
Coutts AJ, Murphy AJ, Dascombe BJ. Effect of direct supervision of a strength coach on measures of muscular strength and power in young rugby league players. J Strength Cond Res. 2004;18(2):316-323.
Hillmann A, Pearson DR. Supervision: The key to strength training success. Strength Cond J. 1995;17(5):67–71.
Bull FC, Al-Ansari SS, Biddle S, Borodulin K, Buman MP, Cardon G, Carty C, Chaput JP, Chastin S, Chou R, Dempsey PC. World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br J Sports Med. 2020;54(24):1451-62.
Beedie C, Mann S, Jimenez A, Kennedy L, Lane AM, Domone S, Wilson S, Whyte G. Death by effectiveness: exercise as medicine caught in the efficacy trap! British Journal of Sports Med. 2016;50(6):323.
Steele J, Fisher J, Skivington M, Dunn C, Arnold J, Tew G, Batterham AM, Nunan D, O’Driscoll JM, Mann S, Beedie C. A higher effort-based paradigm in physical activity and exercise for public health: making the case for a greater emphasis on resistance training. BMC Public Health. 2017;17(1):1-8.
Mazzetti SA, Kraemer WJ, Volek JS, Duncan ND, Ratamess NA, Gomez AL, Newton RU, Hakkinen KE, Fleck SJ. The influence of direct supervision of resistance training on strength performance. Med Sci Sports Exerc. 2000;32(6):1175-84.
Bloomquist K, Langberg H, Karlsen S, Madsgaard S, Boesen M, Raastad T. Effect of range of motion in heavy load squatting on muscle and tendon adaptations. Eur J Appl Physiol. 2013;113(8):2133-42.
Faigenbaum AD, Myer GD. Resistance training among young athletes: safety, efficacy and in-jury prevention effects. Br J Sports Med. 2010;44(1):56–63.
Stricker PR, Faigenbaum AD, McCambridge TM. Resistance training for children and adoles-cents. Pediatrics. 2020;145(6).
Travis TN, Brown V, Caulfield S, Doscher M, McHenry P, Statler T. NSCA Strength and condi-tioning professional standards and guidelines. Strength Cond J. 2017;39:1-24.
Steele J, Raubold K, Kemmler W, Fisher J, Gentil P, Giessing J. The effects of 6 months of pro-gressive high effort resistance training methods upon strength, body composition, function, and wellbeing of elderly adults. BioMed Research International. 2017.
Gentil P, Bottaro M. Influence of supervision ratio on muscle adaptations to resistance train-ing in nontrained subjects. J Strength Cond Res. 2010;24(3):639–643.
Köppel M, Mathis K, Schmitz KH, Wiskemann J. Muscle Hypertrophy in Cancer Patients and Survivors via Strength Training. A Meta-Analysis and Meta-Regression. Crit Rev Oncol Hema-tol. 2021;103371.
Lacroix A, Hortobagyi T, Beurskens R, Granacher U. Effects of supervised vs. unsupervised training programs on balance and muscle strength in older adults: a systematic review and meta-analysis. Sports Med. 2017;47(11):2341-61.
Steele J, Androulakis-Korakakis P, Carlson L, Williams D, Phillips S, Smith D, Schoenfeld BJ, Loenneke JP, Winett R, Abe T, Dufour S, et al. The Impact of Coronavirus (COVID-19) Related Public-Health Measures on Training Behaviours of Individuals Previously Participating in Re-sistance Training: A Cross-Sectional Survey Study. Sports Med. 2021;51(7):1561-80.
Moher D, Liberati A, Tetzlaff J, Altman DG, Prisma Group. Preferred reporting items for sys-tematic reviews and meta-analyses: the PRISMA statement. PLoS medicine. 2009;6(7):e1000097.
Dalager T, Bredahl TG, Pedersen MT, Boyle E, Andersen LL, Sjøgaard G. Does training fre-quency and supervision affect compliance, performance and muscular health? A cluster ran-domized controlled trial. Man Ther. 2015;20(5):657-65.
Rustaden AM, Haakstad LA, Paulsen G, Bø K. Effects of BodyPump and resistance training with and without a personal trainer on muscle strength and body composition in overweight and obese women—A randomised controlled trial. Obes Res Clin Pract. 2017;11(6):728-39.
Moseley AM, Herbert RD, Sherrington C, Maher CG. Evidence for physiotherapy practice: a survey of the Physiotherapy Evidence Database (PEDro). Aust J Physiother. 2002;48(1):43-9.
Elkins MR, Herbert RD, Moseley AM, Sherrington C, Maher C. Rating the quality of trials in systematic reviews of physical therapy interventions. Cardiopulm Phys Ther J. 2010;21(3):20.
Kümmel J, Kramer A, Giboin LS, Gruber M. Specificity of balance training in healthy individu-als: a systematic review and meta-analysis. Sports Med. 2016;46(9):1261-71.
Viechtbauer W. Conducting meta-analyses in R with the metafor package. J Stat Soft. 2010;36(3):1-48.
Morris SB. Estimating effect sizes from pretest-posttest-control group designs. Organ Res Methods. 2008;11(2):364-86.
Cohen J. Statistical power analysis for the behavioral sciences. Academic press; 2013.
Hedges LV, Tipton E, Johnson MC. Robust variance estimation in meta‐regression with de-pendent effect size estimates. Res Synth Methods. 2010;1(1):39-65.
Amrhein V, Greenland S, McShane B. Scientists rise up against statistical significance. Nature. 2019(7748):305-7.
McShane BB, Gal D, Gelman A, Robert C, Tackett JL. Abandon statistical significance. The Am Stat. 2019;73(sup1):235-45.
Higgins JP, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ. 2003;327(7414):557-60.
Higgins JP, Altman DG, Gøtzsche PC, Jüni P, Moher D, Oxman AD, Savović J, Schulz KF, Weeks L, Sterne JA. The Cochrane Collaboration's tool for assessing risk of bias in randomised trials. BMJ. 2011 29;343(7829).
Atkinson G, Williamson P, Batterham AM. Issues in the determination of ‘responders’ and ‘non‐responders’ in physiological research. Exp Physiol. 2019;104(8):1215-25.
Nakagawa S, Poulin R, Mengersen K, Reinhold K, Engqvist L, Lagisz M, Senior AM. Meta‐analysis of variation: ecological and evolutionary applications and beyond. Methods Ecol Evol. 2015;6(2):143-52.
Stefanov T, Vekova A, Bonova I, Tzvetkov S, Kurktschiev D, Blüher M, Temelkova-Kurktschiev T. Effects of supervised vs non-supervised combined aerobic and resistance exercise pro-gramme on cardiometabolic risk factors. Cent Eur J Public Health. 2013;21(1):8-16.
Hunter JR, Gordon BA, Lythgo N, Bird SR, Benson AC. Exercise at an onsite facility with or without direct exercise supervision improves health‐related physical fitness and exercise par-ticipation: An 8‐week randomised controlled trial with 15‐month follow‐up. Health Prom J Aust. 2018;29(1):84-92.
Çergel Y, Topuz O, Alkan H, Sarsan A, Akkoyunlu NS. The effects of short-term back extensor strength training in postmenopausal osteoporotic women with vertebral fractures: compari-son of supervised and home exercise program. Arch Osteoporos. 2019;14(1): 1–8.
Orange ST, Marshall P, Madden LA, Vince RV. Short-term training and detraining effects of supervised vs. unsupervised resistance exercise in aging adults. J Strength Cond Res. 2019;33(10):2733–2742.
Hunter JR, Gordon BA, Bird SR, Benson AC. Exercise supervision is important for cardiometa-bolic health improvements: a 16-week randomized controlled trial. J Strength Cond Res. 2020;34(3): 866–877.
Kullman EL, Saylor SM, Little KD. Efficacy of whole-body suspension training on enhancing functional movement abilities following a supervised or home-based training program. J Sports Med Phys Fit. 2019;60(2):244–250.
Storer TW, Dolezal BA, Berenc MN, Timmins JE, Cooper CB. Effect of supervised, periodized exercise training vs. self-directed training on lean body mass and other fitness variables in health club members. J Strength Cond Res. 2014;28(7):1995-2006.
Enoksen E, Staxrud M, Tønnessen E, Shalfawi SA. The effect of supervised strength training on young elite male soccer players’ physical performance. Serb J Sports Sci. 2013;7(4).
Grotle M, Vøllestad NK, Veierød MB, Brox JI. Fear-avoidance beliefs and distress in relation to disability in acute and chronic low back pain. Pain. 2004;112(3):343–352.
Khodadad B, Letafatkar A, Hadadnezhad M, Shojaedin S. Comparing the effectiveness of cognitive functional treatment and lumbar stabilization treatment on pain and movement control in patients with low back pain. Sports Health. 2020;12(3):289–295.
Schmidt RA. Motor schema theory after 27 years: Reflections and implications for a new the-ory. Res Quart Exerc Sport. 2003;74(4):366–375.
Brown LE, Weir JP. ASEP procedures recommendation I: accurate assessment of muscular strength and power. JEP Online. 2001;4(3).
Fisher J, Steele J, Smith D. High-and low-load resistance training: interpretation and practical application of current research findings. Sports Med. 2017;47(3):393–400.
Baker D. Science and practice of coaching a strength training program for novice and inter-mediate-level athletes. Strength Cond J. 2001;23(2):61.
Kerr ZY, Collins CL, Dawn Comstock R. Epidemiology of weight training-related injuries pre-senting to United States emergency departments, 1990 to 2007. Am J Sports Med. 2010;38(4):765–771.
Steele J, Fisher J, Giessing J, Gentil P. Clarity in reporting terminology and definitions of set endpoints in resistance training. Muscle Nerve. 2017;56(3):368–374.
Garber CE, Blissmer B, Deschenes MR, Franklin BA, Lamonte MJ, Lee IM, Nieman DC, Swain DP. American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Med Sci Sports Exerc. 2011;43(7):1334-59.
Denton F, Power S, Waddell A, Birkett S, Duncan M, Harwood A, McGregor G, Rowley N, Broom D. Is It Really Home-Based? A Commentary on the Necessity for Accurate Definitions across Exercise and Physical Activity Programmes. Int J Environ Res Public Health. 2021;18(17):9244.
Teyhen DS, Shaffer SW, Lorenson CL, Halfpap JP, Donofry DF, Walker MJ, Dugan JL, Childs JD. The functional movement screen: a reliability study. J Orthop Sports Phys Ther. 2012;42(6):530-40.
Massey CD, Maneval MW, Phillips J, Vincent J, White G, Zoeller B. An analysis of teaching and coaching behaviors of elite strength and conditioning coaches. J Strength Cond Res. 2002;16(3):456-60.
Hong J, Kim J, Kim SW, Hong HJ. Effects of home-based tele-exercise on sarcopenia among community-dwelling elderly adults: Body composition and functional fitness. Exp Gerontol. 2017;87:33–39.
Copyright (c) 2021 James P. Fisher, James Steele, Milo Wolf, Patroklos Androulakis-Korakakis, Dave Smith, Jürgen Giessing
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