Eric R. Helms

A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults

Objective We performed a systematic review, meta-analysis and meta-regression to determine if dietary protein supplementation augments resistance exercise training (RET)-induced gains in muscle mass and strength. Data sources A systematic search of Medline, Embase, CINAHL and SportDiscus. Eligibility criteria Only randomised controlled trials with RET ≥6 weeks in duration and dietary protein supplementation. Design Random-effects meta-analyses and meta-regressions with four a priori determined covariates. Two-phase break point analysis was used to determine the relationship between total protein intake and changes in fat-free mass (FFM). Results Data from 49 studies with 1863 participants showed that dietary protein supplementation significantly (all p<0.05) increased changes (means (95% CI)) in: strength—one-repetition-maximum (2.49 kg (0.64, 4.33)), FFM (0.30 kg (0.09, 0.52)) and muscle size—muscle fibre cross-sectional area (CSA; 310 µm2 (51, 570)) and mid-femur CSA (7.2 mm2 (0.20, 14.30)) during periods of prolonged RET. The impact of protein supplementation on gains in FFM was reduced with increasing age (−0.01 kg (−0.02,–0.00), p=0.002) and was more effective in resistance-trained individuals (0.75 kg (0.09, 1.40), p=0.03). Protein supplementation beyond total protein intakes of 1.62 g/kg/day resulted in no further RET-induced gains in FFM. Summary/conclusion Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults. Increasing age reduces and training experience increases the efficacy of protein supplementation during RET. With protein supplementation, protein intakes at amounts greater than ~1.6 g/kg/day do not further contribute RET-induced gains in FFM.

A Systematic Review of Dietary Protein during Caloric Restriction in Resistance Trained Lean Athletes: A Case for Higher Intakes

UNLABELLED Caloric restriction occurs when athletes attempt to reduce body fat or make weight. There is evidence that protein needs increase when athletes restrict calories or have low body fat. PURPOSE The aims of this review were to evaluate the effects of dietary protein on body composition in energy-restricted resistance-trained athletes and to provide protein recommendations for these athletes. METHODS Database searches were performed from earliest record to July 2013 using the terms protein, and intake, or diet, and weight, or train, or restrict, or energy, or strength, and athlete. Studies (N = 6) needed to use adult (≥ 18 yrs), energy-restricted, resistance-trained (> 6 months) humans of lower body fat (males ≤ 23% and females ≤ 35%) performing resistance training. Protein intake, fat free mass (FFM) and body fat had to be reported. RESULTS Body fat percentage decreased (0.5-6.6%) in all study groups (N = 13) and FFM decreased (0.3-2.7kg) in nine of 13. Six groups gained, did not lose, or lost nonsignificant amounts of FFM. Five out of these six groups were among the highest in body fat, lowest in caloric restriction, or underwent novel resistance training stimuli. However, the one group that was not high in body fat that underwent substantial caloric restriction, without novel training stimuli, consumed the highest protein intake out of all the groups in this review (2.5-2.6g/kg). CONCLUSIONS Protein needs for energy-restricted resistance-trained athletes are likely 2.3-3.1g/kg of FFM scaled upwards with severity of caloric restriction and leanness.

Novel Resistance Training-Specific Rating of Perceived Exertion Scale Measuring Repetitions in Reserve.

Abstract Zourdos, MC, Klemp, A, Dolan, C, Quiles, JM, Schau, KA, Jo, E, Helms, E, Esgro, B, Duncan, S, Garcia Merino, S, and Blanco, R. Novel resistance training–specific rating of perceived exertion scale measuring repetitions in reserve. J Strength Cond Res 30(1): 267–275, 2016—The primary aim of this study was to compare rating of perceived exertion (RPE) values measuring repetitions in reserve (RIR) at particular intensities of 1 repetition maximum (RM) in experienced (ES) and novice squatters (NS). Furthermore, this investigation compared average velocity between ES and NS at the same intensities. Twenty-nine individuals (24.0 ± 3.4 years) performed a 1RM squat followed by a single repetition with loads corresponding to 60, 75, and 90% of 1RM and an 8-repetition set at 70% 1RM. Average velocity was recorded at 60, 75, and 90% 1RM and on the first and last repetitions of the 8-repetition set. Subjects reported an RPE value that corresponded to an RIR value (RPE-10 = 0-RIR, RPE-9 = 1-RIR, and so forth). Subjects were assigned to one of the 2 groups: (a) ES (n = 15, training age: 5.2 ± 3.5 years) and (b) NS (n = 14, training age: 0.4 ± 0.6 years). The mean of the average velocities for ES was slower (p ⩽ 0.05) than NS at 100% and 90% 1RM. However, there were no differences (p > 0.05) between groups at 60, 75%, or for the first and eighth repetitions at 70% 1RM. In addition, ES recorded greater RPE at 1RM than NS (p = 0.023). In ES, there was a strong inverse relationship between average velocity and RPE at all percentages (r = −0.88, p < 0.001), and a strong inverse correlation in NS between average velocity and RPE at all intensities (r = −0.77, p = 0.001). Our findings demonstrate an inverse relationship between average velocity and RPE/RIR. Experienced squatter group exhibited slower average velocity and higher RPE at 1RM than NS, signaling greater efficiency at high intensities. The RIR-based RPE scale is a practical method to regulate daily training load and provide feedback during a 1RM test.

Application of the Repetitions in Reserve-Based Rating of Perceived Exertion Scale for Resistance Training

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RPE and Velocity Relationships for the Back Squat, Bench Press, and Deadlift in Powerlifters.

Abstract Helms, ER, Storey, A, Cross, MR, Browm, SR, Lenetsky, S, Ramsay, H, Dillen, C, and Zourdos, MC. RPE and velocity relationships for the back squat, bench press, and deadlift in powerlifters. J Strength Cond Res 31(2): 292–297, 2017—The purpose of this study was to compare average concentric velocity (ACV) and rating of perceived exertion (RPE) based on repetitions in reserve on the squat, bench press, and deadlift. Fifteen powerlifters (3 women and 12 men, mean age 28.4 ± 8.5 years) worked up to a one repetition maximum (1RM) on each lift. Rating of perceived exertion was recorded on all sets, and the ACV was recorded for all sets performed at 80% of estimated 1RM and higher, up to 1RM. Rating of perceived exertion at 1RM on squat, bench press, and deadlift was 9.6 ± 0.5, 9.7 ± 0.4, and 9.6 ± 0.5, respectively and was not significantly different (p > 0.05). The ACV at 1RM on squat, bench press and deadlift was 0.23 ± 0.05, 0.10 ± 0.04, and 0.14 ± 0.05 m·second−1, respectively. Squat was faster than both bench press and deadlift (p > 0.001), and deadlift was faster than bench press (p = 0.05). Very strong relationships (r = 0.88–0.91) between percentage 1RM and RPE were observed on each lift. The ACV showed strong (r = −0.79 to −0.87) and very strong (r = −0.90 to 92) inverse relationships with RPE and percentage 1RM on each lift, respectively. We conclude that RPE may be a useful tool for prescribing intensity for squat, bench press, and deadlift in powerlifters, in addition to traditional methods such as percentage of 1RM. Despite high correlations between percentage 1RM and ACV, a “velocity load profile” should be developed to prescribe intensity on an individual basis with appropriate accuracy.

A Scientific Rationale to Improve Resistance Training Prescription in Exercise Oncology

To date, the prevailing evidence in the field of exercise oncology supports the safety and efficacy of resistance training to attenuate many oncology treatment-related adverse effects, such as risk for cardiovascular disease, increased fatigue, and diminished physical functioning and quality of life. Moreover, findings in the extant literature supporting the benefits of exercise for survivors of and patients with cancer have resulted in the release of exercise guidelines from several international agencies. However, despite research progression and international recognition, current exercise oncology-based exercise prescriptions remain relatively basic and underdeveloped, particularly in regards to resistance training. Recent publications have called for a more precise manipulation of training variables such as volume, intensity, and frequency (i.e., periodization), given the large heterogeneity of a cancer population, to truly optimize clinically relevant patient-reported outcomes. Indeed, increased attention to integrating fundamental principles of exercise physiology into the exercise prescription process could optimize the safety and efficacy of resistance training during cancer care. The purpose of this article is to give an overview of the current state of resistance training prescription and discuss novel methods that can contribute to improving approaches to exercise prescription. We hope this article may facilitate further evaluation of best practice regarding resistance training prescription, monitoring, and modification to ultimately optimize the efficacy of integrating resistance training as a supportive care intervention for survivors or and patients with cancer.

Rating of Perceived Exertion as a Method of Volume Autoregulation Within a Periodized Program

Abstract Helms, ER, Cross, MR, Brown, SR, Storey, A, Cronin, J, and Zourdos, MC. Rating of perceived exertion as a method of volume autoregulation within a periodized program. J Strength Cond Res 32(6): 1627–1636, 2018—The purpose of this investigation was to observe how a rating of perceived exertion (RPE)-based autoregulation strategy impacted volume performed by powerlifters. Twelve (26 ± 7 years, n = 9 men, n = 3 women) nationally qualified powerlifters performed the back squat, bench press, and deadlift 3x per week on nonconsecutive days in a session order of hypertrophy, power, and then strength; for 3 weeks. Each session subjects performed an initial top set for a prescribed number of repetitions at a target RPE. A second top set was performed if the RPE score was too low, then subsequent back-off sets at a reduced load were performed for the same number of repetitions. When the prescribed RPE was reached or exceeded, sets stopped; known as an “RPE stop.” The percentage load reduction for back-off sets changed weekly: there were 2, 4, or 6% RPE stop reductions from the top set. The order in which RPE stop weeks were performed was counterbalanced among subjects. Weekly combined relative volume load (squat + bench press + deadlift), expressed as sets x repetitions x percentage 1-repetition maximum was different between weeks (p < 0.001): 2% = 74.6 ± 22.3; 4% = 88.4 ± 23.8; 6% = 114.4 ± 33.4. Combined weekly bench press volume (hypertrophy + power + strength) was significantly higher in accordance with load reduction magnitude (2% > 4% > 6%; p ⩽ 0.05), combined squat volume was greater in 6 vs. 2% (p ⩽ 0.05), and combined deadlift volume was greater in 6 vs. 2% and 4% (p ⩽ 0.05). Therefore, it does seem that volume can be effectively autoregulated using RPE stops as a method to dictate number of sets performed.

Changes in Body Composition and Performance With Supplemental Hmb‐fa+atp

Request for Clarification:The authors are satisfied that their original responses to the prior Manuscript Clarification address the issues raised here.Lowery et al. (6) reported, in contrast to an often‐observed heterogeneity in training‐induced hypertrophy, remarkably consistent between‐group chang

The Potential for a Targeted Strength-Training Program to Decrease Asymmetry and Increase Performance: A Proof of Concept in Sprinting

The global application of horizontal force (FH) via hip extension is related to improvements in sprint performance (eg, maximal velocity [vmax] and power [Pmax]). Little is known regarding the contribution of individual leg FH and how a difference between the legs (asymmetry) might subsequently affect sprint performance. The authors assessed a single male athlete for pre-post outcomes of a targeted hip-extension training program on FH asymmetry and sprint-performance metrics. An instrumented nonmotorized treadmill was used to obtain individual leg and global sprint kinetics and determine the athletes strong and weak leg, with regard to the ability to produce FH while sprinting. Following a 6-wk control block of testing, a 6-wk targeted training program was added to the athletes strength-training regimen, which aimed to strengthen the weak leg and improve hip-extension function during sprinting. Preintervention to postintervention, the athlete increased FH (standardized effect [ES] = 2.2; +26%) in his weak leg, decreased the FH asymmetry (ES = -0.64; -19%), and increased vmax (ES = 0.67; +2%) and Pmax (ES = 3.2; +15%). This case study highlighted a promising link between a targeted training intervention to decrease asymmetry in FH and subsequent improvement of sprint-performance metrics. These findings also strengthen the theoretical relationship between the contribution of individual leg FH and global FH while sprinting, indicating that reducing asymmetry may decrease injury risk and increase practical performance measures. This case study may stimulate further research investigating targeted training interventions in the field of strength and conditioning and injury prevention.

RPE vs Percentage 1RM Loading in Periodized Programs Matched for Sets and Repetitions

Purpose: To investigate differences between rating of perceived exertion (RPE) and percentage one-repetition maximum (1RM) load assignment in resistance-trained males (19–35 years) performing protocols with matched sets and repetitions differentiated by load-assignment. Methods: Participants performed squats then bench press 3x/weeks in a daily undulating format over 8-weeks. Participants were counterbalanced by pre-test 1RM then assigned to percentage 1RM (1RMG, n = 11); load-assignment via percentage 1RMs, or RPE groups (RPEG, n = 10); participant-selected loads to reach target RPE ranges. Ultrasonography determined pre and post-test pectoralis (PMT), and vastus lateralis muscle thickness at 50 (VLMT50) and 70% (VLMT70) femur-length. Results: Bench press (1RMG +9.64 ± 5.36; RPEG + 10.70 ± 3.30 kg), squat (1RMG + 13.91 ± 5.89; RPEG + 17.05 ± 5.44 kg) and their combined-total 1RMs (1RMG + 23.55 ± 10.38; RPEG + 27.75 ± 7.94 kg) increased (p < 0.05) in both groups as did PMT (1RMG + 1.59 ± 1.33; RPEG +1.90 ± 1.91 mm), VLMT50 (1RMG +2.13 ± 1.95; RPEG + 1.85 ± 1.97 mm) and VLMT70 (1RMG + 2.40 ± 2.22; RPEG + 2.31 ± 2.27 mm). Between-group differences were non-significant (p > 0.05). Magnitude-based inferences revealed 79, 57, and 72% chances of mean small effect size (ES) advantages for squat; ES 90% confidence limits (CL) = 0.50 ± 0.63, bench press; ES 90% CL = 0.28 ± 0.73, and combined-total; ES 90% CL = 0.48 ± 0.68 respectively, in RPEG. There were 4, 14, and 6% chances 1RMG had a strength advantage of the same magnitude, and 18, 29, and 22% chances, respectively of trivial differences between groups. Conclusions: Both loading-types are effective. However, RPE-based loading may provide a small 1RM strength advantage in a majority of individuals.