-repetition maximum (1RM). Even though 1RMs are valid, reliable, and require no monitoring equipment, they are time consuming when conducted with large groups. Moreover, maximal strength can fluctuate daily when an individual is fatigued or significantly increase within a few weeks due to training adaptation
Harry G. Banyard, James J. Tufano, Jose Delgado, Steve W. Thompson, and Kazunori Nosaka
George J. Salem, Man-Ying Wang, and Susan Sigward
In order to obtain joint-specific baseline strength characteristics in older adults, clinicians and researchers must have knowledge regarding the relative stability of the various strength tests (the strength difference between repeated measures) and the number of prebaseline practice sessions required to obtain consistent data. To address these needs, the relative multiple-test stability and reliability associated with lower extremity isokinetic and 1-repetition-maximum (1RM) strength measures were assessed in a sample of older adults (N = 30, 65.2 ± 6.3 years), over 4 weeks (T1-T4). Isokinetic ankle plantar-flexion (30°/s) strength and 1RM ankle plantar-flexion, leg-press, and knee-flexion strength exhibited poor stability between Weeks T1 and T2 but stabilized between Weeks T2 and T3 and Weeks T3 and T4. The measures exhibited low incidence of injury and induced low levels of residual muscle soreness. Findings suggest that the 1RM measures require at least 1 prebaseline training session in order to establish consistent baseline performance and are more reliable than isokinetic ankle plantar-flexion tests.
Sijie Tan, Jianxiong Wang, and Shanshan Liu
The purpose of this study was to establish the one-repetition maximum (1RM) prediction equations of a biceps curl, bench press, and squat from the submaximal skeletal muscle strength of 4–10RM or 11–15RM in older adults. The first group of 109 participants aged 60–75 years was recruited to measure their 1RM, 4–10RM, and 11–15RM of the three exercises. The 1RM prediction equations were developed by multiple regression analyses. A second group of participants with similar physical characteristics to the first group was used to evaluate the equations. The actual measured 1RM of the second group correlated significantly to the predicted 1RM obtained from the equations (r values were from .633–.985), and standard error of estimate ranged from 1.08–5.88. Therefore, the equations can be used to predict 1RM from submaximal skeletal muscle strength accurately for older adults.
Vasilios I. Kalapotharakos, Maria Michalopoulou, George Godolias, Savvas P. Tokmakidis, Paraskevi V. Malliou, and Vasilios Gourgoulis
The purpose of this study was to investigate the effects of a 12-week resistance-training program on muscle strength and mass in older adults. Thirty-three inactive participants (60–74 years old) were assigned to 1 of 3 groups: high-resistance training (HT), moderate-resistance training (MT), and control. After the training period, both HT and MT significantly increased 1-RM body strength, the peak torque of knee extensors and flexors, and the midthigh cross-sectional area of the total muscle. In addition, both HT and MT significantly decreased the abdominal circumference. HT was more effective in increasing 1-RM strength, muscle mass, and peak knee-flexor torque than was MT. These data suggest that muscle strength and mass can be improved in the elderly with both high- and moderate-intensity resistance training, but high-resistance training can lead to greater strength gains and hypertrophy than can moderate-resistance training.
Jerry L. Mayhew, Sidney Palmer Hill, Melissa D. Thompson, Erin C. Johnson, and Lyndsay Wheeler
The purpose of this study was to evaluate the effectiveness of repetitions to fatigue (RTF) using absolute and relative muscle-endurance performances to estimate 1-repetition-maximum (1-RM) bench-press performance in high school male athletes.
Members of high school athletic teams (n = 118, age = 16.5 ± 1.1 y, weight = 82.7 ± 18.7 kg) were tested for 1-RM bench press and RTF with an absolute load of 61.4 kg and a relative load that produced 7 to 10 RTF (7- to 10-RM). All participants had completed a minimum of 4 wk of resistance training before measurement.
All 7- to 10-RM-prediction equations had higher correlations between predicted and actual 1-RM (r > .98) than the 61.4-kg absolute-load equation (r = .95). Despite the high correlations, only 3 of 11 equations produced predicted values that were nonsignificantly different from actual 1-RM. The best 7- to 10-RM equation predicted 65% of the athletes’ performances within ±4.5 kg of their actual 1-RM. The addition of simple anthropometric dimensions did not increase the validity correlations or decrease the prediction errors.
The 7- to 10-RM method can provide an accurate method of estimating strength levels for adjusting loads in a training program and is more accurate for predicting 1-RM bench press in high school athletes than the 61.4-kg repetition method.
Arny A. Ferrando and Nancy R. Green
The effect of boron supplementation was investigated in 19 male bodybuilders, ages 20–27 years. Ten were given a 2.5-mg boron supplement while 9 were given a placebo every day for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on Days 1 and 49 of the study. Plasma boron values were significantly (p<0.05) different as the experimental group increased from (±SD) 20.1 ±7.7 ppb pretest to 32.6 ±27.6 ppb posttest, while the control group mean decreased from 15.1 ±14.4 ppb pretest to 6.3 ±5.5 ppb posttest. Analysis of variance indicated no significant effect of boron supplementation on any of the dependent variables. Both groups demonstrated significant increases in total testosterone, lean body mass, 1-RM squat, and 1-RM bench press. The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser trained bodybuilders, and that boron supplementation had no effect on these measures.
Danica Janicijevic, Ivan Jukic, Jonathon Weakley, and Amador García-Ramos
Resistance training can enable neuromuscular adaptations that can improve health and athletic performance. 1 , 2 During resistance training, the 1-repetition maximum (1RM) load (ie, the maximum load that can be lifted only once with proper technique) in a given exercise is often established in
Irineu Loturco, Lucas A. Pereira, Ciro Winckler, Weverton L. Santos, Ronaldo Kobal, and Michael McGuigan
The load–velocity relationship is widely recognized for its ability to accurately predict the 1-repetition maximum (1RM) in both lower-body and upper-body exercises. 1 – 3 With the data generated by linear-regression models, practitioners can frequently monitor and adjust the resistance
Miguel Sánchez-Moreno, David Rodríguez-Rosell, Fernando Pareja-Blanco, Ricardo Mora-Custodio, and Juan José González-Badillo
Exercise intensity is one of the most important variables to consider when designing resistance training (RT) aimed at improving strength levels. 1 , 2 Traditionally, exercise intensity has been defined and prescribed as a percentage of 1-repetition maximum (%1RM), often called relative intensity
Kamila Grandolfi, Vandre Sosciarelli, and Marcos Polito
The development of muscular strength can be measured by a 1-repetition maximum (1RM) test. 1 Nevertheless, previous studies have shown that some individuals can lift higher loads when 1RM tests are repeated between 1 and 4 days. 2 This is explained by the neural coordination between the motor