Use of Submaximal Repetition Tests for Predicting 1-RM Strength in Class Athletes

Abstract
Twenty-three male college athletes performed submaximal repetition tests (70, 75, 80, 85, 90, and 95% 1-RM) in the bench press (BP), squat (S), and power clean (PC) lifts. For each lift the best predictor of 1-RM strength was defined as the maximal number of repetitions performed at a given lifting intensity (i.e., %1-RM) which represented the highest prediction coefficient (multiple R). ANOVA revealed that regardless of lift, the number of repetitions significantly decreased (p < 0.05) as lifting intensity increased. The best predictor for BP was the number of repetitions performed at 95% 1-RM. For S and PC lifts the best predictors corresponded to the number of repetitions at 80 and 90%, respectively. The S best predictor had the highest prediction power (R2 accounted for 26.9% of the variance). The BP and PC best predictors accounted for 11.6 and 19.1% of the variance, respectively. Although the corresponding best predictors (multiple R) for each lift represented different percentages of 1-RM, their respective predictive power (R2) was not significantly different (p > 0.05). (C) 1996 National Strength and Conditioning Association

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At the second and third visits each subject was randomly assigned to perform either actual or predicted 1-RM testing for both of the exercises. Twelve different prediction methods were used to estimate 1-RM performance from the results. The estimates of 1-RM strength were then compared to actual 1-RM performance to assess the level of conformity between these measures. Statistical procedures including Bland and Altman analyses, intraclass correlation coefficients, typical error and total error of measurement were used in the analyses of the results. In addition, paired t-tests were performed to determine whether actual 1-RM values were significantly different across the control and affected limbs and whether there were any significant differences in predictive accuracy for each equation across the control and affected limbs. Finally, the number of subjects with predicted 1-RM values within 5% or less of their actual 1-RM values was determined for each equation. Results: When the knee injury group performed the knee extension exercise, the Brown, Brzycki, Epley, Lander, Mayhew et al., Poliquin and Wathen prediction methods demonstrated the greatest levels of predictive accuracy. When two atypical subjects were identified and excluded from the analyses, the accuracy of these equations improved further. Following the removal of these two subjects, no significant differences in predictive accuracy were found for any of the equations across the affected and control limbs (p > 0.05). Typical errors and total errors were low for the more accurate prediction methods ranging from 2.4-2.8% and from 2.4-3.5%, respectively. Overall, the Poliquin table appeared to be the most accurate prediction method for this sample (affected limbs: bias 0.3 kg, 95% limits of agreement (LOA) -5.8 to 6.4 kg, typical error as a coefficient of variation (COV) 2.4%, total error of measurement (total error) 2.4%; control limbs: bias -1.3 kg, 95% LOA -9.0 to 6.3 kg, typical error as a COV 2.7%, total error 2.8%). When the knee OA group performed the knee extension exercise, the Brown, Brzycki, Epley, Lander, Mayhew et al., Poliquin and Wathen prediction methods demonstrated the greatest levels of predictive accuracy. No significant differences in predictive accuracy were found for any of the equations across the affected and control limbs (p > 0.05). When an atypical subject was identified and excluded from the analyses, the accuracy of the equations improved further. Typical errors as COVs and total errors for the more accurate prediction methods ranged from 2.5-2.7% and from 2.4-2.9%, respectively. Overall, the Poliquin table appeared to be the most accurate prediction method for this sample (affected limbs: bias 0.9 kg, 95% LOA -4.5 to 6.3 kg, typical error as a COV 2.5%, total error 2.5%; control limbs: bias -0.1 kg, 95% LOA -6.0 to 5.9 kg, typical error as a COV 2.5%, total error 2.4%). When the knee injury group performed the leg press, the Adams, Berger, Lombardi and O’Connor equations demonstrated the greatest levels of predictive accuracy. No significant differences in predictive accuracy were found for any of the equations across the affected and control limbs (p > 0.05). Typical errors as COVs and total errors for the more accurate equations ranged from 2.8-3.2% and from 2.9-3.3%, respectively. Overall, the Berger (affected limbs: bias -0.4 kg, 95% LOA -7.2 to 6.3 kg, typical error as a COV 3.2%, total error 3.2%; control limbs: bias 0.1 kg, 95% LOA -6.6 to 6.7 kg, typical error as a COV 3.1%, total error 3.0%) and O’Connor equations (affected limbs: bias -0.6 kg, 95% LOA-6.8 to 5.7 kg, typical error as a COV 2.9%, total error 3.0%; control limbs: bias -0.2 kg, 95% LOA -6.9 to 6.4 kg, typical error as a COV 2.9%, total error 2.9%) appeared to be the most accurate prediction methods for this sample. When the knee OA group performed the leg press, the Adams, Berger, KLW, Lombardi and O’Connor equations demonstrated the greatest levels of predictive accuracy. No significant differences in predictive accuracy were found for any of the equations across the affected and control limbs (p > 0.05). The typical errors as COVs and the total error values for the more accurate prediction methods were the highest observed in this study, ranging from 5.8-6.0% and from 5.7-6.2%, respectively. Overall, the Adams, Berger, KLW and O’Connor equations appeared to be the most accurate prediction methods for this sample. However, it is possible that the predicted leg press 1-RM values produced by the knee OA group might not have matched actual 1-RM values closely enough to be clinically acceptable for some purposes. Conclusion: The findings of the current study suggested that the Poliquin table produced the most accurate estimates of knee extension 1-RM performance for both the knee injury and knee OA groups. In contrast, the Berger and O’Connor equations produced the most accurate estimates of leg press 1-RM performance for the knee injury group, while the Adams, Berger, KLW and O’Connor equations produced the most accurate results for the knee OA group. However, the higher error values observed for the knee OA group suggested that predicted leg press 1-RM performance might not be accurate enough for some clinical purposes. Finally, it can be concluded that no single prediction equation was able to accurately estimate both knee extension and leg press 1-RM performance in subjects with knee injuries and knee OA.
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    The goal of the present study was to compare traditional (ST) and pyramid (SP) strength training systems during eight weeks on the maximum muscular strength performance. Eighteen experienced in strength training men were divided into two groups of nine volunteers. Four times a week, the ST group trained in three sets of eight repetitions (75% of 1RM) and the SP group in three sets of 10, eight and six repetitions (70%, 75% and 80% of 1RM, respectively). All subjects were submitted to an anthropometric evaluation, followed by 1RM test in the bench press and squat exercises, which were repeated after eight weeks of training. The difference between the attained 1RM for each system was studied using Mann-Whitney test and the Wilcoxon paired test was applied to compare pre- and post-training. No significant differences were recorded between ST and SP bench press (125 ± 19 kg and 120 ± 17.0 kg) and squat (124 ± 18 kg and 120 ± 17 kg). Furthermore, no significant differences were found between the pre- and post-training periods. According to the present results, both training systems produced similar effects on the maximum muscular strength performance.
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    The aim of the present study was to analyze the validation of the equation proposed by Brzycki for the prediction of a maximum repetition (1-RM) in the bench press. Fifty sedentary or moderately active male subjects (22.2 ± 3.5 years; 64.7 ± 8.6 kg), were initially submitted to six test sessions of 1-RM in the bench press, with 48 hours of interval between each session, in order to determine the maximum workload. A protocol of force resistance was then performed for the determination of 7-10-RM. The used criteria for the validation included: t-Student test for dependent samples, for comparison among the mean values obtained by the predictive equation and by the 1-RM test; Pearson correlation coefficient for analysis of the association degree among the measurements; standard error of estimate (SEE) for evaluation of the mean deviation degree of the individual data along the produced line; total error (TE) for the verification of the mean deviation of the individual values of the identity line; constant error (CE) for analysis of the difference among the mean values obtained in the 1-RM test and predicted by the proposed equation. None statistically significant difference was verified among the values produced by the 1-RM test and the Brzycki equation (P > 0.05). Both the SEE and the TE were relatively low (2.42 kg or 3.4% and 1.55 kg or 2.2%, respectively), as well as the CE found (0.22 kg or 0.3%). Moreover, the correlation coefficient value found was extremely high (r = 0.99; P
  • Article
    The aim of the present study was to analyze the validation of the equation proposed by Brzycki for the prediction of a maximum repetition (1-RM) in the bench press. Fifty sedentary or moderately ac-tive male subjects (22.2 ± 3.5 years; 64.7 ± 8.6 kg), were initially submitted to six test sessions of 1-RM in the bench press, with 48 hours of interval between each session, in order to determine the maximum workload. A protocol of force resistance was then per-formed for the determination of 7-10-RM. The used criteria for the validation included: t-Student test for dependent samples, for com-parison among the mean values obtained by the predictive equation and by the 1-RM test; Pearson correlation coefficient for analysis of the association degree among the measurements; standard error of estimate (SEE) for evaluation of the mean deviation degree of the individual data along the produced line; total error (TE) for the verifi-cation of the mean deviation of the individual values of the identity line; constant error (CE) for analysis of the difference among the mean values obtained in the 1-RM test and predicted by the pro-posed equation. None statistically significant difference was veri-fied among the values produced by the 1-RM test and the Brzycki equation (P > 0.05). Both the SEE and the TE were relatively low (2.42 kg or 3.4% and 1.55 kg or 2.2%, respectively), as well as the CE found (0.22 kg or 0.3%). Moreover, the correlation coefficient value found was extremely high (r = 0.99; P < 0.05), thus showing a strong association between the values found by the 1-RM test and the Brzycki equation. Therefore, the equation analyzed by this study satisfied the validation criteria established by the literature. The re-sults suggest that the Brzycki equation seems to be a fairly attrac-tive alternative for the estimation of 1-RM values in the bench press from the performance of submaximal tests of 7-10-RM, in sedentary or moderately active male adults.
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    Strength and Conditioning for Team Sports is designed to help trainers and coaches to devise more effective high-performance training programs for team sports. This remains the only evidence-based study of sport-specific practice to focus on team sports and features all-new chapters covering neuromuscular training, injury prevention and specific injury risks for different team sports. Fully revised and updated throughout, the new edition also includes over two hundred new references from the current research literature. The bookintroduces the core science underpinning different facets of physical preparation, covering all aspects of training prescription and the key components of any degree-level strength and conditioning course, including: ○ physiological and performance testing. ○ strength training. ○ metabolic conditioning. ○ power training. ○ agility and speed development. ○ training for core stability. ○ training periodisation. ○ training for injury prevention. Bridging the traditional gap between sports science research and practice, each chapter features guidelines for evidence-based best practice as well as recommendations for approaches to physical preparation to meet the specific needs of team sports players. This new edition also includes an appendix that provides detailed examples of training programmes for a range of team sports. Fully illustrated throughout, it is essential reading for all serious students of strength and conditioning, and for any practitioner seeking to extend their professional practice.
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    The goal of the present study was to develop an equation for predicting the workload of one maximal repetition (1RM) in wom- en and men, based exclusively on anthropometrical characteris- tics. Forty-four low-risk and experienced in strength training young subjects, being 22 male (23 ± 4 years, 76.6 ± 12.7 kg, 173.9 ± 5.5 cm, 11 ± 4.5% of body fat) and 22 female (22 ± 4 years, 54 ± 6.0 kg, 161 ± 5.8 cm, 18 ± 2.2% of body fat) volunteered for this study. All subjects were submitted to an anthropometrical evaluation fol- lowed by a 1RM familiarization test (shoulder press), which was repeated after 48 h. The repeatability was tested using Wilcoxon Matched paired test. Finally, the 1RM workload was modeled in relation to the anthropometrical variables through multiple linear regression (forward stepwise) using as cutoff criteria for the inde- pendent variables ∆r 2 < 0.01. The models reliability was expressed by the Bland and Altman analysis. All tests assumed α = 0.05. No significant differences were recorded between the two tests, re- sulting 44.6 ± 13.2 kg and 12.2 ± 3.2 kg, for male (MS) and female (FS) subjects respectively. The time of practice in strength training was also included in the models. The model resulted in 84% of explained variance and a standard error of 12% for the MS. On the other hand, for the FS the predictive capacity was weaker than for = the MS, resulting in 56% of the explained variance and a stan- dard error of 20%. In conclusion, the obtained models showed acceptable reliability so that they can be currently used as a tool for predicting the 1RM workload.
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    The objective of the present study was to determine equations that could be used to estimate the load corresponding to the one-repetition maximum (1RM) based on the maximum number of repetitions (MNR) using submaximal loads in bench press, lat machine pull-down and leg curl exercises in strength-trained women (n = 20; 22 ± 3 years; 61 ± 7 kg; 165 ± 4 cm). The first test was the 1RM test. Next, the subjects performed the MNR test at intensities of 70, 80 and 90% of 1RM for all exercises on different days. A multiple linear regression model was used for the determination of each equation. Two criteria were applied to accept the equation: adjusted R2 value (adj.R2 > 0.80) and percent error (PE < 10%). For all exercises, the equations met the two criteria: bench press: adjR2 = 0.89; PE = 5%; lat machine pull-down: adjR2 = 0.84; PE = 5%; leg curl: adjR2 = 0.82; PE = 7%. The application of the equations developed will require the selection of a random load and the number of repetitions performed at the same load to identify 1RM. It is recommended that the number of repetitions be within the range observed in this study: bench press (1-21), lat machine pull-down (2-20), and leg curl (1-14).
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    Grupo SE > PubliC E Standard > Sección: Deportes > Artículo Pid: 331 > Versión Imprimible para Fernando Naclerio Ayllón (fernando.naclerio@uem.es) [Agrandar Letra] [Achicar Letra] [Restablecer] [Imprimir Artículo] RESUMEN Se evaluaron 9 jugadoras de sofball, que realizaron 2 test específicos 1) carrera-home-1º (CH1º), 2) Lanzamiento a home (lz mph), y 2 no específicos, 1) Pres de banca (PB-M), y 2) sentadilla (SP-M), ambos ejecutados en multipower. Se establecieron relaciones entre la velocidad alcanzada en los test específicos y los parámetros " máximos " medidos en los test inespecíficos: Fuerza máxima (FM) potencia media (WM), potencia pico (Wp), velocidad media (Vm) y velocidad pico (Vp) manifestados con diferentes porcentajes de peso. Se encontraron correlaciones significativas entre el test de lz mph con la WM, y Vm en la S-PM; la FM absoluta, y por Kg peso, la Wp por kg Peso, la WM absoluta, y por kg peso, la Vm, y Vp máximas, producidas en el PB-M. Se confirma la importancia del carácter explosivo y específico de los ejercicios de fuerza para mejorar el rendimiento de los gestos específicos Palabras Clave: potencia muscular, deporte de conjunto, capacidades condicionales, rendimiento óptimo. INTRODUCCION La mejora de los niveles de fuerza, potencia, y velocidad, son factores de gran importancia para optimizar el rendimiento en los deportes con gestos explosivos como el softball, en el cual es indispensable la aplicación de un alto nivel de fuerza para alcanzar una altísima velocidad de movimiento contra resistencias muy ligeras. (McBride 2002; Verchoshansky 2002). Estas características deben ser consideradas al realizar los ejercicios de preparación física, donde, todavía no esta bien determinado en que medida el control de la fuerza, velocidad y potencia producida en cada gesto influyen en la eficiencia para mejorar las acciones propias del deporte.(Baker and Nance 1999; Biscioti 2001) En los ejercicios realizados contra resistencias externas que actúan por medio de la gravedad, (masa constante), aunque el sujeto intente siempre aplicar la máxima aceleración, a medida qua aumenta el peso a vencer la velocidad disminuye con una relación casi perfecta respecto el aumento de la magnitud de la resistencia. (Baker 2001ª; Randall Et al 2002) Teniendo en cuenta que las adaptaciones producidas por los entrenamientos de fuerza son especificas no solo respecto a la magnitud de la resistencia utilizada sino también a la velocidad y potencia producida, al elegir los ejercicios de preparación física también es importante considerar que influencia tendrán estos sobre el rendimiento deportivo especifico y cuales son los niveles de fuerza velocidad y potencia adecuados para lograr un aumento del rendimiento especifico. En dos estudios realizados con jugadores de rugby, Baker Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only.
  • Article
    The purpose of this investigation was to compare trunk muscle activity during stability ball and free weight exercises. Nine resistance-trained men participated in one testing session in which squats (SQ) and deadlifts (DL) were completed with loads of approximately 50, 70, 90, and 100% of one-repetition maximum (1RM). Isometric contractions during 3 stability ball exercises (quadruped (QP), pelvic thrust (PT), ball back extension (BE)) were also completed. During all exercises, average integrated electromyography (IEMG) from the rectus abdominus (RA), external oblique (EO), longissimus (L1) and multifidus (L5) was collected and analyzed. Results demonstrate that when expressed relative to 100% DL 1RM, muscle activity was 19.5 +/- 14.8% for L1 and 30.2 +/- 19.3% for L5 during QP, 31.4 +/- 13.4% for L1 and 37.6 +/- 12.4% for L5 during PT, and 44.2 +/- 22.8% for L1 and 45.5 +/- 21.6% for L5 during BE. IEMG of L1 during SQ and DL at 90 and 100% 1RM, and relative muscle activity of L5 during SQ and DL at 100% 1RM was significantly greater (P < or = 0.05) than in the stability ball exercises. Furthermore, relative muscle activity of L1 during DL at 50 and 70% 1RM was significantly greater than in QP and PT. No significant differences were observed in RA and EO during any of the exercises. In conclusion, activity of the trunk muscles during SQs and DLs is greater or equal to that which is produced during the stability ball exercises. It appears that stability ball exercises may not provide a sufficient stimulus for increasing muscular strength or hypertrophy; consequently, the role of stability ball exercises in strength and conditioning programs is questioned. SQs and DLs are recommended for increasing strength and hypertrophy of the back extensors.
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    The number of repetitions subjects could perform when resistive weight for knee flexion exercise was equal to 40, 45, 50, and 55 percent of the strength of the flexor muscles of the knee joint was determined. A resistance load of 55 percent was found satisfactory for obtaining the desired ten repetitions maximum. When compared with available data for knee extension exercise, it was found that while both repetition decrement curves appeared linear, more repetitions were performed for knee flexion exercise at the lighter loads. In addition, more variability and greater strength increases during the exercise program were obtained for knee flexion exercise.