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USING BENCH PRESS LOAD TO PREDICT UPPER BODY EXERCISE LOADS IN PHYSICALLY ACTIVE INDIVIDUALS  [cached]
Del P. Wong,Kwan-Lung Ngo,Michael A. Tse,Andrew W. Smith
Journal of Sports Science and Medicine , 2013,
Abstract: This study investigated whether loads for assistance exercises of the upper body can be predicted from the loads of the bench press exercise. Twenty-nine physically active collegiate students (age: 22.6 ± 2.5; weight training experience: 2.9 ± 2.1 years; estimated 1RM bench press: 54.31 ± 14.60 kg; 1RM: body weight ratio: 0.80 ± 0.22; BMI: 22.7 ± 2.1 kg·m-2) were recruited. The 6RM loads for bench press, barbell bicep curl, overhead dumbbell triceps extension, hammer curl and dumbbell shoulder press were measured. Test-retest reliability for the 5 exercises as determined by Pearson product moment correlation coefficient was very high to nearly perfect (0.82-0.98, p < 0.01). The bench press load was significantly correlated with the loads of the 4 assistance exercises (r ranged from 0.80 to 0.93, p < 0.01). Linear regression revealed that the bench press load was a significant (R2 range from 0.64 to 0.86, p < 0.01) predictor for the loads of the 4 assistance exercises. The following 6RM prediction equations were determined: (a) Hammer curl = Bench press load (0.28) + 6.30 kg, (b) Barbell biceps curl = Bench press load (0.33) + 6.20 kg, (c) Overhead triceps extension = Bench press load (0.33) - 0.60 kg, and (d) Dumbbell shoulder press = Bench press load (0.42) + 5.84 kg. The difference between the actual load and the predicted load using the four equations ranged between 6.52% and 8.54%, such difference was not significant. Fitness professionals can use the 6RM bench press load as a time effective and accurate method to predict training loads for upper body assistance exercises.
Shoulder Muscle Activation of Novice and Resistance Trained Women during Variations of Dumbbell Press Exercises  [PDF]
Joshua Luczak,Andy Bosak,Bryan L. Riemann
Journal of Sports Medicine , 2013, DOI: 10.1155/2013/612650
Abstract: Previous research has compared the effects of trunk inclination angle on muscle activation using barbells and Smith machines in men. Whether similar effects occur with the use of dumbbells or in women remains unknown. The purpose was to compare upper extremity surface electromyographical (EMG) activity between dumbbell bench, incline, and shoulder presses. Dominate arm EMG data were recorded for collegiate-aged female resistance trained individuals ( ) and novice female resistance trained exercisers ( ) from which average EMG amplitude for each repetition phase (concentric, eccentric) was computed. No significant differences were found between experienced and novice resistance trained individuals. For the upper trapezius and anterior deltoid muscles, shoulder press activation was significantly greater than incline press which in turn was significantly greater than bench press across both phases. The bench and incline presses promoted significantly greater pectoralis major sternal activation compared to the shoulder press (both phases). While pectoralis major clavicular activation during the incline press eccentric phase was significantly greater than both the bench and shoulder presses, activation during the bench press concentric phase promoted significantly greater activation than the incline press which in turn was significantly greater than the shoulder press. These results provide evidence for selecting exercises in resistance and rehabilitation programs. 1. Introduction Variations of the bench press are commonly used weight training exercises for strength and power development of the muscles in and around the chest and shoulder areas. For example, although the bench press is most often performed with a standard barbell and stable flat bench, dumbbells and machines can also be used as sources of resistance along with unstable surfaces (i.e., cushions and Swiss balls) to produce similar press actions with varying intensity and stabilization demands. Understanding the mechanical demands imposed by each bench press variation assists with matching the patient/client needs with the specific characteristics of each exercise he/she completes. Changing the angle of trunk inclination during variations of bench pressing exercises changes the line of action of the resistance relative to the trunk and, in turn, changes the direction of the movement force provided by the shoulder muscles. Based on the arrangement of the shoulder muscles, accommodation to these changes in bench inclination is thought to promote maximal activation of the muscles active during
A kinetic and Kinematic analysis in two assessment situation with bench press. Free Weight vs Smith Machine. Project pilot. ANáLISIS CINéTICO Y CINEMáTICO DEL PRESS DE BANCA EN DOS SITUACIONES DE EVALUACIóN: PRESS BANCA LIBRE VS PRESS BANCA MáQUINA SMITH. PROYECTO PILOTO [A kinetic and Kinematic analysis in two assessment situation with bench press. Free Weight vs Smith Mach]  [cached]
I. J. Bautista,I. J. Chirosa,J. Arguelles,J. M. Monje
E-balonmano.com : Revista de Ciencias del Deporte , 2012,
Abstract: This pilot study examines the most relevant kinetic and kinematics variables in two bench press exercises; Smith Machine (PMS) vs. free weights (PBL). Two trained subjects participated in the research following informed consent. To determine the maximum load (1-RM), two incremental protocols were used for PMS and PBL. Subject 1 (S-1) produced force values of 770N and 837N, peak force of 28ms and 12ms, in PBL and PMS respectively. Values for subject 2 (S-2) were 693N and 849N, PMF of 60ms and 66ms for PBL and PMS respectively. Detailed analyses of the following variables were performed; velocity curves for each load, the “sticking period”, the distances of grip width, and changes in bar inclination during the ascent phase of the lift were examined. The key findings of this research, and the basis for future research demonstrate that PBL is recommended as a training exercise, while more reliable information regarding force variables can be attained through using PMS in measurement sessions. Key Words: Bench Press, smith machine, free weight, strength assessment, upper limb. En este estudio piloto se analizan algunas de las variables cinéticas y cinemáticas que pueden afectar a la situación de ejecución/evaluación del Press de Banca, en máquina Smith (PMS) vs con barra y discos (PBL). Dos sujetos entrenados participaron en esta investigación habiendo sido informados previamente de la finalidad de la misma. En dos momentos se llevó a cabo un protocolo incremental de cargas hasta alcanzar su máximo peso a desplazar en una repetición (1-RM), uno para el PMS y otro para el PBL. El Sujeto 1 (S-1) manifestó valores de fuerza de 770 y 837 N, en PBL y PMS, alcanzando este pico máximo de fuerza (PMF) a los 28 y 12 ms, respectivamente. En el caso del Sujeto 2 (S-2), los valores de PMF fueron de 693 y 849 N, empleando un tiempo en alcanzar estos PMF fue de 60 y 66 ms, en PBL y PMS, respectivamente. Se realizó un análisis detallado de las curvas de “sticking period”, las distancias de agarre e inclinación de la barra. Como conclusión más relevante de nuestro trabajo y como base para futuras investigaciones, decir que a la hora de entrenar, el ejercicio en PBL puede ser más aconsejado. Mientras que para evaluar, el ejercicio en PMS aporta información más fiable en cuanto a las variables relevantes de la fuerza. Palabras Clave: Press de banca, máquina Smith, peso libre, evaluación de la fuerza, tren superior.
PEDOMETER ACCURACY DURING STAIR CLIMBING AND BENCH STEPPING EXERCISES  [cached]
Makoto Ayabe,Junichiro Aoki,Kojiro Ishii,Kohsaku Takayama
Journal of Sports Science and Medicine , 2008,
Abstract: The purpose of the present investigation was to examine pedometer accuracy during stair climbing and descending as well as during the performance of a bench stepping exercise. Ten healthy men participated in the present investigation. All subjects ascended and descended an 18 cm high public staircase, and performed a bench stepping exercise by using a 10, 20 and 30 cm high platforms, while wearing three different commercial pedometers (DW-800, YM, HJ- 700IT; OM, Lifecorder; KZ). In both situations, the stepping rate was controlled at 40, 50, 80, 100 and 120 steps·min-1. The pedometer scores tended to underestimate the actual number of steps during stair climbing with a slower stepping rate and/or the lower height of a platform. During the stair ascending and descending and the bench stepping exercise using 20 to 30 cm high platforms at 80 to 120 steps·min-1, the magnitude of the measurement error was -3.8 ± 10. 8 % for KZ, -2.1 ± 9.8 % for YM and -11.0 ± 18.9 % for OM. These results indicate that the KZ and the YM can accurately assess the number of steps during stair climbing using 20 to 30 cm high platforms at 80 to 120 steps·min-1
VALIDITY OF A COMMERCIAL LINEAR ENCODER TO ESTIMATE BENCH PRESS 1 RM FROM THE FORCE-VELOCITY RELATIONSHIP  [cached]
Laurent Bosquet,Jeremy Porta-Benache,Jér?me Blais
Journal of Sports Science and Medicine , 2010,
Abstract: The aim of this study was to assess the validity and accuracy of a commercial linear encoder (Musclelab, Ergotest, Norway) to estimate Bench press 1 repetition maximum (1RM) from the force - velocity relationship. Twenty seven physical education students and teachers (5 women and 22 men) with a heterogeneous history of strength training participated in this study. They performed a 1 RM test and a force - velocity test using a Bench press lifting task in a random order. Mean 1 RM was 61.8 ± 15.3 kg (range: 34 to 100 kg), while 1 RM estimated by the Musclelab's software from the force-velocity relationship was 56.4 ± 14.0 kg (range: 33 to 91 kg). Actual and estimated 1 RM were very highly correlated (r = 0.93, p<0.001) but largely different (Bias: 5.4 ± 5.7 kg, p < 0.001, ES = 1.37). The 95% limits of agreement were ±11.2 kg, which represented ±18% of actual 1 RM. It was concluded that 1 RM estimated from the force-velocity relationship was a good measure for monitoring training induced adaptations, but also that it was not accurate enough to prescribe training intensities. Additional studies are required to determine whether accuracy is affected by age, sex or initial level.
Functional profile determination "trained" and "untrained" by the speed of the bar on the bench press DETERMINACIóN DEL PERFIL FUNCIONAL “ENTRENADOS” Y “NO ENTRENADOS” SEGúN LA VELOCIDAD DE LA BARRA EN EL PRESS DE BANCA [Functional profile determination "trained" and "untrained" by the speed of the bar on the bench press]  [cached]
W. Albarracín,I Bautista,L. J. Chirosa,I. Martín
E-balonmano.com : Revista de Ciencias del Deporte , 2012,
Abstract: A descriptive study was designed to explore differences in strength, power and velocity in an incremental load protocol in bench press (PB), to obtain an indicator to catalogue a subject as “trained“ or “untrained” in the PB exercise.. Thirty male subjects consisted two groups, “trained group”, consisted of the participants whose one repetition maximum (1RM) exceeded his body weight (BW) and “untrained group” consisted of participants whose 1RM was less than their BW. The value of 1RM was 82.33 ± 11.09 kg and 59.67 ± 5.16 kg, in the trained and untrained groups, respectively. The indicator of the level of strength (kg 1RM / kg BW) in the trained group was greater than 1, and lower in the untrained group. The average strength showed significant differences (p < 0.05) in the 60, 80% and 1RM. Average power and peak power were higher in the trained group in all analyzed intensities, with the exception of the 1RM. Average velocity and peak velocity showed significant differences between the two groups in the first two intensities analyzed. The main conclusion of this study is provides a functional profile of subjects as “trained”, when the 1RM and BW ratio is equal to or greater than 1 (1RM>BW), while when this ratio is less than 1 (1RMKeywords: 1RM, Evaluation of the strength, functional profile, manifestations of strength. Un estudio descriptivo fue dise ado para explorar diferencias en fuerza, potencia y velocidad, en un protocolo incremental de cargas en press de banca (PB), de esta forma se pretendió obtener un indicador para catalogar el perfil de un sujeto como “entrenado” y “no entrenado” en el ejercicio del PB. Treinta participantes varones conformaron los grupos; “grupo entrenados” conformado por los participantes con una repetición máxima (1RM) superior a su peso corporal (BW) y “grupo no entrenados” conformado por los participantes con 1RM menor a su BW. El valor de 1RM fue 82.33 ± 11.09 kg y 59.67 ± 5.16 kg, en el grupo entrenados y no entrenados respectivamente. El indicador del nivel de fuerza (kg 1RM / kg BW) en el grupo entrenados fue superior a 1 e inferior en el grupo no entrenados. La fuerza media mostró diferencias significativas (p < 0.05) al 60, 80% y 1RM. La potencia media y el pico máximo de potencia, fueron mayores en el grupo entrenados en todas las intensidades analizadas, exceptuando en 1RM. La velocidad media y el pico máximo de velocidad mostraron diferencias significativas entre ambos grupos en las dos primeras intensidades analizadas. La principal conclusión de este estudio, es proporcionar un perfil funcional de los sujetos
Influência do processo de familiariza??o para avalia??o da for?a muscular em testes de 1-RM
Dias, Raphael Mendes Ritti;Cyrino, Edilson Serpeloni;Salvador, Emanuel Péricles;Caldeira, Lúcio Flávio Soares;Nakamura, Fábio Yuzo;Papst, Rafael Raul;Bruna, Nelson;Gurj?o, André Luiz Demantova;
Revista Brasileira de Medicina do Esporte , 2005, DOI: 10.1590/S1517-86922005000100004
Abstract: although the use of maximum repetition tests (1-rm) is frequent for assessment of the muscular strength, one believes that the results obtained may be affected by the lack of previous familiarization, even in skilled subjects in exercises with weights. thus, the objective of this study was to investigate the impact of the familiarization process on the muscular strength assessment in 1-rm tests. to do so, 21 men (24.5 ± 3.8 years of age), apparently healthy and with previous experience of at least six months on weight training, were submitted to repetitive tests of 1-rm in bench press, squat, and arm curl exercises. the tests were performed in four sessions with intervals every 48-72 hours. a maximum number of three attempts with 3-5 minutes interval for recovery was used in each exercise in the four testing sessions. the analysis of variance anova for repeated measures followed by the post hoc tukey test when p < 0.05 were used for the data treatment. significant increases on the muscular strength (p < 0.01) were found in the three exercises analyzed between the first and the fourth familiarization session (2.4% in bench press, 3.4% in squat, and 5.4% in the arm curl). however, no statistically significant difference was found between the second and fourth familiarization sessions in the arm curl (p > 0.05) as well as between the third and fourth sessions in the bench press and squat (p > 0.05). the results indicate that the lack of previous familiarization with 1-rm tests may impair the muscular strength evaluation. therefore, the performance of two to three familiarization sessions in adult men with previous experience with weightlifting is suggested for a more accurate muscular strength assessment by means of the 1-rm tests.
Critically appraised paper: Benefits of motor imagery training on muscle strength.
Pramod D Shenoy
Journal of Physical Therapy , 2010,
Abstract: It is well established that motor imagery (MI) improves motor performance and motor learning efficiently. Previous studies provided evidence that muscle strength may benefit from MI training, mainly when movements are under the control of large cortical areas in the primary motor cortex. The purpose of this experiment is to assess whether MI might improve upper and lower limbs’ strength through an ecological approach and validation, with complex and multi-joint exercises. Nine participants were included in the MI group and 10 in the control (CTRL) group. The 2 groups performed identical bench press and leg press exercises. The MI group was instructed to visualize and feel the correspondent contractions during the rest period, whereas the CTRL group carried out a neutral task. The maximal voluntary contraction (MVC) and the maximal number of repetitions (MR) using 80% of the pre-test MVC weight were measured. Although both MI and CTRL groups enhanced their strength through the training sessions, the leg press MVC was significantly higher in the MI group than in the CTRL group (p< 0.05). The interaction between the leg press MR and the group was marginally significant (p = 0.076). However, we did not find any difference between the MI and CTRL groups; both in the bench press MVC and MR. MI-related training may contribute to the improvement of lower limbs performance by enhancing the technical execution of the movement, and the individual intrinsic motivation. From an applied and practical perspective, we state that athletes may perform imagined muscles contractions, most especially during the rest periods of their physical training, to contribute to the enhancement of concentric strength.The author provides a detailed critique of the published paper by Lebon et al section-wise in a truly scientific style.
Minimizing weighted mean flow time in open shop scheduling with time-dependent weights and intermediate storage cost
Seyed Hossein Hashemi Doulabi,Amir Ardestani jaafari,Mohsen Akbarpour Shirazi
International Journal on Computer Science and Engineering , 2010,
Abstract: Open shop scheduling problem is a common scheduling problem and has wide engineering applications in manufacturing. In some industrial cases, open shop scheduling could be a long scheduling problem as anaircraft production. In these cases, time value of money plays a significant role in determining a schedule cost. This paper addresses the problem of minimizing sum of weighted mean flow time and intermediate storage cost in an open shop scheduling environment. The main contribution of this work is to concern time-dependent weights which results in a more realistic insight for decision makers via considering time value of money in long scheduling problems. We haveformulated the problem as a mixed integer linear programming model. Due to the nondeterministic polynomial time complexity of the problem, a novel genetic algorithm is also presented to solve the problem in reasonable time. Computational results indicate remarkableimprovement of the objective function as compared with the case of having constant weights over scheduling horizon.
Compara??o entre o desempenho motor de homens e mulheres em séries múltiplas de exercícios com pesos
Salvador, Emanuel Péricles;Cyrino, Edilson Serpeloni;Gurj?o, André Luiz Demantova;Dias, Raphael Mendes Ritti;Nakamura, Fábio Yuzo;Oliveira, Arli Ramos de;
Revista Brasileira de Medicina do Esporte , 2005, DOI: 10.1590/S1517-86922005000500002
Abstract: the magnitude of men and women's neuromuscular, metabolic, and morphologic responses seems to be quite different even when both are submitted to exercise protocols using similar weight exercises protocols. however, differences in the motor performance between men and women have been predominantly reported in protocols based on isometric and isokinetic contractions. thus, this study aimed to analyze men and women's behavior during multiple sets of weight exercises achieving the exhaustion, and later verifying possible differences as to the physical performance between genders using weights with similar intensity. for this, 83 subjects (50 men, and 33 women), 48 hours after being submitted to 1-rm tests in bench press, squat and arm curl performed a protocol composed by four sets at 1-rm 80% up to achieving the exhaustion in each of three exercises to evaluate the endurance ability to the fatigue in different muscular groups. it was used the anova and ancova for repeated measurements, followed by the tukey's post hoc test, where p < 0.05 to the data treatment. it was verified a significant fall in the performance both in men and in women since the first up to the fourth sets of every exercise investigated (p < 0.01). although the fatigue magnitude was higher in men in all the three exercises, the effect on the gender was only identified in the arm curl exercise (p < 0.01). the results of this study indicated that men and women presented quite different behavior in multiple sets of weight exercises, and women presented a more stable performance and a higher endurance ability to the fatigue in the arm curl as well.
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