Acute Effects of Variable-Resistance and Free-Weight Bench Pull Exercise in Resistance-Trained Men

Participants completed the high-load variable-resistance bench-pull condition during the first experimental session and the high-load free-weight bench-pull condition during the second experimental session. The two sessions were separated by 72 hours. In each session, the high-load bench pull was followed after 3 minutes by three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum.

Participants performed one set of three bench-pull repetitions at approximately 85% of their free-weight one-repetition maximum. External resistance was provided by a combination of barbell load and chains, with the chains contributing approximately 20% of the effective mean total load. Participants were instructed to perform the concentric phase with maximal intended velocity. After the high-load bench pull, participants rested for 3 minutes and then completed three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum, with 3-minute rest intervals between sets. Each subsequent set was terminated when mean repetition velocity fell below 0.65 m·s-¹ or when the prescribed range of motion could not be completed.

Participants performed one set of three bench-pull repetitions at approximately 85% of their free-weight one-repetition maximum, with the external resistance provided entirely by the barbell. Participants were instructed to perform the concentric phase with maximal intended velocity. After the high-load bench pull, participants rested for 3 minutes and then completed three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum, with 3-minute rest intervals between sets. Each subsequent set was terminated when mean repetition velocity fell below 0.65 m·s-¹ or when the prescribed range of motion could not be completed.

Participants completed the high-load free-weight bench-pull condition during the first experimental session and the high-load variable-resistance bench-pull condition during the second experimental session. The two sessions were separated by 72 hours. In each session, the high-load bench pull was followed after 3 minutes by three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum.

Participants performed one set of three bench-pull repetitions at approximately 85% of their free-weight one-repetition maximum. External resistance was provided by a combination of barbell load and chains, with the chains contributing approximately 20% of the effective mean total load. Participants were instructed to perform the concentric phase with maximal intended velocity. After the high-load bench pull, participants rested for 3 minutes and then completed three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum, with 3-minute rest intervals between sets. Each subsequent set was terminated when mean repetition velocity fell below 0.65 m·s-¹ or when the prescribed range of motion could not be completed.

Participants performed one set of three bench-pull repetitions at approximately 85% of their free-weight one-repetition maximum, with the external resistance provided entirely by the barbell. Participants were instructed to perform the concentric phase with maximal intended velocity. After the high-load bench pull, participants rested for 3 minutes and then completed three standardized free-weight bench-pull sets at approximately 75% of one-repetition maximum, with 3-minute rest intervals between sets. Each subsequent set was terminated when mean repetition velocity fell below 0.65 m·s-¹ or when the prescribed range of motion could not be completed.

Movement velocity was measured using a linear position transducer sampling at 100 Hz. Mean velocity and peak velocity were obtained for each of the three repetitions performed during the high-load bench-pull set. For each loading condition, average mean velocity and average peak velocity were calculated by averaging the corresponding values across the three repetitions. Velocity was expressed in meters per second (m·s-¹).

Surface electromyography was recorded from the right latissimus dorsi, teres major, posterior deltoid, and middle trapezius. Root mean square amplitudes were normalized to the maximal root mean square amplitude obtained during maximal voluntary isometric contraction testing and expressed as a percentage of maximal voluntary isometric contraction (%MVIC). Mean and peak electromyography amplitudes were obtained for each repetition and averaged separately across the three high-load repetitions.

Participants completed three subsequent free-weight bench-pull sets at approximately 75% of one-repetition maximum. Each set was terminated when the mean velocity of a repetition fell below 0.65 m·s-¹ or when the participant was unable to complete the prescribed range of motion. The number of valid repetitions completed in each of the three sets was recorded.

Mean and peak velocity were measured during each of the three subsequent free-weight bench-pull sets. For the repetition-matched analysis, velocity outcomes included average velocity, fastest-repetition velocity, matched-final velocity, velocity maintenance, and velocity decline. Repetition matching was performed separately for each participant and corresponding set using the smaller number of valid repetitions completed across the two experimental conditions.

Mean and peak surface electromyography amplitudes were assessed for the right latissimus dorsi, teres major, posterior deltoid, and middle trapezius during each of the three subsequent free-weight bench-pull sets. Electromyography amplitudes were normalized to maximal voluntary isometric contraction and expressed as %MVIC. For the repetition-matched analysis, mean and peak amplitudes were averaged separately across all included repetitions within each set.