The examination of a different range of motion (ROM) during the barbell-bench press exercises on glycolytic metabolism, muscle oxygenation and biomechanical measures of force and power

Introduction: Full range of motion (fROM) during resistance training (RT) is a traditionally recommended by professionals as approach for optimal strength and muscle adaptations. However, newer research has shown that partial range of motion (pROM) has similar benefits. Purpose: The purpose of this study is to investigate the effect of a range of motion (fROM vs. pROM) during both flat (FB) and incline (IB) barbell bench exercises press on acute markers of oxygen saturation (SmO2) of the pectoralis major (PM), blood lactate (BLa), and simple biomechanical markers of vertical distance (cm), peak force (N), absolute peak power (W), peak velocity (m/s), and relative power (W/kg). Methods: Two male and female subjects (Age:22.2±0.9y; Height:170.0±3.4cm; Weight:71.3±7.1kg; Body Fat:17.60±4.2%) were subsequently randomized to perform both ROM bouts during IB-bench press (45° incline) and FB-bench press utilizing a Smith Machine (SM) barbell machine. The SM barbell was adjusted per subject’s preferred arm length. 7-days prior to each ROM bout, strength testing (1RM) was completed to determine 75-80% intensity used for the subsequent ROM bouts. Pre-bout (Pre) and immediate post-bout (IP) BLa was measured as an indirect marker to determine glycolytic contribution. A Moxy Muscle Oxygen monitor was placed on the subjects right PM at 25% distal to the suprasternal notch to assess SmO2 (n=1). The biomechanical measures were collected using a commercially available GymAware PowerTool Linear position transducers (GLT) that directly measures the vertical displacement of a cable that was attached to the SM barbell and is expressed through and saved on an iPad. A one-way ANOVA was used to assess any preliminary differences. Results: Currently, no differences were found in BLa change ( ) and volume load (sets·reps·kg) (n=4); No differences were found in any biomechanical measure including vertical distance between conditions; SmO2 showed the lowest O2 saturation in the pROM-IB condition. Discussion/Conclusion: Currently, there are no differences found between conditions. However, this may be explained by loss of subject GymAware data due to recent update made to their application. No difference was found between conditionings in vertical distance. However, this could be explained by differing arm lengths of the participants. Lastly, a small sample size at this time limits any significant conclusions.