Physiological response on 1 RM bench press performance

Abstract

A number of methods for determining upper body maximal strength are present. The 1-RM is defined as the maximum amount of resistance that can be performed for only 1 repetition and it has been shown to be reliable in various populations. Further, setting an intensity of resistance training based on a percentage of the 1-RM has been found to be effective for improving outcomes such as muscle strength, muscle power, and muscle hypertrophy. Little is known about the metabolic cost of 1RM evaluation and which is the optimal recovery time between sessions. We analyzed the physiological response during a standardized protocol of 1RM-Bench Press Test (1RM-BP). Fourteen healthy subjects (25,6±7,4 yrs; 166,3±0,9 cm; 65,6±13,2 kg) performed a 1RM-BP following standardized procedures. VO2 and Heart Rate ware measured before, during and after the BP performance while Systolic (Sys) and Diastolic (Dys) pressure were measured only before and after the test. At the e! nd of the 1RM-BP , Blood Lactate (BL)was assessed and participants were asked for perceived exertion according with the Borg Scale (RPE). The protocol consisted of five steps; 15 repetitions with � of the subjects body weight were performed in the first step, subsequently weight was added up to ½ of bodyweight and a maximal number of repetitions were performed. In the third step the participants executed the theoretical 1RM-BP according to the Mayhew’s formula that considers the number of repetitions completed with ½ bodyweight of each subject. The other steps ware performed only if the third one was completed, if not 2-5% more weight was added on the barbell until 1RM was obtained, this was repeated if necessary for a maximum of other 2 times. The results show that there are no significant differences in VO2 values between male and female, only in the second step (½ Bodyweight) males achieve higher results (p=0,0032). BL was significantly! higher in male(p=0,042) even if %Lean mass was not quite significantly higher than female(p=0,0532). The most interesting result is shown by Pearson’s correlation between %Lean mass vs 1RM-BP; male were positively correlated( r=0,61) while female were negatively (r=-0,65). Unexpected results need to be confirmed by a larger number of participants, but at this stage this study shows that in any case there are gender differences. Furthermore, this study confirms the reliability, feasibility and safety of the 1RM-BP.