Predicting the Maximum Dynamic Strength in Bench Press: The High Precision of the Bar Velocity Approach

Abstract

Loturco, I, Kobal, R, Moraes, JE, Kitamura, K, Cal Abad, CC, Pereira, LA, and Nakamura, FY. Predicting the maximum dynamic strength in bench press: the high precision of the bar velocity approach. J Strength Cond Res 31(4): 1127-1131, 2017-The aim of this study was to determine the force-velocity relationship and test the possibility of determining the 1 repetition maximum (1RM) in "free weight" and Smith machine bench presses. Thirty-six male top-level athletes from 3 different sports were submitted to a standardized 1RM bench press assessment (free weight or Smith machine, in randomized order), following standard procedures encompassing lifts performed at 40-100% of 1RM. The mean propulsive velocity (MPV) was measured in all attempts. A linear regression was performed to establish the relationships between bar velocities and 1RM percentages. The actual and predicted 1RM for each exercise were compared using a paired t-test. Although the Smith machine 1RM was higher (10% difference) than the free weight 1RM, in both cases the actual and predicted values did not differ. In addition, the linear relationship between MPV and percentage of 1RM (coefficient of determination ≥95%) allow determination of training intensity based on the bar velocity. The linear relationships between the MPVs and the relative percentages of 1RM throughout the entire range of loads enable coaches to use the MPV to accurately monitor their athletes on a daily basis and accurately determine their actual 1RM without the need to perform standard maximum dynamic strength assessments.

The impact of test loads on the accuracy of 1RM prediction using the load-velocity relationship

“…Similarly, our results also suggest that V peak is a more effective measure than V mean when using this technique to predict 1RM in regular (but non-athletic) weight trainers with a mean 1RM Smith Machine bench press approximately equivalent to 1 body weight. While these findings are agreement with earlier research [ 20 , 25 ] other studies favour V mean [ 24 , 26 ], highlighting that the specific loading regime influences this outcome.…”

“…Although these movements are more common in high performance training programs, the use of a Smith Machine and appropriately trained “ Spotters ” means that these exercises can be completed safely with novice participants (NB: some Smith Machines contain a pneumatic brake which prevents the bar from descending rapidly – hence improving exercise safety). Although 1RM data recorded on Smith Machines are typically 10% higher than those recorded using free weights, there are no significant differences between predicted 1RM values when using these devices [ 20 ]. These protocols also have the advantage of being relatively quick to perform as they involve loads between 30 and 80% of 1RM [ 11 , 16 , 21 ] being lifted as rapidly as possible for only 2–4 repetitions.…”

Reliability of the velocity achieved during the last repetition of sets to failure and its association with the velocity of the 1-repetition maximum

“…In the present study we also explored the influence of 1RM strength on the values of V 1RM and V last . Based on the lower V 1RM reported by Helms et al (2017) in powerlifters during the free-weight BP (0.10 ± 0.04 m·s −1 ) compared to the V 1RM reported by Loturco et al (2017) in rugby players and combat athletes (0.17 m·s −1 ), we hypothesized that the 1RM strength would be negatively associated with V 1RM and V last . This hypothesis was somewhat supported with a significant, albeit weak, negative correlation between the 1RM load and V 1RM (r = −0.33) and V last (r = −0.17).…”

The Role of Velocity Based Training in the Strength Periodization for Modern Athletes

“…All studies reported the presence of a high-qualified supervisor during the training session or protocols used. Three studies specified the periodization used during the intervention period: linear periodization [11,14] and traditional strength-power periodization [18]. All studies indicated concurrent training methods with more than one aspect trained at the same time: technical/tactical, power, strength, speed, and energy system development.…”

“…Previous studies with strength and top-level athletes have related the velocity of the bar and load lifted, proving the validity of the estimation of 1RM percentage based on movement velocity [1,11]. The two necessary key components to prescribe VBT are the percentage of loss of velocity and the mean concentric velocity of the fastest repetition (which is related to the loading magnitude) [1].…”