Influence of the “Slingshot” Bench Press Training Aid on Bench Press Kinematics and Neuromuscular Activity in Competitive Powerlifters

Abstract

This study examined the acute effects of the 'Slingshot' on bench-press performance, prime-mover surface electromyographic (sEMG) amplitude, and barbell velocity during maximal and submaximal bench-pressing in competitive male powerlifters. Fifteen male powerlifters (mean ± SD age: 27.05 ± 5.94 years; mass: 94.15kg; 1RM bench-press: 139.7 ± 16.79kg) participated in the study. Bench-press strength, average barbell velocity, and sEMG amplitude of the prime mover muscles (triceps brachii, pectoralis major and anterior deltoid) were measured during two conditions; 'Raw' (without use of any assistance) and 'Slingshot' [using the 'Slingshot' to perform both the weight achieved during 'Raw' 1RM testing (Raw max/SS), and absolute 1RM using the 'Slingshot' (SS)]. The results showed that the 'Slingshot' significantly increased bench press 1RM performance by a mean ± SD of 20.67kg ± 3.4kg. Barbell velocity and stick point analysis indicate that this improvement is likely driven by an increase in peak and pre-stick barbell velocity as triceps RMS was lower throughout all rep max phases with the 'Slingshot'. The 'Slingshot' also caused reductions in RMS, specifically of the triceps at all rep ranges but barbell velocity was better maintained in the last reps of all sets. These data indicate that the 'Slingshot' specifically de-loaded the triceps muscle throughout all rep ranges and provide assistance to maintaining barbell velocity under fatigue during later repetitions of multiple-repetition sets. The 'Slingshot' training aid could therefore be used in de-load phases of bench press training or as an over-reaching and velocity training aid.

The ‘Slingshot’ can enhance volume-loads during performance of bench press using unaided maximal loads

“…Indeed, this might be further compromised for larger individuals as bench press 1RM with the Slingshot is closely related to body mass possibly due to the greater stretch and stored elastic energy that can be utilised in the Slingshot (R 2 = 0.334). 8 In fact, in retrospective analysis of our results in light of this we also found that body mass was closely related to the increase in volume-load performed with the Slingshot whilst using an unaided 1RM load (R 2 = 0.518). However, there may still be benefits to utilising the Slingshot in terms of enhancing skill development and bench press kinematics.…”

“…Indeed it may be that the use of the Slingshot forces the user to adopt a more advantageous position for both grip width and elbow position to reduce the influence of the typical sticking point which occurs during the bench press. Indeed, Dugdale et al 8 corroborate this suggesting that the sticking point position was shifted subtly when using the Slingshot compared to when not. Thus, the greater volumeload that can be achieved during use of the Slingshot with unaided maximal loads might permit greater practice of the correct kinematics involved with successful bench pressing.…”

“…7,8 Further, when using the Slingshot to lift the loads attained during an unaided bench press 1RM there is an increased bar velocity, even during predicted 3RM attempts, further suggesting that fatigue is reduced. 8 This suggests that the Slingshot may in fact be resulting in a lower relative demand during the bench press exercise and that this is one of the reasons for the enhanced performance in terms of both the ability to use 'supramaximal' loads and to attain higher volume-loads with unaided 1RM loads. Increased volume-load has been argued to be important in enhancing both strength through practice as well as hypertrophy by maximising mechanisms involved with such adaptation.…”

“…A recent study in powerlifters has also reported similar findings. 8 Strength is thought to be highly specific and as such, if the goal is to improve strength as tested with a specific task, such as a 1RM, training with loads that are similar, if not the same, will optimise this outcome. 9,10 Indeed, success in the bench press is determined by optimising the kinematics of the lift where not only can the shortest bar path be achieved in order to be biomechanically efficient 11 , but also economical in terms of neuromuscular effort 12 .…”

“…Anecdotally, it has been suggested that the Slingshot device could also allow individuals to perform multiple repetitions (~3-5) using their unaided 1RM loads and that this increase in the volume-loads possible at higher loads may facilitate adaptation. Indeed, Dugdale et al 8 reported a strong correlation between unaided bench press 1RM and the load participants could use in a predicted 3RM whilst employing the Slingshot. As noted, strength gains are highly specific and the increase in possible volume (3-5 repetitions) may not achieve traditional volumes associated with attainment of maximal hypertrophy.…”