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

February 2019
The Journal of Strength and Conditioning Research 33(2):327-336

DOI:10.1519/JSC.0000000000001853

Authors:

James H Dugdale

Edinburgh Napier University

Angus M Hunter

Nottingham Trent University

Thomas George Di Virgilio

University of Stirling

Lewis James Macgregor

University of Stirling

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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.

. Participant characteristics.* Subject characteristics were measured as mean 6 SD

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INFLUENCE OF THE “SLINGSHOT”BENCH PRESS

TRAINING AID ON BENCH PRESS KINEMATICS AND

NEUROMUSCULAR ACTIVITY IN COMPETITIVE

POWERLIFTERS

JAMES H. DUGDALE,ANGUS M. HUNTER,THOMAS G. DIVIRGILIO,LEWIS J. MACGREGOR,AND

D. LEE HAMILTON

Physiology, Exercise and Nutrition Research Group, Faculty of Health Sciences and Sport, University of Stirling, Stirling,

United Kingdom

ABSTRACT

Dugdale, JH, Hunter, AM, Di Virgilio, TG, Macgregor, LJ, and

Hamilton, DL. Inﬂuence of the “Slingshot” bench press training

aid on bench press kinematics and neuromuscular activity in

competitive powerlifters. J Strength Cond Res 33(2): 327–

336, 2019—This study examined the acute effects of the

“Slingshot” (SS) 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 6SD; age: 27.05 65.94 years; mass: 94.15 6

13.43 kg; 1 repetition maximum [1RM] bench press: 139.7

616.79 kg) 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 2 conditions; “Raw” (without

use of any assistance) and “SS” (using the “Slingshot” to per-

form both the weight achieved during “Raw” 1RM testing

[Raw max/SS], and absolute 1RM using the “SS”). The re-

sults showed that the “SS” signiﬁcantly increased bench

press 1RM performance by a mean 6SD of 20.67 63.4

kg. Barbell velocity and stick point analysis indicate that this

improvementislikelydrivenbyanincreaseinpeakandpres-

tick barbell velocity as triceps root mean square (RMS) was

lower throughout all rep max phases with the “SS.” The “SS”

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 “SS”

speciﬁcally deloaded the triceps muscle throughout all rep

ranges and provide assistance to maintaining barbell velocity

under fatigue during later repetitions of multiple repetition

sets. The “SS” training aid could therefore be used in deload

phases of bench press training or as an overreaching and

velocity training aid.

KEY WORDS stick point, stick period, powerlifting

INTRODUCTION

The bench press is one of the most used exercises

within strength and conditioning practice and pro-

gramming (22). Similar to other free weight resis-

tance exercises, the bench press is used for

developing maximal strength, power, and hypertrophy (31).

The bench press is also one of the 3 competition lifts within

the sport of powerlifting (IPF, 2015). However, the popularity

of the bench press is because of its ability to develop the

strength, power, and hypertrophy of the prime movers: the

pectoralis major, anterior deltoid, and triceps brachii

(13,21,24,26). Several studies demonstrate the transfer of

bench press strength to improvements in motor unit recruit-

ment through various planes of the shoulder (13,14), and

more importantly for athletic performance, strength in the

bench press is an indicator of performance in strength and

power sports (10,11,23). Therefore, developing strategies to

improve bench press performance has the potential to

improve performance across a range of sports including but

not limited to powerlifting, discus throwing (10), swimming

(11), and kayaking (23).

When training for an increase in strength, several

training methods and strategies can be adopted. With

regard to speciﬁcity and technical practice, it is important

to perform the full movement itself; however, there is

a growing trend to use supplementary or assistance training

to develop the muscles, movement patterns, or weak points

within a given exercise (29,30,35). A recent survey of com-

petitive powerlifters demonstrated that more than 50% are

using resistance bands in their bench press training, more

so than alternative supplementary training methods such as

the use of chains (30).

Address correspondence to D. Lee Hamilton, d.l.hamilton@stir.ac.uk.

33(2)/327–336

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Ó2017 National Strength and Conditioning Association

VOLUME 33 | NUMBER 2 | FEBRUARY 2019 | 327

Elastic resistance training primarily involves the use of elastic

bands of varied thicknesses to challenge a movement pattern

and align with the force capability of the musculature

throughout the range of motion of many movement tasks

(29,35). Several studies demonstrate that the use of combined

elastic resistance training in the bench press improves the devel-

opment of upper-body strength (1,8,13,18), and in addition,

a recent meta-analysis supports the efﬁcacy of variable resis-

tance training methods (use of bands and chains) to improve

measures of maximal strength (28). Despite the increased pop-

ularity and evidence for the use of elastic resistance training, far

less attention has been focused on elastic assistance training.

Elastic assistance training uses an assistance or an over-

speed approach during the performance of athletic and

strength training movements, allowing an athlete to run faster,

jump higher, or lift more weight than they could do without

the assistance (7,32). Several studies demonstrate that elastic

assistance acutely improves jump height (32) and sprinting

performance (7), whereas chronic jump training with elastic

assistance for 4 weeks signiﬁcantly improved jump perfor-

mance compared with training without assistance (3). Relative

to research on elastic resistance devices, much less attention

has been given to the implementation of elastic assistance

devices for upper-body strength performance.

A recent study examined the acute effects of implementing

a supportive assistance device called the “Slingshot (SS),” on 1

repetition maximum (1RM) bench press performance in 19

resistance trained male participants (36). The study observed

the effect of the “SS” in comparison with traditional “Raw”

bench press performance, and report signiﬁcant increases to

1RM and barbell velocity associated with trends for decreased

electromyographic (EMG) amplitude for both the pectoralis

major and triceps brachii. They reported that all participants

showed an increase in absolute 1RM performance by an aver-

age of ;16 kg while wearing the “SS,” and that participants

were able to execute their “Raw” 1RM weight at signiﬁcantly

higher barbell velocity and power output when using the “SS.”

However, when the relative intensity was matched between

the absolute “Raw” vs. “SS,” 1RM average barbell velocity and

average power output were not statistically different and there

was a trend for the prime mover normalized EMG amplitude

to be lower while wearing the “SS” despite the heavier load.

These data indicate that the “SS” was assisting participants to

lift either heavier loads or equal loads at a greater velocity,

whereas the trends for decreased EMG amplitude suggest

potential deloading in the prime movers.

We therefore assessed bench press kinematics and neuro-

muscular activation during maximal and submaximal bench

pressing with or without the “SS” in trained powerlifters.

Our aim was to use stick point analysis (9,33) in conjunction

with EMG assessments to try to understand the mechanism

by which the “SS” improves 1RM, and the inﬂuence it may

have on matched intensity submaximal sets. We hypothe-

sized that the improvement in 1RM with the “SS” would be

because of either (a) an increased normalized surface EMG

(sEMG) amplitude of the prime movers during or after the

stick period of the bench press or (b) that the improvement

would be because of a greater peak and average velocity in

the early phases of the bench press as a result of the elastic

assistance provided by the “SS.” As a secondary hypothesis,

we also theorized that the “SS” would maintain barbell

velocity during sets with multiple repetitions.

METHODS

Experimental Approach to the Problem

This study used a within-subjects design to examine the

effects of Mark Bell’s original “SS” on maximal and submax-

imal bench press kinematics and neuromuscular activity. The

study was designed to assess how using the elastic assistance

device, the “SS,” altered neuromuscular recruitment patterns

of the prime movers and the kinematics of the bench press

during maximal and submaximal efforts. These measure-

ments will allow us to determine the mechanism by which

the “SS” may be working and illustrate what affect it may

have on muscle recruitment.

Subjects

The methods and procedures implemented within this study

were approved by the University of Stirling, School of Sport

Research Ethics Committee, and all participants provided

written informed consent on recruitment selection. All

testing took place at the Gannochy Sports Center—Athlete

Performance Laboratory, at the University of Stirling, United

Kingdom. Fifteen male competitive powerlifters (Table 1;

subject characteristics) voluntarily participated in this study.

Participants were contacted through word of mouth, social

media, and through study advertisement from 2 drug-tested

TABLE 1. Participant characteristics.* Subject characteristics were measured as mean 6SD

Age

(y)

Mass

(kg)

Height

(cm)

Bench press

1RM (kg)

Training

age (y)

Training

sessions/wk (d)

N= 15 27.05 65.94 94.15 613.43 177.38 64.33 139.73 616.79 5.93 65.67 4.2 60.53

*All participants were recruited from UK drug tested power lifting federations and had at least 2 years of powerlifting-based

strength training experience.

Impact of the Slingshot on Bench Press Performance

328

Journal of Strength and Conditioning Research

the

powerlifting federations within the United Kingdom. Partic-

ipants were selected based on having $2 years of

powerlifting-based strength training. All participants were

considered healthy and injury-free based on their responses

to a Physical Activity Readiness Questionnaire and under-

stood no reason as to why their ability to exert maximal

bench press force would be limited in any way.

Procedures

The study consisted of 2 laboratory-based trials of ;1.5 hours

each. Trials were scheduled between 7 to 14 days apart and

were completed at the same time of day to account for circa-

dian variation (4). During each

trial, participants’ 1RM bench

press was measured, followed

by a predicted 3RM (3Rep) at

87.5% of achieved 1RM and

3 submaximal sets of 8 repeti-

tions (8Rep) at 70% of achieved

1RM (2). All participants com-

pleted the “Raw” trial ﬁrst

(without the use of the SS),

followed by the “SS” trial.

All bench press attempts were

completedonasolidleather

competition height bench

secured in position inside

aFT700PowerCage(Fit-

ness Technology, Melbourne,

Australia), and using an IPF

speciﬁcation Eleiko PL competition barbell (Eleiko,

Halmstad, Sweden), Eleiko WL colored training disks (Eleiko),

and Eleiko Olympic WL competition collars (Eleiko).

Before commencing the initial trial, participants were pro-

vided with a 3-day training and food diary, and asked to

complete both diaries in the 2 days leading up to, and day of

testing. Participants were advised to maintain their normal diet

and training habits and to avoid completing the bench press

exercise 48 hours before testing. Before the second trial,

participants were provided with their original diaries and

advised to replicate their activities to the upmost of their ability.

On arrival to the laboratory, participants provided anthro-

pometric measurements comprising their age (years), body

mass (kilograms), and height (centimeters), along with

a competition-style bench press 1RM (kilograms) predicted

to the best of their ability. Participants were also allowed to

select their preferred rack height, and demonstrated their

bench press grip width, which was measured and recorded

(centimeters) and marked for reference on the barbell using

masking tape.

Before commencing any warm-up activities, participants

were familiarized with the testing protocol and require-

ments, and allowed to ask any questions or for any further

information, if required. During the initial phase of the

warm-up, all participants were required to familiarize

themselves with the sEMG normalization procedure by

completing controlled and consistent bench press repetitions

using the empty barbell to a metronome set at 30 b$min

before loading. During this familiarization, a clearly audible

metronome was played through a pair of speakers, and par-

ticipants were required to complete a full competition style

set-up, unrack the barbell, and perform as many repetitions

as they deemed necessary until they felt conﬁdent executing

the bench press movement to the rhythm of the metronome.

Each time the metronome sounded indicated a change of

phase (eccentric:concentric), requiring a controlled time

period of 2 seconds per phase.

Figure 2. Electrode placement and positioning of the “Slingshot (SS).”

Participants were instructed to wear the “SS” with the crease centered

at the elbow. Electrodes were placed as described in the methods to

ensure that the “SS” did not disrupt the electrodes during bench

pressing.

Figure 1. “Slingshot” placement during a representative repetition. Subjects were instructed to perform the “SS”

repetitions to the same International Powerlifting Federation (IPF) standards as in the previous “Raw” trials.

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VOLUME 33 | NUMBER 2 | FEBRUARY 2019 | 329

After the metronome familiarization, the barbell was

loaded for participants and they performed repetitions at

various increments of their choosing. Number of sets,

repetitions, and loadings were recorded on a data collection

sheet for replication in the subsequent trial and rest intervals

of 2 minutes were provided throughout the warm-up. For

normalization purposes, participants were recorded per-

forming 1 set of 5 repetitions at 70% of predicted 1RM to

the 30 b$min

metronome, following the criteria high-

lighted above (6). After the single normalization set, partic-

ipants continued with their own self-selected warm-up.

Once participants exceeded 90% predicted 1RM, all

attempts were considered “1RM attempts” and were com-

pleted between 5-minute rest intervals and to correct referee

commands and competition rules (IPF, 2015). Participants

proceeded with 1RM attempts in increments of their choos-

ing and in agreement with the primary investigator until they

reached muscular or technical failure. In all instances, 1RM

was achieved between 3 and 5 attempts. Attempts were dis-

qualiﬁed if the participant failed to successfully perform the

repetition or if they failed to meet all competition require-

ments for successful bench press performance (IPF, 2015)

(Figure 1). Once participants had established a 1RM, they

performed 3 consecutive paused repetitions at 87.5% 1RM to

demonstrate execution of a predicted 3 repetition maximum

(3Rep) with consideration to fatigue accumulated following

the 1RM protocol (2). Participants ﬁnally completed 3 sets of

8 continuous and dynamic repetitions (8Rep) using 70%

1RM (2). Multiple repetition sets were also separated by

a 5-minute rest interval and assistance racking and unracking

the barbell was provided at the participants’ choosing.

Following the 7- to 14-day interval, participants returned

to the laboratory and completed the SS trial. Participants

were provided with an introduction to the SS, and, identical

to trial 1, participants’ anthropometric characteristics were

taken and a refamiliarization to the procedures was provided

before commencing the warm-up. Several different size se-

lections were provided for the “SS” device, and were ﬁtted to

each participant according to the manufacturer’s instruc-

tions. The same warm-up protocol was followed, and an

identical rack height and grip width was implemented. All

warm-up before, and including normalization repetitions

were taken without the use of the “SS,” and all repetitions

performed following the 70% normalization were completed

using the “SS.” The “SS” was worn across the elbow joint as

recommended by the product manufacturers, and to avoid

Figure 3. Deﬁning the phases of maximal bench press attempts. Figure 3 illustrates a representative trace of acceleration, velocity and displacement during a 1

repetition maximum (1RM) attempt. The beginning of the prestick period (phase 1) was identiﬁed as the point at which velocity was 0 m$sec

at the end of the

eccentric phase. The stick point and the beginning of the stick period (phase 2), was identiﬁed as the point of peak velocity during the concentric phase. The

poststick period (phase 3) began when acceleration again crossed 0 m$sec

. The poststick period ended when velocity reached 0 m$sec

at the end of the

concentric phase.

Impact of the Slingshot on Bench Press Performance

330

Journal of Strength and Conditioning Research

the

disruption to EMG signals on the triceps and pec place-

ments (Figure 2). The achieved Raw 1RM weight was per-

formed as one of the “SS” 1RM attempts (Raw max/SS),

participants then proceeded to add weight and follow the

same protocol as the “Raw” trial until a separate “SS” 1RM

was achieved. Participants’ 3Rep and 8Rep weight were es-

tablished using 87.5% and 70% of the achieved “SS” 1RM,

respectively, and were performed in the same manner

described for the “Raw” trial.

All attempts throughout both

trials were performed to the

nearest 1 kg.

Surface EMG amplitude was

collected by skin surface elec-

trodes (SilveRest, Vermed, VT)

from the pectoralis major, ante-

rior deltoid, and triceps brachii

of the participants’ dominant

side during all repetitions using

a BioPac MP100 (BioPac Sys-

tems, Inc., Santa Barbara, CA,

USA). Reference signals were

provided via skin surface elec-

trodes placed on the clavicularis

and patella. Before applying the

electrodes, the skin surface was

prepared for collection by shav-

ing, slightly abrading using

sandpaper, and wiped with

alcohol swabs (PDI Healthcare,

Orangeburg, NJ, USA), in line

with SENIAM guidelines (16).

A small amount of SignaGel

electrode gel (Parker Laborato-

ries, Fairﬁeld, NJ, USA) was

used on the center of each elec-

trode to aid signal quality. Elec-

trodes were applied to the skin

surface ;2 cm apart and

secured to the skin surface with

masking tape, if necessary.

Because of the nature and

placement of the “SS,” electro-

des for the pectoralis major

were placed using medial and

central clavicularis placements

as suggested by Krol et al., (19)

(Figure 2). Electrode placement

for both the anterior deltoid

and triceps brachii were in line

with recommendation by Perot-

to and Delagi (25). As partici-

pants performed bench press

repetitions, the EMG amplitude

of the pectoralis major, anterior

deltoid, and triceps brachii (root mean square; RMS) was

collected using the Acqknowledge software for Windows

(BioPac Systems, Inc.) and saved for ofﬂine analysis.

A Celesco PT5A-125-S47-UP-10K-M6 linear transducer

(Celesco, Toronto, ON, Canada), connected to a BioPac

MP100 data capture unit (BioPac Systems, Inc.), was secured

to the top of the power rack to measure participants’ average

barbell velocity (m$sec

) and bar displacement (centimeters)

Figure 4. The “Slingshot” (SS) increases the bench press 1 repetition maximum (1RM) in a manner correlated to

body mass. Fifteen trained powerlifters underwent rep max testing on 2 occasions separated by 7–14 days. The

“Raw” repetition maximum (1RM) was determined without any assistance and the SS repetition maximum was

determined while wearing the “SS.” After the 1RM testing, 3 repetitions (3Rep) were performed at 87.5% of the

achieved 1RM followed by 3 sets of 8 (8Rep) at 70% of the achieved 1RM. The mean weight lifted in each of

these conditions is plotted in (A) with the individual 1RM data plotted on the inset graph. The absolute gain from

wearing the “SS” (the difference between Raw and SS trials) was plotted against the Raw 1RM achieved (B) and

against the body mass of the individuals (C). The individual data for the Raw 1RM and the weight lifted on the

3Rep SS trial were plotted (D) with a linear regression of these variables plotted in (E). *Signiﬁcantly different from

corresponding “Raw” condition (as assessed by paired t-test between respective “Raw” and “SS” conditions).

Signiﬁcance was determined as p#0.05.

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VOLUME 33 | NUMBER 2 | FEBRUARY 2019 | 331

during all bench press attempts. During both “Raw” and “SS”

trials, a Velcro strap attached to the transducer cable was

secured in a consistent, slightly off center placement on the

barbell. The position of the transducer was adjusted appro-

priately for each participant so that the cable ran vertically

during bench press execution. As participants performed

bench press repetitions, the velocity and displacement of

the barbell was recorded using the Acqknowledge software

for Windows (BioPac Systems, Inc.) and saved for ofﬂine

analysis.

All data were analyzed using the Acqknowledge software

for Windows (BioPac Systems, Inc.). Repetition phases were

deﬁned in accordance with (9,34). Surface EMG signals for

the pectoralis major, anterior deltoid, and triceps brachii

were digitized individually at a sampling rate of 2,000 Hz

and recorded in volts. Surface EMG signals were RMS pro-

cessed based on previous recommendations for research

investigating neuromuscular activation levels (15). Average

RMS was calculated for a moving window 100-millisecond

time period across the entire waveform for each activity. The

sEMG signals were then normalized against corresponding

repetitions extracted from the set of 5 reps performed to

a metronome at 70% 1RM (6) as part of the participants’

warm-up.

Analysis of the transducer data was performed by

highlighting only the concentric phase of the repetitions.

Phases were deﬁned in accordance with Van den Tillaar and

Ettema (34). For both maximal and submaximal repetitions,

the start of the concentric phase was identiﬁed as the ﬁrst

point at which velocity reached 0 m$sec

, indicating

a change of direction. For maximal attempts, the phases of

the concentric portion of the bench press were deﬁned as

per Van Den Tillaar and Ettema (34) (Figure 3 for represen-

tative trace). This involved deﬁning the beginning of the

prestick period (phase 1) by identifying the point at which

velocity was 0 m$sec

at the end of the eccentric phase,

identifying the stick point and beginning of the stick period

(phase 2) as the point of peak velocity during the concentric

phase, and identifying the poststick period (phase 3) as the

point at which acceleration again crossed 0 m$sec

. The lift

ended when velocity reached 0 m$sec

at the end of the

concentric phase. Each phase and/or repetition was ana-

lyzed individually for total time (seconds), average bar speed

(m$sec

), and the stick point was identiﬁed (meters) com-

parative to the total displacement.

Statistical Analyses

All statistical analyses were carried out in GraphPad Prism

(GraphPad Software, La Jolla, CA, USA). Where 2 groups

were compared, a 2-tailed t-test was performed. Where more

than 2 groups were compared, a 1-way analysis of variance

(ANOVA) was used with a Tukey’s HSD test. Where multiple

comparisons were made across groups, a 2-way ANOVA was

performed with a Bonferroni’s multiple comparisons test.

Normality of data was tested using D’Agostinio-Pearson

omnibus normality test. Where data were not normally dis-

tributed, then the nonparametric 2-tailed t-tests were per-

formed. When multiple comparisons were made on

nonnormal data, then a Friedman test was used with a Dunn’s

multiple comparisons test. All data were reported as mean 6

SEM and signiﬁcance was set as p#0.05. Correlations were

determined via a simple linear regression.

Figure 5. The “Slingshot” (SS) reduces surface electromyographic

(sEMG) amplitude of the triceps brachii at all intensities. The “Raw max/

SS” was performed during the warm-up of the SS trial day and consisted

of performing the previous session’s raw 1RM while wearing the “SS.”

Surface EMG amplitudes were recorded during all sets and reps as

described in the Methods. All data presented are root mean square

(RMS) processed and normalized to the 70% normalization set. A) The

sEMG amplitudes recorded during repetition maximum testing; (B)

sEMG amplitudes recorded during the set of 3 repetitions at 87.5%; and

70%. F= “Raw” is signiﬁcantly different from both “Raw max/SS” and

“SS” (as assessed by multiple comparisons); a= signiﬁcantly different

from “SS” (as assessed by multiple comparisons); § = signiﬁcantly

different from “Raw” (as assessed by multiple comparisons); * =

signiﬁcantly different from “raw” (assessed by paired t-test). Signiﬁcance

was determined as p#0.05. Tricep = triceps brachii, pec = pectoralis

clavicularis, Delt = anterior deltoid, grouped = sEMG grouped for all 3

muscles assessed.

Impact of the Slingshot on Bench Press Performance

332

Journal of Strength and Conditioning Research

the

RESULTS

All participants displayed an increase in absolute bench

press performance while using the “SS” from 139.7 64.34

kg “Raw” to 160.4 64.43 kg “SS” for an average increase of

;20 kg (Figure 4A). The absolute gain from the “SS” was

not related to the amount lifted (Figure 4B) but instead was

highly correlated to the individuals bodyweight (R

0.334), indicating that despite all participants wearing an

appropriately sized device, the

larger participants were able to

gain more from the “SS” (Figure

4C). The “Raw” 1RM corre-

sponded closely to the calcu-

lated “SS” 3Rep (Figure 4D).

These data were plotted and

correlated revealing that there

was a highly signiﬁcant correla-

tion between participant’s

“Raw” 1RM and “SS” 3Rep

= 0.954) (Figure 4E).

During maximal 1RM

bench press attempts, “Raw”

normalized triceps RMS

(169.64 615.26%) was signif-

icantly higher than both “Raw

max/SS” and “SS” conditions

(87.28 65.84% and 115.84 6

10.64%) (Figure 5A). Normal-

ized RMS for the pectoralis

was signiﬁcantly lower in the

“Raw max/SS” condition com-

pared with the “SS” condition

(90.83 66.97% vs. 117.8 6

11.27%) during 1RM attempts

(Figure 5A). Normalized RMS

for all muscles (grouped) was

signiﬁcantly reduced during

1RM performance for “Raw

max/SS” (95.58 65.47%) than

during the “Raw” condition

(138.82 69.42%) (Figure 5A).

Normalized triceps RMS was

also observed to be signiﬁ-

cantly higher during the

“Raw” condition (126.02 6

9.19%) than the “SS” condi-

tion (83.12 69.97%) during

a set of 3 repetitions (Figure

5B), and during both set 1

(108.15 66.25% vs. 75.96 6

7.36%) and set 3 (115.35 6

7.48% vs. 84.37 68.45%) of

the multiple sets of 8 repeti-

tions (Figure 5C).

Average barbell velocity was signiﬁcantly greater across

the whole concentric phase by ;3-fold for the “Raw max/

SS” condition (0.29 60.02 m$sec

) compared with the

“Raw” and “SS” conditions (0.11 60.01 m$sec

and

0.10 60.01 m$sec

) (Figure 6A). The peak velocity during

the maximal attempts was signiﬁcantly higher in the “SS”

condition compared with the “Raw” condition (0.31 60.02

m$sec

vs. 0.27 60.02 m$sec

), as was the average veloc-

ity of phase 1 (Figure 6A). There is a trend for phase 3 to

Figure 6. The “Slingshot (SS)” improves peak barbell velocity on maximal efforts and maintains mean barbell velocity

in multiple repetition sets. Barbell velocity was tracked during all movements using a vertical transducer. The phases

of the bench press were determined by assessing the acceleration curves with the stick period deﬁned as the period

between negative and positive barbell acceleration. A)Barbell velocity during rep max testing. B) Individual changes in

barbell velocity between “Raw” and “SS” trials assessed by phases of the maximal effort. C) Barbell displacement

during maximal efforts with the displacement at which the stick point occurs and also the displacement over which the

stick period lasts also plotted. D) The % of the total displacement at which the stick period begins (stick point) and the

% displacement over which the stick period lasts plotted as individual responses from the “Raw” to the “SS” trials. E)

Average barbell velocity for each repetition of the set of 3 reps at 87.5%. F) The % decrement in barbell velocity from

repetition 1 to repetition 3 on the “Raw” and “SS” trials. G) Average barbell velocity for the ﬁrst and last rep of the ﬁrst

and last set of the 3 sets of 8 repetitions at 70%. H) The % decrement in barbell velocity from repetition 1 to repetition

8 on the third set of the “Raw” and “SS” trials. F=“Raw” is signiﬁcantly different from both “Raw max/SS” and “SS”;

a= signiﬁcantly different from “Raw” (assessed by multiple comparisons); e= signiﬁcant difference between 2 bars

(assessed by multiple comparisons); * = signiﬁcantly different from “Raw” (assessed by paired ttest). Signiﬁcance

was determi ned as p#0.05.

Journal of Strength and Conditioning Research

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VOLUME 33 | NUMBER 2 | FEBRUARY 2019 | 333

have a lower velocity in the “SS” condition compared with

“Raw.” There is a high degree of variability between the “SS”

and “Raw” conditions when plotting these data as individual

responses, while during phase 1 there is a consistent increase

in phase 1 velocity (9 subjects increase) when wearing the

“SS” (Figure 6B).

The displacement data demonstrates that there was no

effect of wearing the “SS” on total displacement indicating

that hand position was replicated accurately between trials

and that the “SS” did not affect the range of motion (Figure

6C). However, the “SS” signiﬁcantly altered the displacement

at which the stick point occurred (Figure 6C). The effect was

small, ;1 cm higher in the concentric phase, but very consis-

tent with 12 of 15 subjects demonstrating an upward shift in

the start of the stick point (Figures 6C, D). The sticking period

tended to occupy a greater proportion of the concentric phase

while wearing the “SS”; however, this did not reach signiﬁ-

cance. While not signiﬁcant, when the individual data were

plotted as percentage of the total displacement, there was

a similar trend but a high degree of intersubject variability,

with 7 subjects demonstrating an increase and 8 subjects dem-

onstrated a decrease in the stick period length while wearing

the “SS” (Figure 6D).

No signiﬁcant differences were found for average barbell

velocity (m$sec

) during reps 1 and 2 of the 3Rep; how-

ever, the average barbell velocity was signiﬁcantly faster for

the “SS” condition than the “Raw” condition (0.21 60.02

m$sec

vs. 0.18 60.02 m$sec

) during rep 3 of the 3Rep

(Figure 6E). Similarly, the change in barbell velocity (%)

between reps 1 and 3 of the 3Rep were signiﬁcantly lower

in the “SS” than the “Raw” condition (215.72 65.36% vs.

225.57 69.4%) (Figure 6F). Average barbell velocity was

signiﬁcantly faster during the “SS” than the “Raw” condition

for both set 1 rep 8 (0.35 60.04 m$sec

vs. 0.30 6

0.04 m$sec

) and set 3 rep 8 (0.34 60.07 m$sec

vs.

0.26 60.03 m$sec

) during the multiple sets of 8 repeti-

tions (Figure 6G). Similarly, the change in barbell velocity

(m$sec

) between reps 1 and 8 of the multiple sets of 8 were

signiﬁcantly lower in the “SS” than the “Raw” condition

(219.38 64.4% vs. 231.18 64.82%) (Figure 6H).

To determine the mechanism behind the improved 1RM

performance while wearing the “SS,” we split the analysis of

the prime mover RMS over the 3 phases of the bench press;

prestick period [1], stick period [2], and poststick period [3].

These data revealed that there was no effect of the “SS” on

pectoralis (Figure 7B) or deltoid (Figure 7C) RMS activation.

However, the triceps RMS was signiﬁcantly lower during the

stick [2] and poststick [3] periods (Figure 7A).

DISCUSSION

This is the ﬁrst study to assess the impact of the “SS” bench

press training aid on bench press kinematics and neuromus-

cular activity in comptetitive powerlifters across a range of

intensities. The “SS” was found to be an effective elastic

assistance device for enhancing 1RM bench press perfor-

mance in all participants, on average producing a ﬁxed abso-

lute increase of ;20 kg. This elastic assistance allowed the

“Raw” 1RM to be lifted with an average velocity ;33faster

than the “Raw” 1RM performed unassisted. The increased

velocity while wearing the “SS” occurred despite signiﬁ-

cantly reduced RMS in the triceps brachii. Furthermore,

when intensity was matched (same relative %1RM with or

without the “SS”), the RMS of the triceps was reduced at all

intensities. During both the multiple repetition conditions

(3Rep/8Rep), the last rep was performed with a higher

velocity than the corresponding “Raw” condition. This

Figure 7. The “Slingshot (SS)” reduces surface electromyographic

(sEMG) amplitude of the triceps brachii during a maximal effort. Surface

EMG amplitudes were recorded during repetition maximum testing as

described in the Methods. All data presented are root mean square

(RMS) processed and normalized to the 70% normalization set. A)

sEMG amplitudes of the triceps brachii, (B) sEMG amplitudes of the

pectoralis clavicularus, and (C) sEMG amplitudes of the anterior

deltoids. a= signiﬁcantly different from “SS” (as assessed by multiple

comparisons p#0.05).

Impact of the Slingshot on Bench Press Performance

334

Journal of Strength and Conditioning Research

the

preservation of barbell velocity throughout a set may be

indicative of reduced fatigue (27), suggesting that despite

matching for relative intensity, the “SS” may effectively

reduce fatigue.

Componentsofthevelocitydatafromourstudyare

somewhat reminiscent of the velocity data obtained from

performing the bench press with chain weight (5). At the

beginning of the concentric phase, the assistance from the

device will likely be greatest, and like with chains, the force

required to move the bar off the chest will be lower with

the weight experienced increasing into lockout. Therefore,

increased velocity is an attractive theory for the mechanism

of how the “SS” may work. Despite the greater load, the

average barbell velocity of the maximal lift was the same

between conditions, with peak barbell velocity signiﬁcantly

faster during a maximal attempt with the “SS.” Assessing

barbell velocity during the different pressing phases re-

vealed that during the prestick period [1], barbell velocity

was signiﬁcantly faster while wearing the “Slingshot.” The

velocity data yield some insight into the mechanism by

which the “SS” may allow an individual to complete a full

lift with signiﬁcantly more weight than their “Raw” 1RM.

We initially theorized that as the concentric phase pro-

gressed, the activation of the prime movers would increase

to compensate for the reducing assistance supplied by the

elastic device. To our surprise, the RMS of the pectoralis

and the deltoids was the same between the “Raw” and “SS”

conditions, whereas the RMS of the triceps was signiﬁ-

cantly reduced in the “SS” trial. These data indicate that

despite ;20kgextraonthebar,thetricepsarehavingto

activate to a lesser extent to complete the lift, even during

the poststick [3] phase of the lift where the assistance from

thedevicewouldbeassumedtobeminimal.Wehypothe-

size that the ability to complete the repetition with a signif-

icantly greater load during the “SS” trial is driven by both

the increased peak velocity, and increased velocity

throughout the prestick [1] period imparting more

momentum to the barbell. However, it is unlikely that

increased velocity is the mechanism responsible for every

individual, as several individuals display a reduced velocity

during the prestick period [1]. As a result, we must explore

additional theories as to how the “SS” allows individuals to

lift signiﬁcantly higher loads, despite similar, and in some

cases reduced, prime mover sEMG.

One possibility is that the “SS” may alter the mechanics of

the bench press by pulling the elbows into a more mechan-

ically advantageous position. Van den Tillaar and Ettema

(34) suggest that the stick period during the bench press is

partly because of the arm position transitioning into a less

mechanically advantageous position. It is possible that

because of the nature and placement of the “SS,” that it

may be maintaining the elbows in a position, which may

allow for a stronger press. Another possibility for how the

“SS” alters the bench press performance is that the “SS”

shifts the displacement at which the stick period begins.

While the shift in where the stick period begins was small,

;1 cm higher during “SS” vs “Raw,” we cannot rule out the

possibility that this small shift may have had a signiﬁcant

effect on the ability to complete the lift.

The study by Ye et al., (36), similar to ours, found a ﬁxed

increase in 1RM performance from wearing the “SS.” They

observed an increase in absolute 1RM performance from

114.6 to 132.1 kg and a ﬁxed mean increase of 17.6 kg while

wearing the “SS.” Our ﬁndings, however, showed that the

“SS” improved mean 1RM bench press performance from

139.7 to 160.4 kg with a mean ﬁxed increase of 20.67 kg.

Although largely similar, the slight differences in ﬁndings

between our study and those of Ye et al., (36) are possibly

due to the training status and technical competency of the

different sample groups. As in our study, they also found no

correlation between the 1RM and the gain from wearing the

“SS.” These data indicate that the weight lifted while wearing

the “SS” is not related to the amount of weight on the bar. We

ﬁnd, however, that the mass of the individual is signiﬁcantly

correlated to the gain from wearing the “SS.” The range in

gain from wearing the “SS” in our study was 15–27 kg with

the greatest gain achieved by the largest (by body mass) indi-

vidual in the study (124.1 kg). We theorize that this effect may

be driven by chest girth, i.e., greater chest girth creating

a greater stretch producing more elastic assistance. Future

studies should correlate more comprehensive anthropometric

measures to the gain from wearing the “SS,” thus allowing for

an individual to estimate the gain they will get from the device

by making a simple anthropometric measure.

PRACTICAL APPLICATIONS

Aside from suggesting how the “SS” works, our data also

suggest some potential uses for the device in training. Some

researchers have theorized that the beneﬁt of elastic training

is that it allows for similar forces to be produced but at faster

velocities (20). The “SS” could be used as a speed training

device, as our data clearly demonstrate that velocity is sub-

stantially improved while wearing the “SS.” Therefore, it

may have some utility in velocity training for sports such

as the shotput. However, the sEMG data shows that the

triceps are very likely deloaded at all intensities with the

“SS.” These ﬁndings combined with the velocity data from

the multiple repetition sets suggest that the “SS” likely re-

duces fatigue and could also be used as a deloading tool. One

advantage of the “SS” over other deloading or speed training

tools, such as using bands and chains, is its ease of use.

Furthermore, unlike other commonly used deloading tools,

the “SS” allows for a full range of motion to be performed as

demonstrated by total barbell displacement during both

“Raw” and “SS” trials. It should be noted that if the “SS”

was used for a bulk of training, that the potential deloading

of the triceps would very likely lead to a reduced perfor-

mance on the bench press; therefore, it should be used stra-

tegically and as a supplement to traditional bench press

training.

Journal of Strength and Conditioning Research

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VOLUME 33 | NUMBER 2 | FEBRUARY 2019 | 335

In summary, the acute increases observed in bench press

performance resultant of using the “SS” suggest that it may

be an effective training device for speed training and deload-

ing the bench press exercise during a variety of intensities

while maintaining the full range of motion of the traditional

format of the bench press.

ACKNOWLEDGMENTS

This study was conducted without any ﬁnancial support and

we have no conﬂicts of interest. The results of this study do

not constitute endorsement of the product by the authors or

the NSCA. The authors gratefully acknowledge expert

technical assistance for Mr Chris Grigson. The authors are

indebted to the volunteers who gave their time to this study.

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The Effects of the "Sling Shot" Device on Bench Press Performance, Mechanical Properties of Muscle, and Movement Kinematics

Article

Jun 2022
J STRENGTH COND RES

This study aimed to evaluate the influence of the sling shot support device at various external loads and intensities of effort, taking into account acute changes in power performance, mechanical muscle properties, and bench press kinematics. For this purpose, 12 resistance-trained men (age: 27.1 ± 4.2 years, body mass: 90.3 ± 16.9 kg, bench press [BP] 1 repetition maximum [1RM]: 112.7 ± 23.1 kg, resistance training experience: 6.9 ± 3.8 years) participated in the study. Each subject completed 2 experimental sessions that differed in the use of the sling shot (SS) or nonuse (CONT) of the SS and an appropriate external load. The 2 experimental sessions consisted of the 1RM test, 3 sets of 2 repetitions of BP with the load increased in each set (50-70-90% 1RM), and a fourth set of the BP efforts to muscle failure with a 70% 1RM load. Before and after each set, the changes in triceps brachii oscillation frequency and stiffness were assessed by means of myotonometry. Results indicated a significant main effect of the SS to increase peak power (p < 0.0001, n = 0.733). Furthermore, a significantly higher 1RM (129 ± 26 vs. 113 ± 23 kg, p < 0.001, effect size [ES]: 0.63), number of repetitions (15 ± 3 vs. 13 ± 2, p = 0.013, ES: 0.76), and time under tension (34 ± 10 vs. 29 ± 6 seconds, p = 0.017, ES: 0.59) were found during the set to failure for SS in comparison to the CONT condition. Moreover, there was a significant main effect of time to increase oscillation frequency (p = 0.001; n = 0.666) and stiffness (p = 0.002; n = 0.613) from pre-to postset measure. In addition, the main effect of the side (p = 0.034; n = 0.348) was reported to show higher stiffness on the dominant than on the nondominant side in the CONT condition. The results suggest that an independent 1RM measurement and a correspondingly higher workload are required to take full advantage of the SS device. Moreover, the SS can also be used successfully to increase training volume and the involvement of nondominant limbs during a bench press.

Training with an elastic, supportive bench press device is not superior to a conventional training approach in trained menTraining mit einer elastischen Bankdrückhilfe ist einem konventionellen Trainingsansatz bei trainierten Männern nicht überlegen

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May 2021

The aim of this study was to investigate the effects of an 8‑week powerlifting-type bench press (BP) resistance training (RT) program, either without (RAW) or with using a supportive elastic bench press device (EBD) on one-repetition maximum (1-RM), body weight (BW), mid-upper arm and chest circumference, as well as visual analogue pain scale (VAS) of the shoulder, elbow, and wrist. For this purpose, a matched pair parallel design based on initial 1‑RM was used (BPD n = 16, age 24.4 ± 4 years, RT experience 3.75 ± 1.83 years; RAW n = 16, age 25 ± 2 years, RT experience 5.66 ± 3.00 years). Following two weeks of familiarization with the protocol , BP RT was carried out twice weekly. The EBD group completed more than half of their BP sets with elastic assistance and 10% higher training intensity than the RAW group. There was a significant time × group interaction in BW ( p = 0.008). Post hoc analysis showed a significant loss of 0.92 kg in the EBD group ( p = 0.049; effect size [ES] = −0.08; 95%CI [−1.80, 0.04]). A significant time effect for 1‑RM was observed ( p < 0.001). In both groups there was a significant change in 1‑RM of 5.00 kg ( p < 0.001; ES = 0.35; 95%CI [2.98, 7.02]). There was no significant change in any circumference or VAS measure. In conclusion, using an EBD leads to 1‑RM gains similar to conventional RAW BP training. However, more studies are required with highly trained individuals, in particular female athletes. Practitioners may implement EBD training for reasons of variation.

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Int J Environ Res Publ Health

The aim of this study was to compare the muscle activity between the sling shot assisted (SS) and control (CONT) flat barbell bench press for selected external loads of 70%, 85%, 100% one-repetition maximum (1RM). Ten resistance-trained men participated in the study (age = 22.2 ± 1.9 years, body mass = 88.7 ± 11.2 kg, body height = 179.5 ± 4.1, 1RM in the bench press = 127.25 ± 25.86 kg, and strength training experience = 6 ± 2.5 years). Evaluation of peak muscle activity of the dominant body side was carried out using surface electromyography (sEMG) recorded for the triceps brachii, pectoralis major, and anterior deltoid during each attempt. The three-way repeated measure ANOVA revealed statistically significant main interaction for condition x muscle group (p < 0.01; η 2 = 0.569); load x muscle group (p < 0.01; η 2 = 0.709); and condition x load (p < 0.01; η 2 = 0.418). A main effect was also observed for condition (p < 0.01; η 2 = 0.968); load (p < 0.01; η 2 = 0.976); and muscle group (p < 0.01; η 2 = 0.977). The post hoc analysis for the main effect of the condition indicated statistically significant decrease in %MVIC for the SS compared to CONT condition (74.9 vs. 88.9%MVIC; p < 0.01; ES = 0.39). The results of this study showed that using the SS significantly affects the muscle activity pattern of the flat bench press and results in its acute decrease in comparison to an equal load under CONT conditions. The SS device may be an effective tool both in rehabilitation and strength training protocols by increasing stability with a reduction of muscular activity of the prime movers.

The ‘Sling Shot’ increased the maximum number of repetitions in the barbell bench press in men with different resistance training experience

Article

Full-text available

Jan 2020

Purpose The study examined if the elastic device named Sling Shot could increase the maximum number of repetitions (MNR) and diminish the mean repetition duration in men with different resistance training experience while performing the bench press exercise in multiple sets. Methods Overall, 22 men were grouped depending on their resistance training experience. The most experienced group (MEG; 11 men, 65.45 ± 26.27 months of training experience) and the less experienced group (LEG; 11 men, 3.09 ± 2.07 months of training experience) performed 3 sets at 80% of the 1-repetition maximum test as fast as possible, with 2-min rest, of the barbell bench press exercise with and without the Sling Shot. Two 3-way ANOVA tests, with α = 0.05, were used to compare the MNR and mean repetition duration in inter- and intra-group comparisons across the sets. Results The Sling Shot increased the MNR in the 2 groups throughout the 3 sets. The increase was 50.5%, 65.4%, and 43.8% in the MEG group and 120%, 68.4%, and 43.3% in the LEG group for the 1^st, 2^nd, and 3^rd sets, respectively. However, there was no difference in the MNR between groups when the Sling Shot was used. Additionally, both groups performed the repetitions with a shorter mean duration with the Sling Shot than without it. No difference was observed between the groups. Conclusions Regardless of training experience, the Sling Shot constitutes an alternative for increasing the MNR and decreasing the mean repetition duration in multiple sets.

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Shaw, MP, Andersen, V, Sæterbakken, AH, Paulsen, G, Samnøy, LE, and Solstad, TEJ. Contemporary training practices of Norwegian powerlifters. J Strength Cond Res XX(X): 000-000, 2020-The aim of this study was to explore the contemporary training practices of Norwegian powerlifters. One hundred twenty-four Norwegian powerlifters completed an electronic questionnaire that surveyed their current training practices with a focus on 2 areas: (a) training content and (b) training design and monitoring. One hundred seventeen respondents met the inclusion criteria, and the sample included World, European, and Norwegian champions. Where data were dichotomized, chi-square tests were used. The most frequently reported (58.1%) category of training was 5-6 times per week, with no statistically significant associations between levels of competitors (international vs. noninternational) (X(1) = 0.414, p = 0.52). The most frequently reported load used in training was 71-80% 1 repetition maximum. The majority of Norwegian (76.9%) powerlifters train with variable resistance, with those competing internationally more likely to use elastic bands (X(1) = 4.473, p = 0.034). 32.5% of respondents reported that they included weightlifting exercises in their training. Norwegian powerlifters' training differs from practices previously identified in the literature, with a higher prevalence of elastic resistance, particularly for those competing internationally, and a decreased use of weightlifting exercises at all levels. Norwegian powerlifters train frequently (5 or more times per week) and with submaximal loads.

Effects Of Slingshot With Relative Intensity On Repetitions To Failure, Myoelectric Activity, And Perception Of Effort During The Bench Press Exercise In Recreationally-Trained Men

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Full-text available

Jul 2024

The purpose of this study was to evaluate the effects of the slingshot (SS) with the relative intensity between two conditions (with SS and without SS) on repetitions to failure at 70%1RM (RF70%1RM), myoelectric activity (sEMG), and perception of effort (sRPE) during the bench press exercise in recreationally-trained men. Sixteen recreationally-trained men (31.7±7.1years, 173.2±6.0cm, 85.4±15.9kg) performed the 1RM test with SS (107.3 ± 23.7 kg) and without SS (102.1 ± 21.9 kg). Then, all subjects performed RF70%1RM in two experimental conditions: with (WSS) and without (WTSS) the slingshot device. sEMG of the pectoralis major (PM), anterior deltoid (AD), lateral head of triceps brachii (TL), and long head of triceps brachii (TLO) was measured during both experimental conditions. sRPE was measured after both experimental conditions. Two-way ANOVAs (2x4) were used to test differences between conditions (WSS and WTSS) and muscle groups (PM, AD, TL, TLO) for iEMG and peak RMS. A paired t-test was used to measure differences between RF70%1RM (WSS and WTSS) and sRPE. Statistical difference was observed between RF70%1RM (WSS > WTSS, p=0.015). Statistical difference was observed between conditions for PM (peak RMS: WTSS > WSS, p=0.05). Statistical differences were observed for PM (iEMG: WTSS > WSS, p=0.05) and TLO activation (iEMG: WTSS > WSS, p=0.044). In conclusion, the use of the SS device induced a greater number of repetitions to failure and less myoelectric activation for the pectoralis major and long head of the triceps brachii. The perception of effort was similar between experimental conditions.

A comparison of muscle activation and concomitant intermuscular coupling of antagonist muscles among bench presses with different instability degrees in untrained men

Article

Full-text available

Sep 2022

The aim of this study was to analyze and compare the muscle activation and concomitant intermuscular coupling of antagonist muscles among bench presses with different instability degrees. Twenty-nine untrained male college students performed bench press exercises at an intensity of 60% 1 RM on three conditions: small unstable bench press with Smith machine (SBP), medium unstable bench press of free weight (FWBP), and large unstable bench press with increased instability by suspending the load with elastic bands (IIBP). One-way repeated measures analysis of variance was used to compare integrated EMG activity values of the biceps brachii (BB), posterior deltoid (PD), long head of the triceps brachii (TB), anterior deltoid (AD), upper portion of the pectoralis major (PM) muscles, and phase synchronization index (PSI) of BB-TB and PD-AD antagonist muscle pairs. A higher integrated EMG of BB muscle was found during bench press with a more unstable condition. IIBP showed a higher integrated EMG of prime movers (TB, AD, and PM) and stabilizing of BB than SBP and FWBP. PSI between muscle pairs of BB-TB in the gamma frequency band was higher in SBP than the other bench presses with unstable conditions, which may be related to the optimal “internal model” for antagonist muscles during bench press exercise. Therefore, IIBP training may be an effective accessory exercise to maintain a higher level of muscle activation across primary and stabilizing muscles with a lighter load for untrained men, while SBP may be a suitable bench press exercise for untrained participants who have not developed the neuromuscular adaptations necessary for correct stabilization of the elbow joint.

Shoulder Kinematics and Symmetry at Different Load Intensities during Bench Press Exercise

Article

Full-text available

Oct 2021

This study aimed to analyze between-shoulder kinematics symmetry at different load intensities considering full range of movement (ROM), mean and maximum velocities (VMEAN, VMAX), and accelerations (AMEAN, AMAX) of shoulders during phases 2 (characterized by positive acceleration and negative velocity, eccentric) and 3 (characterized by positive acceleration and velocity, concentric) of bench press exercise (BP); as well as to compare unilateral kinematics variables between the different load intensity intervals. Twenty-seven participants were evaluated during phases 2 and 3 of BP at different load intervals: interval 1 (55–75% 1-repetition maximum: 1RM), interval 2 (75–85% 1RM) and interval 3 (85–100% 1RM). Kinematics variables were determined using the Xsens MVN Link System. Results showed that full ROM was higher in left than right shoulder at all intensities (p = 0.008–0.035). VMEAN, VMAX, AMEAN, and AMAX were different in both shoulders for interval 3 during phase 2 and were lower as load intensity increased in both shoulders (p = 0.001–0.029). During phase 3, only VMAX on interval 2 was different between shoulders. Moreover, VMEAN, VMAX, AMEAN, and AMAX were greater during interval 1 compared with the others in both shoulders (p = 0.001–0.029). Therefore, there exists a kinematics asymmetry between both shoulders during phases 2 and 3 of bench press, although the acceleration was similar during both phases at all load intensities. Moreover, kinematic parameters differ between loads of 55–75% RM compared to 75–100% RM loads.

A Comparison of Electromyographic Inter-Limb Asymmetry During a Standard Versus a Sling Shot Assisted Bench Press Exercise

Article

Full-text available

Sep 2022
J HUM KINET

The objective of this study was to compare peak surface electromyography (sEMG) activity of selected muscles along with inter-limb asymmetries between a control (CONT) and a Sling shot assisted (SS) bench press exercise. Ten resistance-trained males with at least three-year experience in resistance training (22.2 ± 1.9 years, 88.7 ± 11.2 kg, 179.5 ± 4.1 cm, bench press one-repetition maximum (1RM) = 127.25 ± 25.86 kg) performed the flat bench press exercise under two conditions at selected loads (85% and 100% of 1RM assessed without the SS). Peak sEMG amplitude of triceps brachii, pectoralis major, and anterior deltoid was recorded for the dominant and the non-dominant side of the body during each attempt. The comparison between the dominant and the non-dominant side was carried out using the limb symmetry index (LSI(%) = (2*(XR-XL)/(XR + XL))*100%) where XR = values of the right side and XL = values of the left side. There was a main effect of condition (p = 0.004; η2 = 0.64) and the load (p = 0.004; η2 = 0.63) for the triceps brachii LSI in parallel with a main effect of condition (p = 0.003; η2 = 0.42) for the anterior deltoid LSI. Post hoc analysis for the main effect of condition showed significant differences in the LSI between the CONT and SS conditions for the triceps brachii (p = 0.003; 1.10 vs.-8.78) as well as for the anterior deltoid muscles (p = 0.03; 12.91 vs. 9.23). The results indicate that the assistance of the Sling shot significantly affects the sEMG activity pattern on both the dominant and non-dominant sides of the body while influencing inter-limb asymmetries.

The Effects of Altering the Concentric/Eccentric Phase Times on EMG Response, Lactate Accumulation and Work Completed When Training to Failure

Article

Full-text available

Jul 2020

Acknowledgments: We would like to thank the CAPES Brazil, FAPEMIG and the PRPq from the Federal University of Minas Gerais-Brazil. Abstract This study compared the electromyographic response, the blood lactate concentration (BLC), and the maximum number of repetitions (MNR) between protocols of different concentric/eccentric duration taken to muscle failure. This comparison may help to understand how different concentric/eccentric duration may influence performance and the central and metabolic responses in trained men. Seventeen strength-trained men performed two protocols in a counterbalanced design. Three sets of the Smith bench press exercise were performed to failure at 60% of the one-repetition maximum (1RM) using each protocol (4-s concentric/2-s eccentric [4 s: 2 s]; and 2-s concentric/4-s eccentric [2 s: 4 s]). The normalized root mean square (EMGRMS) and the mean frequency (EMGMF) of the electromyographic signals for the pectoralis major and the triceps brachii were compared in the first, middle, and last repetitions. The BLC was assessed at rest, during and after the test sessions. To compare the EMG and BLC, a 3-way ANOVA with repeated measures with a post hoc Tukey's test was used. To compare the MNR performed across the sets, an ANOVA-type rank test with the Dunn's post hoc test was used. The ANOVA indicated a greater EMGRMS for Protocol 4 s: 2 s in the pectoralis major and a lower EMGMF for Protocol 4 s: 2 s in the triceps brachii at the middle and last repetitions. Both protocols increased the EMGRMS and decreased the EMGMF across repetitions. Despite the results show different levels of activation and neuromuscular fatigue between protocols, the BLC and the MNR were similar.

Practical applications of biomechanical principles in resistance training: The use of bands and chains

Article

Full-text available

Jan 2014

In recent years, it has become popular for athletes and recreational trainers to perform resistance training with the addition of bands and chains. In this paper, we consider the advantages of manipulating an exercise to match the resistance provided with the force capabilities of the lifter, which generally change throughout the movement. We explain that bands and chains can be used to manipulate a variety of exercises that have the potential to enhance performance in sport and in many daily tasks. Whilst there are many similarities between the use of bands and chains for resistance training, we note that there are key differences and discuss the biomechanics of each material separately. In particular, we discuss that chains provide resistance primarily in the vertical plane and the resistance is linearly related to the displacement of the barbell. In contrast, bands can be set up to produce substantial horizontal forces in addition to the primary resistance force that often acts in the vertical direction. Also, research has demonstrated that bands provide a resistance force that is related in a curvilinear fashion to the displacement of the barbell. After introducing the main biomechanical features associated with each type of resistance material, we present findings from the strength and conditioning literature that has demonstrated the potential for bands and chains to improve the stimulus associated with strength and power training. At present, a more compelling evidence base has emerged for the use of bands in resistance training, particularly with regard to the development of power. It is not known whether this asymmetry reflects the greater number of studies conducted with bands or is influenced by methodological differences between studies. However, we also discuss the possibility that different inertial properties of bands compared with chains may make the former a more effective choice for the development of power. We hope that exercise professionals will benefit from this knowledge and obtain insight into how an understanding of biomechanical principles can assist with prescribing contemporary training regimes.

Effects Of Variable Resistance Training On Maximal Strength: A Meta-Analysis

Article

Full-text available

May 2015
J STRENGTH COND RES

Variable resistance training (VRT) methods improve the rate of force development (RFD), coordination between antagonist and synergist muscles, the recruitment of motor units, and reduce the drop in force produced in the sticking region. However, the beneficial effects of long-term VRT on maximal strength both in athletes and untrained individuals have been much disputed. The purpose of this study was to compare in a meta-analysis the effects of a long-term (>= 7 weeks) VRT program using chains or elastic bands and a similar constant resistance program in both trained adults practicing different sports and untrained individuals. Intervention effect sizes were compared among investigations meeting our selection and inclusion criteria using a random effects model. The published studies considered were those addressing VRT effects on the one repetition maximum (1RM). Seven studies involving 235 subjects fulfilled the selection and inclusion criteria. VRT led to a significantly greater mean strength gain (weighted mean difference: 5.03 kg; 95% CI: 2.26-7.80 kg; Z = 3.55; P < 0.001) than the gain recorded in response to conventional weight training. Long-term VRT training using chains or elastic bands attached to the barbell emerged as an effective evidence-based method of improving maximal strength both in athletes with different sports backgrounds and untrained subjects.

The relationship between the selected percentages of one repetition maximum and the number of repetitions in trained and untrained males

Article

Full-text available

Jan 2011

The purpose of this study was to determine the relationship between percentages (75; 85 and95%) of one repetition maximum (1RM) and number of repetitions during back squat; benchpress; and arm curl; especially using free weight in trained and untrained males. Nine trained(T) and 9 untrained (UT) males participated in this study. Subjects performed one set to failureat 75; 85; and 95% of 1RM; after determined the 1RM. Data were analyzed using two- wayanalysis of variance with repeated measures. There was significant difference (p < 0.05)between T and UT at 85% of 1RM at arm curl. Both groups performed significantly (p < 0.05)more repetitions during 75% of 1RM than 85 and 95% of 1RM (75 > 85 > 95%). The rating ofperceived exertion (RPE) was greater (p < 0.05) for high intensity than moderate intensity. Inconclusion; the number of repetitions is dependent to amount of muscle mass and exerciseintensity.

Effect of compensatory acceleration training in combination with accommodating resistance on upper body strength in collegiate athletes

Article

Full-text available

Aug 2014

Margaret T. Jones

Purpose To determine the impact of inclusion of a band or chain compensatory acceleration training (CAT), in a 5-week training phase, on maximal upper body strength during a 14-week off-season strength and conditioning program for collegiate male athletes. Patients and methods Twenty-four National Collegiate Athletic Association (NCAA) collegiate baseball players, who were familiar with the current strength and conditioning program and had a minimum of 1 year of formal collegiate strength and conditioning experience, participated in this off-season training study. None of the men had participated in CAT before. Subjects were matched following a maximal effort (1-repetition maximum [1-RM]) bench press test in week 1, then were randomly assigned into a band-based CAT group or a chain-based CAT group and participated in a 5-week training phase that included bench pressing twice per week. Upper body strength was measured by 1-RM bench press again at week 6. A 2 × 2 mixed factorial (method × time) analysis of variance was calculated to compare differences across groups. The alpha level was set at P<0.05. Results No difference (F1,22=0.04, P=0.84) existed between the band-based CAT and chain-based CAT groups. A significant difference was observed between pre- and posttests of 1-RM bench (F1,22=88.46, P=0.001). Conclusion A 5-week band CAT or chain CAT training program used in conjunction with an off-season strength and conditioning program can increase maximal upper body strength in collegiate baseball athletes. Using band CAT and/or chain CAT as a training modality in the off-season will vary the training stimulus from the traditional and likely help to maintain the athlete’s interest.

Time course for arm and chest muscle thickness changes following bench press training

Article

Full-text available

Dec 2012

The purpose of this study was to investigate the time course of hypertrophic adaptations in both the upper arm and trunk muscles following high-intensity bench press training. Seven previously untrained young men (aged 25 ± 3 years) performed free-weight bench press training 3 days (Monday, Wednesday and Friday) per week for 24 weeks. Training intensity and volume were set at 75% of one repetition maximum (1-RM) and 30 repetitions (3 sets of 10 repetitions, with 2-3 min of rest between sets), respectively. Muscle thickness (MTH) was measured using B-mode ultrasound at three sites: the biceps and triceps brachii and the pectoralis major. Measurements were taken a week prior to the start of training, before the training session on every Monday and 3 days after the final training session. Pairwise comparisons from baseline revealed that pectoralis major MTH significantly increased after week-1 (p = 0.002), triceps MTH increased after week-5 (p = 0.001) and 1-RM strength increased after week-3 (p = 0.001) while no changes were observed in the biceps MTH from baseline. Significant muscle hypertrophy was observed earlier in the chest compared to that of the triceps. Our results indicate that the time course of the muscle hypertrophic response differs between the upper arm and chest.

The Influence of Upper-Body Strength on Flat-Water Sprint Kayak Performance in Elite Athletes

Article

Full-text available

Nov 2013

Dry-land strength training is a fundamental component for elite kayak performance. The aims of this research were three-fold; firstly, to determine the relationship between performance time and strength scores for elite kayakers. Secondly, to identify how strength changes (gains or losses) over three training years relate with changes in performance time for elite kayakers. Thirdly, to compare the progression in performance times for elite athletes with the top three performers from the national championships. The performance data for 15 elite male kayakers and 10 elite females was collected over a two year timeframe. This group was reduced to nine males and eight females in the third and final year. There were direct and significant correlations between strength scores and performance times across a three year period. Bench-Press 1RM increased by 34.8% for males and 42.3% for females. Over the three seasons, the mean 1000-m time decreased by approximately 4.8%, 500-m times decreased by 7.3% (females), and 200-m times reduced 9.1%. The women K1 500-m moved from 11.9% difference to medallist to within 1.1%, during the 3 years. During the three years of this study a change in 1RM Bench-Press of 13% for males and 6.5% in females coincided with a change in performance times of 1%. For 1RM Pull-Up a change of 10% in males and 2.3% in females coincided with a change in performance times of 1%.

Effect of electrode position on EMG recording in pectoralis major

Article

Full-text available

Mar 2007

Despite the relatively long history of electromyography (EMG) application in a wide variety of disciplines, there are still discrepancies on a preferred position of EMG electrodes. The aim of this study was to determine an optimal position of bipolar surface electrodes for muscle pectoralis major. The recording was done during an isometric (static) effort of pressing the barbell from a lying position. The muscle activity was compared in 9 cases (3 positions of electrodes setting for 3 muscle compartments), recorded at a 1.6 s interval. The highest averaged value of integrated EMG for external, central and medial placement of electrodes, independent from the muscle (clavicularis, sternocostalis and abdominalis), was observed in the latter case of electrode positioning.

A Comparison of Muscle Activity Between a Free Weight and Machine Bench Press

Article

Jan 1994

Predictors of performance in elite discus throwers

Article

Jan 2002

T.D. Fahey

This study described the characteristics of 13 elite discus throwers and explored factors that predicted performance. The sample included three former world record holders and four Olympians- all of whom won Olympic medals during their athletic careers. The season best throws at the time these measurements were made ranged from 58.12 to 68.73 m. Best performances were recorded for the bench press (187.9±5.7 kg), dead lift (260.7±33.6 kg), squat (246.5±45.6 kg), power clean (150.7±23.7 kg), clean and jerk (143.0±19.8 kg), push press (133.4±27.0 kg), incline press (145.7±23.7 kg), snatch (107.6±11.1 kg), season best discus throw (63.7±3.4 m). 50 yard dash (45.72 m; 5.98±0.13 s), standing long jump (2.86±0.14 m), standing discus throw (53.0±3.1 m), and training camp discus throw (57.9±4.2 m) (mean ±SD). Moderate but significant correlations were revealed between season best throw and bench press (r=0.61) and dead lift (r=0.55; P<0.05). Step-wise multiple regression analysis showed that bench press best predicted season best performance in the discus (Discus throw (m)=0.13 bench press (kg)+40.34). These observations reaffirm the importance of the principle of specificity in motor performance.

Practical Guidelines and Considerations for the Use of Elastic Bands in Strength and Conditioning

Article

Oct 2014

ELASTIC BANDS ARE A FORM OF VARIABLE RESISTANCE AND A STRENGTH TRAINING MODALITY COMMONLY SEEN WITHIN A STRENGTH AND CONDITIONING TRAINING ENVIRONMENT. THEY ARE CONSIDERED AN EFFECTIVE TRAINING TOOL DUE TO THE FACT THAT THE RESISTANCE ALIGNS WITH THE FORCE CAPABILITY OF THE MUSCULATURE THROUGHOUT THE RANGE OF MOTION OF MANY MOVEMENT TASKS. THIS ARTICLE WILL EXPLORE THE WAYS IN WHICH ELASTIC BANDS CAN BE USED TO CHALLENGE OR ACCOMMODATE A MOVEMENT'S RANGE OF MOTION TO PROVIDE A MORE SPECIFIC STRENGTH-TRAINING STIMULUS. FOR A VIDEO ABSTRACT OF THIS ARTICLE, SEE SUPPLEMENTAL DIGITAL CONTENT 1 (SEE VIDEO, HTTP://LINKS.LWW.COM/SCJ/A146).