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THE INFLUENCE OF HAND GUARDS ON EXPLOSIVE 
FORCE AND PAIN AND EXERTION PERCEPTION IN A 
HANG HOLDING TASK 
 
Jorge Luiz Novaes Santos Júnior
1
, Rívia da Silva Passos
5,6
, Alinne Alves 
Oliveira
5,6
, Jonas R. Dias da Silva
5,6
, Ramon Silva Souza
1
, Rafael da Silva 
Passos
1
’
5,6
, Marco Machado
2,3
, Alexander J. Koch
4
, Rafael Pereira
5,6 
 
 
1
Arena Sparta, Sports and Research Development Center, Bahia, Brazil; 
2
Laboratory of Physiology and Biokinetic, UNIG Campus V, Itaperuna, Brazil; 
3
Laboratory of Human Movement Studies, Universitary Foundation of Itaperuna, Brazil; 
4
Exercise Physiology Laboratory, Lenoir-Rhyne University, Hickory, USA; 
5
Research Group in Neuromuscular Physiology, Department of Biological Sciences, 
Universidade Estadual do Sudoeste da Bahia, Brazil; 
6
Integrative Physiology Research Center, Department of Biological Sciences, Universidade 
Estadual do Sudoeste da Bahia, Brazil. 
 
Original article 
Abstract 
We investigated whether hand guards (HG) influence the perception of pain and exertion 
during the execution of a standardized task on high bar to induce forearm muscle fatigue as 
well as a decline in grip strength after the task. Design: A cross-over study design was 
employed 15 healthy and physically active volunteers completed static bodyweight holds (8 
cycles of 20 second load in hang and 10 second rest), on a high bar. The exercise protocol 
was performed with and without HG. Perception of pain and exertion during the task were 
recorded. Peak handgrip force and explosive force parameters (i.e., rate of force development 
[RFD] and contractile impulse [CI] at 30 to 200 ms) were obtained from force-time curves. 
Peak force and explosive force parameters were normalized (i.e., POS/PRE) for statistical 
analysis. The use of a HG significantly attenuates pain perception (p < 0.05), with a 
moderate to large effect size (d = 0.52), but did not alter the perception of exertion during the 
task, nor did it alter peak force, RFD, or CI. The use of HG reduces the perception of local 
pain during static holds. However, HG do not alter the perception of exertion during the task 
nor do they alter the gripping force ability immediately afterwards. This research did not 
receive any specific grant from funding agencies in the public, commercial, or not-for-profit 
sectors. 
 
Keywords: mixed modality training, hand guards, rate of force development, safety, 
gymnastics.
 
 
INTRODUCTION 
 
High-intensity functional training 
(HIFT) programs, which comprise the 
basis of world-renowned programs such as 
Crossfit™, among others (Neto &  
 
 
 
 
Kennedy, 2019), have been growing in 
popularity and recruiting adherents from 
diverse age ranges (children, youth and the 
elderly). These training programs use 

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weightlifting (e.g., clean, jerk, snatch) and 
gymnastic movements (e.g., pull up, ring 
muscle up, bar muscle up, handstand push 
up, handstand walking) and as such justify 
the recent use of the term “mixed modality 
training” (MMT) (Figueiredo, Pereira, & 
Neto, 2018; Marchini, Pereira, Pedroso, 
Christou, & Neto, 2017) to designate this 
training methodology. 
Generally, this training method aims 
to develop a set of muscle strength and 
endurance, cardiorespiratory conditioning 
and motor skills (Brisebois, Rigby, & 
Nichols, 2018; Maté-Muñoz, Lougedo, 
Barba, García-Fernández, Garnacho-
Castaño & Domínguez, 2017), obtained 
with workouts that involve one or more of 
the previously mentioned movements and 
seeking to perform as many repetitions as 
possible in a given time interval (i.e., As 
Many Rounds-Reps As Possible 
(AMRAP)), or every minute (i.e., Every 
Minute One Minute (EMOM)), or even 
performing a certain number of repetitions 
as quickly as possible (also called “for 
time workouts” or “time-limited physical 
workouts”). Thus, MMT training involves 
a constant quest for performance 
improvement. 
The culture of challenging oneself to 
improve partly explains the popularity of 
this training method, since it arouses great 
motivation.  However, as with any high-
intensity physical activity, excessive 
workloads can endanger the practitioners’ 
physical safety. In this context, as in any 
other sport, protective equipment is widely 
recommended and used (Church, Allen, & 
Allen, 2016; Colado & Garcia-Massó, 
2009; Kulund, Dewey, Brubaker, & 
Roberts, 1978), including lifting belts 
(Renfro & Ebben, 2006), knee-pads or 
knee wraps (Baltaci, Aktas, Camci, Oksuz, 
Yildiz & Kalaycioglu, 2011), weightlifting 
shoes (Sato, Fortenbaugh, & Hydock, 
2012), and hand guards for gymnastic bar 
exercises (Wettstone, 1941). 
Though proposed as a safety measure, 
a possible positive effect of wearing 
“protective equipment” on physical 
performance cannot be neglected.  For 
instance, wearing knee wraps has been 
found to directly increase squatting 
strength through the spring effect (Lake, 
Carden, & Shorter, 2012).  This raises 
debates about the legality of their use for 
competitive purposes. In the gymnastics 
field, hand protection could be ensured by 
magnesium (Pušnik & Čuk, 2014) and/or 
equipment commonly referred to as hand 
guards (HG) as safety equipment for bar 
exercises (Neal, Kippers, Plooy, & 
Forwood, 1995; Wettstone, 1941; Eckers, 
Fischer & Tscholl, 2020). 
Wettstone describes the great 
importance of HG during periods of 
practice as it protects against the 
development of blisters, allowing the 
gymnast to have a longer period of practice 
(Wettstone, 1941). This description makes 
clear the protective purpose of this 
equipment. Additionally, Neal et al. (1995)
 
studied the influence of the use of different 
types of HG on hand and wrist tension 
forces and the electromyographic (EMG) 
activity of the wrist and fingers flexor and 
extensor muscles during 3 giant swings on 
the high bar. The authors demonstrated 
that the use of this equipment increases 
wrist tension and bar forces, but did not 
observe any difference in EMG activity, 
indicating that the use of this equipment 
does not change the demand of the muscles 
involved in the body support during the 
studied gymnastic exercise. It is important 
to note that the movement studied (i.e., 
giant swings) is applied to artistic 
gymnastics, but is not typically practiced 
in HIFT programs. 
In the context of HIFT, the use of HG, 
in addition to the safety aspect, may 
involve an aspect of “advantage” by 
allowing athletes to perform a greater 
volume of gymnastic movements, such as 
pull ups, kipping pull up, chest-to-bar, 
toes-to-bar and bar muscle ups, which may 
be related to two aspects: 1) minimize skin 
friction with the bar, thereby reducing 
local pain and blistering, and/or 2) 
mechanically favour the performance of 

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the movements, reducing the demand of 
the forearm muscles. It is important to note 
that in many typical HIFT workouts, 
gymnastic exercises are succeeded by 
exercises that require strength and 
endurance of forearm flexors and 
extensors, such as deadlift, clean and 
snatch exercises, so that the performance 
in subsequent tasks can be optimized if the 
use of hand guards minimizes the effort of 
the aforementioned muscles, allowing a 
smaller decline in the capacity to produce 
force after gymnastic exercises. 
Thus, the present study aimed to 
investigate whether the use of HG 
influences the perception of pain and 
exertion during the execution of a 
standardized task on high bar to induce 
forearm muscle fatigue as well as the 
decline in force after the task. Our 
hypothesis is that HG can minimize the 
perception of pain in hands, while not 
reducing the exertion from the forearm 
muscles. 
 
METHODS 
 
In this cross-over study design, 15 
healthy and physically active volunteers (9 
men / 6 women; 26.0 ± 3.9 years, 70.0 ± 
10.0 kg, 170.1 ± 6.4 cm) were submitted to 
the same protocol to support their own 
body weight in hang on two non-
consecutive days (1 week apart). All 
volunteers were regular HIFT practitioners 
and had prior experience with gymnastic 
exercises, such as pull ups (at least 6 
months of training experience).  
Before starting the study, the 
volunteers were informed about the study 
procedures and signed an informed consent 
form, which was evaluated and approved 
by the local (Universidade Estadual do 
Sudoeste da Bahia) Research Ethics 
Committee. Additionally, volunteers were 
instructed to avoid the practice of exercises 
in the 24 hours preceding each 
experimental session. 
In order to induce fatigue of the 
forearm flexor and extensor muscles, all 
volunteers underwent a protocol to support 
their own body weight from a high bar 
(diameter = 2,8 cm). The protocol 
consisted of 8 cycles of 20 seconds load in 
hang and 10 seconds rest, totaling 160 
seconds sustaining their own body weight. 
This choice of testing with a static hold 
was used to ensure reproducibility of the 
session volume, as performing pull ups 
could lead to great variability in the degree 
of exercise-induced fatigue due to the 
technical level of each volunteer. Figure 1 
presents the experimental design. 
The same procedure was performed 
twice, one week apart, so that on each day 
volunteers performed the protocol in one 
of the two conditions: 1) with “hand 
guard”, or 2) without “hand guard”, and 
the order of these conditions was 
randomized. For this study we used a 
Skyhill
®
 hand guard (Florianópolis, SC, 
Brazil) developed to practice gymnastic 
exercises applied to HIFT (Figure 2). 
During the task execution, the use of 
magnesium was allowed, since its 
protective effect on the hands has been 
demonstrated by Pušnik & Čuk (2014). 
Prior to and immediately after the 
exercise protocol used to induce fatigue of 
the forearm flexor and extensor muscles, 
maximal voluntary handgrip isometric 
contractions (MVIC) and the perception of 
pain and exertion were recorded. 
Prior to the exercise protocol, 
volunteers were familiarized with the pain 
perception scale, which consists of a 100 
mm line representing "no pain" at the left 
limit (0 mm) and "very, very painful" at 
the right limit (100 mm), as used by 
Borges, Cerqueira, Rocha, Conrado, 
Machado, Pereira & Neto (2014). In the 
present study, the volunteers were 
instructed to consider the perception of 
hand and wrist pain to indicate the level of 
pain on the line. Volunteers were also 
asked if pain perception was located in the 
hand (palm), wrist or both regions. 
Similarly, volunteers were previously 
instructed regarding the assessment of 
perception of exertion from the forearm 

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muscles during the task. The Borg CR10 
effort perception scale was used to assess 
the perception of exertion during the task, 
as used by McGorry, Lin, Dempsey, & 
Casey (2010). 
The volunteers underwent 4 maximal 
voluntary handgrip isometric contractions 
(MVIC) (two with each hand) with a strain 
gauge-based force transducer (EMG 
System, São José dos Campos, SP, Brazil). 
To perform the MVIC, the volunteers 
stood in an orthostatic position, and were 
instructed to position the arm at 90° of 
elbow flexion with their forearm in the 
neutral position. The device’s handle was 
fit into their palm with the fingers at 90° 
flexion at the proximal and distal 
interphalangeal joints with the thumb in 
90° abduction. Two handgrip maximal 
isometric force attempts with an inter-
attempt rest interval of 30 seconds were 
performed for each arm (right and left), 
and the maximum handgrip force of each 
trial was identified. The order of tested 
hand (i.e., right and left) was random. 
Subjects were carefully instructed to 
contract “as fast and forcefully as possible” 
after the command “go,” sustaining the 
contraction for 3 seconds when the 
command “stop” was given. Verbal 
encouragement was given by the evaluator 
during the maintenance of the MVIC and 
the best attempt at each moment (i.e., 
before and immediately after the fatigue 
protocol) was used for analysis purposes. 
The sampling rate from force transducer 
was set at 2 kHz, as performed by 
Schettino, Luz, Oliveira, Assunção, 
Coqueiro, Fernandes, Brown, Machado & 
Pereira (2014) and  Borges, Fernandes, 
Schettino, Coqueiro & Pereira (2015). 
The force-time curves were analyzed 
to obtain the rate force development (RFD) 
in the first 200 milliseconds of MVIC. 
Briefly, the force-time curves were 
smoothed by a digital fourth-order, zero-
lag Butterworth filter, with a cutoff 
frequency of 15 Hz, as proposed by 
Aagaard, Simonsen, Andersen, Magnusson 
& Dyhre-Poulsen (2002). The Δ force / Δ 
time ratio was measured at time intervals 
of 30, 50, 100, 150 and 200 ms after the 
onset of MVIC. Likewise, the area under 
the force-time curve was calculated at the 
same time intervals as mentioned above, 
obtaining the contractile impulse (CI) 
parameter (Aagaard et al., 2002). Both CI 
and RFD measure explosive force, 
however, they use distinct but 
complementary methods. The CI measures 
accumulated area under the force–time 
curve which reflects the entire time period 
of contraction, including the overall 
influence of the various time-related RFD 
parameters (Aagaard et al., 2002; Schettino 
et al., 2014). 
The onset of muscle contraction was 
defined as the time point at which the force 
curve exceeded the baseline by 2.5% of the 
difference between baseline force and the 
maximum voluntary contraction (i.e., 
maximum handgrip force), as proposed by 
Aagaard et al. (2002) and Schettino et al. 
(2014). All analyses were conducted using 
specific algorithms developed in 
MATLAB
®
. 
For descriptive purposes, the 
explosive force data (i.e., RFD and CI) 
obtained immediately after the fatigue 
protocol were normalized by the 
measurements obtained before the fatigue 
protocol (Δ (%) = [POS / PRE] * 100) for 
each arm (i.e., right and left). For statistical 
analysis, Δ POS / PRE from the right and 
left arm were grouped, so that comparisons 
between the experimental conditions with 
and without hand guard were made 
considering the mean ΔPOS / PRE (%) 
from the right and left arms. Figure 3 
illustrates the data analysis and grouping 
procedure for statistical analysis. 
Student's t-test was used to compare 
pain and effort perception in the task 
performed with and without hand guard. 
Similarly, ΔRFD and ΔCI from each 
experimental condition (i.e., with and 
without HG) were compared with Student's 
t-test. For all comparisons, the significance 
level of p ≤ 0.05 was used, and all 
statistical analyses were performed using 

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SPSS 21.0 software (IBM Corp., Chicago, 
IL, USA). The effect size was calculated to 
obtain Cohen's d-index as proposed by 
Cohen (1988). The following interpretation 
was considered: small (d = 0.2), medium 
(d = 0.5), and large effect size ( d = 0.8). 
D a t a a r e p r e s e n t e d a s m e a n ± s t a n d a r d 
deviation. 
 
 
 
 
 
 
 
Figure 1. Experimental design. 
 
 
 
 
 
 
Figure 2. “Hand guard” used, and its proper use mode. 
 
 
 
 
 
 
 
 

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Figure 3. Force / time curves of the right (A) and left (B) arms, before (PRE) and after (POS) 
the task for fatigue induction without and with hand guard (HG). Peak Force (PF), rate of 
force development at 30 (RFD 30ms) and 200 ms (RFD 200ms), Contractile Impulse at 30 
(CI 30ms) and 200 ms (CI 200ms) values are presented in absolute and normalized values 
(POS / PRE). The central column shows the mean of the right and left arms in studied 
conditions (i.e., without and with HG). 
 
 
 
Table 1  
Perception of pain and exertion during the proposed task without and with hand guard. 
 
 
Without 
HG 
With HG 
P 
value
Mean difference 
[95% Conf. Int.] 
Effect 
size 
Perception of Pain 
(mm) 
5.5±0.5 4.1±0.6 0.038* 1.40 [0.09 to 2.71] 0.52 
Perception of 
exertion (A.U.) 
7.5±0.5 7.1±0.5 0.290 0.46 [-0.44 to 1.38] 0.28 
 
 
 
 
 
 
 
 

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Table 2  
Mean ± standard deviation from the difference ( Δ POS / PRE (%)) of the peak force and the 
right and left arms explosive force parameters under experimental conditions with and 
without hand guard (HG). P values, mean difference and effect size of comparisons between 
experimental conditions are also presented. 
 
 Without HG With HG
P value 
Mean difference 
[95% Conf. Int.] 
Effect 
size  R i g h t L e f t Mean D E Mean
Peak Force 88.8±16.6 86.6±16.5 87.7±14.8 86.9±22.0 80.3±19.1 83.6±18.8 0.520 4.1 [-9.2 to 17.4] 0.17
RFD 
200ms 
75.5±19.5 71.6±17.8 73.5±17.0 68.2±22.0 62.1±18.1 65.2±19.2 0.163 8.4 [-3.8 to 20.5] 0.37 
RFD 
150ms 
74.8±20.1 70.2±19.4 72.5±18.0 67.9±26.6 59.1±19.9 63.5±22.0 0.197 9.0 [-5. 3 to 23.3] 0.34 
RFD 
100ms 
76.1±23.0 70.0±21.7 73.0±20.4 69.2±33.2 58.3±22.5 63.8±26.0 0.270 9.3 [-8.0 to 26.6] 0.29 
RFD 50ms 79.0±27.6 73.6±26.1 76.3±24.5 71.0±35.5 60.9±26.3 66.0±28.6 0.281 10.3 [-9.4 to 30.1] 0.29
RFD 30ms 80.7±29.1 75.5±28.1 78.1±26.1 71.9±34.7 63.8±29.1 67.8±29.5 0.299 10.3 [-10.2 to 30.7] 0.28
CI 200ms 75.7±21.2 70.4±19.6 73.0±18.7 68.1±27.1 59.6±20.3 63.9±22.3 0.194 9.2 [-5.2 to 23.6] 0.34
CI 150ms 76.3±22.7 70.4±21.3 73.3±20.1 68.9±31.2 58.9±22.0 63.9±24.9 0.238 9.4 [-7.0 to 25.8] 0.31
CI 100ms 77.8±25.4 71.7±23.9 74.8±22.6 70.2±34.4 59.8±24.3 65.0±27.3 0.275 9.8 [-8.7 to 28.2] 0.29
CI 50ms 80.2±28.6 74.9±27.4 77.5±25.5 71.5±34.6 63.2±28.1 67.4±29.0 0.295 10.2 [-9.9 to 30.2] 0.28
CI 30ms 81.3±29.6 76.6±28.5 79.0±26.5 72.5±34.1 65.5±30.8 69.0±30.0 0.314 10.0 [-10.5 to 30.5] 0.27
RFD = Rate of Force Development; CI = Contractile Impulse  
 
 
 
RESULTS 
 
All volunteers completed the proposed 
exercise protocol in both experimental 
sessions. Pain perception reported 
immediately after the experimental session 
was significantly lower in the experimental 
session with the use of hand guard (p < 
0.05), and the observed effect size was 
classified as medium to large (d = 0.52). 
All volunteers reported pain at the end of 
the task performed without a hand guard. 
From 15 volunteers, 14 (93.3%) reported 
hand (palm) pain and only 1 (6.7%) 
reported wrist pain at the experimental 
session without HG. When the HG was 
used 6 volunteers (40%) did not report 
pain, 8 (53.3%) reported hand (palm) pain 
and only 1 (6.7%) reported wrist pain. 
The perception of exertion during the 
t a s k w a s n o t d i f f e r e n t b e t w e e n 
experimental sessions (p > 0.05). The 
results from perception of pain and 
exertion during the task are presented in 
table 1. 
The peak force and explosive force 
parameters decreased by about 13 to 37% 
after the induced fatigue by the used hang 
holding task (see table 2). The peak force 
and the explosive force parameters decline 
did not differ significantly between 
experimental conditions with and without 
hand guard (p > 0.05), as shown in table 2. 
 
DISCUSSION 
 
The present study aimed to investigate 
whether the use of HG influences the 
perception of pain and exertion during a 
standardized task to induce forearm 
muscles fatigue as well as a decline in peak 
force and explosive force after the applied 
task. Our results showed that the use of 
HG significantly attenuates pain 
perception, with a moderate to large effect 
size, but did not attenuate the perception of 
exertion during the task, as well as the 
ability to produce maximum force and 
explosive force immediately after the task. 
HG are proposed as protective 
equipment to perform gymnastic exercises 
on the bar (Neal et al., 1995; Wettstone, 
1941) and our results corroborate this 
proposal, since HG attenuated pain 
perception during a standardized task 
sustaining the body weight on  high bar. 
The compression and friction generated on 
the palm during this task generates pain 
and may therefore be a limiting factor for 
the practice of higher volumes of exercises 

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on high bar. Our results indicate that the 
use of HG may effectively enable a greater 
volume of training in the same session, 
even though factors other than pain may 
limit the session volume. 
Despite the lower pain perception in 
the palm and wrist, HG did not attenuate 
the perception of exertion during the task.  
This may be due to the fact that this model 
of HG does not attach to the bar (see figure 
1), requiring maintenance of the 
contraction of forearm and fingers flexor 
muscles to sustain the hold. McGorry et al. 
(2010) demonstrated that the measure of 
perceived exertion involving forearm 
muscles, as used in our study, has a direct 
relationship with the handgrip strength 
demand.  
Many HG models are used by 
gymnasts, with differing models suited to 
various gymnastic movements. In the 
present study we examined the model 
where the HG is fixed to the wrist but not 
fixed to the bar.  Our results indicate that 
the used HG model does reduce the 
demands of the forearm muscles. Previous 
research by Neal et al. (1995), compared 
the forces applied to the bar and the 
electromyographic activity (EMG) of the 
forearm muscles of gymnasts during the 
execution of 3 giant swings on the high bar 
with and without the use of HG (2 typical 
models – webbing loops and dowelled 
hand guards, used for gymnastics). EMG 
activity was equal during the performance 
of the movements under conditions with 
and without both HG models.  
Neal et al. (1995) submitted 10 
gymnasts to a movement typically used in 
artistic gymnastic competitions, which is 
not directly applicable to HIFT-based 
workouts.  Despite the differences in 
movement analyzed (giant swing vs. static 
support) and HG style, our results are in 
line with the cited study, leading us to infer 
that the used HG model in our study meets 
the criteria of hand protection, but does not 
alter muscular demand when sustaining the 
body on high bar, which was confirmed by 
the force measurements before and 
immediately after the proposed task. In 
fact, the ability to generate maximum force 
and explosive force were not different in 
studied experimental conditions (i.e., with 
and without HG).  
It is important to note that the 
explosive force analysis applied in our 
study permits the differentiation of 
influence of neural factors (i.e., the ability 
to recruit motor units and its recruitment 
pattern) and muscular factors (i.e., the 
contractile apparatus characteristic and 
availability of energy substrates), since the 
ability to increase force within the first 100 
ms of a MVIC is directly related to neural 
factors, while the ability to increase 
strength from 100 to 200 ms is directly 
related to muscle factors (Cerqueira, 
Pereira, de Mesquita, Rocha, & de Moura 
Filho, 2019; Maffiuletti, Aagaard, 
Blazevich, Folland, Tillin, & Duchateau, 
2016; Oliveira, Corvino, Caputo, Aagaard, 
& Denadai, 2016). 
Perception of palm pain has been 
found to directly influence the descending 
command pattern of the central nervous 
system to the muscles involved in the 
handgrip task (Tokimura, Di Lazzaro, 
Tokimura, Oliviero, Profice, Insola, 
Mazzone, Tonali, & Rothwell, 2000) and 
consequently in the ability to produce 
muscle force.  Despite this, the present 
results did not show any advantage in the 
use of HG in regards to force production, 
as there were no observed differences 
between conditions in the force 
measurements in the first 100 ms of the 
MVIC after the applied task. However, it is 
important to emphasize that we used a 
time-limited task, where all subjects were 
able to complete the task, regardless of the 
use of HG. Thus, we cannot infer whether 
the use of HG would enable one to sustain 
the task for a longer time period before the 
onset of fatigue.  The effect of HG on time 
to exhaustion during static holds could be 
investigated in future studies, since the 
current experimental design was directed 
to investigate the neural and mechanical 

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factors involving the use of HG during a 
time-limited task. 
The results of this study shed light on 
aspects related to the mechanisms involved 
in the use of HG in a time-limited task, 
while future studies should investigate how 
the use of HG influences the performance-
limited tasks (i.e., the maximum time 
sustaining the body weight or recording the 
maximum pull-ups, toes-to-bar or bar 
muscle ups repetitions), which would 
require good control of technical variables 
during the movement execution. 
The practical implications of these 
results may affect athletes and coaches in 
the area of HIFT or related modalities 
where gymnastic exercises, such as pull 
ups, toes-to-bar and bar muscle ups are 
applied. In this context, our results indicate 
that athletes and coaches should choose 
whether or not to use HG on the basis of 
pain perception rather than the possible 
mechanical advantage of using this 
accessory. Additionally, it is possible to 
hypothesize that in typical HIFT workouts, 
where weightlifting exercises (e.g., clean, 
snatch) can be performed immediately 
after gymnastic exercises on high bar, the 
use of HG would not favour a higher grip 
strength and would lend no advantages. 
 
CONCLUSION 
 
In conclusion, the results of this study 
suggest that the use of HG reduces the 
perception of local pain (palm). However, 
it does not provide any mechanical 
advantage for the applied task, since it 
does not reduce the perception of exertion 
during the task nor the ability to develop 
force based on neural and/or muscular 
aspects immediately after the proposed 
task. When deciding whether to use HG for 
HIFT-based workouts, athletes and 
coaches should be aware that this is 
protective equipment and there is no 
evidence that it offers any mechanical 
advantage. 
This research did not receive any 
specific grant from funding agencies in the 
public, commercial or not-for-profit 
sectors. 
 
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Andersen, J. L., Magnusson, P., & Dyhre-
Poulsen, P. (2002). Increased rate of force 
development and neural drive of human 
skeletal muscle following resistance 
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620150 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Corresponding author: 
 
Rafael Pereira 
Department of Biological Sciences, 
Universidade Estadual do Sudoeste da 
Bahia (UESB) 
Rua José Moreira Sobrinho, s/n, 
Jequiezinho / Jequie 45210-506, Bahia, 
Brazil.  
Email: rpfisiologia@gmail.com 
 
 
Article received: 7.4.2020 
Article accepted: 6.9.2020 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Junior J.L.N.S. et al.: THE INFLUENCE OF HAND GUARDS ON EXPLOSIVE FORCE …         Vol. 13 Issue 1: 107 - 117 
 
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