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The effects of two maximum grip strength training
methods using the same effort duration and different
edge depth on grip endurance in elite climbers
Eva López-Rivera a & Juan José González-Badillo b
a Club Vertical Toledo, Spain
b Faculty of Sport Sciences, University Pablo de Olavide, Seville, Spain
Version of record first published: 21 Aug 2012
To cite this article: Eva López-Rivera & Juan José González-Badillo (2012): The effects of two maximum grip strength
training methods using the same effort duration and different edge depth on grip endurance in elite climbers, Sports
Technology, DOI:10.1080/19346182.2012.716061
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RESEARCH ARTICLE
The effects of two maximum grip strength training methods using
the same effort duration and different edge depth on grip endurance
in elite climbers
EVA LO
´PEZ-RIVERA
1
& JUAN JOSE
´GONZA
´LEZ-BADILLO
2
1
Club Vertical Toledo, Spain and
2
Faculty of Sport Sciences, University Pablo de Olavide, Seville, Spain
(Received 5 January 2012; accepted 24 July 2012)
Abstract
Nine experienced rock climbers (mean climbing ability of 8a þ/b) were randomly assigned to Group A (n¼5) and Group B
(n¼4). Both groups trained dead hanging using two different methods. One method consisted of using the minimum edge
depth (MED) they could hold the weight of their body; the other consisted of using a bigger edge (18 mm) with maximum
added weight (MAW). Group A performed MED from Weeks 1 to 4, and then performed MAW the following 4 weeks(termed
as MED–MAW group); Group B performed MAW from Weeks 1 to 4 and then performed MED the following 4 weeks
(termed as MAW– MED group). Maximum grip strength and endurance tests were conducted initially (ST1; ET1), following
4 weeks (ST2; ET2), 8 weeks (ST3; ET3), 2 weeks (ST4; ET4) and 4 weeks (ST5; ET5) completion of training to determine
the effects of detraining. The 9.6% improvement in g rip strength ( p.0.05) in MAW–MED group in ST2 and 6.9% in ST4
was greater than in MED –MAW group. In terms of grip endurance, MAW –MED group in ET2 (16.69%) and in ET3
(19.95%) improved more than MED – MAW group ( p.0.05). Significant positive correlation was found between ST and
ET, and between changes in strength and changes in endurance at all stages, controlling for body weight in all cases. The
present data suggest that the most effective sequence of finger strength training methods is MAW– MED.
Keywords: rock climbing, finger strength training, finger endurance training, elite climbers, strength on endurance
Introduction
There are a number of studies that attempt to describe
the elite climber in discovering the determining factors
of performance in the sport of rock climbing. Some
authors suggest that the physical limits of the rock
climber are those of maximum finger strength (Grant,
Hynes, Whittaker & Aitchison, 1996; Guidi, 1994;
Lehner & Heyters, 1998; MacLeod, Sutherland,
Buntin, Whitaker, Aitchison, Bradley & Grant, 2007;
Watts & Jensen, 2003) and finger endurance (Cutts &
Bollen, 1993; Ferguson & Brown, 1997; Grant,
Shields, Fitzpatrick, Ming Loh, Whitaker, Watt &
Kay, 2003; Usaj, 1996, 2001). It has also been shown
that maximum strength training provokes improve-
ment in muscular endurance (Hennessy, Watson,
Orlando, Florida, Hickson, Dvorak, Gorostiaga,
Kurowski, & Foster, 1988; Hickson, Dvorak, Gor-
ostiaga, Kurowski, Foster, Hidaka & Foster (1988,
1994); Marcinik, Potts, Schlabach, Will, Dawson &
Hurley, 1991; Osteras, Helgerud & Hoff, 2002;
Paavolainen, Hakkinen, Hamalainen, Nummela &
Rusko, 1999; Stone & Coulter, 1994). Furthermore, a
correlation was found between the maximum volun-
tary contraction (MVC) of the hand and the time until
fatigue in a second contraction at 60% of MVC after an
incompletepause, according to Guidi (1994), as well as
between the MVC using the open crimp and the
performance level in the study by MacLeod et al.
(2007). All the above findings lead us to suggest that
training and increasing maximum grip strength can be
important for the improvement in maximum
grip endurance in rock climbing and also for an
increase in performance.
It has also been suggested that to produce this effect,
it is necessary for the strength training to be specific
(Anderson& Kearney, 1982;Bell, Snydmiller, Neary &
Quinney, 1989; Paavolainen et al. 1999; Tanaka,
Costill, Thomas, Fink & Widrick, 1993). We observe
that in the majority of studies, a dynamometer has been
used to measure or study hand endurance (Binney,
2002; Usaj, 2001; Quaine & Vigouroux, 2004;Quaine,
Vigouroux & Martin, 2003; Watts & Jensen, 2003),
which is questionable from a performance point of view
according to some authors (Scho¨ffl, Mo¨ckel, Ko¨ster-
meyer, Roloff & Ku
¨pper, 2005; Schweizer, Schneider
ISSN 1934-6182 print/ISSN 1934-6190 online q2012 Taylor & Francis
http://dx.doi.org/10.1080/19346182.2012.716061
*Correspondence: E. Lo
´pez-Rivera, Club Vertical, Toledo, Spain. E-mail: evalopriv@gmail.com
Sports Technology,
iFirst article, 2012, 1–11
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& Goehner, 2007; Watts, 2004) because applyingforce
on the dynamometer causes the second phalangeof the
fingers to flex against the palm of the hand, a gesture
which seldom occurs in climbing. Therefore, as also
other authors suggest (Grant et al. 1996; MacLeod
et al. 2007; Schweizer et al., 2007; Watts, Newbury &
Sulentic, 1996, Jensen, Watts, Lawrence, Moss &
Wagonsomer, 2005), it would be necessary to propose
the use of a specific device that could measure – and be
used for – finger strength and endurance training a
specific rock climbing movement technique.
An essential characteristic of climbing is hanging off
small edges or pockets, and at a high level we consider a
small grip edge to beof a depth less than half the size of
the distal phalange of the fingers (Quaine & Vigouroux,
2004; Schweizer & Hudek, 2011; Watts, 2004). The
usual way of gripping such a hold is the so-called
crimp grip, where the distal interphalangeal is hyper-
extended and proximal interphalangeal joints are
rather 80– 908flexion in half crimp position, against
.908in full crimp (Schweizer, 2001). These observa-
tions support the suggestion that in order to achieve
better climbing performance a grip strength method
can be used, allowing hanging off holdswith the least or
minimum edge depth (MED) as possible. On the other
hand, regarding improvements in strength, it has been
observed in a number of studies that training with extra
weight (maximum added weight, MAW) improves
strength (Behm, 1995; Hakkinen, Alen & Komi,
1985b, Hakkinen, Pakarinen, Kraemer, Hakkinen,
Valkeinen & Alen, 2001; Harris, Stone, O’Bryant,
Prolux & Johnson, 2000; Kraemer, Koziris, Ratamess,
Hakkinen, Triplett-McBride, Fry & Fleck, 2002; Siff &
Verkhoshansky, 1999). However, only a few scientific
articles address the topic of specific training to optimise
the rock climber’s performance (Koestermeyer &
Weineck, 1995; Schweizer et al. 2007), and it appears
that none of them have attempted to compare the
effectiveness of the two specific maximum finger
strength training regimes mentioned: using MED or
MAW in high-level climbers. Additional research is
needed to assess how specific climbing training impacts
on a climber’s performance (Watts, 2004).
Therefore, the aim of this research was to determine
the effects of two different strength training methods
in which either the edge depth or the added weight
is variable, carried out in a different order, over
grip endurance onan exercise specific of climbing, on a
group of elite climbers.
Methods
Various prerequisites were established for the
participants to take part in the study (Table I).
Each participant was individually informed in writing
about the characteristics, risks and drawbacks
associated with the study and was given a consent
form to sign. Participants who did not meet any of
the requirements were excluded.
The voluntary participants completed a question-
naire detailing their personal data, climbing grade
performance, defined as the most difficult redpoint
ascent achieved in the past 6 months (“redpoint”
means leading a sport route after inspecting it, and
often after practising individual moves), number of
years of training for climbing and age. Climbing
ability was converted to a standard numerical scale to
enable calculations and statistical analysis according
to Watts, Martin & Durtschi (1993) (Table II).
After the selection, 12 sport climbers (10 men and 2
women) voluntarily joined the study; 9 of them (8 men
and 1 woman) finished the programme. The descrip-
tive figures for each group are shown in Table III.
Apparatus
We designed and fabricated a specific apparatus that
consists of an edge made of wood whose depth can be
Table I. Requirements for the participants in the study.
†To be at least 25 years of age
†To have been climbing for at least 5 years
†Regular training practice for climbing, more than two days
a week during the past year
†Rock climbing level of 8a or more
†Experience with dead-hanging training on edges for more than
4 weeks
†Not having performed dead-hanging training in the previous
2 months
†Absence of finger or lower back injuries during the past year,
or any condition that makes it inadvisable to take part in a
training program
†Being able to commit themselves to a training and testing
schedule for 3 months
Table II. Standardized climbing ability conversion chart.
French scale Standard numerical scale
6a 1
6aþ1.25
6b 1.50
6bþ1.75
6c 2
6cþ2.25
7a 2.50
7aþ2.75
7b 3
7bþ3.25
7c 3.50
7cþ3.75
8a 4
8aþ4.25
8b 4.50
8bþ4.75
8c 5
8cþ5.25
9a 5.50
9aþ5.75
9b 6
Note: Reproduced from Watts et al. (1993).
Eva Lo
´pez-Rivera & J. J. Gonza
´lez-Badillo2
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adjusted with a precision gauge to measure finger
endurance and strength, and designed to train in a
specific way (dimensions 500 £250 £24 mm, man-
ufactured by Eva Lo
´pez & Dafnis Ferna
´ndez in 2004;
Creative Commons license; Figure 1). In addition,
two Casiowhand chronometers were used to measure
the hanging duration, a Petzlwharness to hang the
added weights and magnesium carbonate of the brand
Campwto reduce the effect of perspiration.
Design
During the first week (week 1) initial maximum
finger strength (ST) and finger endurance tests (ET)
were carried out. The tests were repeated (retests) in
the second week (week 2) to assess the reliability of
the measurements and served as initial tests (ST1
and ET1). The participants were sorted according to
their results in the retest and then assigned to one of
the two groups using the abba sorting: a participant
was randomly chosen and assigned to Group A and
the rest were assigned according to the bba pattern
until both groups were complete.
In Week 5, tests for maximum strength and
endurance (ST2 and ET2) were carried out and in
Week 10, ST3 and ET3 tests were carried out. To
assess the effects of detraining and after a rest week
from the training methods (week 11), ST4 and ET4
tests were performed in Week 12. The following week
the participants rested, and a week later (week 14) the
final tests were carried out (ST5 and ET5; Table IV).
Testing procedure
Before measurements, participants were informed
about the procedures and rules for the tests and were
instructed regarding the proper hanging technique in
the 2 weeks before the first test. Two days before the
test each participant performed a light training
session, having rested from training the day before
the test. Tests were carried out on Tuesdays, always at
the same time of day.
Before the test itself, a specific 15-min warm-up
was performed, consisting of neck, shoulder, arm and
finger flexing and extensions, and three progressive
sets of the test exercise with moderate intensity. The
participants were weighed and their heights were
recorded after a 5-min rest period. Then the test for
maximum strength with added weight was carried out,
and after a 10-min rest the endurance test was
performed.
During the weeks when the participants rested from
the proposed training in this study, they continued
with their individual training that was similar, at an
intensity specific to their performance level.
Strength test (ST). It consisted of half crimp grip
dead hanging with an edge depth of 15mm and the
Figure 1. Specific apparatus consisting of an adjustable edge depth.
The depth of the edge can be changed with the help of the screws
and measured with a calliper. (Dimensions 500 £250 £24 mm;
manufactured by Eva Lo
´pez & Dafnis Ferna
´ndez in 2004; Creative
Commons license).
Table IV. Training schedule.
Week 1 ST and ET (tests) Pre-test phase (test and
retest)
Week 2 ST1 and ET1 (retests) Training phase 1
Week 1 3 £10”:30A group: MED
Week 2 4 £10”:30B group: MAW
Week 3 5 £10”:30
Week 4 5 £10”:30
Week 5 ST2 and ET2 Test post-training phase 1
Week 6 3 £10”:30Training phase 2
Week 7 4 £10”:30Group A:MAW
Week 8 5 £10”:30Group B:MED
Week 9 5 £10”:30
Week 10 ST3 and ET3 Test post-training phase 2
Week 11 Rest from MAW and
MED: detraining
Week 12 ST4 and ET4
Week 13
Week 14 ST5 and ET5
ST ¼strength test; ET ¼endurance test; MED ¼training with
the minimum edge depth without added weight; MAW ¼Training
with maximum added weight on 18 mm edge.
Table III. Descriptive characteristics of the participants.
Group A
(n¼5)
Group B
(n¼4)
Mean ^sd Mean ^sd
Age (years) 32.20 ^4.32 28.25 ^2.06
Height (cm) 171.40 ^10.91 168.88 ^4.48
Initial body mass (kg) 63.68 ^11.98 68.95 ^4.87
Climbing experience (years) 15.80 ^4.60 11.25 ^2.22
Climbing grade performance
(standardized scale;
Watts et al., 1993)
4.30 ^0.57 4.19 ^0.75
Climbing grade performance ¼the most difficult redpoint ascent
achieved in the past 6 months (“redpoint” means leading a sport
route afterinspecting it,and often after practising individual moves).
The effects of two maximum grip strength training methods in elite climbers 3
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maximum load with which the participant could
maintain the grip for 5 s (Figure 2). The 15mm edge
depth (Figure 3) was considered to be the most
representative of the average size of holds used in
competitions, and to have a high significant
relationship with climbing grade. With this size as a
basis, a bigger depth (18 mm) was chosen for the
weekly training and a smaller one (11 mm; Figure 4) for
the endurance test, given that according to Bourne,
Halaki, Vanwanseele & Clarke, (2011), holding force
for very small holds (smaller than 5 mm) depends on
finger anatomy (soft tissue) rather than on muscular
strength.
After a warm-up, the strength test was performed.
An initial added weight was chosen so that the
participant could hold onto the edge for 15 –20s.
Progressive attempts were made with weight incre-
ments of 5– 10 kg according to the participants’
capacity with rest intervals of 5 min. The idea of the
increments was to keep the number of attempts
below five in order to reduce fatigue.
When the participant was no longer able to maintain
the half crimp for 5 s with all their fingers, either
flexing, lifting their arms or trunk or legs up, the test
was stopped and the last load withstood was recorded.
Endurance test (ET). It consisted of half crimp dead
hanging on an edge with a depth of 11 mm for the
maximum possible duration without additional weight
(Figure 5). The test ended once the contact was lost
between the participant and the edge or at the point
where arms were flexed or where legs or trunk were
elevated, and this was the moment when maximum
duration attained by the participant was recorded.
Training
Test and training sessions were always performed at
the same time of day, and the participants were told
not to change their daily habits for the length of the
study. These methods were not intended to
substitute conventional climbing training but rather
to serve as an additional resource for strength
training. Afterwards, the other technical and physical
training for that session was carried out.
Both methods of maximum finger strength training
compared in this study shared apparatus, intensity
and training volume: dead hanging exercises with the
half crimp grip twice a week for 8 weeks with a regime
of 3–5 sets, an effort duration of 10s per set never
reaching the point of muscular failure (leaving 3 s in
reserve according to Gonza
´lez-Badillo’s line of
research about the perceived effort; Gonza
´lez-Badillo
& Ribas, 2002), and a pause of 3 min between sets.
Half crimp was chosen because it is the most widely
used grip in climbing to grab small edges (Quaine &
Vigouroux, 2004; Schweizer, 2001; Watts, 2004),
Figure 2. Execution of strength test (ST).
Eva Lo
´pez-Rivera & J. J. Gonza
´lez-Badillo4
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and is safer than the full crimp. The methods differed
in the adjusting of the load: one used minimum edge
depth without added weight (MED) and the other
used bigger edge with maximum added weight
(MAW). Group A (n¼5) performed MED for 4
weeks (training phase 1), and for the following 4
weeks (training phase 2: week 6 –9) performed MAW
(Group A referred to as MED –MAW). Meanwhile,
Group B (n¼4) used both methods in reverse order
(Group B referred to as MAW– MED).
Figure 3. Depth used for the strength test: 15 mm.
Figure 4. Depth used for endurance test: 11 mm.
Figure 5. Execution of endurance test (ET).
The effects of two maximum grip strength training methods in elite climbers 5
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Training with MAW. It was performed on an 18-mm
edge, after 3–4 warm-up sets of the training exercise
with progressively heavier weight (50% –90% of the
previous session’s added weight). Each participant
chose their added weight for the first training set of
each session as follows: the weight should allow
participants to hang for 13 s, but the effort duration
would be for 10 s in any case; if this perceived 3-s
margin was to be exceeded, the added weight for the
next set would be increased (2 –5 kg as a function of
body weight). In contrast, if the margin were to be
closer to 0 s, some weight would be removed (2 –5 kg
as function of body weight). As a reference, the
strongest climber used up to 55 kg and the least
strong used up to 25 kg. During the following sets
that made up the session the weight was varied if
needed so that the perceived effort was even
throughout the training session. The number of sets
per session is detailed in Table IV.
Training on MED. It was performed without additional
weight. It was preceded by 3– 4 warm-up sets of the
training exercise, each with a progressively smallest
edge (8 –2 mm deeper than the one used in the
previous session). Each participant chose the
minimum depth for the first training set as follows:
the first edge was chosen so that he or she could hold
it for 13 s but would hang just for the prescribed 10 s.
The depth of the edge for the next set could be
increased or decreased by 1 or 2 mm according to the
perceived effort. If the perceived 3-s margin was
exceeded, the depth of the edge was decreased by 1–
2 mm; if it approached zero, the depth was increased
by 1–2 mm. The edge size was adjusted from one set
to the next in order to control and maintain the
perceived effort throughout the training session. The
smallest edge that an individual used had a depth of
5 mm, and the biggest, 10 mm. The number of sets
per session is detailed in Table IV.
Technical and physical training. It was carried out
6 days a week (Friday being rest day) 2 –4 h a day,
observing a 30-min rest period after the finger
maximum strength training. It was performed on an
artificial climbing wall and consisted of boulder,
endurance and/or power endurance training with 3 –
10 sets of 3 –90 moves with a difficulty between 70%
and 100% of the maximum sport level. This training
was tailored to the characteristics and goals of each
participant, and was designed, revised and managed
by Eva Lo
´pez.
Statistical analysis
Descriptive statistics were used to derive means and
standard deviation for all variables.
Reliability of ST and ET was estimated by using a
one-way random repeated measures analysis of
variance (ANOVA) and intra-class correlation coeffi-
cient for test–retest. To detect intra- and inter-
group differences a repeated measure ANOVA with
Bonferroni adjustment was used. The effect size
between pre- and post-training for each group was
calculated using Hedges’ g(Hedges & Olkin, 1985),
represented by the following formula: g¼M
post
2
M
pre
/SD
pooled
,whereM
post
is the mean post-training
measure, M
pre
is the mean pre-training measure for
each group and SD
pooled
is the pooled SD of the pre-
and post-measurements. The effect size was definedas:
trivial, ,0.25; small, 0.25– 0.50; moderate, 0.50– 1
and large, .1 according to the scale for strength
training interventions on highly trained (at least 5 years
of training) individuals proposed by Rhea (2004).
Pearson’s correlation was applied to investigate the
relationships between variables. Differences between
means and correlations were considered significant
when p,0.05.
Results
Reliability of STwas estimated to be 0.93 (ICC) for one
measurement (95% confidence interval 0.77–0.98)
and 0.96 for the mean (95% confidence interval
0.87– 0.99); the coefficient of variation (CV) was
7.8%. For ET, ICC for one measurement was 0.86
(95% confidence interval 0.56– 0.96) and 0.92 for the
mean (95% confidence interval 0.72– 0.98); CV was
12.8%. No significant differences were found in
strength and endurance of both intra- and inter-groups
for the initial tests. Table V shows the results
(mean ^standard deviation) for the maximum
strength and endurance tests.
The greatest maximum strength changes in
percentage were obtained by MAW–MED group in
ST2 and ST4 (9.6% and 6.9% against 2.1% and 0.6%
for MED– MAW group). Both groups had strength
losses in ST5, especially MED– MAW group (25%
against 20.3% for MAW–MED group). Although
the MAW–MED group increased the most, no
statistical differences were found in both intra- and
inter-groups. Both groups demonstrated greater gains
in maximum finger strength between ST1 and ST2
than between ST1 and ST3.
The two groups showed a remarkable improvement
in endurance that did not result in statistically
significant differences, both intra- and inter-groups.
MAW –MED group demonstrated greater gains in
ET2 and ET3 (16.69% and 19.95%, respectively), and
MED–MAW group in ET3 (16.30%). Both lost
endurance in ET5, particularly MAW– MED
group (22.59%).
The biggest losses compared to the maximum
attained values occurred in Week 14, four weeks after
Eva Lo
´pez-Rivera & J. J. Gonza
´lez-Badillo6
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quitting the training object of the study, in maximum
strength (29.9% for MED–MAW group and 26.9%
for MAW –MED group compared to the maximum
obtained in ST2) as well as in endurance (Group A,
218% and Group B, 222.54% compared to the
maximum obtained in ET3).
Effect size (ES) was calculated to be 0.1 and 0.4 for
MED–MAW and MAW–MED in ST2, respectively.
For ST4, only MAW–MED group showed effects
(ES ¼0.2). For ET2, both groups showed an increase
during the first 4 weeks, especially MAW–MED
group (ES ¼0.5 against 0.2 for MED–MAW group).
During the following 4 weeks (ET3) both groups
improved, but again MAW –MED group registered
the larger ES (0.7) against a small ES (0.3) for MED–
MAW group. MAW –MED group experienced the
biggest losses with an ES ¼20.4 in ET4 and
ES ¼20.8 in ET5 against ES ¼20.1 and
ES ¼20.5 for MED– MAW group (Table V).
A nearly significant positive correlation was found
between the results of the initial tests ST1 and ET1
(r¼0.59; p¼0.06). Nonetheless, given that the
control for body weight could influence the degree of
correlation, partial correlations were applied control-
ling for body weight to those variables, and also to the
changes in strength and endurance for all stages; the
relation between ST1 and ET1 increased and results
were statistically significant (r¼0.85; p¼0.016).
Controlling for body weight had a similar effect on
the relation between the changes in strength from ST1
to ST2 and the changes in endurance from ET1 to ET2
(r¼0.76; p¼0.046); between changes in strength
from ST1 to ST3 and changes in endurance from ET1
to ET3 (r¼20.76; p¼0.048); and between the
changes in strength from ST1 to ST4 and the changes
in endurance from ET1 to ET4 (r¼0.84; p¼0.018).
Discussion
To the best of our knowledge, this is the first study to
compare different grip strength training methods
using a climbing-specific device and exercise in elite
rock climbers. From the results obtained from this
study, the most important findings have been:
.The most effective training sequence to improve
grip strength and endurance is to do the 10-s dead
hanging with added weight and an edge depth of
18 mm and then proceed to dead hanging without
added weight on the smallest edge depth that
allows the participant to suspend themselves for
10-s intervals.
.A highly significant correlation between changes
obtained in strength and changes obtained in
endurance.
To interpret and contrast the results, it is important
for us to note two things: (1) the participants were of a
high level, at which it is harder to improve, and (2) we
have not found works that analyse climbing and the
effect of strength training with loads, so we have
reviewed other studies that have analysed this in other
sports or at a more general level.
Improvements in strength
The biggest improvements occurred at 4 weeks of
training (ST2) for the groups (þ2.1% and þ9.6% for
MED –MAW and MAW –MED, respectively). This is
in accordance with a study that found improvements
within the first weeks among athletes of medium and
high levels who obtained training with loads higher
than 80% of 1 RM (one repetition maximum;
Ebben, Kindler, Chirdon, Jenkins, Polichnowski, &
Ng, 2004; Judge, Moreau & Burke, 2003; Kraemer,
Table V. Results (mean ^sd) for maximum strength test (kg) and endurance test (seconds).
MED– MAW group MAW–MED group
Maximum strength kg ES kg ES
Initial test ST1 39.68 ^17.52 48.52 ^11.31
Training ST2 40.50 ^15.15 0.1 53.18 ^12.78 0.4
ST3 40.50 ^15.15 0 49.18 ^12.81 0.1
Detraining ST4 39.90 ^16.23 0 51.88 ^10.70 0.2
ST5 37.70 ^16.67 20.2 48.40 ^9.60 20.1
Endurance seconds ES seconds ES
Initial test ET1 51.81 ^10.76 46.62 ^14.53
Training ET2 57.78 ^11.48 0.2 54.40 ^16.21 0.5
ET3 60.56 ^16.05 0.3 55.92 ^13.86 0.7
Detraining ET4 60.25 ^14.71 20.1 50.61 ^15.09 20.4
ET5 51.24 ^11.28 20.5 45.41 ^13.38 20.8
MED– MAW group ¼4 weeks training with the minimum edge depth without added weight, and then 4 weeks training with maximum
added weight on 18 mm edge; MAW– MED group ¼4 weeks training with maximum added weight on 18mm edge, and then 4 weeks
training on the minimum edge depth without added weight. The improvements in strength and endurance were not statistically significant
(p.0.05). ES ¼effect size. The ES was defined as: trivial, ,0.25; small, 0.25 –0.50; moderate, 0.50 –1; and large, .1 according to the
scale for strength training interventions on highly trained individuals proposed by Rhea (2004).
The effects of two maximum grip strength training methods in elite climbers 7
Downloaded by [Eva López Rivera] at 07:52 21 August 2012
1997; Rhea, Alvar, Burkett, & Ball, 2003). These
studies suggest that improvements during the first
weeks can be explained by neural adaptation.
At 8 weeks, there were hardly any improvements
compared to the gains after 4 weeks, but there were
losses. The MAW–MED group suffered the biggest
loss (28.3% against 0.5% for the MED–MAW
group), perhaps due to the change in stimulus, i.e.
training without weights. The MED–MAW group,
trained with added weight in this second stage, did not
increase in strength, in contrastwith what was observed
in MAW–MED after added weight training. This is
thought to be caused by the MED method producing
an increased level of fatigue from which the participant
could not recover enough to be able to work afterwards
with bigger loads.
As for the improvements within each group, the
biggest, remarkable gain was obtained at ST2 for
MAW –MED group that trained with weight, which
was almost 10%. This increase is comparable to that of
Rhea et al. (2003) after a 15-week training programme
wheregainsof9.8%in1RMwereobtained.
Nevertheless, they are smaller than those measured
by Judge et al. (2003) among high-level throwers after a
maximum strength training where volume and
intensity were raised during 16 weeks; they found a
significant increase of 15% in maximum isometric
strength. This may be due to the fact that the athletes
were not of a high level, so bigger performance gains
were to be expected. This is not the case in this study,
where the participants were of a high level; thus, a 9.6%
increase in maximum strength can be considered
significant.
Another notable result was that of MAW– MED
group’s increase in strength in Week 12, after 2 weeks
of rest (þ6.9% against þ0.6% for MED–MAW
group). We believe that this can be attributed to the
effect of the rest itself; and is in accordance with
Gibala, MacDougall & Sale, (1994), who registered at
the 6th and 10th day of a decrease in load, there were
increases in strength of 7% and 9%; which stresses the
need for a rest period for it to have an effect on strength
performance.
However, at Week 14 or 4 weeks of rest, both groups
suffered important losses (24.99% in MED– MAW
group and 20.27% in MAW–MED group). These
losses are in agreement with those obtained in some
works after 10 days or 3 weeks of rest (Gibala et al.
1994; Hakkinen, Alen, Kallinen, Newton & Kraermer,
2000; Hortobagyi, Stevenson, Fraser, Johns & Israel,
1993). An explanation for this decrease in strength is
given by Hakkinen, Komi & Alen (1985a), who assess
the effects occurred during the detraining period and
found a significant correlation between the loss in
maximum strength and the reduction in maximum
neural activation ( p,0.05) in the leg extensors due to
the break in training stimulus.
The most important part of this discussion is the
significant increase in strength obtained by MAW –
MED group, whowere the group that trained first with
weight and then without it. The explanation of this
great effect could be that the use of loads while in dead
hanging from a deeper edge provokes major muscular
activation and recruitment of motor units, which in
turn causes a bigger increase in grip strength than
hanging off a smaller edge without added weight. This
coincides with studies showing that there is higher
muscular activation and recruitment of motor units
when training with added weight (Hakkinen et al.
1985a, 1985b; Sale, 1988). In addition, the added
weight dead hanging differs more from the usual
climbing training than the small hold dead hanging.
This may provide an extra stimulus and lead to higher
adaptation processes.
Improvements in endurance
With endurance, it was also the MAW– MED
group who improved the most (16.69% and 19.95%
against 11.53% and 16.90% for MED –MAW
group in ET2 and ET3, respectively). These
improvements are in line with the improvements of
13% in the distance run in Hickson et al. (1988),
or 13% of the time until fatigue caused by lactic acid
in the study by Osteras et al. (2002) on participants
who performed previously a 3-week strength training
routine of three series of 5 RM. An explanation of this
fact can be that by increasing maximum strength,
body weight represents a smaller load during the
exercise, so less motor units need to be activated for
the same load and there is a potential for recruitment
of bigger numbers of non-fatigued units. This delays
the intervention of Type II fibres (Hickson et al.
1988), and the build-up of lactic acid, allowing an
extension of the time until exhaustion (Marcinik et al.,
1991).
The MAW–MED group, by training without
added weight on a smaller edge depth after having
made improvements with added weight on a deeper
edge, kept improving endurance, probably because of
the similarity of the exercise being performed to that
of the test.
However, after 2 and 4 weeks of detraining, the
major losses are found in the MAW – MED
group (211.40% and 222.54% against 0.60% and
28% in MED–MAW group), which is in accordance
with a number of studies where the participants
significantly lost what had been gained after abandon-
ing the training with weight (Hakkinen et al. 1985a,
1985b; Hakkinen et al., 2000 & Kraemer et al. 2002).
From a practical point of view, the improvements in
strength and endurance for both groups can be
considered to be of note because, as has already been
shown, maximum grip strength (MacLeod et al. 2007;
Eva Lo
´pez-Rivera & J. J. Gonza
´lez-Badillo8
Downloaded by [Eva López Rivera] at 07:52 21 August 2012
Watts, 2004; Watts et al. 2003) and grip endurance
(Grant et al. 1996; Scho¨ ffl et al., 2005; Wall, Starek,
Fleck & Byrnes, 2004) have a high relationship with
climbing sport level. However, probablydue to the low
number of participants (MED–MAW group, n¼5;
MAW –MED group, n¼4), these findings were not
statistically significant. Since the MAW– MED
group showed the biggest increase in both
grip strength and endurance, the training combination
they followed (MAW –MED) can be inferred to be
more effective than the opposite one (MED– MAW).
Correlation between strength and endurance
Apart from these findings, a positive correlation was
found between initial grip strength and grip endurance.
However, as it is the case in the study by Guidi (1994,
n¼13), it was possibly due to the small sample size
that the finding was not significant. A greater
relationship between these two variables could be
hidden by the influence of body weight, which was
tested by performing a partial correlation (r¼0.85;
p¼0.016). These results are in line with those of
Janot, Mermier, Parker & Robergs (1999), who found
a positive relationship of 0.78 between the maximum
strength divided by body weight and performance
level. Likewise, other authors have observed that the
relationship between finger strength and body weight is
more significant at a high performance level (Lehner &
Heyters, 1998; Mermier, Janot, Parker & Swan 2000;
Watts et al., 1993). Thus, our results suggest that
maximum strength plays a relevant role in climbing,
which is amplified if the effect of body weight at the
time the participant is able to hold the edge is excluded.
Another important finding is the positive significant
correlation that exists between the changes in
grip strength and endurance at 4 and 8 weeks of
training, and after 2 and 4 weeks of detraining,
controlling for body weight in all cases. The results
match those of Robinson, Stone, Johnson, Penland,
Warren & Lewis, (1995), who obtained a significant
correlation of 0.75 between the improvement in 1 RM
and the sum of all the power peaks during a 15-pedal
stroke series on a cycle ergometer. In no other study,
has a relationship been quantified, although numerous
authors have observed that after strength training of
3£5 RM, the improvements in strength come
accompanied by improvements in endurance (Hickson
et al. 1988; Marcinik et al., 1991; Osteras et al. 2002).
However, Alricsson, Harms-Ringdahl, Linder,
Larsson, & Werner (2004) did not find a correlation
between the improvement in strength and endurance
although they did obtain improvements of 10% in
isometric strength and endurance after training the
neck flexors and extensors using 3 £10 repetitions.
According to the above study, it could be attributed to
the individual differences between participants, so it
seems that the strongest participants were not the ones
with the longest endurance time, and vice versa.
Conclusions and practical applications
The most effective method is to perform the training
first on a bigger edge with added weight and then on a
smaller edge without weight. The improvements were
not statistically significant because of the small
number of participants (MED–MAW group, n¼5;
MAW–MED group, n¼4). Training maximum
strength on a bigger edge improves endurance on
smaller edges as well, as it is obvious from this fact that
there exists highly significant correlation between
changes in strength and changes in endurance.
To increase strength and endurance by 10% and
20% can be considered a remarkable improvement for
high-level athletes, because both the ability to hold
smaller edges and maintain grip strength for longer
periods of time often determine a successful climb and
make for substantial differences in competition. Also,
it is probably not convenient to quit maximum
strength training with weight for more than 2 weeks.
To the best of our knowledge, this is the first study to
compare different grip strength training methods
using a climbing-specific device in elite rock climbers.
Our findings may help coaches to better prescribe
finger strength training programmes in sport climb-
ing. Another advantage is that many climbers can
easily build this device and put in practice these
methods.
Future studies
It would be interesting to check if there were
significant inter- and intra-group differences if a
larger number of participants trained for a longer
time using the training method found as most
effective in this research.
It would also be of interest to assess the effects of
three different training methods on maximum finger
strength and endurance over an 8-week cycle during
which Group A would perform only the maximum
strength training method suggested in this research as
the most beneficial (MAW– MED), Group B would
undergo endurance training with moderate loads and
incomplete recovery and Group C would combine
both types of training.
Judging the validity of the training presented in this
study by checking its effects over performance on an
actual climbing route would also be necessary, given
that such a study is yet to be undertaken.
Acknowledgements
The authors would like to express their deepest
gratitude to Dafnis Ferna
´ndez for the design and
manufacturing of “El Regleto
´metro” the test and
The effects of two maximum grip strength training methods in elite climbers 9
Downloaded by [Eva López Rivera] at 07:52 21 August 2012
training apparatus. The authors declare that they
have no conflicts of interest. Eva is deeply indebted
also to the climbers from Toledo and Madrid who
took part in this study (“test persons for climbing
science”), and to Dafnis, Ana, Luis and family for
their priceless support.
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