Wednesday, May 23, 2018

Fingerboard Training Guide (II). Maximal grip Strength and Endurance Methods and Load Training management

Versión en español

I. The current state of affairs: Preliminary Evaluation
This topic was addressed in the first part of this series. You can read it here.

II. Methodology

2.1. Naming Conventions and Training Methods
In case you aren’t aware of the terminology we will explain it through examples of each method.

2.1.1. Maximal dead hangs on the minimum edge depth (MED hangs), no added weight.

3-5 x MED Hangs x 5”-15” (1-5) :3’-5’

EXAMPLE: 2 x MED Hangs  x 12” (3) :3’

The first number (2) indicates the number of sets; after the “x” we write the name of the method or protocol and exercise (MED = minimum edge depth; Hangs = dead hangs); what follows is the duration of each dead hang in seconds and the effort level (EL) or margin in parentheses; last is the rest interval length indicated by the colon. It reads like this:

“Perform 2 sets of dead hangs on the smallest edge that would allow you to hang for 15 seconds max, but do just 12 to keep a margin of 3 seconds; rest 3 minutes between sets”.
Traning MaxHangs MED on Transgression board. Photo: Javipec.

This term was proposed by González-Badillo & Gorostiaga in 1993 and was called ‘carácter del esfuerzo’ in the original Spanish. Some English-speaking authors like Schoenfeld (2016) have used alternative terms like ‘intensity of effort’ to refer to the same concept.

The particular layout we use to describe a session puts the EL between parentheses, to the right of the effort duration for each set. The effort level tells us how close to our limit we get, the difference between the # of seconds or reps that we could possibly do and how many we actually do. In other words, how many seconds (or repetitions) we leave before muscle failure. The closer to our limit, the higher the EL and the more fatigued we get. We can also think of it as a margin, buffer, distance to failure or ‘repetitions in reserve’ (RIR; Steele et col., 2017).
When we are working our maximal strength with methods that seek neural adaptations through the use of high loads, the effort level is one of the parameters that will help us monitor and adjust the load. The reason is twofold:

  1. It has been shown that leaving a margin yields similar results than reaching failure as far as these methods are concerned, with the bonus of reduced risk of overuse and injury, and faster recovery between sessions (Davies et al., 2017; Morán-Navarro et al., 2017; Sampson & Groeller, 2016).
  2. Additionally, controlling the intensity of each set via the margin ensures we achieve the desired results in contrast to reaching failure in each set (Sánchez-Medina, 2010). The latter modality makes us remove some added weight or choose a deeper edge for each successive set due to fatigue. The physiological consequences (lactate, uric acid and ammonia buildup) are associated to the glycolytic pathway and phosphagen depletion (González-Badillo & Sánchez-Medina, 2011), which would trade the neural adaptations we seek for others, conducive to changes in endurance instead.

The practical application of this concept in MaxHangs is shown in this video.

2.1.2. Maximal dead hangs with added weight (MAW hangs)

In this method we start by choosing one edge size:
3-5  MAW Hangs x 8mm-20mm x 5”-15” (1-5) :3’-5’
Only Babette Roy can train weighted hangs on that edge size. Gym: Allez up centre d'escalade (Montreal, Canada). Hangboard: Transgression board. Source: Instagram. Photo courtesy of Babette.

EXAMPLE: 3 x MAW Hangs  x 18mm x 10” (3) :3’

And that reads: Repeat 3 times (sets) the dead hangs exercise with a 18mm-deep edge, adding enough extra weight to last 13 seconds, but hanging just for 10 seconds to honor the 3-second margin; recover for 3 minutes between sets.
This figure helps learning the MaxHangs nomenclature. It is part of the Transgression and Progression training guides, that will be available for purchase separate from the fingerboards shortly.

2.1.3. Intermittent dead hangs (IntHangs) on the minimum edge or with added weight

Check this blog post to learn more about this method.
No added weight:

3-5 x 4-5 x  MED IntHangs x 10”-7” :3”-30”/2’-1’

Performed with added weight (advanced, ample training experience needed):

3-5 x 4-5 x MAW IntHangs x 10mm-18mm x 7”-10” :3”-30”/2’-1’

EXAMPLE: 3 x4 x MED MaxHangs x 10” :20”/2’
The long version: Perform 3 sets, comprised of 4 repetitions each, of 10-second dead hangs with a 20-second pause between repetitions and 2 minutes between sets; the edge will be the smallest that allows to complete all the repetitions.

You’ll have noticed the lack of a margin before failure indication, but this is by design because here we want to reach failure in the last repetition of the last set, but not before. To achieve that, we have to learn to manage the intensity by choosing the edge depth carefully, based on our perception of effort.
The basic nomenclature for the MED IntHangs method.

2.1.4. Submaximal dead hangs (SubHangs), on the smallest edge or with added weight
This is the first appearance of Submaximal dead hangs (SubHangs) in this blog. The configuration is similar to that of MaxHangs, with the difference that longer hanging times have effects on grip endurance, and presumably on maximum strength via hypertrophy. Your hangboarding workout in this context requires the optimal combination of mechanical tension and metabolic stress (Schoenfeld, 2016), so I recommend pauses between sets longer than 1 minute to maintain the intensity (edge size or added weight) reasonably stable throughout the session.

When opting for MED the edge will obviously be much bigger than the MaxHangs one; as for MAW, I’d only prescribe them to someone with a high or elite level very familiar with advanced finger training.

4-8 x MED Hangs x 20”-45” :30”-2’
4-8 x MAW Hangs x 14mm-20mm x 20”-45” :30”-2’ (really advanced method)

It is advisable to start with a longer pause, 2 or even 3 minutes, and shorten it step by step, down to 90” or 30” while keeping the hang duration or the edge size constant; alternatively you can increase the hang time and keep the pause unchanged. Which one suits your needs better? Your goals will inform your choice: the need to have a quick recovery between efforts or hold the grip on a particular hold size for the longest possible time.

2.2 Load Training Management
It is vital to control the training load day by day, exercise by exercise and of course, set by set. Intensity is the key variable in strength training. As climbers this translates into the need to make sure the hold size or the added weight are in tune with the pre-set method requirements. In short: honoring the programmed hanging time and margin in order to obtain the desired training effects.

2.2.1. Determining and controlling intensity in the MaxHangs method
Before choosing the load for the first set we must warm-up, doing 3-4 dead hangs if you have already done some climbing on the wall, or 6-8 otherwise. Other factors like individual characteristics and temperature can condition warm-up volume. These initial sets will be progressively harder, from 50% to 90% of the training added weight or hold depth; the last set helps us guessing the load required to comply with the effort duration and the margin for the day, and we should get near failure in this set to accomplish it. The way I see it, you only need this procedure the first time you start performing a method.

Once we have a baseline, we will employ this approach in all subsequent sets and training days: if you feel you won’t comply with the EL, the solution is to add or remove added weight as necessary, or change to an easier or harder edge in order to keep a constant load. Guessing your time to failure seems difficult and not very precise, but it doesn’t take long to learn it, and accuracy improves with experience, based on my own experience and recent research (Steele et col., 2017). Training always to failure does not require this cognitive investment, but as we have already mentioned the drawbacks are not worth it (Morán-Navarro et col., 2017).

Suppose your planning for today prescribes hanging for 12 seconds off an edge that you could hold for 16 seconds (4” margin), and you have chosen a 20mm edge; warming up or in the first set you realize your maximum time would be 13 seconds (1” margin), so you change to a 22 or 24mm edge. The process is the same in MAW but adding or removing weights (2-5 kg depending on body weight and perception).

Here you can watch a video on handling the load in a MAW Hangs workoutand in a MED Hangs workout. Body posture and general execution are important to avoid injury. The right technique is shown in this video.

2.2.2. Determining and controlling Intensity in IntHangs and SubHangs
Before choosing the load for the first set we must warm-up, doing 3-5 dead hangs if you have already done some climbing on the wall, or 8-10 otherwise, Other factors like individual characteristics and temperature can condition warm-up volume. These initial sets will be progressively harder, from 50% to 90% of the training load, adding weights or reducing edge depth. The effort duration will be similar to the training one, for example doing sets of 10 seconds with 10-second long pauses for IntHangs and longer, or around 30-second hangs for SubHangs. The last warm-up set should help you guess the initial weight or hold size for the day, which is not set in stone and can change from one set to the next.

Having determined this initial training load we should repeat the above procedure in each set, each session. The goal here is to end the session with failure, and guessing the right weight or edge from the get go is unlikely, making corrections on the fly to finish all the reps and sets (IntHangs) or all the sets (SubHangs) is part of the game. Failing too soon or not failing at all will have a different effect than the one we were aiming for when designing the exercise.

2.3. What hangboard should I choose?
When we focus on constantly controlling the intensity and personalizing the training, access to a variety of weights and edge sizes makes our life a lot easier; the Progression and Transgression boards have you covered, but there are other options for different kinds of holds, like slopers. A cheaper alternative is having several wooden rungs with varying depths, or building your own adjustable edge or adjustable sloper (see pictures below).
The TRANSGRESSION board offers 6, 7, 8, 9, 10, 12, 14 y 18 mm edges.
Source: Surfaces for Climbing
The PROGRESSION board offers 10, 12, 14, 16, 18, 20, 22 y 24 mm edges. Fuente: Surfaces for Climbing
 If you are on a budget, you can build and install the edge sizes you need. Source:
These DIY contraptions are cheap and use recycled materials but still allow you to change how hard the hold is to grip, making it possible to manage the load and carry out a progressive and personalized training program. Left: our adjustable sloper; right: the adjustable edge, built to test and train strength on edges for my first research works in 2004.

The width of the device/edges should be around 50 cm, so you can place your hands at the distance of your elbows or a bit wider and thus decrease the chance of overload due to excessive pronation in the pronator teres, wrist or elbow.

Remember that training the open hand grip with 1, 2 or 3 fingers calls for holds with rounder lips. If your edges are long enough you can make some sections blunter with a file or sandpaper, leaving a more aggressive profile in other parts to use the half crimp.

NEXT IN THIS SERIES: Periodization Patterns to design your own training plan, and some MaxHangs and IntHangs planning examples.


  • Davies, T, Orr, R, Halaki, M, and Hackett, D. (2016). Effect of Training Leading to Repetition Failure on Muscular Strength: A Systematic Review and Meta-Analysis. Sport Med 46: 487–502, 2016.
  • Sánchez-Medina, L., & González-Badillo, J. J. (2011). Velocity loss as an indicator of neuromuscular fatigue during resistance training. Medicine & Science in Sports & Exercise, (22), 1725–1734.
  • González-Badillo, J. J., Marques, M. C., Sánchez-Medina, L.  (2011). The Importance of Movement Velocity as a Measure to Control Resistance Training Intensity. Journal of Human Kinetics, 29 (Special Issue), 15–19. 
  • González-Badillo, J.J., & Gorostiaga, E.. (1993).  Fundamentos del entrenamiento de la fuer za. Aplicación al alto rendimiento deportivo.
  • Morán‑navarro, R., Pérez, C. E., Mora‑rodríguez, R., De La Cruz‑sánchez, E., González‑Badillo, J. J., Sánchez‑Medina, L., … Pallarés, G. (2017). Time course of recovery following resistance training leading or not to failure. Eur J Appl Physiol, 117(12), 2387–2399.
  • Sampson, J. A. & Groeller, H. (2016). Is repetition failure critical for the development of muscle hypertrophy and strength? Scandinavian Journal of Medicine and Science in Sports, 26(4), 375–383.
  • Schoenfeld, B. (2016). Science and Development of Muscle Hypertrophy. Human Kinetics.
  • Steele, J., Endres, A., Fisher, J., Gentil, P., & Giessing, J. (2017). Ability to predict repetitions to momentary failure is not perfectly accurate, though improves with resistance training experience. PeerJ, 5(November), e4105.
  • Sundrup, E., Jakobsen, M. D., Andersen, C. H., Zebis, M. K., Mortensen, O. S., & Andersen, L. L. (2012). Muscle Activation strategies during strength training with heavy loading versus repetition to failure. J Strength Con Res, 26(7)M 1897-1903.

Thursday, May 17, 2018

Fingerboard training guide (I). Preliminary evaluation

Versión en español

We have already talked extensively about how, why and what effects do Maximal Hangs (MaxHangs) and Intermittent Hangs (IntHangs) have on grip endurance and strength. What follows is the start of a series where we will put all those results into practice.

I will suggest a set of guidelines to build a training program; we will see how to progressively modify volume and intensity for each method. Later we will review some MaxHangs and IntHangs planning proposals, and learn when to use them (by themselves or combined) according to your short-, mid- and long-term goals.
Disclaimer: the guidelines and planning that I’m going to put forward are just a subset of all the possible combinations that can yield positive results, which include those proposed by other authors and, of course, the ones that you will create. Anyway, to help you make informed decisions I think it is a good idea to go step by step. Here we go!

I. The current state of affairs: Preliminary Evaluation
There are some questions you need to ask yourself before submitting your fingers to such an intensive and specific method to make sure it will benefit your performance:

1.1. Have you been climbing and training in a systematized fashion for more than 2 years?
Systematized means training or climbing 2-3 days per week, with some consistency and order, specially for the last year, given that the first couple of years it is normal to have a less organized approach to the sport.

On the other hand, this requisite acknowledges that while muscles can adapt to the sport in a matter of months, other structures like capsules, cartilages, tendons and ligaments take years to develop the mechanical adaptations (thickness, tensile strength, etc.) needed to safely perform dead-hangs. Based on my experience and what literature says, I would suggest two to three years as a reasonable interval.

The following question is important although it can overlap slightly with the previous one:

1.2. Do you have an average technical-tactical repertoire?
If you don’t have a lot of spare time for training and are wondering whether to invest part of it on training your fingers, would that detract from the much needed technical gains that you would achieve by climbing in the gym instead and are so important in the early years?
Johnny Dawes. Source: Into the Wild Blog
1.3. Are you 16 or older? Are you past your growth spurt?
The works of  Morrison & Schöffl (2007)  and Schweizer (2012) show correlation between intensive finger training and the use of the crimp grip before puberty and the incidence of severe injuries like stress fractures. The most dangerous period is the growth spurt that takes place at age 11-12 in girls and 13-14 in boys, but the risk remains until the growth plates (the zone where the bones grow) are closed.

Regularly using the full crimp and the half crimp under high loads, like grabbing tiny holds or applying high acceleration on medium ones, can harm an adult’s ligaments, sheaths, capsules, tendons or ligaments, while a youngster can experience from sporadic inflammation and pain to tears, fractures and chronic deformity. The problem is that this tissue is 2-5 times weaker than its surroundings, and one of them is located just where it meets the flexor digitorum superficialis (see picture below).
 When crimping, the dorsal area at the base of the medial phalanx bears a considerable tension precisely where the growth plate is located (copyright by Swiss Medical Weekly, 2012, 142, 1–9)

By the way, we should take this into account when designing our climbing classes and setting routes and boulders in the gym or in competitions.
Iziar Martínez Almendros, a promising climber competing at the “Open La Ola 2017” in Salamanca, Spain. Source: Instagram
If you are still interested in kids developing some grip strength don’t worry, there is a blog post coming to help you precisely with that.

1.4. Are you injury-free? Do you suffer from any condition that makes finger training inadvisable?
Have you adequately recovered from your last injury?

The less severe lesions take at least 2 months to heal, others can take 6 or more. In truth, once the subacute phase is over and reconditioning work starts, dead-hangs are not out of the question. An experienced physical therapist can guide you through a routine of analytic exercises followed by assisted dead-hangs (with rubber bands or pulleys) on deep, rounded holds. In all cases the programs will NOT be the ones recommended in this series.

1.5. What are your level and objectives?

1.5.1. Is your finger strength low, but not ‘very low’?
Check this with the following test on a 25 mm edge (one phalanx and a half):

- If you can hang for 15 seconds you could start doing dead-hangs as a method to develop your grip strength.
- If your time is less than 15 seconds I’d suggest you work your fingers by climbing instead of using an analytic method. Remember my philosophy: “Use the easiest dose, exercise and method that still makes you improve”. If I were you, I’d rather keep on developing my strength by climbing than doing hangs on a deep edge or a bar; instead, you could:
- Occasionally climb on steeper (more overhanging) walls than you are used to.
- Including some (10-20%) small foot- and handholds in your training routes or boulders.

Gekoaventura, Indoor Adventure and Climbing Park in Valladolid, Spain.
It’s still possible that you like to try every kind of method from the very beginning, and you have the time and capacity for it; in the end the choice is always yours.

1.5.2. Using a percentile table to assess the starting level
We can add some extra information to the test above by getting an idea of our position relative to a climber population. I built a percentile table based on data from a 2004 study of maximal hang time on several wooden edges (6, 8, 10, 12 and 14 mm) that was part of my thesis (n=37, levels 6a to 8c+). However, please be aware that the sample size is small and that in the intervening 14 years the population level must have changed. In this line, we have to take in account that this statistical measure is dependent on the study sample features (Spanish climbers, living in Toledo and Madrid, who trained and climbing in specific areas...) so you should be cautious when interpreting it. You can take it as a curiosity. Furthermore, you also need to follow the standardized test protocol (check my Doctoral thesis) to be able to compare the results.

The percentile is a measure that tells us in what position a mark is with respect to a population. In this table, if your maximum time on 14 mm is 30 seconds, then you are approximately in the 25th percentile, which means that in a representative sample of 100 people around 25 would have a worse time than yours and around 75 would do better than you.

As an interesting aside, the 14 mm test was the most reliable and showed a significant positive correlation with sport level. This means that it could be used for predicting performance or even detecting new talent, but always as part of a suite of metrics that measure other physical, technical, tactical, psychological or anthropometric aspects.

Three broad categories can be established based on the table:
Lower level: those equal or below the 25th percentile, like hanging for less than 10 seconds off a 10 mm edge.
Intermediate level: between the 25th and the 75th percentiles.
Higher level: above the 85th percentile.
1.5.3. Objectives and training grip type
If your usual climbing spot or your choice project require climbing on edges, specially at the crux, it’s advisable to train the half crimp or the open crimp (check this series to learn about grip types). If, instead, it’s mainly pockets or slopers it will be a good idea to train the open hand. For training your pinch strength, have a look at this blog post.

Anyway, if you have the capacity, time, experience and level (medium to high) consider training 4 days/week with 2 days for each grip type and 48h rest between them, or work both the same day reducing 25-30% the volume of each grip; for example, instead of doing 3 sets of half crimp and 3 of open hand, do just 2 of each. If you need to choose one grip type do it attending to your weaknesses or, by the contrary, looking at what increases your immediate chances of success.

Here ends the first phase of “Designing your own dead-hangs training plan”. The next article will tackle Methodology: naming conventions and methods: MinEd, MaxW, IntHangs, load management and which fingerboard to choose.

-Why do intermittent dead hangs?
López-Rivera, E. y González-Badillo, J.J. (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. Sport Technol 5: 1–11.
Abstract of my article studying the effect on finger endurance of Max Hangs vs. Int Hangs vs. a combination.
-Some hangboarding Instructional Videos
Intermittent Dead Hangs Programs for Your Smartphone-Complex Timer: A Training app for Climbing
Published Research Article, and a Summary of the Guidelines on finger strength Methodology described in this Blog
#1 Doubts about finger training — The Arch Climbing Wall

  • Balyi, I., & Hamilton, A. (2004). Long-Term Athlete Development: Trainability in Childhood and Adolescence, Windows of Opportunity, Optimal Trainability. Victoria, British Columbia, Canada: National Coaching Institute British Columbia and Advanced Training and Performance Ltd.
  • Canadian Sport for Life. (2017). Sport climbing for sport, for life. LTAD Long Term Athlete Development. Canadian Sport for Life.
  • Morrison, A. B., & Schöffl, V. R. (2007). Physiological responses to rock climbing in young climbers. British Journal of Sports Medicine, 41(12), 852–861; discussion 861.
  • Schweizer, A. (2012). Sport climbing from a medical point of view. Swiss Medical Weekly, 142(October), 1–9.
  • Schöffl, V., Lutter, C., Woollings, K., & Schöffl, I. (2018). Pediatric and adolescent injury in rock climbing. Research in Sports Medicine, 26(1), 91–113.

Wednesday, April 18, 2018

Abstract of my article studying the effect on finger endurance of Max Hangs vs. Int Hangs vs. a combination.

Versión en español

As I advanced a couple of days ago through social media, I'm happy to announce that past January one of my latest research articles was accepted for publication in The Journal of Human Kinetics, a peer-reviewed, open-access journal. This means you'll be able to read the paper without the need to pay for a subscription or a fee.

Pending the assignment of a DOI (digital object identifier), when the full text paper will be available, here is the abstract, as a little teaser. It is important to remember that, though the abstract gives you a general overview of the contents, it is advisable to read the full text when it is available. By doing so you’ll get all the nuance that will help you understand the methodology and judge the results in the context of its particular experimental design in order to arrive to your own conclusions and eventually extract something useful for your training.

So, without further ado, here it is, brief but intense. Hoping you’ll be eager for more, enjoy it!

“Comparison of the Effects of Three Hangboard Strength and Endurance Training Programs on Grip Endurance in Sport Climbers”

Note. This article has been accepted for print in a forthcoming issue of the Journal of Human Kinetics. The full text shall appear in the InPress section in the upcoming weeks; then the DOI will be assigned and the whole manuscript will be available online in the journal website. The abstract appears here in its accepted, peer-reviewed form, as it was provided by the submitting author.

Article title: “Comparison of the Effects of Three Hangboard Strength and Endurance Training Programs on Grip Endurance in Sport Climbers”

Authors: Eva López-Rivera1; Juan José González-Badillo2

Affiliations: 1 Faculty of Sport Sciences, Castilla La-Mancha University, Toledo, Spain. 2 Faculty of Sport Sciences, Pablo de Olavide University, Seville, Spain.

Journal: Journal of Human Kinetics.

Acceptance date: 31 January 2018.


Intermittent isometric endurance of the forearm flexors is a determinant factor of sport climbing performance. However, little is known about the best method to improve grip endurance in sport climbing regarding maximal or intermittent dead-hang training methods. The aim of this study was to compare the effects of three 8-week finger training programs using dead-hangs (maximal, intermittent, and a combination) on grip endurance. Twenty-six advanced sport climbers (7c+/8a mean climbing ability) were randomly distributed among three groups: maximal dead-hangs with maximal added weight on an 18 mm edge followed by MaxHangs on minimal edge depth; intermittent dead-hangs using the minimal edge depth, and a combination of both. The grip endurance gains and effect size were 34% and 0.6, respectively, for the group following maximal dead-hang training, 45% and 1, respectively, for the group following intermittent dead-hang training, and 7% and 0.1, respectively, for the group applying the combination of both training methods. Grip endurance increased significantly after 4 weeks in the group performing intermittent dead-hangs (p = 0.004) and after 8 weeks in both groups performing intermittent dead-hangs (p = 0.002) and MaxHangs (p = 0.010). The results suggest that the intermittent dead-hangs training method seems to be more effective for grip endurance development after eight week application in advanced sport-climbers. However, both methods, maximal and intermittent dead-hangs, could be alternated for longer training periods.

Key words: rock climbing, dead-hang training, intermittent isometric training, strength, endurance, climbing performance.

A collage of pictures capturing some moments of my -hard but also enjoyable - researching days with my dear "guinea pigs". Massive thanks, without all of you, this wouldn't have been possible!! Note: The pictures are from 2004 and 2010, excepting that one of my hand, from 2011)


Wednesday, March 14, 2018

Maximal hangs, Intermittent Hangs (Repeaters) or a Combination. Which 8-week program is more effective for developing grip strength in rock climbers?

Versión en español

The previous entry was a first look at the Intermittent dead-hangs training method. There I explained why I chose that name over Repeaters and presented the INTRODUCTION to the first of my studies that compared this method to others, focusing on their effect on finger strength and endurance. This particular work was presented at the III International Rock Congress set up by the IRCRA that took place in Telluride (USA) in 2016. Today, as promised, we will have a more detailed discussion about each aspect of the study:

Goals, Methods, Results, Discussion and Practical Applications

You have the full text of the article in this link; so, instead of reproducing it here verbatim I will explain and elaborate every part except for the introduction, that we have already covered in the previous post. As you might know, the length of a text to be presented in a congress has a limit, just 2 pages in this case.
Beginning the presentation of my study:“Comparison of the Effects of Three Hangboard Training Programs on Maximal Finger Strength in Rock Climbers” at Telluride (Colorado, USA), III IRCRA congress

Comparing the effects on maximal grip strength of an 8-week Maximal Dead-hangs training program (MAXHANGS_MAXHANGS) with an Intermittent Dead-hangs one (INTHANGS_INTHANGS) and a third that combined Maximal and Intermittent Dead-hangs (MAXHANGS_INTHANGS).

The device chosen to perform the training and the tests was the one described in López-Rivera and González-Badillo (2012), and consisted on and edge that could be adjusted in depth with a precision of millimeters (Dimensions 500x250x24 mm; by Eva López and Dafnis Fernández, 2004; Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License).

After being informed in writing about the objectives, characteristics and risks of the study, 26 rock climbers (23 male, 3 female) with and average redpoint level in the past 6 months of 7c+/8a (min 7a, max 9a), 31.7 years of age and 11.7 years of climbing experience were selected under the following criteria:

a) more than 2 years of climbing experience.
b) being active in the sport during the previous 6 months.
c) not having trained dead-hangs for the past 4 months.
d) having a redpoint level of at least 7a.
e) being more than 25 years old.
f) not suffering from an injury or condition that made inadvisable to follow an intensive physical training.

The participants signed their consent and were asked not to change their daily habits or engage in any additional physical activity other than the one prescribed for the duration of the intervention.

Strength Test (ST)
This was the one proposed by the aforementioned authors, which had already validated it by observing the significant positive correlation between the test results and redpoint level (r = 0.51; p < 0.001). The ST took place before starting the intervention, in week 5 after the first four weeks of training and in week 9, after the eighth week of training (see figure below). Data collection was carried out at the Club Vertical climbing facility (Toledo, Spain).

The training session 48 hours before the test was light, and 24 hours prior to the test no sport activity was allowed. Each participant knew the conditions and rules of the test and had learned the right dead-hangs technique. The successive tests were conducted the same day of the week, at the same time and in similar conditions of temperature and air moisture. The warm-up before the test was a 15-minute standardized routine that included neck, shoulders arms, wrists, fingers, upper body, hip and legs mobilization; a specific part of 3-5 dead-hangs followed, decreasing edge depth (20-15 mm according to sport level) and increasing hanging time (10-20 seconds), with pauses 2-3 minutes long. A 5-minute rest was observed before the test itself, during which weight and height were measured. Then the ST was conducted.

A 15 mm edge was chosen for ST, using the half-crimp grip, with extended elbows and the maximum added weight that could be held for 5 seconds. The load was determined as follows: the first try an added weight was chosen that would allow the participant to hang for 15-20 seconds. Then, with 5-minute intervals, 5 to 10 kg were added taking into account the previous try’s perceived intensity. The goal was to reach the maximum load in five tries at most, to prevent the effects of fatigue. When the participant could not keep contact of all fingers with the edge, flexed their arms or modified the angle of the shoulders or the hip with the torso before the 5-second mark, the test was finished and load for the last valid try was recorded.

Among all possible grip types, the half-crimp was chosen because it is the most used on small holds (Bollen, 1988; Schweizer, 2001, Quaine & Vigouroux, 2004, Watts, 2004), small hold size being characteristic of the hardest sections in difficult routes (Quaine & Vigouroux, 2004, Watts, 2004), along with shape and texture. Lastly, dead-hangs were selected due to several authors considering it a climbing-specific exercise (Vigouroux et col., 2006; Watts et col., 2008), and it being a popular one among climbers.
Michaela Kiersch training at the First Ascent Avondale climbing gym (Chicago, USA). Picture: Musenpet.  Source: Facebook

Experimental Design
Based on the results of the first ST the participants were randomly assigned to one of three training groups using the ABCCBA method:

1- MaxHangs_MaxHangs: this group did in the first four weeks of training 3 to 5 sets of 10-second dead-hangs on an 18-mm edge with added weight (named as MAW = maximal added weight at the infographic at the bottom). The weight should allow the athlete to hang for 13 seconds, which implies a 3-second margin (effort level = 3; term proposed by González-Badillo & Gorostiaga in 1993). The pause between sets was 3 minutes. During the next 4 weeks,  the progression in number of sets,  hanging time, effort margin and pause were the same; the difference was that no added weight was used: the load was adjusted by choosing the smallest (less deep) edge (named as MED = Minimal edge, at the infographic at the bottom) that would allow to hang for 13 seconds.

Warming-up was specific to these methods, doing 3-4 sets with increasing added weight or decreasing edge depth (50-90% of previous session’s load). There was a need to determine the load for the first set of the first day of training: the climber would estimate an added weight or edge depth that would permit a 13-second repetition. If this repetition was perceived as too difficult or too easy for the session, some weight (2-5 kg depending on body weight) or edge depth (1-2 mm) was added or subtracted to keep the load constant. This procedure was iterated in each set. For context, the strongest athlete used 55 kg / 5 mm, the less strong 5kg / 10 mm.
Presenting at Telluride. Thanks to Kaycee Joubert, from Real Life Photographs for taking this picture and to Shauna Coxsey por giving permission to use hers!

2- IntHangs_IntHangs: the Intermittent method in the first 4 weeks consisted of 3-5 sets of 4 repetitions, each repetition being a 10-second dead-hang; the pause was 5 seconds between repetitions and 1 minute between sets. No added weight was used, the load was managed by choosing the smallest edge (MED) that would allow to complete all the prescribed volume and reach failure or close to failure in the last repetition of the last set. The second 4-week segment the number of repetitions per set went from 4 to 5.

For this method a different warming-up procedure was followed: 4-5 10-second sets, with a 5-second pause and decreasing edge size; the edge for the first set should have allowed the climber to hang for one minute, which amounted to 5-10 mm deeper than the training edge from the last session. For the first set of the first training session the initial training edge was deep enough to hang for up to 30 seconds.

Load training management was analogue to the MaxHang method: if the participant  estimated that the current edge was going to be too easy or too hard to complete the volume close to failure, he or she would change to a smaller or bigger one. For reference, the smallest edge used with this method was 8 mm, the deepest, 22 mm.

3- MaxHangs_IntHangs: This group combined both methods. The first 4 weeks they trained with added weight like group 1 (MAW); the following 4 weeks, 3 to 5 sets of 4 repetitions of 10-second dead-hangs with the same parameters as group 2. The intensity was adjusted as has already been described.
Across all methods the hanging time was 10 seconds, the number of sets 3 to 5. Every athlete had to manage the training load dynamically throughout the session by choosing a different added weight or edge depth to keep the relative intensity constant.

This said, there was a difference in total volume among methods, because MaxHangs amounted to 30 to 50 seconds per workout while total hanging time in IntHangs was 120 to 250 seconds.
Furthermore, the Max methods avoided failure by prescribing a 3-second margin, while IntHangs actively aimed for failure at the end.

The rationale behind the 10-second hanging duration, and for the 10 to 5 work/pause ratio respectively can be found in the previous blog post.

Training Program
Dead-hang programs
The set/reps configuration, hanging time and pause duration for each group can be found in this figure:

Physical-technical training
It is worth noting that the athletes did not reduce their workout to dead-hangs only; these were instead integrated into a weekly plan as it would be the case in real life. Therefore, there were conditioning and climbing contents carried out in the climbing gym. The whole of the training schedule was an 8-week standardized cycle (ATR-model, block periodization approach; edited on 20 March 2018), adapted to each person, that included all contents. This plan was built and supervised by Eva López.

Dead-hang workouts were done on Mondays and Wednesdays, after the mentioned standard warm-up. A 15-minute recovery would follow and then the other contents for the day according to the mesocycle: physical conditioning like maximal and sub-maximal pull-ups, core; as well as extensive or intensive interval, repetition or projecting methods on boulders and routes, no name but a few.

Gym work happened Monday to Thursday, the weekend was devoted to rock climbing. The participants were instructed to do 1-2 routes for warming-up and 1-2 close to their maximum level. All of this was checked via daily feedback shared by the climbers.
Eva López. Club Vertical climbing facility (Toledo). Photo: Javipec

Descriptive statistics (averages, standard deviations) were obtained for age, years of training, height, weight, sport level in the last 6 months and ST results. A repeated measures ANOVA with Bonferroni correction was applied to assess the intra- and inter-group differences in strength. Pearson’s correlation was computed to look at the relations between variables as well as the effect size (ES) to check for intra-group changes (Hedges & Olkin, 1985). An ES < 0.25 was defined as moderate and > 1 as big in line with the scale proposed by Rhea (2004) for strength training interventions with highly trained athletes.

The differences among groups in ST were not significant, either before and after 4 and 8 weeks of training. However, it is worth noting the 28% of improvement in ST after 8 weeks experienced by the MaxHang_MaxHang group, as well as that the strength gains only reached statistical significance in this group and not in the others; and the better outcome after 4 weeks of the groups  that did MaxHangs with added weight (15% and 20%) in contrast with the IntHangs group (4.6%).

The second interesting result was the relatively small change in strength by IntHangs_IntHangs after 4 weeks (4.6%) that tripled at the end of the 8th week (13.9%), a result comparable with what MaxHangs achieved in the first 4 weeks.

Finally, the group that changed from MaxHangs to IntHangs in the 5th week lost almost 7% of the gains developed during the MaxHangs mesocycle.
Results by group in the strength test (maximal added weight hold for 5 seconds off a 15 mm edge, half-crimp grip) after 4 and 8 weeks of training. Source:
To the extent of our knowledge this is the first work to compare the effects on grip strength of a MaxHangs program, an IntHangs program and a combination of both in experienced sport climbers  (7c+/8a average level, 12 years of experience). The most effective program after 4 and 8 weeks of training was MaxHangs_MaxHangs, which was also the only one to show significant change in ST3 (p < 0.05).

The early gains yielded by MaxHangs after 4 weeks with added weight can be attributed to neural changes (Hakkinen & Komi, 1985a; Hakkinen et col., 1998; Sale et col., 1998) and are comparable to the 15-18% observed after 4 to 6 weeks of a similar isometric training (3 to 10-second sets, >80% MVC, complete recovery) by Ikai & Fukunaga (1970), Cannon & Cafarelli (1987) and Davies et col. (1988) with untrained subjects. Also in this line Judge et col. (2003) reported maximal isometric force going up by 15% in throwers after gradually increasing volume and intensity during a 16-week period, in this case through dynamic exercises.

We are not aware of other studies that assessed the effects of a static training with loads on trained athletes, as is the case of this one. On the other hand there are several examples of dynamic exercises producing strength improvements in athletes by the use of loads. Hickson et col. (1988) found a 30% significant change in 1 RM in cyclists that underwent a 10-week cycle doing 3x5 RM strength exercises. The fact that this figure is higher than the one registered by us could be explained by the longer duration of the intervention, or by the participants lacking experience with lower body strength training while having a well-developed specific endurance; the authors do not mention whether this is the case or not.

The only work we have found where a 4 week dead-hangs program is carried out, by Medernach et al. (2015), included a group of boulderers who significantly improved their time to fatigue with the maximum added weight corresponding to an initial hanging test for 6 seconds off a 19 mm edge, by contrast with the group that only did bouldering, with significant but more modest gains (12.5± 2.5 seconds, 8.6 ± 2.0 seconds respectively). However, these results can’t be compared with ours, having a different test and intervention design, mainly because instead of setting different dead-hangs methods side to side it compared a control group with another that did 1 session of MaxHangs and 2 of IntHangs each week; additionally, the dead-hangs programs included pull-ups and lock-offs.

Effects of intermittent dead-hangs after 4 weeks

The IntHangs group improved their strength just 4.6% at ST2. One reason can be not using added weight, or that the intensity was lower than in the other groups; these factors have been shown to be related with maximal strength going up in experienced athletes like the ones in this study (Hakkinen, 1994; Tan, 1999; Fry, 2004; Peterson, Rhea & Alvar, 2005). The lower intensity results from the incomplete character of the recovery pauses (5 seconds between repetitions, 1 minute between sets) as well as from the higher resulting TUT (time under tension) (Rhea et col., 2003; Watts et col., 2004; Mirzaei et col. 2008), that make it unfeasible to maintain a high absolute load during the session. Our estimate is that the relative intensity was 70-80%, corresponding to 30 seconds of maximal hanging time, compared to the 90% which could be associated to the 13 seconds of MaxHangs.

The MaxHang group confirmed the trend after the first training phase and ended up ahead of the others in ST3, after 8 weeks of training (28% up, compared to 13.9% IntHangs_IntHangs and 13.4% MaxHangs_IntHangs). Added weight probably played a role in this respect, causing greater muscle activation and recruitment of motor units (Hakkinen et col., 1985a and 1985b; Sale, 1988; Harris, 2000), which in turn made possible to use smaller edges during the last four weeks resulting in sustained strength gains.

This 28% change in 8 weeks is lower than the 35% improvement in MVC obtained by Jones & Rutherford (1987) with isometric training, doing 4 x 6 repetitions at 80% of MVC, 4 seconds per repetition and 2 seconds between repetitions for 12 weeks. Rich & Cafarelli (2002) registered also a notable 35% change in MVC in 8 weeks doing 5 x10 maximal contractions, 3 to 5 seconds in duration each. These figures could be attributed to the workouts being prescribed to persons lacking strength training experience, where greater development is to be expected.

As far as we know there are no studies looking at experienced athletes doing static training for more than 4 weeks. However, gains similar to the ones shown in this study, 20 to 30%,  have been reported in dynamic tests with participants familiar with strength training (Hakkinen et col., 1985b), trained cyclists (Rønnestad et col., 2010) or competitive swimmers (Tanaka et col., 1993) who performed dynamic training, 1 to 10 RM for 10 weeks.

The better outcome in strength of the group that worked their strength first with added weight and then without it (MaxHang_MaxHang) compared to the other two groups is consistent with the findings of our previous study (López-Rivera & González-Badillo, 2012), where this sequence of exercises also showed a greater effect on strength than the opposite, starting with the minimal edge depth exercise and following with added weight. It is worth noting that this earlier work yielded a 1.34% improvement in strength (for 28% of the current one), a difference which may result from the disparity in level between samples (8a average, 7a min., 9a max. 11.1 years of practice versus 8a+/b average, 8a min., 8c+ max and 16 years of experience in the earlier work). As suggested by authors like Hakkinen et col. (1987) or Peterson, Rhea & Alvar (2004), the expected change after a given training gets smaller as sport level and experience go up. Stronger athletes familiar with strength training show a smaller adaptive response and need a higher dose of strength training (Hakkinen et col., 1987).

The second noteworthy result concerns group 2, which used a method generally deemed to promote strength-endurance. Strength going up 4.6% in ST2 did not come as a surprise, but then they achieved a 13.9% change from ST1 to ST3).

The literature offers a possible cause for this good outcome after 8 weeks; doing 4-5 repetitions per set, 10 seconds each repetition amounts to a long TUT; in addition the intensity is sub-maximal and the pause incomplete (5 seconds between repetitions and 1 minute between sets). These characteristics have been hypothesized as promoters of strength by hypertrophy, mainly by adding sarcomeres in parallel rather in series (Kraemer et col., 1990; Hakkinen, 1994; Behm, 1995; Robinson et col., 1995; Fleck & Kraemer, 1997; Hoffman et col., 2003; Goto et col., 2005; Toito & Boutellier, 2006; Ratamess et col., 2007, Willardson, 2007; Miranda et col., 2009) caused by high lactate-induced metabolic stress, hormonal stress, muscle damage and, most importantly, by mechanical tension associated to moderate to high-load training (Hakinnen et col., 1994; Goto et col., 2005; Schoenfeld, 2012), effect becoming more evident after 6-8 weeks of training unlike in the case of the neural adaptations characteristic of the first weeks of training (Hakkinen & Komi, 1985a; Hakkinen et col., 1998; Sale et col., 1998).

The 13.9 difference in strength after 8 weeks of doing 3 - 5 x 4 - 5 x10” :5”/1’ are below the 33% change in MVC after 8 weeks of electrostimulation of the first dorsal interossei of the hand in the form of 4 sets of ten 10-second repetitions with 20 seconds of pause between repetitions and 2 minutes between sets, by Davies et col. (1988). Jones & Rutherford (1987) also recorded a 35% increase in MVC when doing 4 x 6 isometric contractions at 80% MVC, each repetition 4 seconds long, 2-second pauses between repetitions for 12 weeks. Another result that yielded higher figures than ours is Schott et col. (1983), after a 5-week intervention where the participants performed 10 sets of 3-second isometric contractions, with pauses of 2”/1’, and ended up gaining 31%. Lastly, McDonagh et col. (1983) observed a 20% MVC improvement when doing 30 to 50,  3 – 5 seconds long isometric contractions of the elbow flexors, with a recovery duration of 20 seconds, for 5 weeks. All these works used a variety of protocols that differ with ours, but they have in common the participation of persons who lacked experience in strength training, and this may explain part of the differences in outcome. There is one study where an isometric training program was prescribed to trained athletes: Gondin et col. (2005) looked at the effects of 32 18-minute sessions of 40 isometric contractions via electrostimulation of the knee extensors, the change amounting to 6% and 27% after 4 and 8 weeks respectively. While the first 4 weeks the numbers of this study and ours are comparable, the gap widens at the end of the 8th week, probably due to the mentioned work involving a longer TUT than the IntHangs exercise (25 10-second contractions at most); this variable has been advanced as a factor affecting in the magnitude of hypertrophy by some authors (Sale et col., 1985 [in Wemborg et col., 2007]) and its associated strength gains.

We want to underline a last interesting result, the 6% loss in strength by the MaxHangs_IntHangs group (group 3) from the 5th to the 8th week after the positive change observed in the first 4 weeks with added weight. Changing the stimulus to a lighter one could be behind this downturn. Similarly, Rhea et col. (2003) observed an effect size (ES) of negative 0.31 in 1 RM after increasing the number of repetitions every five weeks from 15RM to 20RM and 25RM, and thus diminishing the intensity, compared to a control group where the intensity went up, from 25RM to 20RM and 15RM

 On the other hand, a training method that involves incomplete recovery on small edges is more suitable for improving strength-endurance and is liable to provoke a level of fatigue after 4 weeks that the climbers can’t recover from when the time for ST3 comes, not to mention the implications that can have on the effects of the IntHangs, the fact that this group obtained great strength improvements in ST2. Presumably, being able to train with this tiring method using smaller edges could provoke greater fatigue due to a greater muscle activation (Ahtiainen & Häkkinen, 2009) (Also, the smaller the hold is, the more mechanical tension is needed to grip it effectively, and the more intense  -physical and psychological- the resulting effort is). As Anderson & Kearney (1982) suggest, training-induced fatigue can have different effects depending on the way it is produced. In their work, the participants who did a higher volume (100-150 RM) experienced greater homeostatic perturbations in the muscle.

Lastly we have to keep in mind that individual characteristics like muscle fiber composition (Thorstensson & Karlsson, 1976; Willardson, 2006) or genetic profile (Ginszt et al., 2018) that can lead to a greater fatigability among other consequences, can have a non-trivial effect on training response (as hinted by the large standard deviation recorded in this group) when the sample size is as small as ours and therefore a big impact on final results.

Taking all this into account we would suggest carrying out a follow-up study that extended the program by doing 8 additional weeks of IntHangs.

Summing up, the group that displayed greater strength gains was the one that did 8 weeks of MaxHangs. The IntHangs_IntHangs group experienced little change in the first four weeks but strength went up noticeable after the last four, probably because there was time for hypertrophy to set in. Last, it seems that 4 weeks of MaxHangs and 4 weeks of IntHangs would not be advisable in terms of strength outcome, presumably due to 4 weeks being too short a duration for the second method.

The overall results are indicative that MaxHangs are more suited to develop grip strength in climbing, specially in the short and medium term. Nevertheless, with the sights set on the long-term outcome of trained athletes, we are in a position to suggest that sequentially prescribing MaxHangs and IntHangs methods could be a way to avoid plateauing and get greater changes in strength because the neural development caused by the high loads of MaxHangs would add up to the hypertrophy effects of IntHangs.
Who said people of science are boring? Photo: Real Life Photographs

See you at Chamonix 2018?  Picture: Real Life Photographs
… but don’t leave before this appeal to caution. Please, remember that a single work must not be taken as definitive proof, and that an intervention evaluated through a scientific study can’t be generalized to every kind and level of climbing or repeated in your planning time and again. Training prescription should be always specific to individual goals and abilities (this last sentence was added on 21 March 2018). Furthermore, reading just an abstract and extrapolate it, as well as jumping directly to the conclusions here or the infographic below keeps you from learning the details, 😝 where more often than not resides the nuance that we need to relativize and actually learn). No matter how effective a method is shown to be for a group of people at certain moment in time (be it by your own experience or a controlled, standardized experiment), when dealing with trained athletes the evidence says that periodization (changing parameters, like volume and intensity, according to a previously defined schedule, like the weekly variation in number of sets in this work) and method sequentiation are superior to the alternative, performing the same routine indefinitely (Kraemer et al., 2000; Rhea & Alderman, 2004; Grgic et al., 2017). A quick example would be changing the hanging (exertion) time, or the effort margin in the MaxHangs, as well as the recovery pauses or the hanging time of IntHangs every four weeks…

I’m afraid we have to leave this here, but I encourage you to accompany me in this exploration, and in the next entry we will look at some, more specific training plans that can be effective.

MAW = Maximal Added Weight; MED = Minimal edge.
Clic to enlarge

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