The main objective of the maximum finger strength workouts is to improve your ability to grip the holds with your hands. This ability has been observed as closely related to maximum finger strength (1) and is considered to be the most determinant for climbing performance (2), all the others being dependent on it (3). These workouts are based on sustained efforts with weight overload, a methodology that has been traditionally used in strength training (4), and that shows positive effects on different level climbers when applied to finger hangs (5). Studies on strength training indicate that the effects achieved through them depend mostly on the relative intensity that is used (6,7), but also on how many repetitions are performed (8), both conditioned by the previous training experience (9-11). The different training levels you can find in the pre-configured maximum strength workouts of this App progress in difficulty (or load) by setting higher relative intensities and effort margins (EM), but maintaining the overall duration of the finger hangs. The use of the EM, defined as the difference between the effort that is actually done and the maximum effort that could be done (12), has also been considered in these workouts since making efforts that do not end in muscular failure has been proven safer and equally effective than making them until muscle failure, to improve strength and boost its long-term adaptation (13). On the other hand, the methodology of sustained isometric efforts, when compared with the use of intermittent efforts, has achieved greater effects on the maximum strength even for an equal time under tension and equal relative intensity (14). In this sense, the rest time in these workouts, going from 2′ to 3′ between hangs, has been considered enough to maintain the quality of the efforts (15), which should allow you to keep the same effort margin (EM) within the proposed range of repetitions for each training level (13). In any case, the indications offered about the right moment to end a workout, guarantee this. In addition, this effort vs rest proportion has shown to have a greater hypertrophy effect than that obtained using shorter rest times, like in the cluster type methodology (16) applied, for example, in the workouts based on intermittent hang exercises. The purpose of all this is to let you achieve a long-term positive adaptation effect on strength (17).


The main objective of the grip power workouts is to improve your ability to exert force with your finger flexors at a higher speed, allowing you to achieve quicker an effective grip on any handhold. This ability of the finger flexors to contract in a few tenths of a second, measured through the rate of force development (RFD), has been related to climbing performance (18), especially in bouldering (19) where the typical movements, in general, require that enough force is exerted by muscles within a very limited lapse of time to grip the holds (20). Nonetheless, this ability seems equally important in the most difficult climbing routes, where there are more and longer high intensity sections. Therefore, the higher the level of a sport climber is, the more this ability may specifically preponderant be in him. The grip power workouts are based on performing very short one-handed finger hangs, at a very high intensity. This methodology, that has shown to achieve significant improvements at the level of the maximum strength and the RFD in climbers(21), is similar to that used in the intermittent finger hang workouts based on cluster training (22). But in this case, as the intensities are set (proportionally) higher and the rest time between repetitions is set longer than in the intermittent workouts that improve endurance, the density is quite lower. Anyway, the key element to keep in mind in regard to maintaining the quality of the work during a grip power workout is the EM (12), which you should always observe. This is explained in the internal dynamic of these workouts. All these characteristics of the grip power workouts will allow you to maintain the same quality or intensity in each repetition of every set (13), which is essential in this kind of training, since exercises performed at such high intensities have been associated with some adaptations at the nervous level (7,23) such as an increased amplitude of the nerve signals (24), the acceleration of their activation/relaxation ratio (25), higher triggering frequencies (26), and improvements in the nervous conduction model (27). All these adaptations improve the exertion of high levels of force at a very high speed, which is the main objective of this kind of workouts. The reason behind performing one-handed hangs is the use of larger holds compared to those that should be used on two-handed hangs with the same relative intensity. This is done for safety since using larger holds is less stressful for the soft tissues of the hands and fingers, since smaller lever arms are generated between the tendons and pulleys (28-30). In this sense, the grip positions are selected for each pre-configured workout taking this criterion, among others, into account. On the lower levels the prevailing positions are the open grips. Finally, although this hasn’t been specifically studied, the instability that one-handed hangs can generate on the grip, may potentiate the objective of this kind of workout since in a study where climbers performed finger hangs with added vibration (31), a greater effect on the finger strength was observed compared with the results of a similar training carried out without vibration.


The objective of the aerobic/anaerobic endurance workouts is to potentiate some of the adaptations improving your ability to recover more quickly from local efforts of high intensity. This will allow you to increase the time you can endure climbing (32), and, partly, to recover faster in the rest spots or in the sections with a lower intensity (33). All this has been related to the performance in climbing (34,35). The methodology used in these workouts is based on intermittent efforts of high-intensity (36), also known as clusters (22), consisting in performing as many sets as possible on which that intensity of specific effort can be maintained (15). The goal of these workouts is to improve your ability to tolerate high intensities, which has been associated with better recovery processes (13), and the potential to develop higher effort intensities, which dependents particularly on certain neural adaptations related to maximum and explosive strength (26). The methodology in these workouts has shown a positive effect on the increase of oxygenation between efforts (37) allowing a greater creatine re-phosphorylation (38). Increased local phosphocreatine reserves mean a greater ability to maintain high intensity isometric efforts, which has been associated with better climbing performance (32,33,39,40). Although the intensity isn’t specifically set in these workouts, it will probably fall above the occlusion threshold, (since they intrinsically require it to be high), therefore the chances that the phases of effort/contraction may be done without local presence of blood flow are high. As a consequence of this, the only time when oxygen from blood may with certainty be available for the finger flexors is during the rest phases between contractions (repetitions), which is a key parameter in this kind of workouts. The duration of these rest times progressively decreases as the level of the pre-configured workouts increases, having a minimum value of 3″. This limit responds to the observation of very depressed oxygenation dynamic for lower recovery times (41), which would not allow to achieve the intended training objective.


The objective of the anaerobic endurance workouts is to improve your ability to endure the local effort required by the most intense climbing sequences, which means improving your ability to manifest this type of endurance in the finger flexors. These sequences are typical of the most difficult sections of any climbing route or boulder (42), so they condition the activity’s performance (40). The methodology used in these workouts is based on intermittent efforts done at an intensity corresponding to the individual local occlusion threshold (OT), and with very short rest times (less than 3″). As shown by previous studies, this dynamic makes the active muscle’s re-oxygenation during the rest periods extremely difficult since the available time for the reactivation of the local blood flow between contractions is very limited (41). During the contraction phase, re-oxygenation is impossible since blood flow is nonexistent at the OT work intensity. This produces a maximum post-contraction reactive hyperemia since, at the end of each contraction, the lack of blood flow propitiates that the incoming blood reach the highest possible circulation speed in the vessels of the muscles that have been activated at that intensity (43). This phenomenon induces a maximum shear force (or friction) on these vessels, which is the best stimulus for arteriogenesis (thickening of the walls of the local vascular tree) (44). There is evidence showing that this structural adaptation favours recovery between contractions (45), which added to other adaptations associated with the central (46) and local flow control (47) predispose to deal better with the ischemic situations (absence of blood flow) commonly found in climbing, particularly during the most difficult sections (32) when the finger flexors are probably contracted at an equal or higher intensity than the OT. The anaerobic endurance workouts could induce the strongest adaptations in this sense, since the intensity at which they are performed, the OT, is the lowest allowing to achieve an intermittent total ischemia, and is therefore, the one allowing the highest workout volume that is possible under these conditions that ensure a maximum training effect. The objective of these workouts in the long term is to encourage the existence of some blood flow at effort intensities where before none existed, which could improve your climbing performance since the lack of it has been evidenced as the major limiter for the duration of isometric contractions (48-52), and precisely, in this activity, the finger flexors work  isometrically. To finish, as the level of these pre-configured workouts progresses, their effort/rest ratios (ERR) will become more and more specific, with an increasing disproportion between the effort and rest times, making the work done at the local level more similar to what happens in the most difficult parts of a climbing route (20). This greater imbalance between the effort and rest times is an added criterion of difficulty (53) that could have an added positive effect to improve your specific endurance (54), since longer contraction times imply a deeper de-oxygenation (55), and consequently, a higher involvement of the anaerobic component of endurance (56).


The objective of the aerobic endurance workouts is to boost the basic adaptations that propitiate your ability to recover quickly when progressing through sections of moderate difficulty, and in the rest spots (33), which has been related to the performance in climbing (34,35). However, the evidence shows that in terms of performance the ability to climb more intense sections is more important than being able to climb less difficult sections for a longer time (42). This would be in accordance with previous studies (57) suggesting a greater development, in higher level climbers, of the finger flexors’ type IIA fibers, which would be those responsible of sustaining for a longer time the high intensity intermittent efforts, meaning they would determine passing succesfully the hardest parts of a route. However, the work capability of the finger flexors on lower intensities, which depends on the oxidative capacity of their slow-twitch fibers (type I or ST), has also been related to performance (35). In fact, improving the oxidative potential of these fibers (type I) would propitiate a faster recovery during the rest phase since it would intervene in the restoration of the local ionic balance after a phase of intense effort, which would indeed determine performance (42). In other words, when climbing the hardest parts of a route, most of the energy used to sustain the contractions is produced under anaerobic conditions (58,59) since the oxygen available inside the muscle fibers is depleted, and at that intensity the blood flow becomes scarce or nonexistent (32). This makes the intracellular environment to acidify,  progressively hindering the muscular contractions, until the molecules (H+) causing this can be neutralised inside the muscle fiber itself, or until the contraction is ended. But these molecules are not only buffered inside the fiber that produces them: some are dragged by the blood to be metabolised somewhere else in the body, and some are absorbed and used by the surrounding oxidative fibers (ST) to produce more energy. Therefore, it seems that having a dense capillary bed, which is something quite trainable and characteristic in climbers (45,60,61), as well as having an improved oxidative capacity (34,39) at the level of the slow-twitch fibers in the finger flexors, would be beneficial for these processes. This means that these adaptations would not by themselves be enough to go through the most intense sections of a climb, but they would create good conditions for the fast-twitch fibers to perform better. The methodology behind the aerobic endurance workouts is based on low intensity intermittent efforts with long rest times (5”) between contractions, allowing to generate a stimulus from a high volume load of intermittent-isometric efforts, with a permanent presence of local blood flow. In particular:

  1. the work intensity is 25% lower than the OT for two reasons:
    1. to ensure a certain blood flow tension during the contraction phases, which will certainly occur by working well below the OT, allowing a constant provision of oxygen to the involved fibers (type I, mostly) and to achieve the wanted stimulus in the target tissue, propitiating the creation of new blood vessels (angiogenesis) inside it.
    1. to work at an intensity that is probably near to the critical force (CF). This intensity has been shown as the highest at which an intermittent effort can be sustained for a long time (62), so also the highest at which a high volume load can be beard without reaching muscle failure. The studies carried out so far in climbers place the average intensity of the OT at 65,6% of the maximum strength (63) and that of the CF at 41% (62), which explains the 25% difference used.
  2. the rest time between contractions is always 5” to ensure a full recovery (or almost), through the aerobic metabolism, of the energy that have been used, since previous studies (41) have shown that the complete restoration of the blood flow during the rest times would allow this.


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Example of a maximum strength workout

More on the internal dynamic of the maximum strength workouts

Example of a grip power workout

More on the internal dynamic of the grip power workouts

Example of aerobic/anaerobic endurance workout

More on the internal dynamic of the aerobic/anaerobic endurance workouts

Example of anaerobic endurance workout

More on the internal dynamic of the anaerobic endurance workouts

Example of aerobic endurance workout

More on the internal dynamic of the aerobic endurance workouts