Estimation of hand and wrist muscle capacities in rock climbers

Abstract

imbalance between flexor and extensor capacities which suggests a potential risk of pathologies. Conclusions The practice of climbing not only increased the strength of climbers but also resulted in specific adaptations among hand muscles. The proposed method and the obtained data could be re-used to optimize the training programs as well as the rehabilitation processes following hand pathologies. Muscle imbalance ratio of the j joint (j = MCP or wrist) Keywords AbstractPurpose This study investigated the hand and wrist muscle capacities among expert rock climbers and compared them with those of non-climbers. The objective was to identify the adaptations resulting from several years of climbing practice. Methods Twelve climbers (nine males and three females) and 13 non-climber males participated in this study. Each subject performed a set of maximal voluntary contractions about the wrist and the metacarpo-phalengeal joints during which net joint moments and electromyographic activities were recorded. From this data set, the muscle capacities of the five main muscle groups of the hand (wrist flexors, wrist extensors, finger flexors, finger extensors and intrinsic muscles) were estimated using a biomechanical model. This process consisted in adjusting the physiological crosssectional area (PCSA) and the maximal muscle stress value from an initial generic model. Results Results obtained from the model provided several new pieces of information compared to the analysis of only the net joint moments. Particularly, the capacities of the climbers were 37.1 % higher for finger flexors compared to non-climbers and were similar for finger extensor and for the other muscle groups. Climbers thus presented a greaterCommunicated by Nicolas Place.

Performing pull-ups with small climbing holds influences grip and biomechanical arm action

“…For FE and FF muscles, the electrodes were positioned as described in Vigouroux, Goislard de Monsabert, and Berton (2015). Special attention was paid to minimize cross-talk with the nearby wrist flexors and extensors.…”

“…Nevertheless, these values were estimated using large climbing holds while during training and climbing, climbers mainly use small holds. Concerning the climbers' finger and forearm muscle capabilities, several previous studies revealed that climbers have high capacities for exerting maximal forces at the fingertips (Cutts & Bollen, 1993;Quaine et al, 2003;Vigouroux, Goislard de Monsabert & Berton, 2015) and minimizing fatigue effects during intermittent repetition of intense finger-grip forces (80% of maximal voluntary force, MVF) (Philippe, Wegst, Müller, Raschner, & Burtscher, 2012;Quaine et al, 2003;Usaj, 2002;Vigouroux & Quaine, 2006). Additional studies emphasised the importance of the hold depth for generating intense finger force and, by way of consequences, for climbing performances (Amca, Vigouroux, Aritan, & Berton, 2012;Bourne, Halaki, Vanwanseele, & Clarke, 2011).…”

Assessment of the risk and biomechanical consequences of lateral epicondylalgia by estimating wrist and finger muscle capacities in tennis players

“…A method previously used to investigate muscle capacities in rock-climbers (Vigouroux et al, 2015) has been adapted for this study. A hand-wrist ergometer (Bio2 M, Compiegne, France) measured the net isometric flexion and extension moments about the wrist and the MCP joints at 2000 Hz ( Figure 1A).…”

“…Surface electrodes (9-mm diameter) were positioned over the muscle bellies after skin abrasion and cleaning with alcohol. Electrodes were placed as in Vigouroux et al, (2015) and their placement was checked by asking participants to execute a series of contractions targeting specific flexor or extensor muscle groups about either the wrist or the MCP joints. EMG signals were filtered using a Butterworth filter (bandpass, 4th order, zero phase lag, bandwidth 20-400 Hz).…”

“…Because co-contraction is inevitable, maximum isometric net joint moments always include the conjoint actions of both agonist and antagonist muscle groups, and might therefore inadequately represent agonist muscle capacity (Amarantini & Martin, 2004). In order to improve the assessment of muscle capacity, methods have been developed to estimate the individual contributions of agonist and antagonist muscle groups using a combination of net joint moments and EMG signals as inputs for musculoskeletal models (Amarantini & Martin, 2004;Olney & Winter, 1985;Rao et al, 2009;Vigouroux, Goislard de Monsabert, & Berton, 2015). The use of such methods might therefore be more appropriate for investigating muscle capacity ratio with regard to the occurrence of lateral epicondylalgia.…”