Lower and upper body isometric strength in climbers: reliability and associations with an assessment of climbing performance

The aims of this study were to: a) investigate reliability of a unilateral maximal isometric finger and pull strength test, isometric mid-thigh pull (IMTP) and intermittent-fatiguing strength test in intermediate (INT) and advanced (ADV) climbers; b) determine the differences in physical test performance and total score of athleticism (TSA) scores between INT and ADV climbers; c) determine the associations between such physical tests and the intermittent-fatiguing strength test. Sixty-nine climbers (INT = 35, ADV = 34) performed the physical tests, with reliability scores ranging from good to excellent (INT: coefficient of variation (CV) = 6.4 to 9.2%, intraclass correlation coefficient (ICC) = 0.81 to 0.94; ADV: CV = 6.1 to 8.4%, ICC = 0.87 to 0.95). Moderate to large differences were observed in favour of the ADV group in each test (g = 0.70 to 1.09; % difference = 5.09 to 203.30%; p < 0.05), including IMTP (g = 0.71; % difference = 14.17%; p < 0.05) and in the composite score (TSA) (g = 0.77; % difference = 203.30%; p < 0.05). There were moderate to strong significant correlations between intermittent-fatiguing strength test and finger strength test (r = 0.69 to 0.71) and IMTP (r = 0.64) in the INT group. In the ADV group, the intermittent-fatiguing strength test was significantly moderately to strongly associated with finger strength test (r = 0.63 to 0.73), pull strength test (r = 0.66 to 0.67), and IMTP (r = 0.73). Thus, performance tests differed between INT and ADV climbers and finger strength moderately to strongly correlates with an intermittent-fatiguing strength test. Our findings suggest climbers' training programs should improve upper limb pulling capacity and finger flexion force outputs.