Comparative Analysis of Elbow Flexor Morphology, Physiology, and Performance Between Arm Wrestlers and Strength-Trained Athletes

Coletta, F, Cesanelli, L, Kamandulis, S, and Conte, D. Comparative analysis of elbow flexor morphology, physiology, and performance between arm wrestlers and strength-trained athletes. J Strength Cond Res 39(5): 579-586, 2025 - This study aims to compare the morphological, performance, and physiological characteristics of the elbow flexors between arm wrestlers and strength-trained athletes. Nine national and international level arm wrestlers (age = 30.5 ± 7.7 years, body mass = 89.4 ± 7.5 kg, stature = 183 ± 7.3 cm, strength training experience = 12.7 ± 8.6 years, arm wrestling training experience = 4.8 ± 2 years) and 9 strength-trained athletes (age = 28.6 ± 4.6 years, body mass = 88.2 ± 15.4 kg, stature = 179.4 ± 5.8 cm, strength training experience = 11.3 ± 8 years) voluntarily participated in the study. Arm and forearm circumferences of the dominant upper limb were measured to assess the anthropometric characteristics. Moreover, morphological evaluations of the biceps brachii muscle and distal tendon thickness were conducted using ultrasound. Peak torque (PT) and rate of force development (RFD) were assessed using 2 elbow flexion maximally voluntary isometric contraction tests (test-1: 3 × 3 seconds; test-2: 3 × 20 seconds). During test-2, biceps brachii oxygenation levels were measured using near-infrared spectroscopy. Arm wrestlers exhibited greater forearm hypertrophy compared with strength-trained athletes (p = 0.005; effect size [ES] = 1.54; large), whereas no differences (p > 0.05) were found in arm circumference and biceps brachii muscle and tendon thickness (normalized by muscle thickness). In addition, arm wrestlers showed higher PT in both tests (p < 0.05; ES = moderate-to-large) and higher RFD only in test-1 (p < 0.005). Finally, a greater reduction in muscle oxygenation levels (p = 0.025; ES = 0.277; moderate) was found compared with strength-trained athletes. This study provides insights of the arm wrestlers' physiological and performance characteristics allowing coaches to design appropriate training sessions in this unique sport.