Molecular Adaptations to Concurrent Strength and Endurance Training

Abstract

Several investigators have demonstrated that chronic eccentric leg cycling is an effective method for improving lower body neuromuscular function (e.g., quadriceps muscle size, strength, and mobility) in a variety of patient and athletic populations. To date, there are no reports of using eccentric arm cycling (EC(arm)) as an exercise modality, probably in large part because of the lack of commercially available EC(arm) ergometers. PURPOSE: Our purposes for conducting this study were to 1) describe the design and construction of an EC(arm) ergometer and 2) compare EC(arm) to traditional concentric arm cycling (CC(arm)). METHODS: All of the parts of a Monark 891E cycle ergometer (Monark Exercise AB, Vansbro, Sweden) were removed, leaving the frame and flywheel. An electric motor (2.2 kW) was connected to the flywheel via a pulley and a belt. Motor speed and pedaling rate were controlled by a variable frequency drive. A power meter quantified power and pedaling rate, and provided feedback to the individual. Eight individuals performed 3-min EC(arm) and CC(arm) trials at 40, 80, and 120 W (60 rpm) while VO(2) was measured. RESULTS: The EC(arm) ergometer was simple to use, was adjustable, provided feedback on power output to the user, and allowed for a range of eccentric powers. VO(2) during EC(arm) was substantially lower compared with CC(arm) (P < 0.001). At similar VO(2) (0.97 ± 0.18 vs 0.91 ± 0.09 L·min(-1), for EC(arm) and CC(arm), respectively, P = 0.26), power absorbed during EC(arm) was approximately threefold greater than that produced during CC(arm) (118 ± 1 vs 40 ± 1 W, P < 0.001). CONCLUSION: This novel EC(arm) ergometer can be used to perform repetitive, high-force, multijoint, eccentric actions with the upper body at a low level of metabolic demand and may allow researchers and clinicians to use EC(arm) as a training and rehabilitation modality.