
Dumbbell carrying position and muscle activity
The following study investigated the differences in kinematics and muscle activity of various lower limb muscles between different dumbbell carrying positions during walking lunges (WL) and split squats (SSq). Contralateral WL highly activated Gmed (90%MVIC) – therefore, this exercise may be beneficial for optimising Gmed maximal strength. Conversely, ipsilateral loading did not have the same effect.
Exercise selection is a key point when designing a resistance training program. Not only do some exercises target certain muscle groups over others, but the activation of a specific muscle group can be altered by performing variations of the same exercises. The forward WL and SSq are similar exercises that have differences in the eccentric phase, and both can be performed in the ipsilateral or contralateral carrying positions. The aim of the following study was to determine the effects of dumbbell carrying position on the kinematics and electromyography (EMG) amplitudes of gluteus medius (Gmed), vastus medialis (VM), vastus lateralis (VL) and biceps femoris (BF) during WL and SSq.
28 participants were split into a resistance-trained (RT) and non-resistance-trained (NRT) groups. Differences between both groups were noted – the NT group had a smaller knee flexion ROM during both types of WL, whereas the RT group demonstrated higher eccentric Gmed amplitude during all exercises. Both groups also exhibited differences in contralateral and ipsilateral WL.
These findings suggest that SSq should be performed during the initial phase of a resistance training program before WL, to ensure that participants achieve full ROM and moderate Gmed activity during this exercise.
> From: Stastny et al., J Strength Cond Res (2015) (Epub ahead of print). All rights reserved to Lippincott Williams & Wilkins. Click here for the Pubmed summary.
