Electromyographical Comparison of Pike Variations Performed With and Without Instability Devices

Snarr, RL, Hallmark, AV, Nickerson, BS, and Esco, MR. Electromyographical comparison of pike variations performed with and without instability devices. J Strength Cond Res 30(12): 3436-3442, 2016-Instability devices are primarily used with the intent of increasing the intensity of traditional exercises by providing further muscular demands of the abdominal wall by decreasing stability. Although there are multiple studies examining these devices, most often they only compare one such device to a stable movement and overlook the comparison among multiple devices. The purpose of this investigation was to compare the electromyographical differences of the rectus abdominis (RA), external oblique (EO), erector spinae (LSES), and rectus femoris (RF) during pike variations performed on various surfaces. Twenty men and women volunteered for this study. All subjects performed 5 variations of a pike on varying surfaces (i.e., stable ground [PK], Swiss ball [SB], suspension training device [ST], BOSU ball [BOSU], and Core Coaster [CC]). Normalized (%MVC) values were recorded for each muscle during 5 repetitions of each pike variations. For the RA, EO, LSES, and RF, the PK elicited significantly lower values compared with the instability devices. In terms of the EO, the ST was significantly higher than the BOSU, SB, and CC. Results of this investigation demonstrated significant differences between the instability devices and the stable pike. These results indicate that with more freely moving instability devices (e.g., suspension device, Swiss ball, etc.), core musculature may require greater muscular demands. Practitioners should take note that traditional stable pikes may not offer a core musculature challenge to resistance-trained individuals.