The effects of sex and load on quantifying the bilateral force deficit during an upper body Wingate test

Abstract

Introduction: The bilateral deficit (BLD) is a reduction in the amount of force during a bilateral task vs. the total force from the unilateral limbs performing the same task. We quantified the BLD during an upper body Wingate Anaerobic Test (WAnT) and evaluated the influence of sex and load on the BLD in force.

Methods: Eighteen participants performed maximum handgrip strength, voluntary isometric contractions (MVIC), and three 30s WAnTs. In each session they completed the tasks with the dominant-arm, non-dominant arm and with both arms, randomly. WAnT intensities were 3, 4, and 5% body weight (BW). Instantaneous force data was used to calculate the BLD.

Results: Males showed greater (p < .001) BLD of force at 3, 4, and 5% BW than females by -17, -27.6 and -36%, respectively and had a greater (p < .001) BLD of force than females throughout time points 1-10 s, 11-20 s, and 21-30 s by -16, -29 and -35%, respectively. Females showed a difference (p < .001) in BLD of force between loads (-19% at 3%, -10% at 4% and +7% at 5%). Males had an increase (p < .001) in BLD of force from the beginning to the end of the WAnT starting with -18% (1-10 s), -38% (11-20 s) and -40% (21-30 s). WAnT had the highest BLD, followed by MVIC and grip strength.

Discussion: BLD in force is present during WAnTs and the sex-load interaction is important for determining this BLD during this maximal cycling test. Thus, when developing training or rehabilitation programs related to BLD in force, sex, load and exercise type should be taken into consideration.

Keywords: bilateral deficit; cycling; fatigue; upper body; velocity.

Figure 1

Experimental set-up and protocol. (A) Represents the upper body bilateral WAnT set-up. Wingates and MVICs were recorded in this position bilaterally. The graph shows the smart fit power force recording system, the modified Velotron upper body cycle-ergometer set-up and the software to perform the WAnT. (B) Unilateral WAnTs and MVICs were performed for each arm and the handgrip strength were performed in the same position holding a hand dynamometer bilaterally and/or unilaterally. (C) Experimental protocol.

Figure 2

Sex-load differences of the BLD during an upper body WAnT. The Y axis represents the BLD/BLF as a %. Males are represented in blue and females in red. (A) The left, middle and right graphs represent the 3,4 and 5% WAnT loads, respectively. (B) The left, middle and right graphs represent the average BLD during the 1-10s, 11-20s and 21-30s time points, respectively. The grey shadowed area indicates the area of bilateral deficit (BLD < 0). Significant differences between sexes are indicated with a solid line. Significant differences between loads and time points are indicated with the dashed line. *(p < .05).

Figure 3

Bilateral deficit during an upper body WAnT vs MVIC in males and females. (A) 3% load (B) 4% load (C) 5% load. BLD during the WAnTs are represented by the blue and red boxes for males and females, respectively and the BLD during MVIC with the dotted line and represented by the light grey and dark grey boxes for males and females, respectively. The grey shadowed area indicates the area of bilateral deficit (BLD < 0). Significant differences between tasks are indicated with a solid line. Significant differences between sexes are indicated with the dashed line. *(p < .05).