A Neuromechanical Investigation of the Dip in Males
Creators: name: McKenzie, Alec Kenneth
Publisher: name: Southern Cross University
Year: 2021
Subjects: The dip
Exercise technique
Surface electromyography
3D motion capture

description: Background: The dip is a popular exercise prescribed to recreational exercisers and athletes to increase upper body strength and endurance. There are many technique variations that can increase (i.e., the ring dip), or decrease (i.e., the bench dip) the overall movement complexity, and different prescription models (i.e., low or high number of repetitions, or the use of additional resistance), which may explain the dip’s popularity across a wide range of and training contexts. Despite its popularity and flexibility in prescription, the dip is yet to be systematically investigated, particularly regarding the potential differences in the kinematics and muscle activation patterns in different dip variations and conditions.
description: Research aim: The overall aim of this thesis was to profile and compare the kinematics and muscle activation patterns occurring during three common dip variations, i.e., the bench dip, bar dip and ring dip. Additionally, this thesis aimed to investigate the effect of fatigue on the most common dip variation, the bar dip.
description: Methods: To answer the thesis aims, two observational studies were conducted. Study 1 investigated the kinematics and muscle activation patterns of three common dip variations, i.e., the bench, bar, and ring dips. This involved 13 healthy male volunteers, experienced in bodyweight dips, who completed four repetitions of each dip variation in the institution’s biomechanics laboratory. Study 2 investigated the effects of fatigue on the bar dip’s kinematic and muscle activation patterns. Study 2 involved 15 male volunteers who completed one set of bar dips to volitional exhaustion.
description: During both investigations, the participant’s full-body kinematics were collected using 3D motion capture and surface electromyography was used on nine shoulder complex muscles to measure the muscle activations. For both kinematic and muscle activation data, all repetitions were normalised to 200 data points, each representing 0.5% of a complete dip repetition. The average of repetitions 2-4 were used for analysis in Study 1. To compare data between the three dip variations in Study 1, a one-way repeated-measures ANOVA was used. The average of repetitions 2-4 and the average of the final three successfully completed repetitions were used as the non-fatigued and fatigued conditions, respectively, in Study 2. To compare data between the two conditions, Study 2 used a paired-samples t-test.
description: Major Conclusions: Study 1 identified distinct differences in the three dip variations. The bench dip targeted the triceps brachii relatively sufficiently when considering overall movement complexity and activations of other agonist muscles. Yet peak muscle activation were significantly less than during both the bar and ring dips (average peak triceps brachii: bench = 0.83 ±0.34mV, bar = 1.04 ± 0.27mV, and rings = 1.05 ±0.40mV). However, the bench dip required the greatest amount of shoulder extension (peak shoulder extension: bench = 88.13 ±8.86o, bar = 78.20 ±9.84o, rings = 61.72 ±13.51o), which is a potentially vulnerable position to induce shoulder injury. We suggest the bench dip should not be frequently used in strength training or rehabilitation protocols. The bar dip used a more optimal body position compared to the bench dip and increased the activation intensities of most muscles tested. Therefore, we suggested that bar dip regressions, when the load at the bottom position can be moderated, may be effective for training the muscles of shoulder flexion and elbow extension. The ring dip required similar kinematics to the bar dip, except participants used less shoulder extension. The ring dip may be optimal when targeting the pectoralis major but has inherent risks of falls, particularly in novice and fatigued exercisers. Finally, fatigue did not cause significant changes to the bottom position of the movement but did cause an increase in peak muscle activation amplitudes of the gravity-opposing muscles (e.g., serratus anterior, lower trapezius, and latissimus dorsi). Therefore, some levels of fatigue may be safe and effective when prescribing the bar dip.