Can the craniocervical position modulate trunk muscle activation during a deadlift? A preliminary electromyographical analysis comparing conventional and sumo variations

Abstract

To prevent back pain and injuries, it is essential to select appropriate strength training exercises and to ensure their correct technical execution. The deadlift exercise and its variations seem to be highly effective at activating the posterior body kinetic chain. This exercise is therefore recommended, when is properly performed, for injury and back pain prevention in both athletes and inactive people. Therefore, a more comprehensive understanding of the deadlift exercise is still necessary. The aim of this study was to compare trunk muscle activity in conventional and sumo deadlift variations performed in various craniocervical positions. Similar submaximal loads were used across all experimental conditions. Three participants with strength training experience (age: 21.67±1.15 years, height: 169±10 cm, body mass: 75.13 ± 7.00 kg and body fat percentage: 9.87±2.49 %) performed the conventional and sumo deadlift variations in different craniocervical positions: neutral, extension and flexion. Participants followed a familiarization session applying the same submaximal load, number of repetitions, lifting velocity and exercise variations than in the posterior testing session. Trunk muscle activation was quantified via surface electromyography (EMG). Participants presented greater latissimus dorsi activation in the neutral condition, and this activation level was higher during the conventional deadlift variation. The greatest EMG response was found in the erector spinae muscles in the extension position, especially in the conventional variation. Finally, the greatest trapezium musculature activation was found in the flexion condition. During the sumo performance, the highest trapezium activity was detected in the middle trapezium fibers whereas during the conventional performance, the highest value was recorded in the superior trapezium fibers. Deadlift variations and craniocervical positions thus did trigger different levels of myoelectric activation in the analyzed musculature, showing how the craniocervical position influences the activity of posterior trunk musculature.