Applying an active lumbopelvic control strategy during lumbar extension exercises: Effect on muscle recruitment patterns of the lumbopelvic region

OBJECTIVE: Examine whether implementing an active lumbopelvic control strategy during high load prone lumbar extension exercises affects posterior extensor chain recruitment and lumbopelvic kinematics. METHODS: Thirteen healthy adults acquired an optimal active lumbopelvic control strategy during guided/home-based training sessions. During the experimental session electromyography was used to evaluate the activity of the posterior extensor chain muscles during high load trunk/bilateral leg extension exercises with/without application of the strategy. Video-analysis was used to evaluate thoracic/lumbar/hip angles. RESULTS: Implementing the active lumbopelvic control strategy decreased the lordotic angle during trunk (p=0.045; -3.2°) and leg extension exercises (p=0.019; -10°). The hip angle was solely affected during trunk extension (p<0.001;+9.2°). The posterior extensor chain (i.e. mean of the relative activity of all muscles (%MVIC) was recruited to a higher extent (p=0.026;+9%) during trunk extension exercises performed with active lumbopelvic control. Applying the strategy during leg extension exercises lead to less activity of longissimus thoracic (p=0.015; -10.2%) and latissimus dorsi (p=0.010; -4.4%), and increased gluteus maximus activity (p≤0.001;+16.8%). CONCLUSIONS: When healthy people are taught/instructed to apply an active lumbopelvic control strategy, this will decrease the degree of lumbar (hyper)lordosis and this influences the recruitment patterns of trunk and hip extensors. Hence, the possible impact on predetermined training goals should be taken into account by trainers.

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