Neuromuscular and biochemical responses of the hamstrings to a <i>Flywheel Russian belt Deadlift</i> in women and men

The purpose of the study was to analyze hamstrings muscle damage and recovery after a novel <i>Flywheel Russian belt Deadlift</i> (FRBD) exercise using neuromuscular tests and associated biochemical markers of structural damage. Maximal voluntary isometric contraction (MVIC) torque and rate of force development (RFD) over several time-intervals by the <i>90º</i>_<i>hip</i>:<i>20º</i>_<i>knee</i> <i>test</i> (standing isometric test for the hamstrings) and range of motion (ROM) <i>Jurdan test</i> (combination of <i>active knee extension test</i> and <i>modified Thomas test</i>), together with serum biomarkers of muscle damage and oxidative stress, were tested at baseline and +24h, +48h and +72h in healthy, untrained and physically active 15 females (age= 21.5±3.4 years) and 15 males (age= 21.4±1.9 years). FRBD-induced muscle damage was observed as a reduction in MVIC torque and RFD at all time-intervals until +72h. Also, hamstrings neuromuscular capacity reductions were associated with serum biomarkers of structural and oxidative damage. However, only males showed ROM changes. Overall, the FRBD triggered a decrease in hamstrings neuromuscular capacities, and an upregulation of biochemical markers of structural and oxidative damage until +72h. The <i>90º</i>_<i>hip</i>:<i>20º</i>_<i>knee</i> <i>test</i> provides an adequate reliability to screen hamstrings recovery in both women and men after flywheel training, through MVIC torque and both early and late RFD.