# Normative Muscle Activation Patterns During One and Five Countermovement Jumps

## TL;DR

This study examines muscle activation patterns during single and repeated countermovement jumps, focusing on specific leg muscles and their activity during take-off and landing.

## Contribution

The study provides normative muscle activation data for the vastus lateralis, vastus medialis, and biceps femoris during countermovement jumps and repeated jumps.

## Key findings

- Muscle activation in the vastus lateralis and vastus medialis is higher during take-off than landing phases.
- Biceps femoris shows similar activation in both take-off and landing phases.
- Performing five consecutive countermovement jumps does not induce greater fatigue than a single jump.

## Abstract

Studying normative values for muscle activation in the vastus lateralis (VL), vastus medialis (VM), and biceps femoris (BF), as well as the hamstrings/quadriceps (H:Q) ratio during the Countermovement Jump (CMJ). Determine whether there were differences between the CMJ and the trial of 5 consecutive CMJs (5 CMJ) and between the take-off and landing phases. A cross-sectional descriptive study. Thirty-one participants (20 females and 11 males, 22.52 ± 3.295 years, BMI 24.32, weight 58.23 ± 4.32 Surface electromyography has been used to determine muscle activation during the CMJ and 5 CMJ. Muscle activation in the VL, VM, and BF, as well as the hamstrings/quadriceps ratio in take-off and landing phases of the CMJ and 5 CMJ. The results show normative values in the VL, VM, and BF during both the CMJ and 5 CMJ, with the exception of the BF during the landing phase of the 5 CMJ. In conclusion, the activation in the take-off phase of the VM and VL is greater than during the landing phase. The BF shows similar activation in both the take-off and landing phases. The 5 CMJ does not induce greater muscular fatigue than the CMJ.