A BIOMECHANICAL MODEL OF THE CERVICAL SPINE DURING CYCLING

With the objective of estimating the internal forces in the cervical spine during cycling, nine subjects pedaled in three postures. The image of the sagittal posture of the spine was recorded through filming and the muscle activity of the cervical extensors was registered. Reflexive markers were placed on anatomical points on the head and the cervical spine. One subject was submitted to radiological exam of the head and cervical spine in the sagittal plane with lead markers placed on the same anatomical points of reference. Muscular force was calculated using the inverse dynamics technique. The results demonstrate that muscular strength and the RMS value increase significantly (

LOWER LIMB FORCE, POWER AND PERFORMANCE IN SKATEBOARDING

The aim of this study was to quantify the contribution of muscle force and power of the lower limbs to the performance of the Ollie in beginner level skateboarders. Ten male athletes who had practiced for at least two years were submitted to three kinds of test: (1) maximal voluntary contraction of the knee and hip extensor muscles; (2) vertical jump tests, Counter Movement Jump (CMJ) and Squat Jump (SJ); and (3) a test developed specifically for this study, to measure the maximum height achieved during the Ollie manoeuvre. The data obtained were submitted to simple linear regression analysis. The results demonstrate that the variance of the Ollie manoeuvre (

LACTATE THRESHOLD USING MATHEMATICAL DETECTION OF THE EMG DURING INCREMENTAL PEDALING EXERCISE

The purpose of this study was to determine the validity of using the EMG as a noninvasive method to estimate LT in non-athletes subjects. Twenty-four non-athletes subjects performed an incremental exercise protocol that consisted of stepwise increases in power output of 25W every 3 minutes until exhaustion at 80 rpm. The EMG was recorded from the right vastus lateralis and right rectus femoris each 15 seconds. Blood samples were taken every 3 minutes. The LT was determined using a log-log transformation model. The EMGT was determined mathemathically using MATLAB® software that models RMS response to gradual exercise using linear regression. The results showed high the correlation coefficients between EMGT and LT, and the validity of using EMG to estimate the LT power output was confirmed