Effect of Two Modalities of Training with Physical Exercises on Balance, Muscular Torque and on Biomechanical and Metabolic Variables During Gait of Elderly People

Abstract

Human gait is the most executed movement during daily activities and its promotes important functional indenpendence for the subject. During walking the correct action of all body segments is essential to maintain the stability and prevent falls. However, during aging, changes in the sensory-motor and muscleskeletal system could reduces the ability to execute complex motor tasks, as walking and increase the risk of falls in older adults. In line of this, the aim of this study will analyze the effect of two different training modalities of physical exercise on biomechanical and metabolic variables during gait of older adults. Forty-five volunteers of feminine gender divided into two groups will participate of this study: young group (YG), composed by 15 volunteers with age between 18-25 years old; and older adults group (OAG), composed by 30 women aged 60-80 years old, physically fit and non-institutionalized. Ramdomly, the OAG will subdivided into two groups: the groups that will be trained with Pilates Method exercise (PG; n=15); and control group (CG; n=15), which will perform a training with conventional exercises. Before the begining of data collect will be applied the Berg Balance Scale and the Mini-Exam of Mental State, which the scores will be used as exclusion criterium and to classify the sample. The procedures for the data collect will be divided into two different visits for the data collect environmental. In the first day, the volunteers will perform the muscle torque assessment, as well as, will be determined the preferred walking speeds on overground and on the treadmill. During the second visit to the data collect environment the volunteers will familiarize with walking on treadmill, then will perform the economy walking test, gait test and balance test. In the week after the evaluation will begin the training of PG and CG, then after 8 weeks of training these assessments will be performed again. The volunteers of YG will be only performing the initial assessment. The assessment of muscular torque will be performed on a isokinetic dynamometer during the movements of flexion, extension, abduction and adduction. The gait test will be performed on the treadmill and will be composed by: normal gait task; fear of fall gait test; cognitive dual task gait; motor dual task gait; and motor and cognitive dual task gait, which will be performed randomly. Walking economy test will be performed on a treadmill during 8 minutes. The balance test will be composed by two different perturbations proximal and distal from center of mass. During all assessments will be collected electromyographic signals (EMG) from the muscles: multifidus, rectus femoris, gluteus maximus, biceps femoris , as well as, during walking economy test and gait test will be collect kinematic data. For the data analysis will be developed routines in Matlab (Mathworks®), where will be calculate: for EMG signal analysis, the muscular activation, antagonist cocontraction and muscular activation variability; for kinematic data, cadence, double stance time, single stance time, balance phase time, stride length and antero-posterior, medio-lateral and rotation of trunk displacement; for the torque analysis will be calculated the peak of torque and rate of torque development; and for the walking economy test, the oxygen expenditure.