## 1 Introduction  
In the modern world, unhealthy lifestyles, including physical inactivity and bad dietary habits, contribute to the development and spread of diseases associated with metabolic commitment, such as metabolic syndrome (MetS). MetS is defined as a clustering of metabolic abnormalities, such as central obesity (increased waist circumference), dyslipidemia, hyperglycemia, and hypertension, according to the guidelines of the International Diabetes Federation (IDF) [1; 2].  
[PERSON] et al. pointed out that overweight and obesity are emerging major health issues, which are closely related MetS [3]. Body mass excess can promote adipose tissue stored in the abdominal cavity and intramuscular adipose tissue (IMAT) [4; 5]. It is known that these conditions directly affect the biomechanics of movements [6; 7; 8], leading to decreased mobility, strength, and ability to perform common activities of daily living [6; 9; 10]. In obese individuals, lower extremity overuse injury is caused by multiple mechanisms, including increased load bearing with ambulation, altered gait biomechanics due to abnormal body mass distribution, a systemic pro inflammatory state [7; 11; 12; 13]. The affected joint kinetics may increase the risk of musculoskeletal injury, with the development of osteoarthritis, especially in the knees [7; 14], and the impairment of the range of motion (ROM) [7; 15]. Reduced ROM can imply the limitation of the knee flexion [15], which is required to perform activities of daily living [16]. ROM is a parameter of physical evaluation, since it can allow the identification of joint and muscle limitations. Moreover, it is used for the evaluation of individuals during the rehabilitation process [17].  
In obese individuals, the lower limb muscles (flexors and extensors) are frequently committed [9; 10]. In consequence, decrease of muscle strength and power, and premature fatigue [6] are observed, leading to impaired motor performance [18]. As these individuals are not motivated to practice regular exercise, methods to increase adherence including exercises that minimize the impact on the joints are necessary [19]. Among the different kinds of exercises, whole body vibration exercise (WBVE) may be an option for the management of obese individuals [20; 21].  
WBVE involves exposing individuals to mechanical vibrations that are produced in a vibrating platform (VP). These vibrations are transmitted to the body of the individual that is in contact with the base of the VP. Some parameters must be adjusted (frequency, peak-to-peak displacement, and peak acceleration) considering the clinical condition of the individual [22]. Similarly, if the person is sitting on an auxiliary conventional chair [23] or wheelchair [24] with the feet on the base of VP, the individual will also experience WBVE.  
Authors evaluated the effects of WBVE on MetS individuals, and important responses were observed, such as improvement of quality of life and flexibility [25; 26]. Moreover, WBVE is safe and effective to treat muscle complications in populations with different disorders [27; 28; 29; 30; 31] as well as healthy individuals [32; 33].  
Surface electromyography (sEMG) is an adequate tool to evaluate neuromuscular effects of WBVE [27; 34; 35; 36]. An increased sEMG activity after WBVE indicates that more motor units are recruited [34].  
It is well described that WBVE can improve joint mobility [29; 37; 38]. Moreover, [PERSON] et al. found that WBVE in combination with quadriceps resistance exercise compared with quadriceps resistance exercise alone showed significantly greater improvement in knee flexion and extension in individuals with knee osteoarthritis [39].  
The aim of this study was to analyze the effects of WBVE on neuromuscular activation through the electromyographic pattern of the vastus lateralis muscle and on range of motion of the knees in MetS individuals. The study hypothesis was that WBVE would increase neuromuscular activation and range of motion of the knees of MetS individuals.