## 1 Introduction  
Throughout their careers, elite and amateur sports athletes are exposed to many musculoskeletal injuries that result in severe consequences for health, sports participation, training, or performance [1]. No less important, all rehabilitation plans involve an over-repetition of certain body movements in the same environment, representing a long, non-dynamic, and exhaustive process [2]. Consequently, injured players usually become unmotivated, affecting their mental health [3]. This harmful psychological condition can slow down physical recovery [4].  
On the other hand, the main objective of the various agents involved in a player's career is the rapid recovery from these injuries. One therapeutic resource that has been growing in interest in the last few years to improve the rehabilitation process's quality is virtual reality technology (VR) [5]. VR is a visual-based computer simulation that can reproduce a realistic and controlled environment [6]. Perceiving and interacting within the created environment are fundamental concepts of VR with important applications in building safe, customized, and enjoyable rehabilitation training environments [7]. Indeed, from a rehabilitation perspective, VR has become popular in therapeutic programs for different pathologic conditions [8]. Nowadays, it is possible to find several VR applications developed to support physical, physiological, and even social rehabilitation [5; 9]. However, in sports rehabilitation, in elite or amateur soccer players, limited data are available about the improvement and engagement of injured players using therapy methods during recovery.  
Recent studies developed in the sport context have reported that VR training improves balance, physical functional performance, and physical health compared to therapeutic exercise and may be considered a supplementary therapy to therapeutic exercise [10; 11; 12]. Several multidisciplinary research groups, including sports scientists, engineers, psychologists, and other health professionals, have hypothesized that sports players could benefit from VR environments during musculoskeletal injury recovery because those systems face participants with multimodal stimulation close to the real context [11]. Moreover, sports players are provided with suggestions (i.e., a set of external, temporal, or spatial stimuli) that aim to facilitate the performance of the exercise to be rehabilitated [2].  
Based on this rationale, VR gaming could be effective, convenient, enjoyable, entertaining, and affordable since participants receive immediate rewards when specific goals are completed. These VR environments may be an alternative for maintaining exercise adherence by increasing incentives and self-efficacy with positive visual and auditory feedback [12].  
However, it is still an open question which type, intensity, and duration of VR gaming in rehabilitation after a musculoskeletal injury can help players recover faster from injury, enhance cognitive awareness and motivation, and improve their decision-making capacity. For instance, more research is needed to better describe the implementation process of VR games and identify their advantages when included in a rehabilitation program.  
To address these fundamental requirements, this study describes the implementation of an entire rehabilitation session using a VR system to help elite or amateur soccer players recover from musculoskeletal injuries. Specifically, the main purposes of this study were (1) to describe a new technological solution for the rehabilitation of musculoskeletal injuries based on VR gaming, and (2) to analyze the variation in rated perceived exertion and heart rate of the participants when undergoing a rehabilitation session based on different VR games according to the standard components of the exercise training.