# Effects of Physical Exercise on Substance Use Disorder: A Comprehensive Review
## 3 Results  
### Assessment and Impact of Physical Exercise on the Quality of Life of Individuals with SUD  
Quality of Life (QOL) is a multidimensional construct based on the interaction of physical, emotional, functional, and social components, which generate a sense of well-being and life satisfaction [26]. One of the most commonly used tools to assess QOL in this  
Figure 1: Flow diagram of the different phases of the review process. population is the Short Form-36 Health Survey (SF-36), which evaluates these components across eight dimensions. Among these, mental health-related aspects, specifically depression, anxiety, and stress, are the most studied in this population. Depression is defined as a psychiatric disorder characterized by persistent sadness, loss of interest, and various emotional, cognitive, and physical symptoms [27; 28]. Stress, on the other hand, is defined as the inability to cope with external demands, while anxiety refers to a state of agitation in anticipation of a threat [29]. Additionally, sleep quality has recently been included as a variable in studies, demonstrating its relationship with QOL and mental well-being in both healthy populations [30; 31] and in individuals with SUD [32]. The SF-36 also has a shortened version [33] consisting of 12 questions (SF-12), which assesses two dimensions out of the eight included in the full version. However, this shorter version has been infrequently used with the target population in the reviewed literature, likely because it provides less information than the full questionnaire. Another tool used to assess QOL in individuals with SUD is the \"Quality of Life Scale for Drug Addicts (QOL-DA)\", which consists of 40 items measuring four dimensions: physiological, psychological, social, and symptomatic. The QOL-DA is a valid, reliable, and sensitive tool for measuring QOL in opioid-dependent individuals, although recent studies have also applied it to populations with methamphetamine and amphetamine addiction. In addition to these tools for assessing health-related quality of life, the \"Test for the Evaluation of the Quality of Life in Addicts to Psychoactive Substances\" (TEQLAPS) is available in Spanish. It consists of 22 items--18 positive and 4 negative--with five response options for each item: nothing, little, sometimes, quite a lot, and a lot [34]. Among all the tools mentioned, the SF-36 is the most widely used tool to analyze QOL in various populations, including individuals with SUD [26; 35; 36; 37; 38]. Several studies have demonstrated that QOL in individuals affected by SUD is significantly lower than that of healthy individuals, as measured using the SF-36 [39; 40; 41]. Similarly, QOL has been negatively correlated with the likelihood of relapse into drug use (r = \(-\)0.59, \(p\) < 0.01) [32]. Therefore, improving QOL is a key variable in the rehabilitation process for patients affected by SUD. In recent years there has been an exponential increase in the number of studies using physical exercise to improve QOL in this population [17; 35; 42; 43; 44]. This prior literature reveals a high heterogeneity in interventions, which include different types of exercise (mind-body, continuous cardiorespiratory, interval cardiorespiratory, strength training), intensities (low, moderate, and high, as presented in Table 1), frequencies (1 to 5 sessions per week), and durations (8 weeks to 12 months). The literature establishes the effectiveness of physical exercise in improving QOL in this population, showing beneficial effects on anxiety, depression, irritability, stress, and withdrawal symptoms. However, no specific type of exercise or intensity has been identified as having a significant effect on all these variables [11; 45]. The following section will analyze the impact of physical exercise on each of these dimensions, considering the underlying mechanisms and the current scientific evidence available in the literature.