Students suffer from a decrease in physical activity during their education period. This lower level of activity could affect, through various paths, their academic performance, mental health, and satisfaction with life. In these two studies, we assumed that vigor, a positive affect variable, would act as a mediating variable in the above relationship, and thus, we proposed an instrument for evaluating vigor in academic contexts. In Study 1, 707 undergraduates (59.7% women) responded to the vigor scale adapted for students to test factorial validation (through confirmatory factor analysis) and obtain reliability indicators. In Study 2, 309 undergraduates (55.3% women) completed a questionnaire measuring physical activity, mental health, satisfaction with life, vigor, and academic performance to test a structural model of the relationships between the variables to obtain construct validity. A measurement model with three related factors, each representing one dimension of vigor, optimally fit the data, and the reliability indices were adequate (Study 1). Moreover, the mediational model confirmed a complete influence of physical activity on satisfaction with life, academic performance, and mental health levels through students’ vigor levels with optimal adjusting values (Study 2). Proposing an instrument such as the Shirom-Melamed Vigor Measure for students allows the opening of a research venue that is focused on the study of positive affects in academic contexts, as well as the testing of the physical activity pathways of action in obtaining positive results.

Background Students suffer from a decrease in physical activity during their education period. This lower level of activity could affect, through various paths, their academic performance, mental health and satisfaction with life. In this study, we assume that vigor, a positive affect variable, would act as a mediating variable in the above relationship, and thus, we propose an instrument for evaluating vigor in academic contexts. To attain this aim, the factorial validity and reliability of the proposed vigor scale for students is tested (Study 1), along with its construct validity (Study 2). Methods In Study 1, 707 undergraduates (59.7% women) responded to the vigor scale adapted for students to test factorial validation (through confirmatory factor analysis) and obtain reliability indicators. In Study 2, 309 undergraduates (55.3% women) completed a questionnaire measuring physical activity, mental health, satisfaction with life, vigor and academic performance to test a structural model of the relationships between the variables to obtain construct validity. Results A measurement model with three related factors, each representing one dimension of vigor, optimally fit the data (S-Bχ2 = 231.54; df = 50; CFI = 0.95; NNFI = 0.93; SRMR = 0.07; RMSEA = 0.07 [0.06–0.08]), and the reliability indices were adequate (Study 1). In Study 2, the mediational model confirmed a complete influence of physical activity on satisfaction with life, academic performance and mental health levels through the levels of vigor of the students, with optimal adjusting values (S-Bχ2 = 108.82; df = 62; p < 0.001; CFI = 0.92; NNFI = 0.90; SRMR = 0.05; RMSEA = 0.05 [0.03–0.06]). Conclusions Proposing an instrument such as the Shirom-Melamed Vigor Measure for students allows the opening of a research venue that is focused on the study of positive affects in academic contexts, as well as the testing of the physical activity pathways of action in obtaining positive results.