Muscle strength, muscle power, and muscle endurance are important factors for exercise performance. While many scientific studies show that warm-ups improve muscle strength and power during exercise, some recent studies report that warm-ups, including stretching, temporarily reduce muscle strength, explosive strength, and/or sports performance (American College of Sports Medicine, 2018; Garber et al., 2011; McHugh and Cosgrave, 2010). In this context, an investigation into the temporary effects of flexibility exercises on exercise performance is required. In the present study, the subjects were grouped into NWU, AWU, and ASW, and subsequently, muscular functions were assessed. The results of the present study indicate that NWU showed higher rates for both the flexor and extensor at 60°/sec, which is an angular speed for rating muscle strength, although the difference was not statistically significant. At 180°/sec, which is an angular speed for rating muscle power, AWU and ASW exhibited higher rates for the flexor and extensor, respectively, although the difference was not statistically significant. The total work at 240°/sec, which reflects muscle endurance, was higher in ASW for both the flexor and extensor, though not statistically significantly. Accordingly, whether or not stretching was included in warm-ups performed by nonathletes before participating in recreational sports activities, no significant differences were found in regards to exercise performance. Warm-ups appear to provide psychological and physiological preparation for exercise performance. Although warm-ups did not have a statistically significant effect on the variables of physiological aspect, they seem to have a meaningful effect on athletic performance by affording psychological stability, preparation, and confidence for exercise performance.