Background: Sustaining regular exercise is a major public health challenge. Self-directed, goal-oriented exercise programs may enhance autonomy and adherence compared to traditional supervised approaches. Objects: This study evaluated the effects of an 8-week individualized, goal-oriented exercise program on physical fitness and body composition in college students and assessed the durability of these effects following an 8-week washout period. Methods: In a non-randomized, fixed-sequence design, 24 healthy young adults (19 males, 5 females) completed an 8-week self-directed exercise intervention, followed by an 8-week washout and an 8-week control period. Physical fitness (vertical jump, standing long jump, handgrip strength, one-leg stance) and body composition (body mass index, skeletal muscle mass, body fat percentage) were assessed. Data were analyzed using repeated-measures ANOVA and effect size estimates. Results: Significant improvements were observed in all fitness measures post-intervention (p < 0.01). Large effect sizes were found for vertical jump (Cohen’s dav = 0.87) and standing long jump (dav = 0.99), while handgrip strength and one-leg stance showed moderate effects (dav ≈ 0.65). However, no consistent changes were detected in body composition variables. Fitness gains declined rapidly during the washout period, indicating transient adaptation. Conclusion: An 8-week goal-oriented, self-directed exercise program effectively improved physical fitness but not body composition in young adults. These findings support the utility of autonomy-supportive models, though the rapid reversal of gains highlights the critical need for sustained engagement strategies.

In this study, we compared the organoleptic and other qualities of fermented milk containing 10 or 15% purple carrot extract that had either been previously fermented with Aspergillus oryzae or not fermented. Fermentation characteristics, pH, chromaticity, viscosity, viable cell counts, and sensory evaluations were measured. The pH and acid values did not differ between purple carrot extract fermented with Aspergillus oryzae and non-fermented extract. Viable cell counts were significantly higher in 15% purple carrot extract fermented with Aspergillus oryzae compared to the control after fermentation. Regarding characteristic changes, purple carrot extract fermented with Aspergillus oryzae group showed a lower red value but higher yellow value compared with non-fermented purple carrot extract due to heat-sterilization. Both fermented and non-fermented extract groups showed significantly increased viscosity compared to control. In the sensory evaluation, 15% purple carrot extract fermented with Aspergillus oryzae showed the highest score. In conclusion, addition of 15% purple carrot extract fermented with Aspergillus oryzae resulted in a superior fermented milk product.