Variation in physical fitness and the impact of COVID-19 in young Colombian adults: An 11-year observational retrospective study

Introduction. Low levels of physical activity (PA) have become one of society's major problems. Physical fitness is a predictor of health. Objective. The present study investigates temporary changes in lower limb power, running speed, flexibility and cardiorespiratory fitness before and after COVID-19. Material & Method. Cross-sectional data were collected from 2.942 young people (17-21 years old) of both sexes between 2011 and 2022. Performance was analyzed in relation to the explosive strength of the lower limbs based on standing long jump (SLJ), flexibility (sit-and-reach), cardiorespiratory resistance (20 m Shuttle Run Test) and speed (SP-30 m). Results.The results indicate significant (p<0.001) p <0.001) strong and moderate (ES = 0.45 to 1.45) decreases in the shuttle run in most periods for young people of both sexes, although the decline in women's performance was twice that of men. The SLJ also showed a significant (p<0.001) p <0.001) weak and moderate (ES = 0.07-1.86) decrease in most periods, with a stronger decline in men. The sit-and-reach test did not demonstrate significant differences by either sex or period. In the SP-30 m, significant (p<0.001) p <0.001) weak (ES = 0.12) decreases were observed in the race time for men only between 2011-2022, while there were significant (p<0.001) p <0.001) strong (ES = 1.8-2.0) increases for women in some periods. Conclusions. The silent pandemic of physical inactivity and sedentary behaviors has had a greater effect than COVID-19 on levels of physical inactivity and sedentary behavior. The results of this study indicate a gradual and sustained reduction in the physical fitness of young adults throughout the past decade, which was greater than that caused by confinement due to the COVID-19 pandemic. This indicates that the level of physical fitness is so low that confinement did not generate significant effects on the reduction in physical fitness in the young adult population. In other words, the silent pandemic of physical inactivity and sedentary behaviors has had a greater effect than COVID-19 on levels of physical inactivity and sedentary behaviors.