Background: This study aims to determine the effects of kinesio tape (KT) application on acute-onset muscle soreness and the extensibility of the calf muscles in endurance athletes. Methods: A one-arm repeated-measures randomized cross-over controlled study design investigated 55 endurance athletes, including 10 cyclists, 30 badminton players, and 15 long-distance runners (mean age 16.40 ± 2.69) from different stadia in Delhi NCR, India. KT and sham tapes (ST) were applied randomly to right and left legs (prone position) in a cross-over manner with a gap of 72 h. Ankle dorsiflexion range of motion (ADFROM) and pain due to acute-onset muscle soreness were assessed immediately and 10 min and 30 min after treadmill running, using a universal goniometer and numeric pain rating scale (NPRS), respectively, along with the time to fatigue. Results: A statistically significant difference was observed for the NPRS when the mean scores obtained for the KT and ST groups were compared immediately after cessation of running; however, the difference was not statistically significant in the NPRS score that was recorded ten or thirty minutes after. The range of motion increased significantly after the application of both the KT and the ST. After running on a treadmill, the range of motion decreased significantly with both the KT and ST, and the decrease was similar. Conclusion: KT was more effective in reducing the pain intensity immediately after running and increased the time spent running on the treadmill before fatigue set in among endurance athletes. In addition, the two taping methods (KT or ST) were equally effective in enhancing calf muscle extensibility (for both right and left legs) immediately after application. However, both taping methods failed in limiting the decrease in ankle ADFROM after treadmill running.