Purpose: Various online physical education activities and methods have been applied to colleges in the Philippines during the COVID-19 confinement. However, much remains unknown about the effects of the physical activity given to students. This study aimed to analyze the validity of online synchronous physical education classes using a progressive cardio workout program among college students. Method: One hundred and ninety-four physical education students enrolled in morning class voluntarily participated. Baseline and posttest measures included resting heart rates, training heart rates, heart rate recovery (HRR), and the YMCA 3-min step test (YMCA 3MST). Results: The progressive cardio workout program over the 8 weeks significantly improved the training heart rate of the participants, X[superscript 2][subscript F](7) = 475.397, p = .001. Also, there is a significant difference between pretest HRR (Mdn = 24) from posttest HRR (Mdn = 16), W = 10,863, p < .001. The pretest HRR was significantly higher than the posttest HRR, the rank--biserial correlation, r[subscript B] = .586, suggests that this is a large effect size. Further, the pretest YMCA 3MST (Mdn = 120.5) was significantly different from the posttest YMCA 3MST (Mdn = 116), W = 10,946, p < .001, the rank--biserial correlation, r[subscript B] = .286, suggests that this is a small to medium effect size. Conclusion: This study demonstrated that the 8-week progressive cardio workout program significantly improves the participants' cardiorespiratory fitness based on the pre- and posttraining heart rate, HRR, and YMCA 3MST results.