Self administered treadmill stress test. Stupid idea doing it unsupervised given my recent heart related concerns, but did it anyway. Resting heart rate prior to test 33. Reached intolerable exhaustion after 1.4 miles and heart rate max of 138. Based on the test result, my estimated VO2 max is 56, which is in the 55-60 range provided by other estimates.
Cooled down with an easy run of 2.6 miles afterward.