This is an awesome tl;dr on a study released by the author that shows something anyone who has performed a widowmaker already knows: Anaerobic resistance training builds cardiovascular fitness just as well as aerobic. And best of all, the author makes the full text of the study freely available.

The Life & Times of James Steele II: There’s No Such Thing As ‘Cardio’ – Resistance Training to Momentary Muscular Failure Improves Cardiovascular Fitness in Humans: A Review of Acute Physiological Responses and Chronic Physiological Adaptations