Cardio Doesn’t Exist

The inimitable James Steele II has a new publication out in the Journal of Exercise Physiology, called “Resistance Training to Momentary Muscular Failure Improves Cardiovascular Fitness in Humans: A Review of Acute Physiological Responses and Chronic Physiological Adaptations”

Here’s the abstract:

Research demonstrates resistance training produces significant improvement in cardiovascular fitness (VO2 max, economy of movement). To date no review article has considered the underlying physiological mechanisms that might support such improvements. This article is a comprehensive, systematic narrative review of the literature surrounding the area of resistance training, cardiovascular fitness and the acute responses and chronic adaptations it produces. The primary concern with existing research is the lack of clarity and inappropriate quantification of resistance training intensity. Thus, an important consideration of this review is the effect of intensity. The acute metabolic and molecular responses to resistance training to momentary muscular failure do not differ from that of traditional endurance training. Myocardial function appears to be maintained, perhaps enhanced, in acute response to high intensity resistance training, and contraction intensity appears to mediate the acute vascular response to resistance training. The results of chronic physiological adaptations demonstrate that resistance training to momentary muscular failure produces a number of physiological adaptations, which may facilitate the observed improvements in cardiovascular fitness. The adaptations may include an increase in mitochondrial enzymes, mitochondrial proliferation, phenotypic conversion from type IIx towards type IIa muscle fibers, and vascular remodeling (including capillarization). Resistance training to momentary muscular failure causes sufficient acute stimuli to produce chronic physiological adaptations that enhance cardiovascular fitness. This review appears to be the first to present this conclusion and, therefore, it may help stimulate a changing paradigm addressing the misnomer of ‘cardiovascular’ exercise as being determined by modality.

Key Words: Aerobic, Metabolic, Molecular, Myocardial

Download the paper free here.

One thing strikes me when reading papers from guys like Steele, and Fisher, and McGuff, as opposed to other scientists in the exercise and nutrition fields: They live to a high standard of logical analysis. You won’t find any gross generalizations or assumptions here. Maintaining such a strong will toward truth is so difficult because relativism and mysticism are seductive—it’s easy and tempting to explain things away as mysterious, magic, or different for everyone (I find myself doing so on occasion, in fact).

Whenever you find people that can live up to a high standard of logic and truth, I highly recommend you learn as much as you can from them. Such people are hard to find.

A quick review of Steele’s review: the paper systematically discusses the acute and chronic adaptations resulting from physical training, and explains the most efficient way to achieve these advantageous adaptations (hint: resistance training to momentary muscular failure). As I see it, this is definitely the starting point for anyone wanting to gain a scientific understanding of proper strength training. I’m sending this paper to my exercise science professor, who I’ve been trying to introduce to HIT for almost 2 years now, and hopefully he sees the overwhelming scientific merit of this style of training. I guess it all depends on how strong his will toward truth is.

Conclusion: Congrats to James for such a kickass publication. Rock on.