Cardio = A Shorter Life in the Long Run?

Although we will all die one day, and a degenerative disease will likely be responsible for putting many of us in a grave, there’s no reason why we shouldn’t be doing everything we can to avoid situations that increase our chances. This includes controlling free radicals and avoiding free radical damage, which has been tied to various chronic diseases (cancer, heart disease, Alzheimer’s, Parkinson’s) and early aging.


As I’ve outlined, the duration and intensity of exercise determines the amount of free radicals produced, and there’s a break-even point where this production overburdens our natural antioxidant defenses.


Meaning damage occurs when we go too hard, too long, and too often.

Training type is also a consideration, as exercise that requires oxygen (aerobic) to create energy, generates free radicals within mitochondria; which results in higher production levels and an increased susceptibility to DNA damage – the same mitochondrial specific DNA damage tied to early aging.

One analysis of skeletal muscle from a 90-year-old man revealed that only 5% of his mitochondrial DNA was full length, while that of a five-year-old boy was almost completely intact.

Lastly, is exercise variety.  The same repetitive movements result in consistent free radical and lactate production in the same muscle groups.  Arguably, this is why we see an increased risk of upper-respiratory tract infections and asthma and an elevated risk of heart disease in long-distance endurance athletes.


When you combine the free-radical factory, lactate build-up, negative hormonal consequences (high cortisol and low testosterone), and the muscle loss and damage experienced as a result, one has to question why anyone would consider running a marathon?


And more importantly, whether those training for and taking part in ‘many’ marathons in an effort to live a longer life are in fact living a shorter one?

On Monday, the popular fitness website printed an article I wrote speculating that question:

Stay Lean!
Coach Mike


Burn Less Calories and Live Longer?

Chronic Cardio = Excess Free Radicals

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