If you ask a body builder or an advocate of the primal lifestyle they will probably tell you that “chronic cardio” is a very bad thing. The body builders will tell you that steady state cardio will result in very little fat loss and quite a lot of muscle loss. The primal advocates will tell you that endurance cardio is just plain bad for your heart, not to mention your hips, spine and every other joint in your body. Mark Sisson maintains that we are simply not designed to run for extended periods of time, however, over at runnersworld.com the debate rages as to whether 100miles of training a week is enough, or too much.
So where does the truth lie? What is the cause of this disparity in opinion?
It is a truth universally acknowledged that a single man, oops I mean, people like doing what they are good at.
For decades scientists have been asking test subjects to exercise this way or that and reporting the result of the average person, usually in terms of VO2max, a measure of a persons ability to utilise oxygen and an important determinant of their endurance capacity. However, until this century, the papers completely skimmed over the fact that, in every one of these tests, there are some people who will respond to an extraordinary degree and others, about 10% depending on the definition of non-response, that barely respond at all, or may even become less fit. Some people respond to interval training, and some to endurance training. Some respond to neither and some to both. It’s not just for aerobic fitness that this disparity is observed, some people can gain muscle mass easily, while others are “hard gainers”, and some can build strength, and others can build neither.
Those known as “hard gainers” in the body building sphere, are termed “non-responders” in the scientific papers. Non-responders often become non-exercisers, and that’s bad.
However, recently scientists have been asking if not responding to one type of fitness regime means you wont respond to any. A study was published last year, where 21 men and women were trained for 3 weeks with either endurance or interval protocols. Then they were asked to sit on the couch for 3 month (detrain) and they swapped protocols for another 3 weeks of training. The authors tested the participants on three fitness indicators, including VO2peak . About 25% of the subjects didn’t improve their VO2peak with either regime, about 25% improved with both regimes, but signifcantly, about half the subjects improved with one type of exercise and not the other. In fact the greatest change in VO2peak was seen in a subject with a negative response to the interval training.
But that still leaves 25% who didn’t respond to either type of exercise. We think of cardio as being the best way to improve our cardio fitness, that’s why we call it “cardio”, but it turns out, you can also improve your VO2max with resistance training, such as lifting weights. Another bunch of scientists studied people who were trained with either endurance or resistance regimes, and then swapped over after 2 months of detraining. In this study, everyone, responded to either the resistance training, or the endurance training (and most people responded to both).
So it seems that there is a fitness regime for everyone, you just have to figure out what that is. None of this takes into account actual performance in a real race, the motivation of the individual to succeed at a sport, or the pleasure someone gets from their chosen fitness endeavours, but what’s the bet that the editorial office of Runners World is full of people who respond well to endurance training, and the over at BodyBuilding.com the office is full of people who gain muscle easily?
For myself, I have now come to terms with the fact that I will never run 5k, but I enjoy interval training and lifting weights and can see (in a completely non-scientific way) the results of these activities.
What about you? Do you have a favourite type of exercise? Do you think you respond to it, or is there some other motivation that keeps you interested?