‘Fitness’ exercise (ie ‘cardio’) is the lowest stress, lowest risk exercise suitable for a sedentary person on the brink of a heart attack and death. ‘Fitness’ and ‘cardio’ activities (such as walking, yoga and Pilates) are NOT chosen or designed for their magical conditioning and rejuvenating effects on the body; they are chosen because the people for whom they are intended are so physically decrepit that superior forms of exercise (such as intense weight training) could literally kill them!
So, what is an hour of ‘cardio’ training a healthy athlete to be? To be the worlds worst endurance athlete? To be slow, weak and tired? Why would you train for these outcomes? Have you ever heard of any athlete wishing they were slower and weaker? From a body composition perspective, do you really think you will look more physically impressive because you are so much less physically impressive? If not, then why would you train for it?
Athletes can train for strength, endurance, stamina, agility, speed or 1001 other qualities. Whatever training they do for those qualities is sport specific athlete development. It is never “cardio”! “Cardio” is not for athletes. “Cardio” is a medical exercise intervention for sedentary people with cardio vascular disease! That is why it is called ‘cardio’.
The fact that the heart and circulatory system are involved in all physical activities does not make sport/conditioning specific training “cardio”. Actually, the fact that all athlete development practices provide a cardio-vascular benefit strengthens the argument as to why no athlete should ever do ‘cardio’: there is no purpose to additional training for an inferior capability an athlete already has. Whatever training an athlete does is already inherently superior to activities for people who are incapable of athlete training activities.
OK. So you understand ‘cardio’ is the lowliest form of exercise to hopefully prevent a terminally ill person from dying. You understand that ‘walking’ and ‘yoga’ and ‘aerobics’ are championed as great ‘cardio’, NOT because they are inherently excellent training modalities, but because people about to die cannot risk any more strenuous activity. Obviously, sufficiently unstrenuous activity is unlikely to negatively affect athlete-development practices if added to a training program. But if it does not subtract from your athletic endeavours then it was, by definition, an absolute waste of time. If it failed to make you the worse athlete that ‘cardio’ is training to be, then it was a failed intervention. That is good, if you do not want to be worse. But if the best effect you can hope for is no effect, then the better solution is: do not do it!
But what about all that theoretical stuff about fat burning and lipolysis and metabolic boosting and all those other technical biochemical processes you cannot measure and cannot affect? Well, most importantly, all of the supposed ‘benefits’ of cardio are in the context of sedentary people, comparing ‘cardio’ with doing literally nothing at all! It is not relevant to intense training athletes or body builders.
A more important general concept to understand in regards to all such arguments is: when you cannot measure or see the thing you are trying to affect then you are acting in total ignorance. When it comes to your body’s complex biochemistry, you have absolutley no idea how your body works or what its doing! Nobody does. Nor do you need to know. Everything you need to know you can measure. You can measure your food. You can measure your strength. You can measure every sort of sporting performance or physical performance attribute. You can measure your body composition. Why would you ignore everything relevant that you do know and can measure, to chase after a bunch of irrelevant, hypothetical nonsense that you cannot measure or see? Why would you choose to be ignorant?
Even more importantly, why would you ever engage in any activity medically prescribed to a terminally ill person, in the hope of benefits only relevant to a disease you do not have? For example, chemotherapy is a medical intervention for cancer that promises to cause even faster and greater indiscriminate WEIGHT loss than ‘cardio’. You don’t have cancer, but you do not have cardio vascular disease either. So why not just do chemotherapy for weight loss? Its equally insane, irrelevant and inappropriate to your goals as “cardio”.
A lower bodyfat percentage means a higher lean-mass percentage. In other words, being leaner means you are proportionately more muscular. That is math; not my opinion. So to create a leaner more muscular physique then you n are going to need to train to be a strength athlete. That, ideally, means weights. Ideally and logically it means heavy weights. It means lifting weights like a person who really wants to be strong. You do not want to be an aerobic, endurance athlete. How far you can run (or swim, walk or ride) has absolutely no relationship to how much muscle you have, nor, therefore, the percentage of you that is muscle or, therefore, your percentage of bodyfat. So don’t do it.
Diet and train to become the strength athlete you want to be. Everything you do to contradict that outcome will ensure you fail to achieve it. Don’t starve and eat zero carbs because that won’t make you a good strength athlete. And don’t spend hours per week training to be a slow, weak, bad endurance athlete because you will probably succeed!