I have often shared the statement first made by Kenneth Cooper, the “Father of Aerobics”: “If you are running for more than 30 minutes, you are doing it for more than your health.” It is a great Segway to a discussion of why to do cardio and how much is necessary.
Before considering what cardio to do and how much is necessary, the first question is to ask “why?” Everyone has their reason for doing (or not doing) cardiorespiratory exercise. These include: performance, weight (hopefully, fat) loss, and heart health.
Performance. There are a wide range of performance goals. One might be training for anything from 5-K races to marathons to any of the ever widening range of ultra-distance races, triathlons, or simply “general physical preparation” or GPP for sport. Whatever the goal, “opportunity costs”. In other words, the greater the demand for cardiorespiratory performance, the more specific the training must be. This also means the less opportunity to train for other “unrelated” training variables (e.g., strength training). Specificity rules. Remember: the body system makes specific adaptations to imposed demands. The bigger the goals, the more precise the training required—the more the athlete will require qualified coaching.
Fat loss. Most of us want to lose some body fat. Given that over two-thirds of Americans are overfat or obese, most of us need to lose body fat. For the most part, losing body fat is a matter of expending more calories than one consumes. Cardio allows one to increase the energy expenditure. Unfortunately, it isn’t just as simple as eating less and burning more—if the goal also includes building and sustaining muscle mass. Thus, when trying to improve the body physique by losing fat and adding muscle, cardio becomes a supplement to weight training.
The greater the emphasis on endurance and leanness, the less gains that can be expected in the strength and hypertrophy area. The extensive cardio will burn fat and improve performance, but the caloric expenditure will rob muscle of the calories and nutrients necessary for hypertrophy. For most endurance athletes, hypertrophy is undesirable (extra body weight requires more effort to move), so weight training is counter-productive—to a degree.
For the one who desires increased muscle hypertrophy and leanness, cardio has to take a backseat to weight training and careful dieting. Care must be taken to minimize the recovery demands that take away from muscle growth. In such cases, caloric expenditure might require low-intensity steady-state (LISS) cardio, which burns calories at a slower rate, but with less detriment to muscle mass. It also takes considerably more time (to burn the same calories) than other methods, such as moderate- or high-intensity steady-state exercise or HIIT. The greatest concern here is what works for the individual. Everyone responds differently.
Heart health. Many weightlifters—particularly powerlifters—choose to avoid cardio all together. For most, it is a matter of “opportunity costs”—i.e., time spent doing cardio takes away from time building strength and muscle mass. I can, and should, be stated that it would behoove the weightlifter to at list do the minimal cardio necessary to keep the heart healthy. Eventually, the desire to live will outweigh the desire to be big and lift heavy. It is always better to keep the heat healthy than to rehabilitate an injured heart.
Fortunately, the minimum effective volume for cardiorespiratory health is a rather low threshold—relatively speaking. The American Heart Association recommends at least 30 minutes of moderate-intensity aerobic activity at least five days a week for a total of 150 minutes. Less time is required if the activity is vigorous (25 minutes, 3 days a week). With higher intensity training—e.g., very HIIT—less time is requires. Even if one cannot exercise quite to the intensity of the Tabata IE1 protocol (and most can’t), short HIIT workouts 2-3 times a week, performed such as to not interfere with strength training recovery will greatly benefit the heart.
The key to a healthy heart is to be as active as possible and as often as possible. So, do what you can.
Be your Best today; be better tomorrow.
Carpe (cardio) momento!