Whether a New Year’s resolution or a long-term lifestyle change, many dieters spend hour after frustrating hour dancing all over their living room floors to the latest aerobics video, pumping away at the elliptical trainer, or wearing out their running shoes as they burn up the pavement just to see their waistlines expand even more. Though slow and steady cardio workouts can be beneficial in moderation and coupled with high-intensity exercises, by themselves, they can cause more harm than good. Just how much cardio is too much?
Compared to other forms of exercise, steady-state workout routines, such as what you get from walking, jogging, bicycling, or swimming, have been shown to burn the most calories. At a glance, it seems like a routine of only cardio would be best for weight loss. However, as the saying goes, things are not always what they seem. Many who take on such a lifestyle are disappointed after several months to find that pair of skinny jeans they’ve been saving for after their big weight loss still not quite fitting.
In a recent study by the European Journal of Applied Physiology, prolonged cardio can cause your body to suppress T3, which is a natural fat-burning hormone. Adding insult to injury, another stress hormone called cortisol begins to increase after about 20 minutes of cardio, which has been scientifically shown to store fat, especially in the abdominal area. Thus, although you burn calories during endurance training, your body is designed to cling tight to its fat. As a result, you simply spend the rest of the day feeling tired, sluggish, and much more hungry than you normally would have been. In fact, studies have shown that people who intensely train in cardio, on average, eat 100 calories more than what they burn off after exercising to compensate for the post-workout hunger.
What about Muscle?
Nearly everybody has heard the old argument that cardio makes you shed lean muscle mass, but why would that be? Scientific research has shown that during cardio the body slows down its production of the human growth hormone (HGH), which is essential for muscle maintenance. This hormone naturally decreases after the age of 18, which is why it becomes increasingly hard to build muscle the older you get. Muscle loss corresponds to slower metabolism, which also works against your weight loss goals.
Does this mean we should stop doing cardio entirely? Most experts say no. Because cardio is effective at burning calories and has proven health benefits for heart and respiratory function, moderate amounts coupled with strength or high intensity training may be just what the doctor ordered. These higher intensity workouts will build muscle, release T3, and increase HGH, which all work together to burn fat. When cardio exercises are shorter, they don’t have time to reverse these muscle-building/fat-burning benefits, adding an extra round of calorie burning and giving you the best of both worlds. So, instead of endurance running for 60 minutes, consider weight training followed by 20 minutes of running. If you prefer running the whole time, perhaps try varying your intensity by sprinting then slowing down and repeating the process. Do not focus your attention exclusively on aerobic or anaerobic exercise.
The key to successful weight loss is not the quantity of exercise you do, but the quality. If you are struggling, perhaps it’s time to mix up your routine a little. Also remember that the mechanisms behind losing weight are often complicated and any number of other factors such as diet or hormones could also be hindering you from your goal.
The most important thing to remember is to never give up. Many others have lost weight, and you can too. With the right diet and exercise, you will be fitting into those skinny jeans before you even know it.