How Important is Cardio for Weight Loss?

Most people automatically think cardio for weight loss. But just how effective is it? What are the benefits and more importantly, can you really lose weight doing it?

Before we dive into this topic, let’s define what cardio actually is. According to the Mayo Clinic, “In a nutshell, the term aerobic means “with oxygen.” Aerobic exercise and activities are also called cardio, short for “cardiovascular.” During aerobic activity, you repeatedly move large muscles in your arms, legs and hips. Your heart rate increases, and you breathe faster and more deeply. This maximizes the amount of oxygen in your blood and ultimately helps you use oxygen more efficiently.” 

I will venture to say that more women automatically think cardio than men. I’m basing that on the fact that no matter what gym I’m ever belonged to, I’ll see the ‘regulars’ on the treadmill. The same women day in and day out. Those same women never, ever venture over to do any type of weight training. Here’s the interesting part…their physiques never change.

So, does cardio for weight loss actually work?

I will start the answer by saying that it depends. First of all, I don’t actually know what those women at the gym eat on a daily basis. If they have crappy diets, then at best, cardio is maybe only helping to maintain their current weight and not gain any more.

If your diet consists of a healthy balance of veggies, proteins, whole grains, and healthy fats, then yes, cardio should help you to lose weight…if you’re doing it right. Cardio, by definition in terms of exercise, requires you to raise your heart rate to a specific range. Your fat-burning heart rate is about 70% of your maximum heart rate. To determine your maximum heart rate, subtract your age from 220.

For example, if you’re 40… 220 – 40 = 180. So, your maximum heart rate would be 180 beats per minute.

Therefore, your heart rate for fat burning would be 70% of 180, or 126 beats per minute. No, it doesn’t have to be right on the dot. Most medical or health organizations agree on a range. For example, healthline.com suggests 126-129 beats per minute. They actually have a nifty little chart for ages 18-75.

The goal is to stay in that range for 20-30 minutes to get the most fat-burning potential for your efforts.

In the case of cardio, more is not necessarily better. I see some women on the treadmill when I enter the gym and more than an hour later, when I leave, they’re still at it.

Too much cardio can sabotage your weight loss goals!

Remember that cardio exercise is primarily for cardiovascular health. Fat loss is a bonus. But most fitness gurus will agree that too much cardio will actually start eating up muscle instead of fat. Two to three 20-30 minute cardio sessions per week is ideal. Here’s why this is important…

Muscle burns fat more efficiently than anything else. If you do too much cardio, you start burning away muscle and making your hormones do all sorts of things that don’t benefit fat loss. Why would you want to burn away something that helps you lose fat? That’s crazy talk, right? Think of marathon runners. Super thin, almost anorexic in appearance, long, stringy-looking muscles. I know you want to lose weight, but I’m almost positive that’s not the look you’re going for.

Ideally, a nice balance of cardio and resistance training will help you reach your weight loss goals faster than either one alone. For example, if you work out Monday-Friday, a nice balance would be Monday, Wednesday, Friday for resistance training and Tuesday, Thursday for cardio. It’s not impossible doing one or the other.

But if you could speed up the process, why wouldn’t you?