I’ve been struggling over which exactly I want to go for when trying to lose weight. Do I strive for a more accelerated aerobic heart rate when exercising, or try to stay in the fat burning range, which is the range below aerobic? I want to lose fat weight, but it seems like aerobic exercise, which is more intense and therefore raises the heart rate to the, um, aerobic range, would burn more calories. I don’t get it…
The heart rate thing is confusing. Here’s the short version: When you’re doing an activity, a certain percentage of the calories needed to support it come from stored fat, and a certain percentage come from elsewhere. The percentage of calories from fat is higher for a lower intensity activity than it is for a higher intensity one. But that doesn’t mean that the lower intensity activity burns more calories.
Suppose you expend 100 calories doing activity A for an hour, and 20% of them come from fat. That’s 20 total calories of fat. In that same hour, you could expend 300 calories doing activity B, with 10% of them from fat. That’s 30 total calories of fat. Clearly, activity B is better for fat loss than activity A.
There are a couple other good reasons to go for more intense exercise. Metabolizing stored fat requires that it be removed from storage, and that requires oxygen. Increasing your aerobic fitness allows you to take in more oxygen and therefore get more fat for fuel. The damage done by intense exercise will also raise your metabolism afterwards as your body recovers.
I use a heart rate monitor and swear by it. During my workouts last week I used 4,000 calories at ~40% fat consumption.
As you probably know when you exercise, you burn fat and carbs for energy. The intensity of the exercise can vary depending on your conditioning, experience and pain tolerance.
The thing is even though you’re laying waste to more calories per minute at higher intensity, you’re actually burning less fat. This is because of a ::making quote signs for something that’s never been properly explained to me:: “metabolic process” that someone a lot more degreed (paging Dr Karl) will more than likely come along and explain.
So with the help of a medical professional you will be able to determine your max heart rate and from that, if you stay in your 65-75% zone, you’ll burn fat. If you’re interested, my fat zone is 127-141 bpm, which I can sustain at 5 MPH for 50 minutes. Above that zone I’m strengthening my heart and pulmonary systems; I’m still burning fat, but at a lesser rate.
Ignore that “fat burning” shit. The calorie/hour rate is so low it’s only worthwhile if you have tons of time and patience. As such, it’s for people who are too lazy to go into the aerobic range and who have a lot of time on their hands.
This isn’t necessarily true. A lower percentage of the energy you’re burning comes from fat in high-intensity activity, but as I illustrated above, it can amount to a higher total of fat burned.
A good training program will work both low and high intensities. Both are good for you. Like so much else about our bodies, it’s not an either/or proposition. Just like strength training, you have to constantly change what you’re doing. If you do just high weight and low repetitions for strength training you get big muscles that are strong, but at the sacrifice of having low endurance and less dynamic strength. That’s why the pros and amateurs who know what they’re doing train in cycles. Usually, different forms of exercise are synergistic.
Different levels of intensity and forms of exercise provide different benefits in different ways. Improving your cardiac fitness boosts your basal metabolic rate (burn fat while you sleep or watch TV!) and makes it easier for you to muster maximal effort when you’re doing strength training. Training your body to efficiently utilize fat stores for exercise also changes your metabolism, improves your endurance in long-duration activities, and gives your body a chance to recuperate from higher intensity, more stressful exercise.
Do fat-burning days (low intensity) to recover from your aerobic training (high intensity) during the week. Do interval training sometimes to vary your heart rate during the workout itself. Cycle between concentrating mostly — but not exclusively — on fat-burning and aerobic fitness on a 6 or 12 week cycle.
Reported.