“How hard do I have to exercise to achieve my goals?”
When most people think of metabolism they think of the number of calories their body burns. They think in terms of resting metabolic rate (RMR) which we discussed my last article, Resting Metabolic Rate: The Key to Weight Loss. There are actually two sides to the metabolic coin that you need to understand to maximize your results. The second side is Exercise Metabolic Rate (EMR). Like RMR, EMR is most accurately tested with a New Leaf Metabolic Assessment. EMR tells us the NUMBER and the TYPE of calories our bodies burn when we exercise. No, the numbers on your treadmill or elliptical are not very accurate. Why? Because they generalize. They do not take into account your body composition, genetics, exercise and diet history, hormones, and on and on. There are a few critical metabolic markers we want to know about a person to most accurately design their cardiovascular training program. They are:
– Aerobic Base
– Anaerobic Threshold
– VO2 Max.
Your Aerobic Base (AB) is the heart rate at which your body burns the most calories while still using fat for fuel. Because of the all-too-common belief that we have to work really hard to get fit, most of us exercise in a way that is not all that efficient at burning the fat stored in our body. With proper zone training, you can make the most of your time spent exercising. By building a solid fitness foundation (or base training), you will begin to increase your ability to exercise at a higher intensity with seemingly less effort. And that, absolutely, improves your Threshold. Your Anaerobic Threshold (AT) is the theoretic point where your body stops burning fat for fuel. AT is the point where your breathing becomes labored and your muscles burn. Working out at your AT has both risks and benefits. Spend all your time exercising above your AT and you may improve your fitness level but you will not be able to lose weight or body fat.
Work at this point for too long without having built a solid fitness foundation and you may injure yourself or cause “burnout.” While you build your fitness foundation, you’ll exercise up to the intensity of your AT. That way, you’ll teach your body to burn fat more efficiently. Over time you’ll see your AT heart rate increase, and you’ll also see an increase in the percentage of fat you burn while working at higher heart rates. Then you can burn more total calories and more fat calories and get twice the benefit !! In addition to your AB & AT, specific heart rate training zones should be established based on your fat utilization between those two points. This is extremely beneficial as it provides for extreme customization to your cardio program. When you know – and use – your AB, your AT, and your heart rate training zones, you get maximum benefit from your workout:
– more energy
– more fat burning
– better performance
– improved fitness
You want to use your AB & AT to determine your heart rate training zones because we know that as your fitness level improves, so does your ability to exercise. Your heart rate ranges for each training zone will change over time, but your ultimate goal is the same: burning more calories with less effort! Peak VO2 Without getting overly technical (you can do a Google search for more if you’d like) your Peak VO2 is the maximum amount of oxygen you used during the assessment. Peak VO2 essentially measures your heart and lung fitness and can be used to determine your exercise potential. For most beginners, this number is not of critical importance. As your fitness level improves so will your Peak VO2. The first priority of a cardiovascular training program is becoming a better fat burner. The focus is first on increasing Aerobic Base and then raising the Anaerobic Threshold. This combination will give you the ability to:
– burn more calories
– burn more fat
– do more work with less effort
So, what do you do if you do not have a place to get assessed within driving distance? Unfortunately, the only way to measure AB is with an assessment. AT, however, can be guesstimated fairly accurately. The first step is a mathematical formula. I know, these formulas are very general and do not take all the individual factors into play. We’re just going to use it to get in the ballpark. Subtract your age from 180. If you’re really de-conditioned subtract 10. If you’re really conditioned add 10.
The next step is to go through a graduated exercise test using Rate of Perceived Exertion (RPE). Choose your mode of cardio exercise (bike, treadmill, elliptical, etc.). Start off real light just to get warmed up for a few minutes. From there you want to gradually increase the level of intensity (resistance, speed, incline, level) every 2 minutes. You’re looking for 4 cues:
1. Increased rate of breathing that forces you to breathe through your mouth
2. You can only maintain very short sentences. Just a few words comfortably.
3. Burning sensation in the legs
4. Increased mental focus required to maintain consistent level of activity
When you have noticed all four of these you can be reliably sure that you’ve reached your Anaerobic Threshold. Check your heart rate. That’s your AT. Now, with just the AT we cannot get very specific about what your cardio program should be because we do not have an accurate fat burning profile. As a general rule, 80% of your time should be spent below AT and 20% of your time should be sent at or above AT in a given week. In my next article, we’ll take a defect dive into heart rate training and heart rate monitors. Stay tuned!
Featured Image: 2nd Round Fitness