In the ZONE!

We have all seen the little heart rate chart on the side of the treadmill telling us where our “fat burn zones” and “cardio zones” are… but what do they mean? Why can’t you just get on the treadmill, run a few miles and be done? Do these numbers translate to other pieces of cardio equipment? These are all things that need to be understood in order to effectively do cardiovascular exercise. If you are currently doing cardio without seeing the results you want then you could be overdoing it just as likely as underdoing it. Knowing how to manipulate your heart rate can give a more scientific approach to fat loss and help you hit your goals faster and more effectively.

 

The body has five heart rate zones in which it functions in. The first three zones (roughly 40%-85% of your max heart rate) are aerobic, meaning “with oxygen”. The last two zones (over 85% of your max heart rate) are anaerobic, meaning “without oxygen”. The primary fuel used by the body during aerobic training is fat, while the primary fuel used during anaerobic activity is carbohydrates. It is important to understand that both fuel sources are burned simultaneously in most zones, but knowing the primary source will help us determine where we want our heart rate based on our goal. This helps clarify what the heart rate charts mean by “fat burn zones”. Staying in the lower heart rates will allow you to exercise in the zones in which your body utilizes primarily fat for fuel. This could be anything from a fast paced walk, jog, or light run depending on your conditioning. The benefits from staying in these zones are not only to burn fat but to actually build your zone’s capacity. Your heart will get bigger as you train and become more efficient, allowing for higher heart rates to be reached and more calories to be burned in each zone. Pushing up into zone 4 and 5 will kick in the carbohydrate burn. This is why you see many endurance athletes carb loading or popping carb chews during long runs. While functioning in zone 5, sprinting for example, is only possible for a very short amount of time; but you can train your body to stay in zone 4 for a much longer period. In this zone you will not burn any fat but will burn significantly more calories than your lower zones due to the higher work load. During zone 4 work you should be very short of breath and find it difficult to talk (aka running or a spin class).

So, what does all this mean and how do we figure out these zones? The basic idea is that zones 1, 2, and 3 are the zones in which you burn fat but fewer calories, zones 4 and 5 you burn more calories but only carbs no fat. In your lower three zones you be able to work on weight loss and building an aerobic base, making the body more efficient at utilizing oxygen (resulting in more calories and fat burned per minute). In your higher two zones you will be able to work on cardiovascular endurance and performance, and also shed weight as long as you don’t overdo it on the calorie burn. Now, how do we find this info? The only truly accurate way to find your heart rate zones is to do a metabolic test that monitors your heart rate and oxygen levels during a short treadmill session. Many of you have done this with me at Life Time, known as a Cardiopoint. This type of test gives us accurate information specific to you not an average or formula based off of age. If you have access to this I suggest it over any other option, and if no Life Time Fitness clubs are near you, your doctor can tell you where to have it administered. A far less accurate option is using the max heart rate formula then using percentages of this number to determine your zone, which is what the chart on the treadmill does. The main problem with this is the fact that it’s not specific to the individual. It only takes into account your age so imagine three people are thirty years old, one is Lance Armstrong, one is you, and the other is 100lbs. over weight. According to this formula, all three would have the same zones and need to do the same intensity cardio to see results. If we followed this method in our scenario Lance would fall asleep, you would probably get a decent workout, and the overweight person would need to have a hospital close by. Point being just because three people are the same age doesn’t mean they all need to exercise at the same heart rate. Using this method can be used as a general guideline you just need to understand how to adjust for your level of conditioning. The max heart rate formula is simply 220-age, giving us the highest heart rate you should ever get to (keeping in mind that it’s easy to go higher if you are in better shape.) Once we have this number we can break it down to find our zones.  Here is a chart of how it will look and what each zone does.

% of Max Heart Rate	Type of Metabolism	Training in This Zone is Good For
Zone 1: 50 - 60%	Aerobic Fat	Getting Fit, Warming Up, Burning Fat
Zone 2: 60 - 70%	Aerobic (mainly Fat, some Carbohydrate)	Burning Fat Losing Weight
Zone 3: 70 - 80%	Aerobic (mainly Carbohydrate, some Fat)	Building Aerobic Endurance
Zone 4: 80 - 90%	Aerobic / Anaerobic Threshold	Raising Lactic Threshold
Zone 5: 90 - 100%	Anaerobic Carbohydrate	Increasing Maximum Aerobic Capacity

Now that we know all cardio is not the same and that being at different heart rates has different effects on the body, we should be able to better our cardio programs to hit our goals! Use this in correlation with last week’s blog to know what heart rate to be at for each goal. While doing HIIT you will definitely want to hit around 90% during your working portion, low intensity will be 50-70%, and during high intensity you will stay between 70-85%. BUT….remember that these percentages may need to be adjusted as you get better, that’s why it’s so important to have the metabolic test ran and take the guess work out. Also if you are exercising outdoors you will need a heart rate monitor to assure you stay in these zones. Polar and Garmin make some of the best ones; they come in all sorts of shapes and colors.

POLAR

 

GARMIN

If you would like to order one or discuss which one is a good fit for your needs please feel free to contact me for more info. It’s time to get serious and stop all the meaningless wondering around on the treadmill or elliptical! Your time is too valuable to waste doing cardio incorrectly so know your ZONES and your goals and get there! Get off your damn cell phones and iPads and focus on hard work, it’s time to BRING IT!!!