Which type of cardio is best for fat loss?
How many times have you wondered this? I think about it a lot but I recently took a course that broke it down very simply for me and now I want to share that info with you!
So if you’re looking to increase your endurance, improve your heart health or get a little leaner, this info is gonna help you!
First, let’s define cardiovascular activity.. it’s anything you do with your body that increases your heart rate and respiration that requires more oxygen and increases blood flow.
Now let’s break cardiovascular activity down into four segments…
Zone I- low and slow. This builds an aerobic base and aids in recovery.
Zone II- moderate. Moderate intensity cardio increases aerobic and anaerobic endurance
Zone III- intense. This builds high end work capacity.
Zone IV- VERY intense. This type of cardio builds intensity and strength.
Now let’s discuss what each of these four segments may look like..
Zone I- This would be something like going for a walk or taking a lovely little bike ride.
Zone II- This may include going for a run or going to a Zumba class. You could talk but it might be a little challenging.
Zone III- This may include doing some intervals of burpees and deadlifts or rowing. Perhaps something you would see in CrossFit or one of my workouts.
Zone IV- This is something you can’t sustain like a set of five heavy power cleans or an all out hill sprint. It should be noted zone IV can be anaerobic and may not require oxygen to get this done.
But you have to understand that this is incredibly subjective because if you’re just starting out that two mile jog may not be Zone II, and if you’re incredibly well conditioned someone’s zone II jog may be recovery for you.
To make this more definitive, we need to add some measurements to the four segments..
Zone I- is between 50-65% of your heart rate max. Your max heart rate is roughly 220- your age in years. This zone of cardio and should feel like about a 5-6 out of 10 rate of perceived exertion (RPE.)
Zone II- is between 55-75% of your HR max and should feel like about a 6-7 RPE.
Zone III- is between 65-80% of your HR max. This should feel like about a 7-9 RPE.
Zone IV- is 80-100% of your HR max and should feel like a 9-10 RPE.
How long you can sustain each of these is incredibly different for every human. It’s dependent on how you’ve slept and fueled and what you’ve trained your body to do.
Finally, what are the general fitness and fat loss benefits of each of these?
Zone I- Ever notice how amazing you feel after a walk outside or a yoga class? This is zone one. It promotes blood flow which means it can flush the lactic acid from sore muscles and help loosen things up. Focusing on nasal breathing can help calm your nervous system and make you feel chill and happy. It boosts serotonin. It also burn more fat than any other zone of cardio, however, because it doesn’t require a lot of energy, it doesn’t burn a lot of anything. This means it’s very muscle sparing too.
Zone II- Now, zone II may still be a bit on the recovery side for very well conditioned athletes. Like CrossFit athletes saying they’re going to swim laps or go for a jog for active rest. Remember.. this is all very subjective.. Zone II can promote recovery for some. But for all it helps us increase our endurance because this is something we’d be doing for 20+ minutes. Remember the very first time you went to an hour long spin or group fitness class and how tired you got? However, as you adapt you build endurance, and that’s what zone II aims to do.
You also burn fat here, albeit less than zone I, and more energy overall. So it can be muscle sparing which means fueling well is key if you want to maintain that hard earned muscle.
Zone III- This further improves our cardiovascular endurance so plan on being here for about 20 minutes or longer. It also builds your cardiovascular capacity so it’s great to do intervals of this so you can get faster. A real life example of this would be someone who wants to decrease their 5k time from 35 minutes to 30 minutes so she runs hard for 30 seconds followed by a 2 minute jog. That fast pace exposes her to zone III which isn’t yet sustainable but can be as she gains exposure and becomes conditioned.
This burns more energy than Zones I or II, but less fat than Zone I. It can burn muscle, so fueling properly is crucial if you want to maintain muscle mass.
Zone IV- This is truly very intense and includes anaerobic activity. Anaerobic means it does not require oxygen. In exercise this may include something like a 10 second all out sprint on a fan/ resistance bike or a really heavy set of five power cleans. You’re gasping when it’s over because that work you just did was without oxygen and now you need it, badly!! Zone IV may also involve something really intense like a 200m sprint or a minute of max effort burpees.
This is great for building strength, getting faster and improving your performance for sport. You burn the most energy doing this, which requires a longer recovery (between sets and I don’t advise doing this stuff on back to back days) and lots of fuel and sleep. It’s very muscle sparing.. in fact it might even help you build muscle. But because of how little time you spend doing it, it’s not the only thing you should do if you want to burn fat.
In my experience, doing a bit of all four is the best way to get the benefits of all four zones and best way to build and maintain a lean physique.
I include all four of these in my online personal training workouts for my clients!
If you don’t want to worry about making sure your plan includes all of them, work with me! Sign up for online personal training at kyrawilliamsfitness.com/signup
Your Coach,
Kyra