By Sebastian Rebollo

Master in physical Activity

Certified Strength and Conditioning Specialist

In this article I will try to explain the intensity training zones for aerobic endurance training. Now that we know how to check our heart rate, it’s time to put that method in to practice and control our training. This article is not to tell you which training zone you need to be in for your own personal objective, but instead to give you the big picture of the training zones. You will have a better understanding of all of them and use them properly in your personal training.

The training intensity zones that we are explain here are endorsed by USA Cycling.


The maximum heart rate in this zone is between 50 – 64%. At this intensity we can speak with someone without any difficulty. It’s an important zone because here is where we can recovery after an intense training or when we’ve done interval training in combination with other intensity zones.


Here the maximum heart rate is between 65 – 74%. This zone is where we are going to create our aerobic endurance base, so it’s a fundamental zone in the training process. Generally this phase is located at the beginning of our training sequence. Similar to the recovery zone, you will be able to  maintain a normal conversation.


This zone E2 is where we are going to increase our muscle glycogen stores. Note that spending too much time working in this particular zone is not quite beneficial to improve fitness. The maximum heart rate here is between 75 – 84%. This is a hard zone because it’s between E1 and VO2 max, its more beneficial if we use this zone in our interval training where we can be in the zone and out the zone, getting the benefits of this zone, but without the extreme fatigue.


This is one of the most important zones that we need to incorporate in our training schedule. If we monitor our heart rate well and stay in this zone, we are going to see real improvements in our physical performance. Interval training is the most appropriate type of training for this particular zone, because the intensity level is very high, and we cannot maintain that intensity for very long. We are going to train here to increase our tolerance to lactate (training at lactate threshold). If you are an endurance type of athlete this is one of your main goals of improvement. The maximum heart rate here is between 85 – 91%.


This is the most difficult zone to train in and preferable for very hard training athletes. This is training at the maximum level of intensity and without the foundations from the other training zones, you can’t obtain the true benefits. The benefits of this zone are to improve our maximal consumption of oxygen and increase our cardio output. The intensities are between 92 – 100% of or maximum heart rate.

I hope this article was useful for anyone who can read it, in future articles we are going to put more examples of training in each zone and how we can incorporate it into our weekly routine.

Disclaimer: No training program can or will protect you from injury. All athletic sports carry with them an element of danger. In the case of a fall, collision or other accident, you may be injured or killed, regardless of the type of athletic training you may have participated in. A training program itself could even result in an injury in certain situations. The only way to certainly avoid being injured while training or participating in a sporting activity, is to not participate in any sports or training activity.