The Ultimate Endurance Guide for Zone 2 Workouts (2025)

If you’re looking for the ultimate endurance guide for Zone 2 workouts, you’ve come to the right place. Zone 2 training has become very popular for those looking to increase their fitness, cardiovascular health, and performance in the gym. In this article we will review the fundamentals of Zone based training. I will also explain the proper method of performing Zone 2 workouts, ensuring that you improve your health and performance as quickly as possible. Keep reading for more.

Readers of this website will know that I’ve spent many years writing fitness programs for all types of athletes. I have programs for bodybuilders, weight lifters, crossfitters, and much more. However, my most popular programs are for hybrid athletes who want to build muscle and strength, as well at their cardiovascular conditioning.

If you’ve ever seen my hybrid or endurance programs, you’ll know that I include a lot of Zone 2 workouts. This is because research shows that it’s one of the most effective methods of increasing your aerobic capacity. The benefits of Zone based training are manifold.

Not only does it improve performance, but it can help with weight loss, and increase work capacity for strength training. Strength athletes, with a larger aerobic capacity, can return to their resting heart rate much quicker, enhancing recovery time. Here’s a quick overview of Zone 2 training below.

---

Zone 2 Workouts Overview

• Moderate power output
• Can be done with nearly any full body exercise type
• Long duration, best done for 45min or more, 3 days per week
• Primarily burns fats for fuel
• Use nasal breathing / talk test to verify power output
• Ideal for building endurance through aerobic exercise

---

Now that we have a good idea of the broad topics we will discuss in this guide for Zone 2 workouts, let’s cover some definitions for Zone based training. In the next section we’ll define some commonly used terms. Moreover, we will review the basics so you have a better understanding exactly what Zone 2 training is, and what it does. Let’s get to the overview.

Zone Based Training Overview

Endurance athletes have been using Zone based training for a long time. There are several systems that incorporate different training zones. In some training systems you’ll see seven zones, where as most researchers use three distinct training zones.

For the purposes of this article we will use the most popular five zone training system. This is what companies like Garmin use when tracking your fitness metrics. It’s also the Zone based training system athletic trainers and coaches are referring to when they mention Zone 2 workouts.

There are several ways to determine which training Zone you’re in. Cyclists will often use power output directly from a power meter. Where as runners and other athletes have historically used heart rate zones as a percentage of max heart rate.

While these are common ways of determining which training Zone you’re in, they are not the most accurate method. To truly determine which training zone you’re in, you must use a blood lactate monitor. What’s lactate you might ask? You’ll find out in the next section.

If you like this kind of article make sure you sign up for our email list below. We’ll send you all the latest articles as soon as they’re released.

---

Tier Three Tactical Email List

---

Blood Lactate and Zone Based Training

If you’ve read any endurance based research you’ll know that researchers often measure lactate, or lactic acid. Even though lactate is chemically an acid, it isn’t responsible for the burning you feel in your muscle fibers. That is a myth that just won’t die.

Lactate is produced during anaerobic energy production. In simple terms, it is a method for your body to produce adenosine triphosphate or ATP, very quickly. If you need a lot of energy for high power output movement, then lactate will be produced.

The only drawback to lactate production is that it isn’t sustainable. The by-products of anaerobic energy production can build up quickly, ultimately requiring you to stop or slow down, due to changes in pH within your skeletal muscle cells. This is why you can’t sprint for minutes on end.

Before we go any further we need to define the different training Zones, so we can understand why Zone 2 workouts are so beneficial for fitness, and cardiovascular health. If you’d like you can find the full video version of this article here.

Five Zone Training System Definitions

In our Five Zone training system we primarily differentiate between Zones by power output, or percent of heart rate max. Even though we’ll mainly be talking about aerobic and anaerobic training, it’s important to understand that all energy systems operate simultaneously in your body, during any movement.

You shouldn’t ask if a certain exercise is aerobic or anaerobic. That is the wrong way to think about it. It’s better to ask how anaerobic or aerobic an exercise is. If we take a look at the chart below we can see the differences in heart rate training zones, as shown by the lactate curve.

The 5 Training Zones

We can see that Zone 1 activities are low-intensity exercise, fueled by fat. This is normal every day movement. Things like a brisk walk, brushing your teeth, or arguing with strangers in the comments section, are all done in Zone 1.

Zone 2 is the highest power output aerobic threshold zone. It relies on fat for fuel, and no appreciable level of lactate is produced. This is lower exercise intensity, and it can be sustained for many hours. We’ll discuss how to make sure you’re actually in Zone 2 later on.

Zone 3 is the beginning of meaningful lactate production. You can see on the graph that it ramps up slowly, within this training zone. In Zone 3, your body uses a mix of sugar and fats as a fuel source for ATP production. It can be sustained for a few hours, depending on fitness level. This training Zone is also called sweet spot training by some coaches.

Zone 4 is very anaerobic, and produces a large amount of lactate. The top end of this training zone is also called your lactate threshold. This is where your body can still deal with the by-products of lactate energy production. Zone 4 is somewhat sustainable. A well trained athlete can maintain this level of output for an hour or so.

Zone 5 is where the accumulation of lactate is so great your body can no longer remove the by-products. It’s very high power output, and very unsustainable. It relies primarily on sugar as an energy source. Elite athletes can maintain this for 20 minutes or less.

Sprinting and Aerobic Capacity

It’s important to note that even at this highest power output zone, your body might still produce 50% of its energy via your aerobic energy system. The chart below highlights that even short sprint events use a lot of aerobic energy.

This highlights the importance of improving your aerobic energy system, and the best way to do this is with Zone 2 training. We’ll discuss this in the next section. If you want to try my most popular hybrid program, to build your strength and aerobic capacity, then check it out below.

Aerobic Training with Zone 2 Workouts

Zone 2 workouts improve your body’s ability to make ATP in a more sustainable way. Most athletes don’t actually understand that high-intensity interval training or HIIT is actually more effective in increasing your bodies ability to produce ATP via your mitochondria.

This has the obvious draw back of being time limited. Anyone who’s done high-intensity exercise can tell you that you wan’t to stop almost immediately. This type of training has the added drawback of being difficult to recover from, due to muscular soreness, and glycogen depletion.

Zone 2 Research

This leaves us with easier training, like Zone 2. In this research paper, the authors stated that they were able to see a noticeable improvement in mitochondria size, and density, in as little as 6 exercise sessions. Moreover, they also reviewed another research paper that covered Zone 2 training volume.

They found that there was a negligible increase in mitochondrial volume and density, for groups exercising more than 3 days per week. Groups that did 4,5, or even 6 Zone 2 sessions per week showed no greater mitochondrial benefits, than the 3 day group.

While this is good news for us, we need to be cautious as this is only one study. I can say that I’ve found that most athletes do well with 3 Zone 2 sessions per week, during base building portions of the training cycle. In the next section we’ll review which type of training protocols work the best.

Which Training Protocols Work Best?

This is truly the million dollar question. For the purposes of this article we will discuss which training protocols produce the most increases in endurance capacity and power output. This meta-analysis examined the most effective training methods for endurance athletes. This was their conclusion.

Highly trained/elite middle- and long-distance runners are encouraged to accumulate >100 km·wk⁻¹ while following a pyramidal TID approach on a hard day–easy day basis. A polarized pattern might be also effective. Linear periodization is generally recommended for this population although further research is needed to understand whether other periodization models are effective in improving performance and physiological determinants. Runners should decrease the amount of training at vLT2 (z2), as well as increase the amount of training in z3 (race pace) during the competitive period.

Training Periodization, Methods, Intensity Distribution, and Volume in Highly Trained and Elite Distance Runners: A Systematic Review

If you don’t speak researchese, then I’ll translate their findings. They compared two types of training programs for distance runners, pyramidal and polarized. Pyramidal training has about 70% Zone 2 training, 20% Zone 3/4, and 10% Zone 5, depending on training cycle. Polarized has around 80% Zone 2 training, with 20% Zone 5.

They found some benefit to a pyramidal approach, with an increase in training intensity as the competition season nears. I think there are some great takeaways from this piece of research.

Research Key Points

First, for anyone who isn’t going to the Olympics for an endurance sport, it makes sense to spend a large portion of your cardiovascular training time in Zone 2. I think 70% is a reasonable goal, when aiming to build your aerobic energy system.

Research is also clear that mitochondrial efficiency is best improved with hard Zone 5 training. That should be a small portion of your training time. It’s hard to recover from, and it doesn’t seem to benefit from large training volumes.

Now that we have some concrete metrics, based on scientific research, let’s go over a sample training plan for our five zone training system.

Example Training Week: Zone 2 Heavy

To make the math easy, let’s say that you have 10 hours to devote to endurance exercise each week. For most athletes that would mean that you are working on your Zone 2 endurance for 7 hour per week. This is 7 hours of low intensity training. I don’t know about you, but I can tell you that most athletes aren’t doing that much easy work, even thought they really should be.

Approximately 2 hours of training should be done within Zones 3 and 4, in this scenario. This leaves us with 1 hour done at maximum intensity, with hard training intervals. Check out the sample week below.

The first thing I want to say is that this is a crazy training week. For 98% of you reading this, you should not go out and attempt this. Ten hours of running per week is an advanced training volume. This also represents the maximum amount of training you could do, based off of research.

The point of this example week is to show you just how much training volume you should be doing at Zone 2. This goes double for my hybrid athletes and crossfitters. Almost everyone is neglecting their Zone 2 training volume.

Zone 2 Workout Training Options

A more reasonable version of this would be half the volume, or 5 total training hours. This would leave you with an hour Zone 2 long run, and much shorter Zone 4/5 workouts. It’s also worth pointing out that you don’t have to run to do Zone 2, lower intensity workouts.

I tend to use my Assault Bike one Zwift. I’ve been doing this for the last year or so, and I really enjoy it. It cuts down on the boredom drastically. You could choose traditional cycling, swimming, rucking, rowing, or any other full body movement.

In the next section I will provide some training tips for Zone 2 workouts, such as how to make sure you in Zone 2. After that, I will provide some of my best hybrid programs that will increase your fitness level with Zone 2 workouts.

Zone 2 Training Tips

The most common problems I see with Zone 2 training are athletes that are training too hard. This is especially common for those that run. You have to be a very fit person to be able to jog within your Zone 2.

To give you an example my VO2 max is in the low 50’s and I absolutely cannot jog up any incline and stay in Zone 2. My pace on the flats is almost 11:00min per mile. That’s definitely easy run pacing! You should expect to alternate between jogging and walking if you’re a runner.

Finding Your Zone 2 Pace

A great way to determine your training zones is to pick up a fitness tracker watch from Garmin, like my favorite Epix 2 (Amazon Affiliate Link). These watches, and their software will provide very accurate data to keep you within zone during a training session. I’m a training nerd and don’t mind spending money on those products, but that doesn’t mean you have to.

The simplest method to determine if you’re in Zone 2 is via nasal breathing. Simply close your mouth and breath through your nose while exercising. If you can’t, you’re going too hard! This is similar to the talk test, where you have a conversation while working out.

If you find you can’t speak whole sentences, then you’re also going too hard. These tests are great because you don’t even need a heart rate monitor to do them.

For hybrid athletes, hyroxers, and crossfitters, I think working on something that gives you watts for a power output reading is ideal. Use an exercise bike, or assault bike. It will keep you within Zone 2. Now let’s review a few of my best programs incorporating Zone 2 training.

Don’t forget, you can still try my most popular hybrid training program, featuring a lot of Zone 2 training.

Zone 2 Workout Programs

In this section I’m going to cover some programs that will help you build strength, muscle mass, and Zone 2 fitness. These programs are appropriate for athletes that have safe form on the primary lifts, and have some experience in the weight room

---

Hybrid Programs with Zone 2 Workouts

• 8 Week Hybrid Hypertrophy Program (Size + Conditioning)
• 8 Week Hybrid Strength and Endurance Training Plan (Part 1)
• 8 Week Hybrid Strength and Endurance Training Plan (Part 2)
• 8 Week Hybrid Bodybuilding and Endurance Training Program (Part 1)
• 8 Week Hybrid Bodybuilding and Endurance Training Program (Part 2)
• 12 Week Apex Hybrid Performance Fitness Plan (Part 1)
• 12 Week Apex Hybrid Performance Fitness Plan (Part 2)

---

Now that we’ve covered my most popular hybrid programs, that use Zone 2 training sessions, let’s finish this article up with my final thoughts.

Final Thoughts

The biggest take away for you should be that Zone 2 training is important for almost all athletes. Even pure strength athletes and bodybuilders can benefit from Zone 2 training. After all, increased mitochondrial function will help them recover from hard sets, and workouts, much quicker than they would otherwise.

It’s also very beneficial for your overall health, especially heart health. Low VO2 max has long been known as a strong correlate to many serious medical problems, like diabetes, and heart disease.

Zone 2 Beginner Athletes

If you’re new to Zone 2 training you need to find training methods that you enjoy. You might find that hiking or rucking outside keeps things interesting. I almost always listen to Audible while I’m doing Zone 2 workouts, to help pass the time. I also tackle different challenges on Zwift to keep engaged.

Experiment with different methods of training, and don’t be afraid to change training methods from week to week. Most athletes need a general increase in aerobic capacity. You don’t have to stick with a certain type of Zone 2 cardio workout to accomplish this. If you plan on competing in those endeavors, then you should stick to your sport.

If you have any comments or questions put them below, and I’ll get you an answer. Now get out there and get training. Don’t forget to join the email list below.

---

We are not affiliated with any other company or entity including CrossFit Inc. Each workout plan is entirely owned by Tier Three Tactical and we recommend that you exercise under the supervision of a professional coach. It’s also recommended that you seek medical clearance from a licensed medical doctor before starting any fitness program.

Any links to Amazon.com or other merchants are affiliate links. This means we receive a percentage of any purchase you make from them, after using the link. It costs you nothing extra, and helps immensely. Thanks for your support.