CrossFit aims to improve you overall as a human, to be fitter. But does it specifically improve cardio? Let’s find out.
CrossFit can improve cardiovascular fitness (or cardio), by sustained physical activity, utilising metabolic conditioning workouts of varying degrees, carried out at high intensity. The metric of cardiovascular fitness is measured by one’s ability to effectively deliver oxygen to the muscles and is also known as V02 Max. CrossFit is known for its Workout Of the Day – or WOD – that aims to improve the overall cardiovascular fitness of the person, along with 9 other domains of human fitness.

What Is Metabolic Conditioning in CrossFit?
Metabolic conditioning is generally comprised of 2 parts: aerobic and anaerobic. It utilises exercises that increase the available energy stores in the body. The aim of the conditioning (or training) is to optimise the delivery of oxygen around the body to the muscles, in order to be able to do more with less energy.
CrossFit classes will often have a strength or skill block, followed by metabolic conditioning (MetCon / Metcon), which is the Workout Of the Day (WOD), geared toward improving one’s efficiency at utilising stored energy.

Breakdown of the 2 types
Aerobic Conditioning is the optimising of the heart muscle, to ensure more effective in delivering oxygen to your muscles.
It is usually improved with endurance-based workouts. Usually, the exercise is light to moderate in intensity and carried out over a protracted period of time.
Anaerobic Conditioning is the type of training that breaks down the glucose stored in the body, without (ana) the use of oxygen.
The exercises are shorter than that in aerobics, but higher in intensity.
This Best Gym Hacks post here helps further break down what a CrossFit class looks like.
Healthy habit
A British healthcare information charity (Cochrane) declared that interval training increases cardiovascular fitness in a review of this topic, and is effective in helping hypertensive individuals, thus the reducing risk of cardiovascular disease.
What’s Your Lactate Threshold?
Lactate is a byproduct of glucose, created by your muscle cells during periods of intense use, normally during exercise.
So that means the more glucose you are using, the more lactate you’ll be producing.
When this builds up, it’s that feeling of heavy legs, for example. The exercise becomes harder and muscles less responsive.
High or low lactate and what it means
Lower blood lactate levels are seen in top athletes in any field. This comes down to their better than average capability to clear lactate quicker and more effectively, than say amateurs, juniors, or everyday hobbyists doing the same sport.
Stats and a study
Here is an interesting article from San Millán 2009, showing cyclists and their respective differences in blood lactate levels.
This Training Peaks article helps gives you visual representation and disparities between ability (and in some places age) levels.
In essence, what this Train Peaks article shows us is that the higher the ability, the lower the blood lactate levels.
So the ‘fitter’ you can get in the cardio sense has a direct correlation in a reduced level of lactate in your bloodstream.
What happens in CrossFit with lactate?
During CrossFit, the use of glucose increases as the skeletal muscles work hard to keep up with demand, and therefore an increase in lactate can be seen (known as a spike).
As we become better in a cardio sense, our body’s ability to keep a lid on lactate build-up gets better, thus improving our cardiovascular output – awesome eh!
Are CrossFit Workouts Good For Cardio?
Due to the broad variance of workouts that seek to improve a number of fitness domains, CrossFit overall is good for cardiovascular improvement, and it is one domain it aims to improve.
However, the overarching philosophy of CrossFit is to be fitter in 10 different domains of fitness, so to that end, there are other training methods out there which are more focussed on improving cardio alone, which may therefore have more significant results.
That said, a member recently in one of my affiliates wrote a piece for our affiliate blog and newsletter, where she proudly proclaimed the improvement in her V02 Max.
This was great for her, great for our coaching team, and great social proof of the benefits of cardiovascular improvement by doing CrossFit.


If you’re interested in how long it takes to improve when starting CrossFit, read this Best Gym Hacks article here. It’s packed full of data for the geeky amoung us.
What Are The 10 Best CrossFit Cardio Workouts?
As we’ve seen already, the aim to improve your cardio fitness is to increase V02 max and your lactate threshold. So there are specific WODs or exercises that are good for enabling you to go stronger for longer.
Let’s split this into the two types noted above and see what they might look like: anaerobic (short and intense) and aerobic (longer and lighter).
The permutations are literally infinite, but there are some standout favourites that are worth noting, many of which you might already know.
Here’s my top 5 picks of each, all of them Benchmark or Girl WODs. This will help you differentiate between the 2 types, but also so I can testify to their required stimulus having done them all (OK all but one) multiple times in various formats.
This Best Gym Hacks post here busts the myth that CrossFit is bad for you. Find out why it’s not.

Anaerobic CrossFit WODs
1. Fran
21-15-9 Thrusters 42.5/30kg and Pull Ups
Ever heard of Fran lung? It’s the fizziness felt in your capillaries after your 45th pull up.
This workout is fast and savage, and it’s been around a long time, in terms of CrossFit.
Other variants of this WOD are Frantasy Land and Fat Fran. Both longer and harder than Fran, with the same baseline of movements. (Frantasy Land is pushing into the aerobic domain).
WOD Hack: Unbroken all the way. Don’t stop. Breathe on the Thrusters, at the top.
2. Diane
21-15-9 Reps For Time
Deadlifts (100kg / 225 / 70kg 155 lb)
Handstand Push-Ups
Again, quick and dirty. Like Fran, this is expected to be as unbroken as possible and rapid. Weight is not overly heavy, allowing for speed and quick transitioning. World record times are just over 1 minute! Think Dan Bailey…
WOD Hack: Unless you’re an unbroken machine, 11/10, 10/5 and 9s on the Deadlifts are good. 7’s is also a good strategy for the Deadlifts. You want to do big or unbroken HSPU wherever possible. She’s over fast.
When your coach is throwing in intervals, Tabata, EMOMs and other ancillary stuff, just remember, it’s all good prep for the huge variety of work you’ll be doing in your upcoming classes.
3. Karen
150 Wall Balls for time
9kg / 6kg (20/14lbs) 10ft Men, 9ft Women
This is a simple workout. Extremely leggy and shouldery.

WOD Hack: The trick is to not ‘rest’ with your arms elevated, as you’re waiting to receive the ball. Leaving them elevated creates unwanted lactic build-up in the arms and shoulders, meaning fatigue will set in sooner, and you’ll break your sets more often.
I did a twisted version of this in CrossFit Cape Town where 3 of us had 450 Wall Balls between us, except when the ball dropped, one of us had to do 20 cals on the Ski Erg.
Honestly, it was one of the most hideous WODs I’ve ever done. And I was on my honeymoon.
Watch out for the lactate build up in your shoulders
4. Grace
30 Clean & Jerks For Time
60/40kg (135/90lbs)
I watched World’s Strongest Man Eddie Hall attempt the world record of this at The European Championships. He did GTOH (ground to overhead) as this loaded barbell was akin to a matchstick for him, so technically he did ‘Isabel’. But was sub 1 minute for him.
Elites are not far over 1 minute, and a number of the guys in my affiliates are sub 2 mins. It is quick, gassy and thoroughly unpleasant. The only good thing about it is that it’s out the way sharpish.
WOD Hack: 3 sets of 10 is a good strategy if you can. Or 4 7’s and a 2. If you’re breaking it down into less than 5, the desired stimulus is not being achieved, so scale. Or if you’re a hairy beast, 20/10, 15/15 or 15/10/5 rep schemes are good.

5. Nancy
5 Rounds
400m Run
15 Overhead Squats 42.5 / 30kg (155/95lbs)
I love this workout.
Although longer than the other 4 workouts above, it’s designed to be unbroken on the OHS and fast.
My best time is 11:43, so this equates to 2.34-minute rounds.
WOD Hack: If you can OHS with a narrow grip, it will help with the 15 unbroken, lessening fatigue in the wrists and shoulders.
So that’s the anaerobic top 5. What about the longer anaerobic enduro monsters?
Aerobic CrossFit WODs
Everyone into CrossFit has heard of the infamous Murph, or had the pleasure of meeting it themselves. Named after the fallen soldier. Many boxes do it in on the same weekend in the summer.
1. Murph
1-mile run
100 Pull Ups
200 Press Ups
300 Squats
1-mile run
RX Weighted Vest 9 / 6kg / 20/14lbs
This is anything from 32min to 1 hour. If you’re at the 1-hour end, you need to scale it back.
A version is available whereby you can do 5, 10 15 of each exercise for 20 rounds. However, I feel this is a copout – a completely different workout really – and it should be done in straight sets, especially if you’re RX’ing the movement.
Beginner: Break it down into those subsets if you’re less experienced.
Intermediate: Go for it if you’re intermediate; just don’t use the vest and scale the Pull-Ups.
Advanced: Don’t bother splitting sets. Put that vesty-west on
WOD Hack: Embrace the suck. It’s a good test of your endurance.

2. The Seven
- 7 Rounds For Time
- 7 Handstand Push-Ups
- 7 Thrusters 60/40kg (135/95 lb)
- 7 Knees-to-Elbows
- 7 Deadlifts 100/75kg (245/165 lb)
- 7 Burpees
- 7 Kettlebell Swings (32/24kg)
- 7 Pull-Ups
This is another favourite long one of mine.
7 reps is a very digestible amount if you can hold on. The thrusters are quite heavy, so RX is not for the faint of heart. Times are anything between 30mins and 50min+.
WOD Hack: Aim to do every set of movements unbroken, at whatever scaling you decide. It will stop you from slowing down, as 7-reps is a palatable amount to maul through. You need to pace yourself, however. It’s not a gung-ho approach.
3. Double DT (normal DT is 5 Rounds)
10 Rounds For Time
12 Deadlifts 70/50kg (155/105 lb)
9 Hang Power Cleans 70/50kg (155/105 lb)
6 Push Jerks 70/50kg (155/105 lb)
Long, heavy, hard. This will really test your muscular and respiratory endurance in how efficient is in delivering oxygen and energy to those depleted muscles, particularly in rounds 6 and onwards.
WOD Hack: Aim to do 11 Deads, followed by 1; into 8 Hang Cleans, followed by 1 then 6 Push Jerks. This strategy helps the physiological barrier of putting it down too much, and it tees you up nicely for the next round of movement.
4. Bert

- For Time
- 50 Burpees
- 400 meter Run
- 100 Push-Ups
- 400 meter Run
- 150 Walking Lunges
- 400 meter Run
- 200 Air Squats
- 400 meter Run
- 150 Walking Lunges
- 400 meter Run
- 100 Push-Ups
- 400 meter Run
- 50 Burpees
This is more bodyweight in nature, but it’s a long grind. Those with heavier frames will likely fatigue quicker than those more on the lean side. It goes to show, that you do not need a load of kit and a load of weights to get an excellent anaerobic workout in the bag.
WOD Hack: treat the run as recovery. The gains are made in big sets on the bodyweight movements. Remember to save some in the tank for the last round of 50 burpees.
5. Atlanta For Time
1-mile Run
100 Handstand Push-Ups
200 Alternating Pistols
300 Pull-Ups
1-mile Run
Wear a Weighted Vest (20/14 lb)
OK, I’ve not done this….yet.
The CrossFit Games athletes did this in 2020 as WOD 12. It looked hideously fun. By far the most fatiguing part would be the 300 Pull-Ups at the end.
Your mental and physiological resilience is truly tested here, and it’s a true test of fitness.
Can you even get through it, mentally, as well as physically?
WOD Hack: If I were to strategise this, my view (if you are RX’ing) would be 10’s on the HSPU. 20 sets of 10 Pistols. Then the Pull-Ups I would probably suggest 7’s, just as 5’s would create too many gaps, and 10 would smoke the forearms too quickly. Both runs are slow minute miles. The WOD is all about those Pull-Ups.
So this BestGymHacks.com 10 CrossFit roundup of cardio WODs, the 2 main categories they fall into, and one’s you may recognise.
When your coach is throwing in intervals, Tabata, EMOMs and other ancillary stuff, just remember, it’s all good prep for the huge variety of work you’ll be doing in your upcoming classes.