Skip to content

Build Aerobic Endurance and Capacity

Ever wondered how to build your engine? How to increase your aerobic capacity so you can last longer in WOD’s? Coach Kyle imparts some of his wisdom and learnings on just how to get that gas tank fuller!

In November of 2017 coach Bruce and I were lucky enough to attend a CrossFit speciality course, down in Durban, run by Chris Hinshaw.
We stumbled upon Chris Hinshaw through a Barbell Shrugged episode on YouTube. Safe to say, both our minds were blown by the episode which resulted in our attendance at the course.

Before we get into the nitty-gritty of what we learnt and trust me we learnt volumes, Chris Hinshaw needs a bit of an introduction.
Hinshaw, in his younger days, was a successful triathlete. He completed 10 Ironmans and his best result was second in the Hawaiian Iron Man. To put this into perspective, this is a 3.8km swim, 180km bike ride and a 42km run in the heat of Hawaii.

Due to all his volume from training for Triathlons, it ended up leaving Hinshaw feeling brittle in his forties. He came across an OG CrossFitter named Annie Sakamoto who suggested that he try CrossFit as he had been training the same muscles for years and she felt that training the other muscles would restore his functionality. Hinshaw attended one on one training sessions for 3 years, which restored his functionality and he openly and freely attributes the restoration of his functionality to CrossFit. In his own words “CrossFit saved my life and restored my health”

Hinshaw’s first athlete that he worked with was Jason Khalipa. Khalipa is an OG CrossFit athlete who was always considered a beast who dominated heavy and short WOD’s. As a result of always doing terribly in endurance WOD’s (Khalipa almost came last in a 7km trail run), he approached Hinshaw in January 2013 in order to improve his endurance, in other words, his engine.

Initially, Hinshaw was hesitant about slowing down a powerful and explosive athlete, but after working with Hinshaw, Khalipa won the Row Half Marathon and placed in the top 3 for a number of other endurance WOD’s at the 2013 CrossFit games. Clearly, Hinshaw’s work with Khalipa had made a massive improvement. After this, Hinshaw started working with Froning and Fraser. Again, Hinshaw was hesitant  but within the first six months of working with Hinshaw, all of Froning’s and Fraser’s lifts increased. The training with Hinshaw had in fact made them stronger.

This is a significant result, as these athletes are so well rounded and train so much, that PB’s seldom occur. Hinshaw now works with a myriad of Games Athletes. In order to understand why this happened and Aerobic Capacity, in general, we need to have a crash course in energy systems and the different types of muscle in the body.

In short, the human body has three different types of energy systems. The first system is the Phosphagen system. This energy system provides energy for exercise from zero to ten seconds. It is a highly explosive energy system. Think 1 rep max lifts.

The next energy system is the Glycolytic energy system. This system comes into play in anaerobic WOD’s and peaks at approximately 60 seconds. Think 400m max effort sprints.

The third energy system is the oxidative (Aerobic) energy system. This system peaks at around 90 to 120 seconds and sustains this peak thereafter. Think 1600 metre max effort runs.

With this in mind, we need to break down the different types of muscle fibres in the body.

The body is made up, in general, of two types of muscle fibres, namely slow-twitch muscle fibres and fast-twitch muscle fibres. Fast-twitch muscle fibres generally rely on the phosphagen and glycolytic energy systems to power them. Slow-twitch muscle fibres rely on the oxidative system.

With the sciency stuff out the way, we can explain why Hinshaw’s programming with Khalipa, Froning and Fraser was so successful.

CrossFitters generally approach WOD’s with the plan of going as hard and as fast as possible for as long as possible and then relying on hope to bring the WOD home, essentially relying on their phosphagenic and glycolytic energy systems (and in consequence their fast-twitch muscle fibres) to get the WOD done, with no real emphasis on their oxidative system. This means that most CrossFitters use only 50% of the muscle fibres available them.

Hinshaw programmed running WOD’s to be done twice a week with these athletes which developed their aerobic systems and in consequence developed their slow-twitch muscle fibres. This meant that the Games athletes were now developing their fast-twitch muscle fibres in their normal CrossFit programming and their slow-twitch muscle fibres with Hinshaw, which explains why all of their lifts improved as they were now using 100% of the muscles available.

The best example of this is a day of training Hinshaw experienced with Froning and Fraser where both athletes completed a running WOD of intervals totalling 5 400 metres and 1 hour afterwards, both Froning and Fraser achieved personal bests in their clean and jerk.

In order to determine whether an athlete needs to develop their slow-twitch or fast-twitch muscle fibres, Hinshaw uses the ratio between their 400-meter max effort run time and their 1 600 metre max effort run time. The ratio between these two times determines whether slow-twitch or fast-twitch muscle fibres need developing.

Hinshaw uses running as his most effective means of improving aerobic capacity, as running gives you the highest value for the time spent, however, aerobic capacity WODs can be done on a rower or on the assault bike.

With running, you are supporting your own body weight which can help you feel the different intensities of a workout. You can imitate a Fran type WOD (short and fast) or Kalsu type WOD (long and slow) with effective running intervals, which will teach you how each WOD feels. This in turn will teach you how to pace WODs in different time domains. Pacing is another theme which requires its own article altogether.

Essentially, aerobic capacity requires you to spend time on the road, on the bike or on the rower, moving at different speeds. This may seem boring, but with good programming, a running WOD can be engaging and stimulating. Each WOD will teach you something about how to pace a WOD. It is not about merely plodding through a 5km run or row. It is about having something you can measure and achieve on every WOD.

The only way to develop your aerobic capacity is to spend time going slower. So get those running shoes on, jump on that rower or bike and spend some time developing your aerobic system. If the games athletes do it, so should you. The benefits you will see will be enormous.


Coach Bruce and I are doing Chris Hinshaw’s running WODs twice a week. If you have any questions or want to join us, come chat to us.

Back To Top