Increase Your Aerobic Capacity

Increase your Aerobic Capacity

Lets fine start by defining what “aerobic” means. It is NOT Jane Fonda doing some random kicks and rolls on the floor (I think thats what she did, I don’t really know…). Aerobic exercise is exercise that is sustainable, repeatable and has the intent of improving your body’s capacity of absorbing and transporting oxygen to your muscles. Often, aerobic exercise is thought of as primarily movements we might consider “cardio” – Running, biking, swimming, jumping rope, etc. However, You can make any exercise “aerobic” as long as it is sustainable, and repeatable. On the flip side, you can make any exercise “anaerobic” by doing it at high intensity.

Anaerobic exercise is NOT sustainable. The biggest mistake in aiming to improve your aerobic capacity is doing work that you think is aerobic, but is actually anaerobic. For example, if you want to improve your 5k run time, and you go out and run a 5k a bunch of times as hard as possible, you’re never actually training your aerobic system. Instead, you maybe want to run 1k at your goal 5k pace, rest 4:00 and repeat 6-7 times. The idea is to work at a pace you can that is challenging, but you can sustain. Then recover fully & repeat. The reason being that to improve your 5k time, you want to increase your capacity to stay aerobic for longer. For example, during your 5k time trial, maybe you go from feeling good and sustainable (aerobic system), to simply surviving (anaerobic system) around the 12:00 mark. If we can train you to make the sustainable portion of your run last to 15 or 18 minutes, your time on the 5k time will be much and you will feel less awful at the end!

Below is an example of what pacing an aerobic workout might look like for improving your 5k time, vs what happens when most people try to run intervals.


In green, the athlete ran at a sustainable pace, rested, then hit that sustainable pace each interval. Notice, the athlete also stayed under his/her threshold. The idea over time is to raise that threshold and we do that by getting very close to it, but not exceeding it. As you can see, the athlete in orange went out way to fast, exceeded his threshold, didn’t rest long enough, and repeated. The problem here is that he/she did not spend enough time close to the threshold to move it upward and improve capacity. Instead he/she simply redlined a bunch of times.

For many of us, the hardest part of aerobic training is patience & discipline. You have to do a lot of boring work : rest intervals and stop yourself from the urges of going to fast. Often, athletes get too caught up in getting a “good workout” and forget the intent of the workout in the first place!

Anaerobic and aerobic exercise both have their place in training. The most important thing is to know which you are trying to train, and pacing the workout accordingly!

If you want help improving your aerobic capacity, reach out to a coach to talk about what a training plan for you might look like!


Coach Andrew