How You Can Build Muscle With Cardio Workouts

Be bigger, stronger, faster—the universal desire of athletes. To achieve these goals, a training program moves through muscle gain, strength and power phases.

However, I always ran into a problem. During the initial hypertrophy (muscle gain) phase, athletes would often be too gassed to complete their workouts. We had to reduce the load just so they could get all their work in.

Over time, I found the solution: Perform  approximately 2 weeks of aerobic base building before starting a hypertrophy phase. Essentially, do cardio for muscle gain.

Much of the research on muscle gain shares one commonality: You need to train with a high volume to maximize gains in size. This means training with a lot of sets, reps and a decently heavy load.

To achieve this high volume of training, you need two things—fast short-term recovery (within a workout) and fast long-term recovery (between workouts).

Developing the aerobic system works on both.

Aerobic System and Short-Term Recovery

Say, for example, you perform a heavy set of 5 Back Squats. Your body mainly uses its anaerobic energy system—using up ATP/PCr and glucose to crank out reps. However, once the set is completed, you rely on your aerobic system to restore these fuel sources and prepare your body for another set.

A better aerobic system leads to faster recovery between sets. Instead of resting 3 minutes, you may only need to rest 1 minute.

This means you can accumulate more volume because less time is spent resting and more time is spent lifting.

Aerobic System and Long-Term Recovery

Your body's autonomic nervous system has two sides: parasympathetic (rest and digest) and sympathetic (fight or flight).

Aerobic training provides an adaptation to increase parasympathetic activity and decrease sympathetic activity. This leads to accelerated recovery between workouts as the body is in a deeper recovery state.

As recovery is enhanced between workouts, you can enter every session fresher and more ready to perform. This leads to increased volume over the course of weeks and months.

Other Benefits of Aerobic Training


Increased capillarization (i.e., delivery of growth factors and nutrients to muscle tissue). In a study on healthy older men, those with low capillarization saw no muscle gain from 24 weeks of resistance training, whereas those with high capillarization saw significant muscle gain from the same training. Aerobic training increases capillarization.

Better performance during longer efforts. During 80% 1RM reps-to-failure, the aerobic system contributed approximately ¼ to the performance of the Bench Press, Tricep Extension and Lat Pulldown. In the 200-, 400-, 800-, and 1500-meter events, the aerobic system contributed 29, 43, 66, and 84% to performance. Developing the aerobic system could provide increased performance during longer duration bouts.

How to Develop Your Aerobic System

After the competitive season, train aerobically with your heart rate in the 135-155 bpm range. This can be done with light circuits (basic pushing, pulling, squatting, and hinging exercises), biking, jogging, the contralateral aerobic circuit (created by Cal Dietz), or really anything where your heart rate is elevated to zone 2 for ~1 hour. Train about 4 days per week in this fashion. Once you've completed a couple weeks of this training, start your hypertrophy phase. Your ability to manage high volume training will be significantly improved.

Next time you're wondering why you can't train with enough volume to gain muscle, take a step back and work on your aerobic system. It could be what's limiting you from making the gains in muscle you want.



Snijders, T., Nederveen, J. P., Joanisse, S., Leenders, M., Verdijk, L. B., van Loon, L. J., & Parise, G (2016). "Muscle fibre capillarization is a critical factor in muscle fibre hypertrophy during resistance exercise training in older men." Journal of Cachexia, Sarcopenia and Muscle, 8(2), doi: 10.1002/jcsm.12137.

Vianna, J. M., Lima, J. P., Saavedra, F. J., & Reis, V. M. "Aerobic and anaerobic energy during resistance exercise at 80% 1RM." (2011). Journal of Human Kinetics, 29A. 69-74.

Spencer, M. R. & Gastin, P. B. (2001). "Energy system contribution during 200- to 1500-m running in highly trained athletes." (2001). Medicine and Science in Sports and Exercise, 33(1), 157-62.

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