How to Do Cardio When You're Building Muscle Mass (and Why)

Want to build muscle mass, but not sure about cardio? You’ve come to the right place.

First, the basics:

But you may still want to do cardio. Why?

  • There is evidence it prevents 26 diseases
  • It improves your cardiovascular fitness and speeds up your overall recovery
  • High-intensity interval training (HIIT) is the most efficient cardio for fat loss (Boutcher, 2001)

So, I usually recommend it twice a week to clients who want to do cardio.

Guidelines for cardio when building muscle mass

  • Twice a week
  • 20 minutes per session
  • Alternate slow and fast intervals
  • Stationary bike is safest
  • Same day you train legs, at the end of your workout

No equipment? Jogging and running can work. Just make sure you don’t exhaust yourself to the point where your running technique goes bad and you turn an ankle.

These are basic guidelines. You may want to adapt them to your situation and progress over time (Dr. Muscle will help you with that part).

New to interval training?

If you’re completely new to interval training, check out this tutorial:

How to add cardio to your program in Dr. Muscle

Option 1 (easiest): Toggle on Cardio under Settings

By default, Dr. Muscle does not include cardio in your program. But you can add it easily. This options adds a cardio exercise (HIIT Cardio) at the end of all your workouts. Here’s how:

  1. Tap More (bottom bar)
  2. Tap Settings
  3. Scroll down to and toggle on Cardio

Option 2 (most flexible): Add custom cardio exercises to your program

Here’s how you would go about adding custom cardio exercises to your program:

  1. Create a custom exercise (e.g. “HIIT Bike”)
  2. Answer “Yes” to “Is this a bodyweight exercise?”
  3. Answer “Seconds” to “Should this exercise progress in reps or seconds?”
  4. Answer how long you want your work intervals to be (e.g. 30 seconds)
  5. Finish setting up the exercise, add it to your workout, and edit its options
  6. Toggle on “Use custom set style” and “Normal sets”
  7. Toggle on “Use custom warm-ups” and set it to zero
  8. When you get to that exercise in your workout, set the timer to however long you want to rest between intervals (e.g. 120 seconds) and toggle off “Automatch reps”

And you’re good to go! Now, when you start biking, you’ll do “sets” (intervals) of 30 seconds with 120 seconds of rest in between. By default, the app will recommend 2-5 intervals based on your progression. You can add or remove sets on the fly; the app will remember your changes and adjust in one workout.