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. Here’s how:

  1. Tap Settings (bottom bar)
  2. Look for Cardio
  3. Toggle on

This options adds 10-20 min of cardio exercise (HIIT style) at the end of all your workouts.

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. Tap Exercise (bottom navigation)
2. Tap Exercises
3. Tap the big plus button at the bottom right corner
4. Enter the name of your new exercise
5. Tap cardio on exercise type
6. Choose Both sides together
7. Enter how many seconds you can do easily
8. Tap continue to finish setting up the exercise.

To adjust the exercise settings, do this:

1. Tap More next to the exercise
2. Tap Exercise settings
3. Toggle on "Use custom set style" and select "Normal sets" from the dropdown
4. Toggle on "Use custom warm-ups" and set it to zero
5. Tap Save warm-up sets
6. Enter the number of your custom work sets under "Work sets"
7. Tap Save work sets

To add the exercise into your workout, do this:

1. Tap Home (bottom navigation)
2. Open your workout
3. Tap Edit workout on the top left
4. Toggle on the exercise from My exercises section
5. Tap next
6. [Optional] choose to reorder your exercises
7. Tap save workout

If you want to set up a custom rest interval, do this:

  1. Tap the timer icon in the top right
  2. Enter your your time using -/+
  3. 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.