In the fitness world, cardio tends to be a highly debated topic. Some people claim you should never do cardio, especially if you’re trying to build muscle. Others say you should do lots of cardio, no matter what your goals are. Other debates argue the merits of high-intensity interval training (HIIT) vs. low-intensity [long-duration] steady state training (LISS); frequency of cardio workouts; timing of cardio (before resistance training or after resistance training or on a separate day); and so forth.

People perform cardio workouts for many reasons, but most athletes do it to improve their body composition or lose body fat. In this regard, many people view cardio as a necessary evil. Spending endless hours slaving away on the treadmill or elliptical machine is seen as a rite of passage. It’s what you have to do to get that ripped look.

Different Types of Cardio

Traditional cardio workouts can be rather boring and monotonous—and generally, they suck. This is the kind of workout most people think of when they hear the word cardio: low-intensity, long-duration activity such as walking fast or slowly on an incline. But although this type of cardio does suck, it has almost zero impact on muscle loss, so it is typically what heavyweight bodybuilders do. On the flip side, it burns very few calories and takes forever, generally 45-60 minutes, 6-12 times per week.

Fortunately, other cardio options are available.

First, there is medium- to high-intensity, steady state cardio. This is more effective at burning calories than low-intensity, steady state cardio, and it is far more time-efficient. It has been used for years by thousands of people as a tool to improve body composition. The downside is that although it takes less time than low-intensity, long-duration cardio, it still requires a significant time investment because it does not increase the body’s metabolism post-workout. To make matters worse, this style of workout can also increase cortisol levels, which can result in decreased muscle mass and increased storage of body fat.

RELATED: STUDY: Will Cardio Ruin Your Strength Workouts?

The second, and arguably the best, style of cardio is high-intensity interval training—short bursts of max effort followed by brief periods of active rest, repeated several times. Typical interval recommendations are 30 to 60 seconds of all-out high-intensity bursts followed by 60- to 120-second active rest periods, repeated for a total of 15 to 30 minutes. In a recent review of the scientific literature involving cardio workouts, Dr. Jacob Wilson of the University of Tampa found that short-duration, high-intensity cardio workouts were better for strength and hypertrophy gains and better for fat loss than traditional forms of cardio. Although HIIT doesn’t burn a lot of fat during the workout itself, it does have profound effects post-workout, including increased EPOC (excess post-exercise oxygen consumption) and fat oxidation, enhanced mitochondrial density and muscular hypertrophy, and improved muscle glucose disposal.

Note: This style of cardio workout is not for the faint of heart or the guy who thinks 30 minutes on the elliptical while browsing Instagram on his phone is “butt-kicking cardio.”

RELATED: I Do Cardio Workouts But I’m Still Fat. What’s Wrong?

Sample Cardio Workouts

Sprints

Sprints are probably the easiest way to get in a quick and effective cardio session. Not only are they extremely effective for helping carve out those striations, they can also help you build a decent pair of legs. With sprints, you want to work your way up, starting off small and slowly increasing difficulty over time, either by running longer distances or reducing rest time between sprints. Below is a sample progression of sprints, starting with 10 40-yard sprints with 90 seconds of rest and building from there.

• Week 1 – 40 yards x 10 (90 seconds rest)
• Week 2 – 40 yards x 12 (90 seconds rest)
• Week 3 – 40 yards x 15 (90 seconds rest)
• Week 4 – 40 yards x 20 (90 seconds rest)
• Week 5 – 40 yards x 20 (90 seconds rest)
• Week 6 – 40 yards x 20 (75 seconds rest)
• Week 7 – 50 yards x 16 (75 seconds rest)
• Week 8 – 50 yards x 20 (75 seconds rest)
• Week 9 – 50 yards x 20 (60 seconds rest)
• Week 10 – 60 yards x 15 (60 seconds rest)

Complexes

Originally created by Istvan Javorek, complexes have recently been made popular thanks to CrossFit. To perform them, pick two or more exercises that use the same piece of equipment (e.g., barbell, kettlebell or dumbbell), choose your number of sets and reps and your load, and perform the exercises back-to-back-to back. Below are some sample complexes with rest and progressions.

• Beginner Complex (with a kettlebell): Two-handed KB Swing, Goblet Squat, Push Press
• Intermediate Complex (with a kettlebell): Alternating KB swing, Clean and Press (each arm), Windmill (each arm), Overhead Squat (each arm).
• Advanced Complex (with a barbell): Jump Shrug, Front Squat, Push Press, Hang Snatch, Overhead Squat, Stiff-Legged Deadlift, Plyometric Pushups

Note: Do not start too heavy. Trust me, even with a relatively light load, these will push you to the limit. Don’t put down the equipment between movements. A set is not completed until all the repetitions of each exercise are done. Pace yourself! You want to push yourself, but be mindful of the amount of volume you will be doing.

Volume/Rest Progression

Weeks	Sets x Reps	Rest
1-2	3×6	2 minutes
3-4	3×7	2 minutes
5-6	3×8	90 seconds
7-8	3×9	90 seconds
9-10	3×10	75 seconds

Timed Sets

This style of cardio workout from Alwyn Cosgrove is a hybrid between metabolic training and strength training. Timed sets are similar to complexes except you race against the clock. The goal is to move through the workout as quickly as possible (which  CrossFit has brought back into the spotlight). Select five exercises and pick a weight you can lift comfortably for 10-12 repetitions. Set the clock for 10, 15 or 20 minutes and proceed through the exercises as fast as you can. See how many sets you can complete in the selected time period.

Sample Timed Set: Hang Clean, Front Squats, Dips, Pull-Ups, Spiderman Push-Ups.

To make it more challenging, manipulate the workout variables. For example, do the following exercises, but perform 20 repetitions of the lower-body ones and 10 repetitions for the upper-body ones, switching back and forth on each set, and perform a total of five sets.

20 Burpees. 10 Push-Ups,  20 Squat Jumps, 10 Inverted Rows

That’s it. Simple and effective!

The World-Famous Tabata Protocol

These are timed intervals. The biggest difference from HIIT workouts is that Tabata involves negative rest intervals—i.e., rest periods are shorter than the work periods. This is my personal favorite. Below is a sample routine done on an AirDyne bike

AirDyne Tabata
Six rounds using a 20/10 (work/rest) ratio for a total of 2:50.
Rest for 3 minutes.
Repeat with another six rounds using the same 20/10 ratio

This can be done in a variety of ways, including Jumping Rope, Burpees, Kettlebell Swings, and so forth.

Last but not least, I want to share Dr. Layne Nortons’s 15-minute cardio routine. This one is done on a stationary bike as follows:

• Perform a 5-minute warm-up using half of the bike’s max resistance.
• Pedal as fast as you can for 10 seconds.
• Increase the resistance to the maximum setting and maintain your pedaling speed. Do this for 20 seconds.
• Go back to an easy pace and lower resistance for 90 seconds.
• Repeat the above (minus the warm-up) until you hit 15 minutes.

That’s it! A few cardio workout options instead of slaving away on the treadmill for countless hours in the gym.

RELATED: Try This Bodyweight Cardio Workout

[cf]skyword_tracking_tag[/cf]